JP4277752B2 - Video display device - Google Patents

Description

  The present invention relates to a video display device that provides a left and right eye with a virtual image of a displayed video superimposed on the observed external world while allowing the external world to be observed.

Personal video display devices that are worn on the head or held by hand and used in front of eyes are becoming widespread. Such a video display device is desirably small and lightweight, and generally includes a small display element and an observation optical system that provides an enlarged virtual image of the video displayed on the display element. Further, as proposed in, for example, Japanese Patent Application Laid-Open No. 2000-19450, the outside world can be observed through an observation optical system so as to be suitable for use in daily life.
JP 2000-19450 A

A personal video display apparatus can be configured to provide only one set of display elements and an observation optical system and provide an image (virtual image) only to the left eye or the right eye. Two sets may be provided to provide video to the left and right eyes. In a configuration in which two sets of display elements and an observation optical system are provided to provide images to the left and right eyes, the convergence is also made variable. For example, Japanese Patent Application Laid-Open No. 6-43446 proposes that the video display device is a glasses type and that the congestion is adjusted at the bridge portion.
JP-A-6-43446

  In a configuration including two sets of display elements and observation optical systems, a relative error may occur in the left and right optical axes due to manufacturing errors of parts, etc., in order to eliminate not only the convergence adjustment but also the optical axis error. In addition, it is preferable that the direction of the optical axis can be adjusted. An example of a conventional video display device capable of adjusting the direction of the optical axis is shown in FIGS.

  The video display apparatus of FIG. 12 adjusts the angle formed by the left and right optical axes by moving the observation optical system. In FIG. 12, 91L and 91R are display elements such as liquid crystal displays that display left and right images, 92L and 92R are lenses that form the left and right observation optical systems, and 93L and 93R are illumination lights that illuminate the display elements 91L and 91R. Light sources such as light emitting diodes, 94L and 94R are condensing lenses for uniformly guiding illumination light from the light sources 93L and 93R to the display elements 91L and 91R, and EL and ER are left and right optical pupils. In this example, the optical axis is adjusted by moving the lens 92L for the left eye by the distance δ1, and in order to be able to guide the light to the left optical pupil EL after the adjustment, the light beam diameter β1 is changed to the optical axis. Is larger than the light beam diameter α1 in the configuration in which is fixed.

  The video display apparatus of FIG. 13 adjusts the angle formed by the left and right optical axes by moving the display element. In FIG. 13, 95L and 95R are display elements such as a liquid crystal display for displaying left and right images, 96L and 96R are lenses forming left and right observation optical systems, and 97L and 98R are illumination lights for illuminating the display elements 95L and 95R. The emitted light sources, EL and ER are the left and right optical pupils. In this example, the optical axis adjustment is performed by moving the display element 95L for the left eye and the light source 97L by δ2, and in order to be able to guide the light to the left optical pupil EL even after the adjustment, the light beam diameter is again used. β2 is made larger than the light beam diameter α2 in the configuration in which the optical axis is fixed.

  By making it possible to adjust the relative orientations of the left and right optical axes in this way, even if there is a deviation in the position or orientation of the image provided to the left or right eye due to an error in parts accuracy, etc. Can be removed, and the video display device is suitable for use in daily life with less burden on the eyes of the user.

  However, the apparatus shown in FIG. 12 requires a mechanism for moving the lens and needs to ensure a large light beam diameter, so that the housing for accommodating the display element, the light source, etc. becomes larger and heavier. End up. In addition, an increase in the size of the housing narrows the range of the external world that can be observed (viewing angle), which hinders use in daily life. Furthermore, after the optical axis adjustment, the positional relationship between the lens and the display element is greatly deviated from the design value. As a result, the aberration is increased and the quality of the provided image is likely to be deteriorated.

  In the apparatus shown in FIG. 13, a mechanism for moving the display element and the light source is required, and the housing for accommodating these is also enlarged and heavy. In addition, the field of view of the outside world becomes narrow due to the increase in size of the housing. Furthermore, in order to ensure a large light beam diameter, the brightness of the provided image tends to decrease. There is also a problem that the positional relationship between the lens and the display element is greatly deviated from the design value, and the quality of the image is deteriorated due to aberration.

  In addition, although the above-mentioned JP-A-6-43446 refers to performing congestion adjustment, a specific configuration for adjusting congestion is not described. Moreover, since it is a structure of only the part corresponding to the image | video which the range of the external field which can be observed provides, it is not very suitable for use in daily life.

  The present invention has been made in view of the above problems, and provides a small and lightweight video display device capable of adjusting an optical axis without a large viewing angle of the external world and accompanied by a decrease in video quality. Objective.

To achieve the above object, a video display device according to a first aspect of the present invention is a video display device that provides video to the left and right eyes of an observer, and a left display unit that displays video to be provided to the left eye; The left housing that houses the left display unit and the left eye can be used to observe the outside world, and light from the left display unit is guided to the left eye, and a virtual image of the image displayed by the left display unit is observed. A left optical module composed of a left optical system provided over a part of the external world, a right display unit for displaying an image to be provided to the right eye, a right housing for housing the right display unit, and an external world for the right eye The right optical system is a right optical system that guides the light from the right display unit to the right eye and provides a virtual image of the image displayed by the right display unit over a part of the observed external environment. An optical module, a connecting portion connecting the left optical module and the right optical module, and the left optical module; Provided and between the connecting portion between the right optical module connecting portion, and the direction changing mechanism for the left optics module and orientation of the right optical module variable, by connecting the left optics module and right optical module, the connecting portion And a connection reinforcing part that absorbs the displacement of the left optical module and the right optical module by the orientation changing mechanism, and the connection part and the connection reinforcing part are provided for the left eye and the right eye when mounted on the head. The right and left optical modules are fixed so as to be sandwiched between the front and rear directions, and the variable direction mechanism defines two direction setting surfaces that respectively determine the directions of the left optical module and the right optical module with respect to the connecting portion. The angle of the direction setting surface is variable .

In the video display device according to the first aspect of the invention , the optical axis of the left optical module that provides video to the left eye and the optical axis of the right optical module that provides video to the right eye are adjusted by changing the orientation of the entire optical module. Do. Therefore, even if the optical axis is adjusted, the relative position between the display unit and the optical system included in each optical module does not vary. For this reason, it is possible to provide a high-quality image without generating aberrations, and it is not necessary to increase the beam diameter, and thus a bright image can be provided. Further, it is not necessary to house a mechanism for moving a display unit or a part of the optical system in the housing, and the housing is small and lightweight. It is possible to prevent the viewing angle of the outside world from being reduced by the housing. Since the direction changing mechanism defines two direction setting surfaces that respectively define the directions of the left optical module and the right optical module with respect to the connecting portion, and the angle of the direction setting surface is variable, the direction changing mechanism can be made smaller. It is possible to prevent the direction changing mechanism from affecting the viewing angle of the outside world. The left optical module and the right optical module are connected to reinforce the connection by the connecting portion, and the connection reinforcing portion that absorbs the displacement of the left optical module and the right optical module by the orientation changing mechanism is provided. By using a plurality of members, it is possible to reduce the size and weight while firmly fixing the left and right optical modules. In addition, since the connection reinforcing portion absorbs the displacement, it hardly affects the optical axis adjustment.

According to a second aspect of the present invention, there is provided the video display device according to the first aspect, wherein the direction changing mechanism includes a first surface in contact with the connecting portion, and a second surface that faces the first surface and is inclined with respect to the first surface. A first inclined plate-like member that is rotatable along the first surface, a first surface that is in contact with a second surface of the first inclined plate-like member, and a first surface The second inclined plate-shaped member has a second surface that is opposed and inclined with respect to the first surface, and is rotatable along the first surface. A direction setting surface is defined by the surface. In this configuration, by rotating the first and second inclined plate-like members individually, the direction of the optical module can be changed in an arbitrary direction, and the direction of the optical module is changed at the rotation angle of the inclined plate-like member. Since the amount of change is determined, the optical axis can be adjusted easily. Moreover, since there are few components and it is a simple shape, cost is suppressed and reliability is also improved.

According to a third aspect of the present invention, there is provided the video display device according to the first aspect, wherein the optical module and the connecting portion are screw-fixed, and the direction changing mechanism is a screw between the optical module and the connecting portion. It consists of the annular member penetrated by.

According to a fourth aspect of the present invention, there is provided the video display device according to the first aspect, wherein the direction changing mechanism is attached to the connecting portion so that the end portion protrudes toward the optical module. It consists of a screw.

  According to a fifth aspect of the present invention, there is provided the video display device according to the second aspect, wherein the second surface is inclined with respect to the first surface of the first inclined plate-like member and the first inclined plate-like member is the first. The inclination of the second surface with respect to the surface is equal. In this case, the first inclined plate-like member and the second inclined plate-like member are rotated in the same direction or in the opposite direction, and the optical module is oriented in one direction by rotating the same angle in the opposite direction. It becomes possible to change only to. Therefore, the optical axis adjustment becomes very easy.

According to a sixth aspect of the present invention, in the video display device according to any one of the first to fifth aspects, the direction changing mechanism changes the direction of the left optical module to the first direction, and changes the direction of the right optical module to the first direction. The first direction is changed to a second direction perpendicular to the first direction. If it does in this way, it will become easy to set the optical axis of a right-and-left optical module on the same plane, and to arbitrarily set the angle which both optical axes make on a plane.

The video display device according to a seventh aspect of the present invention is the video display device according to any one of the first to sixth aspects, wherein the left optical system and the right optical system totally reflect light from the left display unit and the right display unit, respectively. It includes a transparent plate-like member that travels and transmits light from the outside. The viewing angle of the outside world can be widened, and it is not necessary to use a semi-transmissive optical member such as a half mirror to guide the light from the display unit and the light from the outside world to the eyes. Can be kept dark.

The video display device according to an eighth aspect of the present invention is the video display device according to any one of the first to seventh aspects, wherein the left optical system and the right optical system respectively reflect light from the left display unit and the right display unit to provide a virtual image. And a volume phase hologram element. By using a volume phase hologram element having a feature of high transmittance, it is possible to avoid darkening the portion of the observed external world that overlaps the video (virtual image).

A video display device according to a ninth aspect of the present invention is the video display device according to any one of the first to eighth aspects, further comprising a mounting portion for mounting on the head of the observer, and the left optical when mounted on the head. wherein the module and the right optical module is positioned just before the left and right eyes, respectively. By providing the mounting part, it is possible to use both hands freely while observing the image, which is suitable for daily use.

According to a tenth aspect of the present invention, in the ninth aspect, the mounting portion includes a left temple that is attached to the left optical module and supported by the left head, and a right temple that is attached to the right optical module and supported by the right head. and right temple that features a glasses-type der Rukoto including a nose pad that is supported by the nose. If it does in this way, it will become an apparatus with easy attachment or detachment, and a direction change mechanism will not become easy to obstruct observation of the outside world.

  Since the image display apparatus of the present invention performs the optical axis adjustment by changing the orientation of the entire optical module, the relative position between the display unit and the optical system does not change even when the optical axis adjustment is performed, and it is surely bright and high quality. High image quality can be provided. Moreover, it is small and light, and has a large viewing angle of the outside world that can be observed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A video display device 1 according to the first embodiment is shown in FIG. In FIG. 1, (a) is a front view, (b) is a top view, and (c) is a side view. The video display device 1 has a generally symmetrical glasses shape as a whole, and is used by being mounted on the head of a user (observer). The video display device 1 provides video to both eyes of a user, and includes several pairs of components having the same function for providing video to the left and right eyes. In the following description, “L” or “R” indicating the left and right are added to the end with the same reference numeral, and the components constituting the pair are distinguished, and the same reference sign excluding “L” and “R” is used. , And represents the constituent elements that make up the pair.

  The video display device 1 guides the video light from the left and right housings 11L and 11R and the video display units 12L and 12R that accommodate the left and right video display units 12L and 12R (see FIG. 2) to the left and right eyes of the observer. Left and right observation optical systems 13L and 13R that provide images, and left and right transparent plates 14L and 14R joined to the observation optical systems 13L and 13R are provided. The housing 11L, the video display unit 12L, the observation optical system 13L, and the transparent plate 14L are integrated to form the left optical module 10L. The housing 11R, the video display unit 12R, the observation optical system 13R, and the transparent plate 14R are also included. The right optical module 10R is configured by being integrated.

  In addition to this, the video display device 1 includes a bridge 21 that connects the left and right optical modules 10L and 10R, left and right frames 22L and 22R fixed to the optical modules 10L and 10R, and frames 22L and 22R that are rotatable via hinges. Left and right temples 23L and 23R attached to the bridge 21, left and right nose pads 24L and 24R attached to the bridge 21, the left and right video display units 12L and 12R, a cable 15 for supplying power, control signals, and video signals, a cable 15 includes a control unit (not shown) that controls the operation of the video display units 12L and 12R. Note that the frames 22L and 22R are attached to the edges of the observation optical systems 13L and 13R that are not involved in providing images of the transparent plate 13a (FIG. 2) described later, and the bridge 21 is also the same.

  When mounted on the user's head, the temples 23L, 23R are supported by the left and right temporal regions, the nose pads 24L, 24R are supported by the sides of the nose, and the left and right observation optical systems 13L, 13R are The housings 11L and 11R are positioned immediately in front of the left and right eyes, respectively, and the transparent plates 14L and 14R are positioned below the observation optical systems 13L and 13R, respectively. Further, the bridge 21 is located immediately before the left and right eyes.

  The observation optical systems 13L and 13R and the transparent plates 14L and 14R can transmit light from the outside world and guide it to the eye. A user wearing the video display device 1 can observe the observation optical systems 13L and 13R or transparent. The outside world can be observed through the plates 14L and 14R. The observation optical systems 13L and 13R reflect the light from the video display units 12L and 12R to guide them to the optical pupils EL and ER, respectively, and provide an enlarged virtual image of the video represented by the light from the video display units 12L and 12R. The user can observe a virtual image that overlaps a part of the outside world under observation through the optical pupils EL and ER. The nose pads 24L and 24R can move in the left-right direction, and the left and right optical pupils EL and ER can be adjusted to the left and right eyes of the user by moving the nose pads 24L and 24R.

  FIG. 2 shows a cross section of the optical module 10 taken along line A-A ′ in FIG. The housing 11 includes a display element 12a that displays an image, a light source 12b that emits illumination light for illuminating the display element 12a, a diffusion plate 12c that diffuses illumination light from the light source 12b, and a light collection that collects the illumination light. A video display unit 12 including a lens 12d is accommodated. The display element 12a is a transmissive liquid crystal display, and modulates the applied illumination light with the displayed image to generate image light representing the image. The light source 12b is an RGB integrated light emitting diode.

  The diffusing plate 12c has anisotropy whose diffusivity varies depending on the direction, and diffuses the illumination light from the light source 12b so as to match the shape of the display element 12a which is a rectangle long in the left-right direction. The diffusion angle of light by the diffusion plate 12c is about 40 ° in the left-right direction and about 0.5 ° in the up-down direction. The condenser lens 12d is arranged so that the light diffused by the diffusion plate 12c transmits the display element 12a and efficiently forms the optical pupil E.

  The observation optical system 13 includes a transparent plate 13a and a volume phase hologram element 13b. The transparent plate 13a is made of a material having a high transmittance over the entire visible light wavelength band. The rear surface (surface close to the eye) of the transparent plate 13a is a flat surface, and the front surface (surface far from the eye) is also a flat surface except for the upper and lower portions, and is parallel to the rear surface. The upper part of the front surface of the transparent plate 13a is set so as to move away from the rear surface as it approaches the upper end, and the upper end portion of the transparent plate-like plate 13a has a wedge shape with a wide top. The casing 11 is fixed to the wedge-shaped part.

  The lower part of the front surface of the transparent plate 13a is set to approach the rear surface as it approaches the lower end, and intersects the rear surface at the lower end. That is, the lower part of the front surface is the lower end surface of the transparent plate 13a, and the lower end surface is inclined with respect to the rear surface. In addition, the thickness of the part except the upper part and the lower part of the transparent plate 13a is about 3 mm.

  The light from the display element 12a passes through the upper end surface of the transparent plate 13a, enters the inside of the transparent plate 13a, travels downward while being totally reflected by the rear and front surfaces of the transparent plate 13a, and the lower end surface of the transparent plate 13a. To reach.

  The volume phase hologram element 13b is affixed to the lower end surface of the transparent plate 13a, reflects light from the display element 12a incident through the inside of the transparent plate 13a by diffraction, and from the rear surface of the transparent plate 13a. In addition, the optical pupil E is set so that an enlarged virtual image of the image represented by the light can be observed. The distance from the optical pupil E to the virtual image is, for example, 1 m.

  In general, since a hologram element is an element using light diffraction, it has high wavelength selectivity and acts only on light having a wavelength width of about 20 nm centered on a design wavelength. In the video display device 1, the center wavelengths of the R, G, and B illumination lights emitted from the light source 12b are set to 465 nm, 520 nm, and 635 nm. Therefore, the center wavelengths of the video light also have these values. The volume phase hologram element 13b is produced by exposing the hologram photosensitive material with light of these wavelengths, and the wavelengths of light reflected by the volume phase hologram element 13b are 465 ± 10 nm, 520 ± 10 nm, and 635 ±. 10 nm. Light from the outside world passes through the volume phase hologram element 13b except for these wavelength bands.

  The aforementioned transparent plate 14 is for preventing refraction of light from the outside at the inclined lower end surface of the transparent plate 13a of the observation optical system 13, and is joined to the lower end surface of the transparent plate 13a. A parallel plate is comprised with 13a. The volume phase hologram element 13b is sandwiched between the transparent plate 13a and the transparent plate 14. The transparent plate 14 is made of the same material as the transparent plate 13a, and the refractive indexes of both are equal.

  The observation optical system 13 configured as described above can guide the light from the display element 12a to the optical pupil E without loss, and can provide a bright image. Moreover, since the observation optical system 13 and the transparent plate 14 transmit almost all of the light from the outside, the outside to be observed is bright. Here, the image (virtual image) is observed so as to overlap a part of the outside world, but in order to make the image easier to observe, a part of the light from the outside world is blocked and the light is blocked. The video may overlap the part.

  The housing 11 is set to a minimum size sufficient to accommodate the video display unit 12 and its drive circuit (not shown), and is disposed so as to be directed forward and upward from the upper end of the transparent plate 13a. Has been. Therefore, the range of the outside world blocked by the housing 11 is narrow. FIG. 3 shows the field of view of the outside world. In FIG. 3, the shaded area is a portion blocked by the casing 11, and the vertical angle is about 30 °. In the video display apparatus 1, the viewing angle of the outside world is about 70 ° in the vertical direction and about 90 ° in the horizontal direction. The viewing angle of the video (virtual image) is about 10 ° in the vertical direction and about 14 ° in the horizontal direction.

  The field of view of the outside world is also blocked by the bridge 21 and the frames 22L and 22R, but the range blocked by these is narrow, and in the image display device 1, observation is performed without using the observation optical systems 13L and 13R and the transparent plates 14L and 14R. If the range is included, 80% or more of the normal field of view (field of view when the video display device 1 is not mounted) is secured.

  Between the bridge 21 and the left and right optical modules 10L, 10R, there is provided a variable direction mechanism for changing the direction of each of the optical modules 10L, 10R. By changing the directions of the optical modules 10L and 10R, the directions of the optical axes AXL and AXR can be adjusted.

  FIG. 4 shows the direction changing mechanism 25 of the left optical module 10L and its periphery. 4, (a) is a front view, and (b) and (c) are sectional views taken along lines B-B 'and C-C' of (a), respectively. The direction changing mechanism 25 is composed of two plate-like members 25a and 25b that are circular when viewed from a direction substantially perpendicular to the two surfaces that are opposed to each other (that is, non-parallel). These two inclined plate-like members 25a and 25b have the same degree of inclination. On the rear surface of the bridge 21, a circular recess 21a as viewed from the front is formed in the vicinity of the end near the left optical module 10L. Yes.

  The front surface of the inclined plate member 25a (the lower surface with respect to the concave portion 21) is in contact with the bottom surface of the concave portion 21a, and the rear surface of the inclined plate member 25a and the front surface of the inclined plate member 25b are in contact with each other. The depth of the recess 21a is smaller than the thickness of the inclined plate members 25a and 25b, and the rear portion of the inclined plate member 25b slightly protrudes from the recess 21a. The front surface of the edge of the transparent plate 13a of the left observation optical system 13L is in contact with the rear surface of the inclined plate-like member 25b protruding from the recess 21a. The direction of the transparent plate 13a (the direction of the left optical unit 10L) is determined by the direction of the rear surface of the inclined plate member 25b.

  The bridge 21 is formed with two screw receiving holes 21b above and below the recess 21a, and the edge of the transparent plate 13a of the left observation optical system 13L is a position corresponding to the two screw receiving holes 21b. In addition, two through holes 13c for inserting the screws 26 are formed. In addition, a pressing plate 27 having a through hole 27a formed at a position corresponding to the two screw receiving holes 21b is disposed so as to be in contact with the rear surface of the transparent plate 13a. With the front surface of the transparent plate 13a in contact with the rear surface of the inclined plate-like member 25b, the screw 26 is engaged with the screw receiving hole 21b of the bridge 21 through the through hole 27a of the holding plate 27 and the through hole 13c of the transparent plate 13a. The transparent plate 13 a is fixed to the bridge 21 by lightly tightening.

  The holding plate 27 is for correcting the inclination of the transparent plate 13a with respect to the screw 26 and bringing the transparent plate 13a into close contact with the rear surface of the inclined plate-like member 25b. The front surface in contact with the transparent plate 13a is provided with a convex portion 27b. It has been. The front surface of the pressing plate 27 is in contact with the transparent plate 13 a at the convex portion 27 b and the opposite side, and the entire rear surface of the pressing plate 27 is in contact with the head of the screw 26. A convex portion 21 c is also provided in the vicinity of the screw hole 21 b on the rear surface of the bridge 21. The convex portion 21 c is for preventing the transparent plate 13 a from being unnecessarily sinked and tilted by one screw 26 when the screw 26 is tightened.

  In the state where the screw 27 is removed, the inclined plate-like members 25a and 25b can rotate in the recess 21a. By rotating the inclined plate members 25a and 25b, the inclination direction of the rear surface of the inclined plate member 25b is changed, and the direction of the left optical module 10L determined by the rear surface of the inclined plate member 25b is also changed. The left optical module 10L can be directed in an arbitrary direction by individually rotating the two inclined plate members 25a and 25b.

  As described above, the orientation changing mechanism 25 can set the orientation of the left optical module 10L in an arbitrary direction. However, in the video display device 1, the orientation of the left optical module 10L is set in the left-right direction (x in FIG. 4A). The direction of the right optical module 10R is changed only in the vertical direction as will be described later. The convex part 27b of the pressing plate 27 and the convex part 21c of the bridge 21 are provided at positions suitable for changing the direction of the left optical module 10L in the left-right direction.

  A method for setting the orientation of the left optical module 10L will be described with reference to FIG. 5A to 5C, the front view of the direction changing mechanism 25 is shown at the bottom and the top view is shown at the top, and FIG. 5A also shows a side view.

  First, the two inclined plate-like members 25a and 25b are set so as to be inclined in the vertical direction (the y-axis direction in FIG. 4A) and the inclination directions are opposite to each other. FIG. 5A shows this state. At this time, the front surface of the inclined plate member 25a and the rear surface of the inclined plate member 25b are parallel to each other.

  From this state, when the inclined plate members 25a and 25b are rotated by 45 ° in opposite directions, the state shown in FIG. 5B is obtained. Assuming that the angle formed by the two opposing surfaces of the inclined plate members 25a and 25b is θ, the angle formed by the front surface of the inclined plate member 25a and the rear surface of the inclined plate member 25b is the left-right direction (x-axis direction). Is θ × √2 (square root of 2), and 0 in the vertical direction (y-axis direction). Here, the angle between the front surface of the inclined plate-like member 25a and the rear surface of the inclined plate-like member 25b becomes zero in the vertical direction because the rotation directions of the inclined plate-like members 25a and 25b are opposite and the rotation amount is the same. This is because the inclinations of the two are canceled out.

  When the inclined plate members 25a and 25b are rotated 90 ° in the opposite directions from the state shown in FIG. 5A, the state shown in FIG. 5C is obtained. At this time, the angle formed by the front surface of the inclined plate-like member 25a and the rear surface of the inclined plate-like member 25b is the maximum θ × 2 in the left-right direction (x-axis direction) and is 0 in the vertical direction (y-axis direction). It becomes.

  That is, by rotating the inclined plate-like members 25a and 25b in the opposite directions by the same angle, the change in the direction of the left optical module 10L can be limited to one direction. By adjusting the rotation angle, the left optical module 10L The amount of change in direction can be arbitrarily set in the range from 0 to the maximum θ × 2.

  FIG. 6 shows the direction changing mechanism 28 of the right optical module 10R and its periphery. 6A is a side view, and FIG. 6B is a front view. The direction changing mechanism 28 includes an annular member 28a. The right optical module 10 </ b> R is provided with two through holes in an edge portion that is not involved in providing an image of the transparent plate 13 a of the right observation optical system 13 </ b> R, a screw 29 is passed through these through holes, and a screw receiving hole provided in the bridge 21 is screwed. It is fixed to the bridge 21 by engaging 29 and lightly tightening. The annular member 28 a is inserted through one screw 29 and is positioned between the transparent plate 13 a and the bridge 21. The two screws 29 are arranged side by side in the vertical direction (y-axis direction in FIG. 6B).

  The front surface of the transparent plate 13 a is in contact with the lower end portion of the rear surface of the bridge 21 and the lower end portion of the annular member 28 a in contact with the bridge 21, and is inclined with respect to the rear surface of the bridge 21. That is, as shown in FIG. 7, the annular member 28a, together with the bridge 21, defines a plane 28p that defines the direction of the transparent plate 13a of the right observation optical system 13R (the direction of the right optical module 10R), and the thickness of the annular member 28a. The angle θ ′ formed by the rear surface of the bridge 21 and the plane 28p is determined by t. By using the annular member 28a having a different thickness t, the amount of change in the direction of the right optical module 10R can be arbitrarily set. Since the lower end portion of the bridge 21 in contact with the transparent plate 13a and the lower end portion of the annular member 28a are arranged in the vertical direction, the direction of the right optical module 10R can be changed only in the vertical direction.

  Instead of using one annular member 28a having an appropriate thickness, a plurality of annular members 28a are used in an overlapping manner so that the total thickness t is adjusted by the number and individual thickness of the annular members 28a. It may be. In addition, here, an example is shown in which the upper one of the two screws 29 is inserted into the annular member 28a, but the lower one of the two screws 29 may be inserted into the annular member 28a.

  A modification of the direction changing mechanism 28 is shown in FIG. The direction changing mechanism 28 includes two screws 28b attached to the bridge 21 so that the end portion protrudes rearward (transparent plate 13a side). These screws 28b are provided side by side in the vertical direction. By changing the protruding amount of the two screws 28b, the direction of the right optical module 10R can be arbitrarily changed in the vertical direction.

  As described above, the orientation variable mechanism 25 is configured to change the orientation of the left optical module 10L only in the left-right direction, and the orientation variable mechanism 28 is configured to change the orientation of the right optical module 10R only in the vertical direction. It is easy to adjust the relative orientations of the optical axes of the modules 10L and 10R. Even when the optical axes of the left and right optical modules 10L and 10R are in a twisted positional relationship, the right and left optical modules 10L can be adjusted by adjusting the orientation of the right optical module 10R by the orientation variable mechanism 28. The optical axis of 10R can be positioned on the same plane, and the orientation of the left optical module 10L is adjusted by the orientation variable mechanism 25 in this state, so that the angle formed by the optical axes of the left and right optical modules 10L and 10R can be adjusted. It can be arbitrarily determined. For example, if the angle formed by the left and right optical axes is set to 3.5 °, the convergence angle for observing an image about 1 m ahead is obtained.

  If another screw 28b is added to the direction changing mechanism 28 shown in FIG. 8 so that the three screws 28b are not located on the same straight line, the direction of the right optical module 10R can be changed to an arbitrary direction. Is also possible.

  In the video display device 1, in order to adjust the optical axes of the left and right optical modules 10 </ b> L and 10 </ b> R, the relative positions of the video display unit 12 and the observation optical system 13 are changed in order to change the orientation of the optical modules 10 </ b> L and 10 </ b> R. There is no need. Accordingly, it is possible to provide a high-quality image with less occurrence of aberration. In addition, since it is not necessary to increase the diameter of the light beam from the image display unit 12, it is possible to provide a bright image, and the transparent plate 13a of the observation optical system 13 can be thinned, which is small and light. It becomes the device of. Furthermore, since the direction variable mechanisms 25 and 28 are small in size, it is difficult to affect the external viewing angle, and a wide viewing angle can be secured.

  The video display apparatus 2 of 2nd Embodiment is demonstrated. This video display device 2 is obtained by modifying the video display device 1 of the first embodiment to more firmly fix the left and right optical modules 10L, 10R. Other configurations are the same as those of the video display device 1, and the same components are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 9 shows the periphery of the bridge 21 that connects the left and right optical modules 10L and 10R. 9A is a front view, and FIG. 9B is a top view. A second bridge 30 is provided behind the bridge 21. The second bridge 30 is shown in FIG. 10A is a front view, FIG. 10B is a top view, and FIG. 10C is a side view. The second bridge 30 has an “H” shape when viewed from the front, and is fixed to the edges of the transparent plates 13a of the left and right observation optical systems 13L and 13R by screws 31 at the upper and lower ends of the left and right ends. ing. In addition, the center part of the 2nd bridge | bridging 30 is made into the shape bent forward in the middle so that it may not contact a user's nose.

  Thus, by connecting the left and right optical modules 10L and 10R with a plurality of members, fluctuations in the direction of the optical axis of the optical modules 10L and 10R during use can be suppressed. In particular, since the bridge 21 fixes the left and right optical modules 10L and 10R from the front, the second bridge 30 fixes the left and right optical modules 10L and 10R from the rear, so that the optical axes of the optical modules 10L and 10R are fixed. Strong against the force that tilts left and right. For example, when a force to spread the left and right temples 23L and 23R (see FIG. 1) is applied, the optical axes of the left and right optical modules 10L and 10R tend to tilt so that the front faces inward. It can be suppressed.

  The width (size in the vertical direction) in the vicinity of both ends of the horizontal portion of the second bridge 30 is set to be smaller than that of the central portion. The narrow portion 30a is more easily bent back and forth and more easily twisted than other portions. In the adjustment of the orientation by the orientation variable mechanisms 25 and 28, the positions and orientations of the left and right optical modules 10L and 10R slightly change. However, the displacement shown by the arrow D1 in FIG. When displacement as indicated by the arrow D2 occurs, the narrow portion 30a bends or twists so that the displacement can be absorbed. For this reason, the second bridge 30 does not hinder the fixing of the optical modules 10L and 10R after the orientation adjustment by the orientation variable mechanisms 25 and 28 to the bridge 21.

  The second bridge 30 is made of metal, and is strong against compression and expansion including the narrow portion 30a. Therefore, the function of suppressing the tilting of the optical axes of the optical modules 10L and 10R in the left-right direction during use is high.

  An optical module 10 of the video display device 3 of the third embodiment is shown in FIG. This video display device 3 is different from the first and second video display devices 1 and 2 in the configuration of the video display unit 12 and the observation optical system 13. The video display unit 12 includes a display element 12a formed of a liquid crystal display, and a light source 12b in which a light emitting diode and a light guide plate are combined. The observation optical system 13 includes a transparent plate 13a having a curved front surface (surface far from the eye) and a rear surface (surface close to the eye), and a volume phase hologram element 13b provided on the front surface of the transparent plate 13a.

  The light from the display element 12a enters the transparent plate 13a from the upper end surface, is totally reflected on the rear surface, and reaches the hologram element 13b. The hologram element 13b is set so that light is reflected by diffraction and emitted from the rear surface of the transparent plate 13a, and an enlarged virtual image of the image represented by the light can be observed on the optical pupil E. A transparent plate 14 is bonded to the front surface of the transparent plate 13a of the observation optical system 13, and the front surface of the transparent plate 14 is not distorted in the external environment observed through the transparent plate 13a and the transparent plate 14. In order to do so, it is a curved surface corresponding to the rear surface of the transparent plate 13a.

  The light from the display element 12a is only totally reflected once on the rear surface of the transparent plate 13a until it reaches the hologram element 13b, and does not enter the front surface (joint surface with the transparent plate 14) of the transparent plate 13a. Therefore, light representing an image is not lost through the transparent plate 14. The front and rear surfaces of the transparent plates 13a and 14 can be spherical or free curved surfaces.

  The configuration of the video display device 3 excluding the video display unit 12 and the observation optical system 13 is the same as that of the video display device 1 of the first embodiment or the video display device 2 of the second embodiment. However, the adjustment of the optical axes of the left and right optical modules 10L and 10R is performed by changing the orientation of the entire optical modules 10L and 10R.

  In each of the above embodiments, the direction changing mechanism 25 for the left optical module 10L and the direction changing mechanism 28 for the right optical module 10R are configured differently. However, as the direction changing mechanism of the left and right optical modules 10L, 10R. It is also possible to adopt the same configuration, for example, the direction changing mechanism 25. Here, the directions of the left and right optical modules 10L and 10R are changed to only one direction, but the directions of the optical modules 10L and 10R may be changed to arbitrary directions. When this is realized by the orientation variable mechanism 25, the inclinations of the two inclined plate members 25a and 25b are not necessarily equal.

  The display element 12a for displaying an image is not limited to the liquid crystal display shown in each embodiment, and other elements may be used. For example, a self-luminous type such as electroluminescence (EL) or a light emitting diode array can be used.

1 is a diagram illustrating an appearance of a video display device according to a first embodiment. The figure which shows the optical module of the video display apparatus of 1st Embodiment. The figure which shows the visual field of the external field observed with the video display apparatus of 1st Embodiment. The figure which shows the direction variable mechanism of the left optical module of the video display apparatus of 1st Embodiment. The figure which shows the setting method of the direction of the left optical module of the video display apparatus of 1st Embodiment. The figure which shows the direction variable mechanism of the right optical module of the video display apparatus of 1st Embodiment. The figure which shows the setting principle of the direction of the right optical module of the video display apparatus of 1st Embodiment. The figure which shows the modification of the direction variable mechanism of the right optical module of the video display apparatus of 1st Embodiment. The figure which shows the bridge periphery of the video display apparatus of 2nd Embodiment. The figure which shows the 2nd bridge | bridging of the video display apparatus of 2nd Embodiment. The figure which shows the optical module of the video display apparatus of 3rd Embodiment. The figure which shows the example of the conventional video display apparatus in which an optical axis adjustment is possible. The figure which shows another example of the conventional video display apparatus in which an optical axis adjustment is possible.

Explanation of symbols

1, 2, 3 Video display device 10, 10L, 10R Optical module 11, 11L, 11R Case 12, 12L, 12R Video display unit 12a Display element 12b Light source 12c Diffusion plate 12d Condensing lens 13, 13L, 13R Observation optical system 13a Transparent plate 13b Volume phase hologram element 14, 14L, 14R Transparent plate 15 Cable 21 Bridge 21a Recess 21b Screw receiving hole 21c Protrusion 22L, 22R Frame 23L, 23R Temple 24L, 24R Nose rest 25 Orientation mechanism 25a, 25b Inclination Plate member 26 Screw 27 Holding plate 27a Through hole 27b Protruding portion 28 Orientation changing mechanism 28a Annular member 28b Screw 28p Orientation setting surface 29 Screw 30 Second bridge 31 Screw

Claims (10)

An image display device that provides images to the left and right eyes of an observer,
The left display unit that displays the video to be provided to the left eye, the left housing that houses the left display unit, and observation of the outside world with the left eye, and the light from the left display unit is guided to the left eye A left optical module composed of a left optical system that provides a virtual image of the image displayed by the left display unit overlaid on a part of the observed outside world;
The right display unit that displays the video to be provided to the right eye, the right housing that houses the right display unit, and observation of the outside world with the right eye and the light from the right display unit are guided to the right eye A right optical module comprising a right optical system that provides a virtual image of the image displayed by the right display unit overlaid on a part of the observed outside world;
A connecting portion for connecting the left optical module and the right optical module;
An orientation variable mechanism that is provided between the left optical module and the connecting portion and between the right optical module and the connecting portion, and makes the orientation of the left optical module and the right optical module variable ,
The left optical module and the right optical module are connected, and the connection by the connecting portion is reinforced, and the connection reinforcing portion that absorbs the displacement of the left optical module and the right optical module by the direction changing mechanism is provided.
The connecting portion and the connecting reinforcing portion are positioned immediately before the left eye and the right eye when mounted on the head, and are fixed so as to sandwich the left and right optical modules from the front and rear directions,
An image display device characterized in that the direction changing mechanism defines two direction setting surfaces respectively defining directions of the left optical module and the right optical module with respect to the connecting portion, and an angle of the direction setting surface is variable . The direction changing mechanism has a first surface that is in contact with the connecting portion, and a second surface that faces the first surface and is inclined with respect to the first surface, and is rotatable along the first surface. 1 inclined plate-like member, a first surface in contact with the second surface of the first inclined plate-like member, and a second surface that faces the first surface and is inclined with respect to the first surface. and consists of the first second rotatable along the surface of the inclined plate member, to claim 1, characterized in that defining the direction setting surface with the second surface of the second inclined plate member The video display device described.   The optical module and the connecting portion are fixed by screws, and the direction changing mechanism is formed of an annular member inserted through a screw between the optical module and the connecting portion. The video display device described.   The video display device according to claim 1, wherein the direction changing mechanism includes two or three screws attached to the connecting portion so that an end portion thereof protrudes toward the optical module. . The inclination of the second surface with respect to the first surface of the first inclined plate member is equal to the inclination of the second surface with respect to the first surface of the second inclined plate member. The video display device according to claim 2 . The orientation changing mechanism changes the orientation of the left optical module in a first direction and changes the orientation of the right optical module in a second direction perpendicular to the first direction. The video display device according to claim 5 . Claim, characterized in that it comprises a transparent plate-like member that transmits light from the outside world with the left optical system and the right optical system to advance by total reflection within the light from the left display unit and a right display unit, respectively 1 video display according to any one of up to claim 6. Claim 1, characterized in that it comprises a volume phase type hologram element left optical system and the right optical system each reflected light from the left display unit and a right display unit to provide a virtual image to claim 7 2. The video display device according to item 1.   The left optical module and the right optical module are positioned immediately in front of the left eye and the right eye, respectively, when the head is mounted on the head. The video display device according to any one of claims 1 to 8. An eyeglass type in which the mounting portion includes a left temple attached to the left optical module and supported by the left head, a right temple attached to the right optical module and supported by the right head, and a nose pad supported by the nose. video display according to claim 9, wherein the der Ru.

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