JP2005071798A - Lighting system, electro-optical device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system capable of improving the uniformity of a luminance distribution by changing a luminous energy distribution of inside propagation light in a light guide member by deflecting light emitted from a light source. <P>SOLUTION: This lighting system 100 has: the light sources 111 and 112; and the light guide member 120 for introducing light emitted from the light sources 111 and 112 from an end face 121 to emit it from a front surface 122; and is formed, inside the end face 121 of the guide member 120 and in a front area in the optical axis direction of the light sources 111 and 112, with reflecting surfaces 124a and 125a capable or reflecting at least a part of the inside propagation light of the guide member 120 in the sideward direction with respect to its incident direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an illuminating device, an electro-optical device, and an electronic apparatus, and in particular, an optical configuration of an illuminating device including a light source and a light guide member that introduces light emitted from the light source at an end surface and emits the light from the surface. About.

  Conventionally, a plurality of light emitting diodes (hereinafter simply referred to as “LEDs”) are arranged along the end face of the light guide plate, and light emitted from these LEDs is incident on the light guide plate, and from the surface of the light guide plate. Sidelight type illumination devices configured to emit light have been devised (see, for example, Patent Document 1 and Patent Document 2). Such an illuminating device is used as a backlight of a liquid crystal display device.

  In FIG. 13, the schematic plan view of the illuminating device 400 which has said structure is shown. The illuminating device 400 generally includes a light source unit 410 including a plurality of chip-like LEDs 411, 412, 413, and 414, and a light guide plate 420 having a light-transmitting rectangular shape in plan view. In the light source unit 410, a plurality of LEDs 411 to 414 are mounted on the circuit board 415. These LEDs 411 to 414 are distributed almost uniformly along one end surface 421 of the light guide plate 420, and the optical axes 411a to 414a of the respective LEDs 411 to 414 are all set to face in a direction substantially orthogonal to the end surface 421. Is done.

The LEDs 411 to 414 each have a fan-shaped light emission range centering on the optical axes 411a to 414a, and these light emission ranges usually have an extent of about 100 to 120 degrees. Light emitted from the plurality of LEDs 411 to 414 is introduced into the inside of the light guide plate 420 from the end surface 421 and propagates through the inside of the light guide plate 420 while being formed on an uneven surface (not shown) formed on the bottom surface of the light guide plate 420, The light is diffused gradually in a direction perpendicular to the surface 422 by a light diffusing means composed of a print layer, a reflective layer, etc., and emitted from the surface 422. The light diffusing means basically emits the light emitted from the LEDs 411 to 414 uniformly over almost the entire surface 422, that is, the in-plane uniformity of the amount of light emitted from the surface 422 is obtained. ˜414 to a distribution density corresponding to the distribution of light introduced into the light guide plate 420.
JP 2003-66418 A (FIG. 4) Japanese Patent Laid-Open No. 10-260404 (FIGS. 1, 3, 6, and 7)

  However, in the illumination device 400 described above, the light emission ranges of the LEDs 411 to 414 are limited, and the LEDs 411 to 414 are distributed along the end surface 421 of the light guide plate 420. There is a problem in that the bright portion L and the dark portion D are alternately generated in the surface portion near the end surface 421 of the optical plate 420 in the same manner as the arrangement of the LEDs 411 to 414. For this reason, for example, when illuminating a liquid crystal display device (not shown) using the illumination device 400, it is necessary to avoid the vicinity of the end surface 421 having a large luminance unevenness, so that the effective illumination region A corresponding to the effective display region of the liquid crystal display device It was necessary to set the distance G away from 421. This distance G is set so that the luminance unevenness in the region on the end surface 421 side of the effective illumination region A of the liquid crystal display device is lower than the allowable value. However, it is difficult to completely eliminate the luminance unevenness in the width direction of the end surface 421, and it is necessary to set the distance G large when trying to reduce the luminance unevenness. It is an obstacle to miniaturization. In particular, in recent years, luminance unevenness has become more conspicuous due to colorization and higher definition of display devices such as liquid crystal display bodies, and the allowable level of luminance unevenness in lighting devices is also decreasing. Maintenance is becoming difficult.

  In this case, as described in Patent Document 2 described above, by providing a lens composed of a concave curved surface at a portion of the end surface 421 that is a light incident surface of the light guide plate 420 that faces each LED, The spread of the luminous flux emitted from the LED can be adjusted by the refraction effect, and the distribution of the light propagating in the light guide plate 420 can be optimized. However, in this method, the degree of the photorefractive effect of the lens can only be adjusted by the curvature of the concave curved surface. Therefore, when the radius of curvature is reduced and the luminous flux is widened, luminance unevenness is reduced in the vicinity of the end surface 421 of the light guide plate 420. However, since the luminance decreases far away from the end surface 421, it is difficult to ensure the uniformity of the luminance in the propagation direction of the internal propagation light, and conversely, the curvature radius of the concave curved surface is increased to increase the curvature radius. When the spread of the light beam is reduced, a decrease in luminance at a distance is suppressed, but there is a dilemma that luminance unevenness increases in the vicinity of the end face 421.

  Here, it is conceivable to reduce the distance G by narrowing the distance between the LEDs 411 to 414. In this case, however, it is necessary to increase the number of LEDs in order to introduce light into the entire light guide plate without any problem. Thus, there may be a problem that the manufacturing cost increases due to an increase in parts cost and assembly cost.

  Therefore, the present invention solves the above-described problems, and the problem is that the light quantity distribution of the internally propagated light in the light guide member is changed by deflecting the light emitted from the light source, thereby making the luminance distribution uniform. It is an object of the present invention to provide a new configuration of a lighting device capable of improving the performance.

  In order to solve the above problems, an illumination device according to the present invention includes a light source and a light guide member that introduces light emitted from the light source at an end surface and emits the light from the surface. A reflection surface capable of reflecting at least a part of the internally propagated light of the light guide member laterally with respect to the propagation direction is provided in a front region in the optical axis direction of the light source. And

  According to the present invention, the light emitted from the light source is incident on the inside of the light guide member from the end face and propagates as internally propagated light. Of this internally propagated light, the light traveling toward the front in the optical axis direction of the light source. At least a part of is reflected to the side with respect to the propagation direction by the reflecting surface. As described above, the amount of the internally propagated light in the optical axis direction of the light source can be reduced by being reflected laterally by the reflection surface with respect to the propagation direction, and the width direction of the light guide member (on the optical axis of the light source). Since the light quantity distribution can be relaxed in a direction orthogonal to the direction parallel to the surface of the light guide member, the shape of the light emitting part of the light source and the light source can be adjusted by appropriately adjusting the position of the reflecting surface and the reflection angle. It is possible to make the light quantity distribution of the internally propagating light, which has been restricted by the arrangement of the light source, uniform, and improve the uniformity of the luminance of the illumination light emitted from the light guide member.

  In particular, the conventional method using the photorefractive effect of the lens cannot take a large deflection angle of light and only has a deflection action when light enters the light guide plate. It is difficult to essentially eliminate the situation where the light intensity of the internally propagated light is excessive in the region and the light intensity is insufficient in the region deviated from the front to the side. It is impossible to change the light quantity distribution significantly. On the other hand, according to the present invention, by providing a reflective surface in the front area in the optical axis direction of the light source, it is possible to largely deflect the internally propagated light propagating through the front area to a side at a large angle. For this reason, the light amount distribution in the width direction of the light guide member can be significantly changed.

  Here, the side refers to either the left or right direction on the plane parallel to the surface that is the light exit surface with respect to the incident direction of light, and is reflected laterally with respect to the propagation direction. Including the case of reflecting in a direction parallel to the surface that is the light exit surface and the case of reflecting in a direction inclined with respect to the surface, the case of reflecting in a direction orthogonal to the surface is not included. In addition, the reflecting surface may be formed of a surface of a light reflecting material such as metal, or, as described below, the light guide member configured to be capable of totally reflecting internal propagation light. It may be the surface.

  In the present invention, it is preferable that the reflecting surface is an inner surface configured to be able to totally reflect a part of the internal propagation light in the light guide member. According to this, if the light guide member is made of a material having a higher refractive index than that of the surrounding medium (for example, air), the light guide member has a surface orientation that allows total reflection with respect to the internal propagation light. Since it is only necessary to form the inner surface, it is not necessary to use a light reflective material, and it can be easily formed. This inner surface can be constituted by, for example, a flat surface inclined laterally with respect to the optical axis direction of the light source, or a curved surface having a portion inclined laterally with respect to the optical axis direction. Here, in addition to forming holes and recesses to be described later, the inner surface is provided with a closed space (cavity) inside the light guide member, or another material having a light refractive index smaller than that of the light guide member. It can also be configured by arranging an embedded object composed of

  In this invention, it is preferable that the said reflective surface is comprised by the inner surface of the hole formed in the said light guide member. When the reflective surface is formed on at least a part of the inner surface of the hole provided in the light guide member, it can be provided relatively easily by molding or cutting. Here, the hole is preferably a through-hole penetrating from the front surface to the back surface of the light guide member. In this case, when the light guide member is a plate-like body, the depth of the hole may be small, so that it can be formed more easily, and the plane orientation of the reflecting surface can be easily set by the sectional shape of the hole. Here, the reflective surface can be configured by arranging a light reflective material on the inner surface of the hole (for example, filling the hole with the light reflective material), or at least a part of the inner surface of the hole may be formed as described above. It is also possible to make the inner surface itself capable of total reflection.

  In this invention, it is preferable that the said reflective surface is comprised by the inner surface of the recessed part formed in the said light guide member. When the reflective surface is configured on at least a part of the inner surface of the recess formed in the light guide member, the area of the reflective surface can be adjusted by the depth of the recess, and the region where the recess has not reached Can be configured so as not to cause the action of the reflecting surface. Therefore, it becomes possible to adjust the light quantity of the internally propagated light due to the reflection of the reflecting surface by changing the depth of the recess. Here, the reflective surface can also be configured by disposing a light reflective material on the inner surface of the concave portion (for example, filling the hole with the light reflective material), or at least a part of the inner surface of the concave portion is formed as described above. It is also possible to make the inner surface itself capable of total reflection.

  In this invention, it is preferable to have the opposing reflective surface which is arrange | positioned in the position which left | separated from the front area | region of the optical axis direction of the said light source to the side. According to this, the light emitted from the light source is incident on the end face of the light guide member and becomes internally propagated light. Of this internally propagated light, the light propagating in the vicinity of the optical axis direction of the light source is the front in the optical axis direction. Is reflected to the side by the reflecting surface disposed at the side, and then reflected again by the opposing reflecting surface facing the reflecting surface, so that at the position away from the front region in the optical axis direction of the light source, The reflected light can be further propagated away from the light source. That is, a part of the internally propagating light propagating toward the front region in the optical axis direction of the light source can be moved and propagated to a position away from the front region in the optical axis direction. It is possible to alleviate the light quantity distribution of the internally propagated light that is concentrated in the front area in the direction, and it is possible to reduce the unevenness of the brightness of the light guide member as a whole. Here, the said opposing reflective surface can be comprised in the inner surface of a hole or a recessed part similarly to the said reflective surface.

  In this invention, it is preferable that the said reflective surface and the said opposing reflective surface are comprised substantially mutually parallel. Since the reflecting surface and the opposing reflecting surface are configured to be substantially parallel to each other, the internal propagation light can be moved to a position deviating from the front region without changing the propagation direction. Therefore, the internally propagated light propagating in the optical axis direction of the light source propagates almost in the optical axis direction even after moving to the side by the reflecting surface and the opposing reflecting surface. Therefore, a brighter lighting device can be provided.

  In the present invention, it is preferable that two sets of the reflecting surface and the opposing reflecting surface are provided substantially symmetrically on both sides of the optical axis. According to this, the internally propagating light propagating to the front surface in the optical axis direction of the light source is reflected to both sides by the pair of reflecting surfaces on both sides of the optical axis, and further, a pair of facing surfaces facing each other. Since it is reflected again by the opposing reflecting surface, the internally propagated light can be moved to both sides away from the front area of the light source. Therefore, the luminance distribution in the width direction of the light guide member can be made more uniform.

  In the present invention, it is preferable that the reflection surface and the counter reflection surface have a function of reducing a variation in the propagation direction by converging the propagation direction of the internal propagation light in a predetermined direction. The variation in the propagation direction of the internal propagation light is reduced by the reflection surface and the counter reflection surface, so that the light use efficiency in the light guide member (the ratio of the light component that becomes the illumination light in the internal propagation light of the light guide member) is increased. be able to. Here, the function of reducing the variation in the propagation direction of the internally propagated light is, for example, when the light source is a point light source and the propagation direction of the internally propagated light is widened even inside the light guide member, the above reflection The optical characteristics of the optical system composed of the reflective surface and the counter-reflecting surface are converted into a parallel beam by converting the optical characteristics of the optical system composed of the reflective surface and the counter-reflecting surface by a method such as making one of the surface and the counter-reflecting surface concave. It should be.

  In this invention, it is preferable that the back surface of the said light guide member is provided with the inclination optical surface which faces the said predetermined direction, and deflects the said internal propagation light to the said surface side. According to this, the internally propagating light propagating through the inside of the light guide member is deflected to the surface side by the inclined optical surface, but the inclined optical surface directly faces in a predetermined direction (that is, guides the normal line of the inclined optical surface). The projection line projected onto the surface of the member is parallel to the predetermined direction), so that the internally propagated light focused in the predetermined direction as described above is efficiently converted into effective illumination light. Can be emitted. That is, when the propagation direction of the internal propagation light and the orientation of the inclined optical surface are different from each other, the internal propagation light is deflected to the surface side of the light guide member by the inclined optical surface. , Because it is deflected obliquely in a direction having a large angle with the incident direction of the internally propagating light, the emission angle from the surface of the light guide member becomes large, and it may be difficult to obtain effective illumination light. When the inclined optical surface faces the propagation direction of the internal propagation light, the internal propagation light is close to the original direction expected by the inclination angle of the inclined optical surface, for example, the normal direction of the surface of the light guide member Since it is deflected in the direction and the emission angle becomes small, it becomes effective illumination light. Therefore, when the propagation direction of the internal propagation light is focused in a predetermined direction as described above, the internal propagation light can be efficiently emitted as illumination light.

  An electro-optical device according to the present invention includes any one of the illumination devices described above and an electro-optical panel configured to be able to display with illumination light of the illumination device. According to this, the display quality of the electro-optical panel can be improved by making the luminance distribution of the illumination device uniform. In addition, by increasing the area ratio of the region where the luminance distribution is uniform in the lighting device, it is possible to increase the area ratio between the display screen and the surrounding region (so-called frame region). It is possible to increase the size of the display screen without changing the size of the device, or to reduce the size of the device while ensuring the area of the display screen.

  An electronic apparatus according to an aspect of the invention includes the electro-optical device described above and a control unit that controls the electro-optical device. In such an electronic device, since the enlargement of the display screen in the electro-optical device and the miniaturization of the device can be compatible as described above, it is particularly suitable for a portable electronic device.

  Next, embodiments of an illumination device, an electro-optical device, and an electronic apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

[First Embodiment: Lighting Device]
First, a first embodiment of a lighting device according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a schematic cross-sectional view showing a planar shape of the illumination device of the present embodiment, and FIGS. 2A and 2B are longitudinal sectional views of the illumination device of the present embodiment.

  The illuminating device 100 includes light sources 111 and 112 configured by LEDs and the like, and a light guide member 120 having light transmittance. The light guide member 120 is configured as a plate-like body. The light guide member 120 has a substantially rectangular (square or rectangular) planar shape. The light sources 111 and 112 are basically point light sources having a light emission surface with a width that is significantly smaller than the width of the light guide member 120 (the left-right width in the drawing). The optical axes 111a and 112a of the light sources 111 and 112 are set in a direction substantially orthogonal to the longitudinal direction of the end surface 121 of the light guide member 120 (that is, the width direction of the light guide member 120). The light guide member 120 includes an end surface 121 that is a light incident surface facing the light sources 111 and 112, a surface 122 that is a light emitting surface, and a back surface 123 that is formed on the opposite side of the surface 122. The light guide member 120 can be made of a transparent member, for example, a transparent resin such as polycarbonate, acrylic (PMMA resin, etc.), cycloolefin polymer, or the like. The light emission surfaces of the light sources 111 and 112 are in contact with or opposed to the end surface 121 with a very small interval. In the present embodiment, a plurality of light sources 111 and 112 are distributed along the end surface 121 of the light guide member 120 in the width direction (the left-right direction in the drawing) of the light guide member 120. Further, a light reflecting sheet 130 is disposed on the back surface 123 of the light guide member 120 as necessary. The light reflecting sheet 130 has a mirror reflection surface or a white scattering surface.

  The light guide member 120 is formed with a hole 124 (see FIG. 2A) penetrating the front and back in the vicinity of the end surface 121 or a recess 125 (see FIG. 2B) provided on the back surface 123. The hole 124 or the recess 125 is disposed in the front area in the optical axis direction of the light sources 111 and 112. These holes 124 or recesses 125 have a substantially triangular planar shape.

  Inner surfaces 124a and 125a, which are inner surfaces of the holes 124 or the recesses 125 on the light sources 111 and 112 side, are inclined sideways (in the horizontal direction in the drawing) with respect to the optical axis direction. Further, these inner surfaces 124 a and 125 a are configured to be substantially orthogonal to the surface 122. In the hole 124 or the recess 125, a pair of left and right inner surfaces 124a and 125a are disposed substantially symmetrically with respect to the optical axes 111a and 112a in the front region in the optical axis direction of the light sources 111 and 112. The pair of inner surfaces 124 a and 125 a constitute two sides on the light source side of the triangle in the planar shape of the hole 124 or the recess 125.

  Further, on the side of the hole 124 or the recess 125 (that is, on both sides in the width direction of the light guide member 120), a hole 126 penetrating the front and back or a recess 127 provided on the back surface 123 is formed. The hole 126 or the recess 127 includes inner surfaces 126a and 127a that are inclined (or opposed) in the opposite direction to the inner surfaces 124a and 125a. More specifically, the pair of inner surfaces 126a and 127a are provided so as to be inclined in the direction opposite to the optical axis direction from the inner surfaces 124a and 125a. The inner surfaces 126a and 127a are formed so as to be substantially orthogonal to the surface 122. And the hole 126 or the recessed part 127 is provided with the substantially triangular planar shape which faced the said optical axis direction reverse direction with respect to the said hole 124 or the recessed part 127. FIG.

  In this embodiment, the light emitted from the light sources 111 and 112 is incident on the inside of the light guide member 120 from the end surface 121 and propagates in the light guide member 120 in the optical axis direction (upward direction in the drawing). Propagated light. Here, since the light sources 111 and 112 are basically point light sources, the above-mentioned internally propagated light that is the emitted light becomes a diffused light beam that spreads in a fan shape in a predetermined angle range as viewed from the light source, and the light guide member The light propagates in the interior of 120 while spreading in the width direction of the light guide member 120. A part of the light propagating toward the front region in the optical axis direction of the light sources 111 and 112 in the internal propagation light is incident on the inner surfaces 124 a and 125 a of the hole 124 or the recess 125.

  Here, the inner surfaces 124a and 125a are formed to be inclined with respect to the optical axis direction, and are configured such that at least a part of the incident light is reflected by total reflection. That is, since the light guide member 120 is made of a material having a light refractive index larger than 1, the internally propagated light undergoes total reflection when the incident angle with respect to the surface of the light guide member 120 increases to some extent. The inner surfaces 124a and 125a are configured to be able to totally reflect at least a part of the internal propagation light generated by the light emitted from the light sources 111 and 112. The refractive index of the light guide member 120 is preferably about 1.3 to 1.6. In this case, when the surrounding medium of the light guide member 120 is air, the internal propagation light of the light guide member 120 is The incident angle at which total reflection occurs when entering the surface of the light guide member, that is, the total reflection angle is about 40 to 48 degrees. However, when there is a surrounding medium whose optical refractive index is larger than that of air, the total reflection angle becomes larger than the above range. In any case, it is preferable that the inner surfaces 124a and 125a are inclined so that the normal lines of the inner surfaces 124a and 125a and the optical axes 111a and 112a of the light sources 111 and 112 have an angle greater than the total reflection angle. For example, in this embodiment, the inner surfaces 124a and 125a are inclined about 45 degrees with respect to the optical axis direction of the light sources 111 and 112, and the total reflection angle is about 42 to 43 degrees.

  In the present embodiment configured as described above, a part of the internally propagated light propagating from the light sources 111 and 112 side is lateral (in the width direction of the light guide member 120) on the inner surfaces 124a and 125a which are the reflection surfaces. ) Is reflected. And this reflected light is reflected again by the inner surfaces 126a and 127a which are the opposing reflective surfaces formed in the side. At this time, since the inner surfaces 124a and 125a and the inner surfaces 126a and 127a are formed substantially in parallel, the light reflected again by the inner surfaces 126a and 127a is not incident on the inner surfaces 124a and 125a. It travels in almost the same direction as the traveling direction of the internal propagation light. That is, the propagation direction of the internal propagation light is hardly changed by the optical system constituted by the inner surfaces 124a and 125a and the inner surfaces 126a and 127a, but the propagation position is moved in the width direction of the light guide member 120. The light beam propagates to a position off the front surface in the optical axis direction of the light source.

  Therefore, in this embodiment, the internal propagation based on the light emitted from the light sources 111 and 112 is performed by the optical system configured by the inner surfaces 124a and 125a serving as the reflecting surfaces and the inner surfaces 126a and 127a serving as the opposing reflecting surfaces. Since the light is partially shifted laterally from the front area in the optical axis direction of the light sources 111 and 112, the light intensity in the front area in the optical axis direction of the light source is reduced and deviates from the front in the optical axis direction of the light source. Since the light intensity in the region increases, the light quantity distribution of the internally propagated light in the light guide member 120 in the width direction of the light guide member 120 can be relaxed.

  In particular, in the present embodiment, the pair of inner surfaces 124a and 125a corresponding to the reflection surfaces formed in the front region in the optical axis direction of the light source are formed substantially symmetrically on both sides of the optical axis. Since the inner surfaces 126a and 127a, which are a pair of opposed reflecting surfaces, are formed almost symmetrically on both sides, the light reflected on both sides of the front region is also almost equal. The light is uniformly re-reflected and propagates through the light guide member 120 almost symmetrically. As described above, the two sets of the reflecting surface and the opposing reflecting surface are provided substantially symmetrically on both sides of the optical axis, so that the internal propagation light can be shifted and propagated substantially evenly on both sides of the optical axis. Therefore, since a uniform light amount distribution can be realized in the width direction of the end surface 121, the luminance uniformity of the surface 122 of the light guide member 120 can be further improved.

  As shown in FIG. 2A, when forming the holes 124 and 126 (126 is not shown, the same applies hereinafter), the inner surfaces 124a and 126a extend over the entire thickness direction of the light guide member 120. Of the internally propagated light based on the light emitted from the light sources 111 and 112, the light is directed toward the front area of the light source, and is incident on the inner surfaces 124a and 126a at an angle equal to or greater than the total reflection angle. All incident light with a corner is reflected to the side. In addition, light incident on the inner surfaces 124a and 126a at an incident angle smaller than the above-described total reflection angle may pass through the holes 124 and 126 and may be slightly changed in propagation direction due to refraction, but is directed almost in the same direction. Then, the light propagates through the light guide member 120.

  On the other hand, as shown in FIG. 2B, when forming the recesses 125 and 127 (127 is not shown, the same applies hereinafter), the inner surfaces 125 a and 127 a are part of the thickness of the light guide member 120. Since it is formed only in the range, that is, only in the region corresponding to the depth range of the recesses 125a and 127a, in the thickness range of the light guide member 120 where the recesses 125a and 127a do not reach, the internal propagation light remains as it is. Pass above 127 as it is. Therefore, it is possible to adjust the amount of internal propagation light reflected to the side by the depth of the recesses 125 and 127, and as a result, the light quantity distribution of the internal propagation light viewed in the width direction of the light guide member 120 is optimal. It becomes possible to become.

  In order to enhance the above effect, the optical structure having the reflective surfaces (inner surfaces 124a and 125a) and the opposing reflective surfaces (inner surfaces 126a and 127a) is preferably formed in the vicinity of the end surface 121. By forming this optical structure in the vicinity of the end face 121, it is possible to ensure a wide effective illumination area of the illumination device even if luminance unevenness is greatly generated in the vicinity of the optical structure.

  Since the recesses 125 and 127 are formed on the back surface 123 of the light guide member 120, the front surface 122 can be configured to be flat even in the formation region of the recess. For this reason, since it is not so difficult to configure so that the luminance of the recessed portion formation region hardly changes compared with the surroundings, it is also possible to illuminate by emitting light from the recessed portion formation region. In contrast to the configuration of the present embodiment, a recess may be formed on the surface 122.

  The light guide member 120 can be integrally formed by molding such as an injection molding method using a resin material. Moreover, it is also possible to form a hole or a recessed part by giving post-processes, such as a cutting process, with respect to the base material which does not have said hole or recessed part.

  In the present embodiment as well, on the back surface 123 of the light guide member 120, the internal propagation light is gradually deflected to the surface side while being propagated and emitted from the surface of the light guide member 170. Light diffusing means (not shown) is formed. The light diffusing means is formed on the back surface 123 in a mode (density or shape) according to the light amount distribution of the internally propagating light propagating through the light guide member 120. More specifically, the light diffusing means is, for example, a concavo-convex structure (prism) formed on the back surface 123, a printing pattern, a reflection pattern, or the like.

[Second Embodiment: Lighting Device]
Next, a second embodiment of the illumination device according to the present invention will be described with reference to FIG. In this embodiment, the optical structure of the light guide member 140 is only different from that of the first embodiment, and the description of the same part is omitted.

  In this embodiment, the light sources 111 and 112 are respectively arranged at positions relatively close to both ends in the width direction of the end surface 141 of the light guide member 140, whereby the width direction interval between the light sources 111 and 112 is the first embodiment. It is configured wider than the interval. A hole or recess 144 is formed in the front area in the optical axis direction of these light sources 111 and 112. The hole or recess 144 includes an inner surface 144a that is a reflective surface similar to that of the first embodiment. In addition, a hole or a recess 145 is formed in a region that is laterally removed from the front region in the optical axis direction of the light source. Similarly to the first embodiment, the hole or recess 145 also includes an inner surface 145a that is an opposing reflection surface facing the inner surface 144a.

  In this embodiment, the opening cross section of the hole or recess 145 is formed to be smaller than that of the hole or recess 144, and instead, the hole or recess 145 is in the optical axis direction of the light source (the vertical direction in the drawing) and the light guide member 140. Are arranged at positions shifted in the width direction (the left-right direction in the figure). Accordingly, the internally propagated light reflected by the inner surface 144a is incident on the inner surface 145a of the hole or recess 145 arranged at a different position according to the reflection direction, and the light guide member 140 in the width direction. It is reflected at different positions and propagates substantially in the direction of the optical axis. Therefore, since the internally propagated light can be dispersed in a wider area outside the front area in the optical axis direction of the light source, the light can be guided even if the number of light sources is small or the distance between the light sources is large. The light amount distribution in the width direction of the member 140 can be further relaxed, and a more uniform luminance distribution can be obtained on the surface of the light guide member 140.

[Third Embodiment: Lighting Device]
Next, a third embodiment of the lighting device according to the present invention will be described with reference to FIG. In this embodiment, only the optical structure of the light guide member 150 is different from that of the first embodiment, and thus the description of the same part is omitted.

  In this embodiment, the holes or recesses 154, 155, and 156 formed inside the light guide member 150 have a planar shape different from that of the first embodiment. The holes or recesses 154 and 155 have a “K” or “L” planar shape, and the holes or recesses 156 have an “I” planar shape. In this way, the planar shape of the hole or recess is such that the inner surface 154a to be the reflecting surface constituted by a part of the inner surface of the hole or recess or the inner surfaces 155a and 156a to be the opposing reflecting surface side the internal propagation light. The shape of the other inner surface portion is arbitrary as long as it can be reflected in the direction, and various shapes can be adopted thereby.

[Fourth Embodiment: Lighting Device]
Next, with reference to FIG. 5, 4th Embodiment of the illuminating device based on this invention is described. In this embodiment, only the optical structure of the light guide member 160 is different from that of the first embodiment, and thus the description of the same part is omitted.

  In this embodiment, a hole or recess 164 having a substantially circular planar shape is formed in the front area in the optical axis direction of the light sources 111 and 112. In addition, holes or recesses 165 and 166 having a planar shape similar to that of the third embodiment are formed in a region deviated laterally with respect to the front region. Of the internally propagating light generated based on the light emitted from the light sources 111 and 112, the light incident near the center of the hole or recess 164 passes through the hole or recess 164 and enters the light guide member 160 again. It enters and propagates in the front area. Light incident on the left and right peripheral portions of the hole or recess 164 is totally reflected laterally at an inner surface 164a (a semi-cylindrical portion on the light source side) that is a part of the inner surface of the hole or recess 164. The reflected light is reflected again by the inner surfaces 165a and 166a of the holes or recesses 165 and 166 disposed at the reflection destination, and propagates substantially in the optical axis direction.

  As described above, the reflecting surface may be formed as a flat surface as in the first to third embodiments described above, but a semi-cylindrical surface or the like like the inner surface 164a of the present embodiment. You may be comprised by various curved surfaces. The reflecting surface is not limited to the above-described cylindrical surface, but may be configured by various curved shapes such as a conical surface, a parabolic surface, and a hyperboloid, but a surface orthogonal to the surface of the light guide member (on the surface). Internally propagated light that propagates substantially parallel to the surface of the light guide member 160, such as a cylindrical surface having an axis in an orthogonal direction, an elliptical cylindrical surface, or the like, a surface extending linearly in a direction orthogonal to the surface. Can be deflected in other directions substantially parallel to the surface.

[Fifth Embodiment: Lighting Device]
Next, with reference to FIG. 6, 5th Embodiment of the illuminating device based on this invention is described. In this embodiment, since the optical structure of the light guide member 170 is only different from that of the first embodiment, description of the same part is omitted.

  In this embodiment, each inner surface 174a, 175a, 176a formed in a hole or recess 174, 175, 176 provided in the light guide member 170 is a curved surface. As in the fourth embodiment, it is preferable that these curved surfaces are configured with surfaces orthogonal to the surface of the light guide member.

  In this embodiment, the planar shape of the hole or recess 174 disposed in the front region in the optical axis direction of the light sources 111 and 112 is a substantially semicircular shape, and the inner surface 174a functioning as a reflecting surface is the hole or recess 174. It is composed of a semi-cylindrical surface portion. As described above, even when the inner surface serving as the reflection surface is curved, the shape of the holes or the recesses other than the inner surface 174a is arbitrary, and various shapes can be adopted.

  In addition, holes or recesses 175 and 176 are formed in a region deviated laterally from the front region in the optical axis direction of the light sources 111 and 112, and a concave curved surface constituting an opposing reflecting surface facing the reflecting surface. The inner surfaces 175a and 176a having a shape are formed.

  In this embodiment, the internally propagated light generated by the light emitted from the light sources 111 and 112 entering the light guide member 170 from the end surface 171 is not before encountering the holes or the recesses 174, 175, and 176. It propagates as a diffused light beam spreading in a fan shape, but a part of the light component contained in the diffused light beam is deflected to a light component substantially parallel to the optical axis direction by the optical system constituted by the inner surfaces 174a, 175a, 176a. It has come to be. That is, a part of the diffused light beam emitted from the light sources 111 and 112 is configured to be a substantially parallel light beam by the optical system.

  As described above, in the present embodiment, the optical system including the inner surface 174a that is the reflecting surface and the inner surfaces 175a and 176a that are the opposing reflecting surfaces disposed inside the light guide member 170 is the internal propagation light. Has a function of condensing the propagation direction of the light in the direction of the optical axis and reducing variations in the propagation direction of the internal propagation light. For this reason, by reducing the variation in the propagation direction of the internal propagation light, it is possible to more effectively exert the diffusion effect of the internal propagation light by the above-mentioned light diffusion means, and as a result, the luminance of the lighting device The distribution can be made uniform at a higher level.

[Sixth embodiment: lighting device]
Next, with reference to FIG. 7, 6th Embodiment of the illuminating device based on this invention is described. In this embodiment, since the other structures of the light guide member 180 are the same as those of the fifth embodiment except for the light diffusing means, description of the same parts is omitted.

  In this embodiment, the light diffusing means 183 a is formed on the back surface 183 of the light guide member 180. The light diffusing means 183a is constituted by grooves or ridges that are substantially parallel to the width direction of the light guide member 180 (the horizontal direction in FIG. 7A and the direction orthogonal to the paper surface in FIG. 7B). It has an uneven prism structure. The light diffusing means 183a having the concave and convex prism structure gradually deflects the internally propagated light propagating in the light guide member 180 in the optical axis direction of the light sources 111 and 112 toward the surface 182 side, and the deflected light is reflected on the surface. 182 has a function of illuminating light emitted with a small emission angle. In particular, the light diffusion means 183a is formed with an inclined optical surface 183b configured to deflect (reflect) the internally propagated light toward the surface 182 side, and the inclined optical surface 183b allows the internally propagated light to be emitted from the surface 182 at a low output. The light is emitted at the corner. The inclined optical surface 183b faces the optical axis direction (that is, the projected image on the surface 182 of the normal line of the inclined optical surface 183b is parallel to the optical axis direction), and is inclined toward the surface 182 side. It has become a surface.

  In the present embodiment, similarly to the fifth embodiment, the internal propagation light is guided when viewed in a plane by the optical system constituted by the inner surfaces 184a, 185a, 186a of the holes or recesses 184, 185, 186. At the same time as the light member 180 is diffused in the width direction, it is deflected so that its propagation direction is aligned with the optical axis direction of the light sources 111 and 112. Therefore, compared with the case where the optical system is not provided, The proportion of internally propagating light propagating in the near direction is high.

  On the other hand, the inclined optical surface 183b of the light diffusing unit 183a faces the direction in which the propagation direction of the internal propagation light is aligned by the optical system as described above (in the present embodiment, the optical axis direction of the light source). Therefore, when the internally propagating light is incident on the tilted optical surface 183b, the deflection direction (reflection direction) is less likely to greatly warp in the width direction of the light guide member 180. For this reason, since the outgoing angle of the illumination light that is deflected (reflected) by the inclined optical surface 183b and emitted from the light guide member 180 can be reduced, the condensing function of the illumination light is enhanced. Ratio of light components that can be effectively used as illumination light out of the amount of light emitted from the light guide member 180, that is, light components that do not contribute to illumination of the illumination target due to a relatively large emission angle with respect to the surface 182 Can be increased.

[Seventh Embodiment: Lighting Device]
Next, a seventh embodiment of the lighting device according to the present invention will be described with reference to FIG. In this embodiment, since the optical structure of the light guide member 120 is the same as that of the first embodiment, the same portions are denoted by the same reference numerals, and the description thereof is omitted.

  This embodiment differs from the first embodiment in that a light reflecting material 128 is disposed on the inner surfaces 124a and 125a. The light reflecting material 128 is, for example, a thin film made of various metals such as aluminum, chromium, silver, and an alloy, a paste in which fine particles made of a light reflective material such as metal fine particles are dispersed, and a light reflective material such as metal fine particles. It can be constituted by a resin material or the like in which fine particles made of a functional material are dispersed. The thin film can be formed on the inner surface by a vapor deposition method, a sputtering method, a coating method, etc., the paste can be placed on the inner surface by a coating method, and the resin material is adhered to the inner surface using an optical adhesive or the like. Or can be adhered and fixed by other means.

  In this embodiment, the internal propagation light is not reflected by using the total reflection using the refractive index of the light guide member 180. Therefore, the internal propagation light hardly depends on the incident angle of the internal propagation light and is laterally increased. Can be reflected. Therefore, the optical design composed of the reflecting surface and the opposing reflecting surface becomes easy, and a higher light deflection action can be realized with certainty.

[Eighth Embodiment: Lighting Device]
Next, with reference to FIG. 9, 8th Embodiment of the illuminating device based on this invention is described. In this embodiment, since the optical structure of the light guide member 150 is the same as that of the third embodiment, the same parts are denoted by the same reference numerals, and description thereof is omitted.

  This embodiment differs from the third embodiment in that a light reflecting material 158 is disposed on the inner surfaces 154a, 155a, 156a. The light reflecting material 158 is the same as that described in the seventh embodiment. This embodiment is different from the seventh embodiment in that the light reflecting material 158 is almost completely filled in the holes or the recesses 154, 155, and 156. In this case, it is preferable to use a paste-like material as the light reflecting material 158 and to fill and solidify the holes or recesses 154, 155 and 156 by using a dispenser or by a printing method or the like.

  Also in this embodiment, the inner surfaces 154a, 155a, and 156a can be configured to have a reflection surface and an opposing reflection surface having almost perfect reflection characteristics that hardly depend on the incident angle of the internal propagation light.

[Ninth embodiment: electro-optical device]
Next, a ninth embodiment of the electro-optical device according to the invention will be described with reference to FIG. FIG. 10 is a schematic longitudinal sectional view schematically showing a liquid crystal device 200 which is an embodiment of the electro-optical device of this embodiment. This embodiment includes the illumination device 100 as a backlight. In the liquid crystal device 200, the liquid crystal panel 220 and the lighting device 100 of the first embodiment are supported by a common support member 190.

  In the liquid crystal panel 220, the first substrate 221, the second substrate 222 having a projecting portion 222 a that projects in a plane from the outer shape of the first substrate 221, and the first substrate 221 and the second substrate 222 are provided. A panel structure is constituted by the sealing material 223 provided at the peripheral edge of the substrate for bonding. In the space formed by the first substrate 221, the second substrate 222, and the sealant 223, a liquid crystal 224 such as STN liquid crystal (Super Twisted Nematic) is enclosed as an electro-optical material. A first polarizing plate 225 and a second polarizing plate 226 are disposed on the outer surfaces of the first substrate 221 and the second substrate 222.

  The first substrate 221 and the second substrate 222 have stripe-shaped first transparent electrodes 229a and second transparent electrodes made of a plurality of ITO (Indium Tin Oxide) films on opposite surfaces. 229b is provided. An alignment film (not shown) made of polyimide resin or the like is formed so as to cover the first transparent electrode 229a and the second transparent electrode 229b, respectively. Here, the first transparent electrode 229a and the second transparent electrode 229b are provided so as to intersect each other, and a pixel is formed by the intersecting portion of the opposing first transparent electrode 229a and the second transparent electrode 229b and the liquid crystal 224 sandwiched therebetween. Is configured. With such a configuration, the liquid crystal panel 220 can change the alignment state of the liquid crystal 224 by selectively changing the voltage applied to each pixel, thereby changing the optical characteristics independently for each pixel. Can be made.

  The liquid crystal panel 220 is provided with an effective display area B in which the pixels are arranged. The effective display area B is configured to be included in a plane within the effective illumination area A of the illumination device 100. Is done. Here, the effective display area B of the liquid crystal panel 220 may be substantially coincident with the effective illumination area A.

  An electronic component (semiconductor IC chip) 227 is mounted on the overhanging portion 222a of the second substrate 222, and is electrically connected to the first transparent electrode 229a and the second transparent electrode 229b. A substrate 228 is also mounted on the overhanging portion 222a, and the substrate 228 is conductively connected to the electronic component 227 through a pattern on the overhanging portion 222a.

  In the present embodiment, the light sources 111 and 112 (112 is not shown) of the illumination device 100 are mounted on the substrate 228 described above. The substrate 228 extends from above the protruding portion 222 a of the liquid crystal panel 220 to the back of the liquid crystal panel 220, extends to the vicinity of the light guide member 120 of the lighting device 100, and is formed on the end surface 121 that is a light incident surface of the light guide member 120. Light sources 111 and 112 are mounted at the facing positions.

  In this embodiment, a video signal and a power supply potential are supplied to the liquid crystal panel 220 from an external circuit (not shown) to the terminal portion 228a of the substrate 228, and illumination power to the light sources 111 and 112 is supplied. Accordingly, the single substrate 228 is configured to be able to supply required power to the liquid crystal panel 220 and the lighting device 100 at the same time and to control the operation state thereof.

  In the ninth embodiment, since the light sources 111 and 112 of the lighting device 100 are mounted on the substrate 228 extending from the liquid crystal panel 220, it is necessary to provide a dedicated mounting substrate for the light sources 111 and 112. Therefore, the number of parts can be reduced and the whole can be made compact. However, instead of mounting the light sources 111 and 112 on the substrate 228 mounted on the liquid crystal panel 220 as described above, the light sources 111 and 112 may be mounted on a substrate different from the substrate 228.

  On the liquid crystal panel 220 side of the light guide member 120 of the lighting device 100, a diffusion plate 243 and prism sheets 244 and 245 are sequentially stacked. The diffusion plate 243 is for making the luminance of the display screen more uniform by diffusing the illumination light emitted from the illumination device 100. Also, the prism sheets 244 and 245 improve the light use efficiency by aligning the direction of the illumination light diffused by the diffusion plate 243 with the optical axis direction of the liquid crystal panel 220, and out of the light emitted from the liquid crystal panel 220. This is to increase the proportion of light components that contribute to display. Note that the illustrated adhesive sheet 260 (for example, a double-sided tape) is for bonding and fixing the liquid crystal panel 220 and the underlying structural portion to each other.

  In the present embodiment, power is supplied from the terminal portion 228 a and the light sources 111 and 112 are turned on via the substrate 228, so that the light emitted from the light sources 111 and 112 passes through the light guide member 120 and the light reflecting sheet 130. The light is emitted to the front side (upward in the drawing), passes through the diffusion plate 243, the prism sheets 244, 245, and the like, and enters the liquid crystal panel 220 as illumination light. On the other hand, in the liquid crystal panel 220, an appropriate drive signal is supplied to the first transparent electrode 229a and the second transparent electrode 229b via the electronic component 227 by supplying a video signal, a power supply potential, and the like via the wiring board 228. Applied. As a result, the optical characteristics of each pixel of the liquid crystal panel 220 are individually controlled, so that a predetermined display corresponding to the optical characteristics of each pixel is visually recognized on the front side of the liquid crystal device 200 by the illumination light emitted from the illumination device 100. The

  In this embodiment, the illumination device 100 of the first embodiment is used, but any of the illumination devices of the second to eighth embodiments can be used instead. Moreover, although the illuminating device 100 is arrange | positioned behind the liquid crystal panel 220 and is used as a backlight, the light reflection sheet 130 of these illuminating devices 100 is abbreviate | omitted, and sets the optical characteristic of a light guide member suitably. Therefore, it can be used as a front light disposed on the front side of the liquid crystal panel.

  In the ninth embodiment, the case where the liquid crystal panel is a simple matrix type liquid crystal device has been described. However, the present invention is not limited to this, and a TFT (Thin Film Transistor) or TFD (Thin Film Diode) is used. The present invention can also be applied to an active matrix liquid crystal device using a switching element such as a diode.

[Tenth embodiment: electronic device]
Finally, with reference to FIG.11 and FIG.12, embodiment of the electronic device which concerns on this invention is described. In this embodiment, an electronic apparatus including the electro-optical device (liquid crystal device 200) as a display unit will be described. FIG. 11 is a schematic configuration diagram showing an overall configuration of a control system (display control system) for the liquid crystal device 200 in the electronic apparatus of the present embodiment. The electronic device shown here includes a display control circuit 290 including a display information output source 291, a display information processing circuit 292, a power supply circuit 293, a timing generator 294, and a light source control circuit 295. The liquid crystal device 200 similar to the above is provided with a drive circuit 220D for driving the liquid crystal panel 220 having the above-described configuration. The drive circuit 220D is composed of the electronic component (semiconductor IC chip) 227 that is directly mounted on the liquid crystal panel 220 as described above. However, in addition to the above-described aspects, the drive circuit 220D may be a circuit pattern formed on the panel surface, or a semiconductor IC chip or a circuit pattern mounted on a circuit board conductively connected to the liquid crystal panel. Can be configured.

  The display information output source 291 includes a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), a storage unit such as a magnetic recording disk or an optical recording disk, and a tuning circuit that tunes and outputs a digital image signal. The display information is supplied to the display information processing circuit 292 in the form of an image signal or the like of a predetermined format based on various clock signals generated by the timing generator 194.

  The display information processing circuit 292 includes various known circuits such as a serial-parallel conversion circuit, an amplification / inversion circuit, a rotation circuit, a gamma correction circuit, and a clamp circuit, and executes processing of input display information to obtain image information. Are supplied to the drive circuit 220D together with the clock signal CLK. The drive circuit 220D includes a scanning line drive circuit, a signal line drive circuit, and an inspection circuit. The power supply circuit 293 supplies a predetermined voltage to each of the above-described components.

  The light source control circuit 295 supplies power supplied from the power supply circuit 293 based on a control signal introduced from the outside to the light source unit 110 including the light sources 111 and 112 of the illumination device 100 (specifically, the light source and the light source unit 295 are mounted thereon). Substrate 228). The light source control circuit 295 controls lighting / non-lighting of each light source of the light source unit 110 according to the control signal. It is also possible to control the luminance of each light source.

  FIG. 12 shows the appearance of a mobile phone which is an embodiment of the electronic apparatus according to the present invention. The electronic device 2000 includes an operation unit 2001 and a display unit 2002, and a circuit board 2100 is disposed inside the display unit 2002. The liquid crystal device 200 is mounted on the circuit board 2100. The liquid crystal panel 220 is configured to be visible on the surface of the display unit 2002.

  In the present embodiment, by using the liquid crystal device 200 for the display unit 2002 of the electronic device 2000, it is possible to achieve both the enlargement of the display unit 2002 or reduction in luminance unevenness and the size reduction of the electronic device 2000. .

  Note that the illumination device, electro-optical device, and electronic apparatus of the present invention are not limited to the illustrated examples described above, and can be variously modified without departing from the scope of the present invention. . For example, in the above embodiment, the inner surface of the light guide member is configured by a part of the inner surface of the hole or the recess, but a closed space (cavity) with a low light refractive index is provided inside the light guide member, Or it can comprise also by arrange | positioning the embedded object comprised with another raw material with a light refractive index smaller than the raw material which comprises a light guide member. In the latter case, for example, the light guide member can be formed by mixing a resin material having a small optical refractive index in an uncured resin base material and curing the base material as it is.

1 is a schematic cross-sectional view showing the configuration of a first embodiment of a lighting device according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view (a) and (b) showing an example of a sectional structure of a first embodiment. The schematic cross-sectional view which shows the structure of 2nd Embodiment of the illuminating device which concerns on this invention. The schematic cross-sectional view which shows the structure of 3rd Embodiment of the illuminating device which concerns on this invention. The schematic cross-sectional view which shows the structure of 4th Embodiment of the illuminating device which concerns on this invention. The schematic cross section which shows the structure of 5th Embodiment of the illuminating device which concerns on this invention. The schematic cross-sectional view (a) and schematic vertical cross-sectional view (b) which show the structure of 6th Embodiment of the illuminating device which concerns on this invention. The schematic cross-sectional view which shows the structure of 7th Embodiment of the illuminating device which concerns on this invention. The schematic cross section which shows the structure of 8th Embodiment of the illuminating device which concerns on this invention. FIG. 10 is a schematic cross-sectional view illustrating a configuration of a ninth embodiment of an electro-optical device according to the invention. The schematic cross-sectional view which shows the structure of 10th Embodiment of the electronic device which concerns on this invention. The perspective view of an electronic device. The schematic plan view of the conventional illuminating device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Illuminating device, 111, 112 ... Light source, 120 ... Light guide member, 121 ... End surface, 122 ... Front surface, 123 ... Back surface, 124 ... Hole, 124a, 125a, 126a, 127a ... Inner surface, 125 ... Recessed part, 126 ... Holes 127, recesses, 130, light reflecting sheets, 200, liquid crystal devices, 220, liquid crystal panels, 2000, electronic devices (mobile phones)

Claims (11)

In a lighting device having a light source and a light guide member that introduces light emitted from the light source at an end face and emits the light from the surface,
A reflection surface capable of reflecting at least a part of the internally propagated light of the light guide member laterally with respect to the incident direction is provided inside the light guide member and in a front region in the optical axis direction of the light source. A lighting device characterized by that. The lighting device according to claim 1, wherein the reflection surface is an inner surface configured to be able to totally reflect a part of the internal propagation light in the light guide member. The lighting device according to claim 1, wherein the reflection surface is configured on an inner surface of a hole formed in the light guide member. The lighting device according to claim 1, wherein the reflection surface is configured on an inner surface of a recess formed in the light guide member. 5. The apparatus according to claim 1, further comprising an opposing reflection surface that is disposed at a position deviated laterally from a front region in the optical axis direction of the light source and faces the reflection surface. Lighting device. The lighting device according to claim 5, wherein the reflecting surface and the opposing reflecting surface are configured to be substantially parallel to each other. The lighting device according to claim 6, wherein the two sets of the reflecting surface and the opposing reflecting surface are provided substantially symmetrically on both sides of the optical axis. 8. The reflection surface and the counter reflection surface have a function of reducing a variation in the propagation direction by converging the propagation direction of the internal propagation light in a predetermined direction. The lighting device described in 1. The lighting device according to claim 8, wherein an inclined optical surface is provided on a rear surface of the light guide member so as to face the predetermined direction and deflect the internal propagation light toward the front surface side. 10. An electro-optical device comprising: the illumination device according to claim 1; and an electro-optical panel configured to be able to display with illumination light of the illumination device. 11. An electronic apparatus comprising: the electro-optical device according to claim 10; and a control unit that controls the electro-optical device.

Images