KR100225560B1 - Real image finder system for a camera - Google Patents

Abstract

The actual finder system of the camera has an objective lens, an eyepiece and a deflection system. The deflection system includes a sizing system located between the objective lens and the eyepiece. The finder system also includes an LCD panel placed on the image plane of the objective lens, which displays the information observed through the eyepiece. The first polarizer is located between the objective lens and the LCD panel while the second polarizer is located between the LCD panel and the eyepiece. The first and second polarizers are arranged such that their transmission axes are perpendicular to each other. Moreover, at least one optical member of the deflection system is placed between the first polarizer and the second polarizer.

Description

Real finder system

1 shows a first embodiment of a finder optical system according to the invention,

2 shows the directions of the first and second polarizers used in the first embodiment shown in FIG.

FIG. 3 shows an example of information displayed on the LCD display panel used in the first embodiment shown in FIG.

4 shows a line diagram of light incident on the Dach mirror used in the first embodiment shown in FIG.

5 and 6 show examples of two types of materials used for the reflective elements of the front and rear optical members in the first embodiment shown in FIG.

7A and 7B show a Poincare spherical surface illustrating the displacement in polarization of the light beam when the light is reflected by the Daha mirror shown in FIG. 4,

8 shows a second embodiment of a finder optical system according to the invention.

FIG. 9 shows the directions of the first and second polarizers used in the second embodiment shown in FIG.

10 shows the phase shift of linearly deflected light after being reflected by the reflective surface of the pentagonal prism of the second embodiment shown in FIG. 8 for five different types of coatings over the wavelength range of light,

11 shows a third embodiment of a finder optical system according to the invention,

12 shows a line diagram of light incident on a pair of mirrors having an incidence plane perpendicular to each other,

13 shows a fourth embodiment of a finder optical system according to the invention,

14 shows a first arrangement of an LCD display panel, a pair of polarizers and optical elements according to the present invention,

15 shows a second arrangement of an LCD display panel, a pair of polarizers and optical elements according to the present invention,

16 shows a third arrangement of an LCD display panel, a pair of polarizers and optical elements according to the present invention,

17 shows a fifth embodiment of a finder optical system according to the present invention.

* Explanation of symbols for main parts of the drawings

10: first polarizer 21: die mirror (front optical member)

31: pentagonal prism (rear optical member) 40: second polarizer

50: LCD panel 60: objective lens

70: eyepiece

[Background of invention]

TECHNICAL FIELD The present invention relates to an optical finder system, and more particularly, to an actual optical finder system having an LCD display panel for displaying information superimposed on an image viewed in the finder.

In the optical type optical finder, the subject image is formed on the image plane by the objective lens group. This image is then observed by the user using the eyepiece group. For the information to be viewed on the LCD display, the LCD display must be placed in a plane coinciding with the image plane.

The information displayed on the LCD panel is superimposed on top of what is shown in the finder and may contain alphabetic characters. Moreover, for example, lines or symbols may be displayed that delimit the area of the image used by the distance measuring device for determining the distance of the subject from the camera. Recently, zoom compact cameras using the above-mentioned optical finder system have been introduced. In such cameras, the finder also includes a moving lens group, which is used to change the magnification of the image seen in the finder according to the focal length of the photographing lens. The information displayed on the LCD display may change as the focal length changes.

The LCD display device is composed of an LCD panel and a polarizer disposed on one side of the LCD panel and in proximity to the LCD panel. With this structure, there are six surfaces associated with the LCD display device placed very close to the image plane. During fabrication of the camera and in normal use of the camera, merge particles that may enter the finder system may be attached to the six planes. Thus, the dust particles are visible to the observer's eye, resulting in an undesirable image seen through the finder.

One way to reduce the number of surfaces near the image plane is to move the polarizer far enough out of focus from the LCD panel. However, with this structure, the size of the finder is turned on, making it difficult to reduce the size of the camera.

[Overview of invention]

Accordingly, an object of the present invention is to provide an optical finder having an LCD display device for minimizing the overall size of the finder and at the same time superimposing information on the upper part visible through the finder.

In order to achieve this object, according to the present invention, there is provided a real finder system having an objective lens, an eyepiece and a deflection system including a sizing system located between the objective lens and the eyepiece, which is placed on an image plane of the objective lens. LCD panel for displaying information to the photographer through the eyepiece: a first polarizer positioned between the objective lens and the LCD panel; and a second polarizer positioned between the LCD panel and the eyepiece, wherein the first polarizer and the first polarizer The two polarizers are arranged such that the transmission axes are perpendicular to each other: at least one optical member of the deflection system lies between the first and second polarizers.

Optionally, the deflection system may have a front optical member placed between the first polarizer and the LCD panel and a rear optical member placed between the second polarizer and the LCD panel.

Moreover, the deflection system may have only the front optical member between the polarizers or only the rear optical member between the polarizers.

At least one optical member consists of a first type of element having two reflective surfaces, each of which is defined by a plane comprising a ray along the axis of the objective lens and a normal to any of the reflective surfaces. If the planes of incidence of the reflecting surfaces are neither parallel nor perpendicular to each other, the direction of the transmission axis of one polarizer should coincide with the direction parallel to the long side of the viewfinder field, and the direction of the transmission axis of the other polarizer is parallel to the short side of the field of view of the finder. One direction light must match.

Furthermore, the first type of element may be a Daha mirror, in which the ridge line is included in a plane with an optical axis and arranged parallel to the long side of the finder field of view. This dacha mirror is arranged such that the angle between the ridge line and the optical axis is 45 degrees.

If the optical member has a second type of element with two reflective surfaces having incidence planes parallel to each other and no first type of element, the direction of the transmission axis of one polarizer is the direction of the long side of the viewfinder. Must be at an angle of 45 ° with respect to the long side of the viewfinder, and the direction of the transmission axis of the other polarizer is perpendicular to the first polarizer.

In the case where all the optical members are elements of the third type with two reflective surfaces having incidence planes perpendicular to each other, the direction of the transmission axis of the first polarizer may be any angle.

In addition, the second type of element may be a pentagonal prism and the third type of element may be a Porro prism.

[Description of Example]

Fig. 14 shows the first arrangement of the optical elements and the LCD panel of the finder optical system according to the present invention. In general, the finder is composed of an objective lens, an upright system, and an eyepiece in order with respect to a subject to be observed. In this first arrangement, the first polarizer 10 is located close to the subject side of the finder, and the front optical member 20 of the optical elements is located between the first polarizer 10 and the LCD panel 50. Next, the rear optical member 30 of the optical elements is positioned between the LCD panel 50 and the second polarizer 40. The second polarizer 40 is placed on the eye side of the finder. The LCD panel is positioned to coincide with the image plane in focus of the finder objective system (not shown). In this first arrangement, all optical elements, such as image optics, are positioned between the first polarizer 10 and the second polarizer 40. This reduces the overall length of the finder optical system when compared to a finder system in which no optical member is positioned between the first and second polarizers 10, 40. Moreover, because the optical elements are thicker than the first and second polarizers 10 and 40 (in the optical axis direction), there is less surface where dust can adhere to near the focused image plane of the objective system.

FIG. 1 shows a first embodiment of a finder optical system according to the first arrangement shown in FIG. 14. In this first embodiment, the objective lens 60 and the eyepiece 70 are provided. Lenses 60 and 70 prevent dirt and other contaminants from entering the finder system.

In this first embodiment, the front optical member 21 is a polyhedral mirror (or 'roof' mirror) with reflective surfaces 211 and 212. The rear optical member 31 is a pentaprism having reflective surfaces 311 and 312.

As shown in FIG. 1, light incident on the Daha mirror is inverted as described below, and an image is formed on the focused image plane that coincides with the image forming surface of the LCD display device 50. As shown in FIG. The light is then incident on the reflective surface 312 of the pentagonal prism and reflected on the reflective surface 311. Light is then reflected and viewed through the eyepiece 70.

Reflective surfaces 311 and 312 are arranged such that the plane of incidence on each surface 311, 312 is parallel.

In this first embodiment, the light rays incident on the Doha mirror and symmetrical with respect to the side between the reflective surface 211 and the reflective surface 212 are such that the reflected rays are symmetrical with respect to the optical axis AX. Reflected and reversed. Moreover, since the optical axis AX of the first embodiment bears a single plane and the reflected light rays are not displaced in the Z-axis direction with respect to the optical axis AX, the overall height of the finder system can also be made small.

As shown in FIG. 1, a front optical member 21 composed of a dach mirror and a rear optical member 31 composed of a pentagonal prism are provided. Since the front optical member 21 and the rear optical member 31 are placed between the polarizers 10 and 40 as described above, the overall length of the finder system can be reduced.

2 shows the arrangement of the first and second polarizers 10, 40. In FIG. 2, the first polarizer 10 and the second polarizer 40 allow linearly polarized light to pass through. Light that can pass through the first polarizer 10 has a polarization direction or transmission axis in the X-axis direction of the finder system (ie, the long side of the finder field of view). Light that can pass through the second polarizer 40 has a transmission axis in the Z-axis direction of the finder system (ie, the short side of the finder field of view). Angles (polarization angles) 0 ° and 90 ° are defined about the X axis.

3 shows an example of the display on the LCD panel 50 of the finder system embodying the present invention. The LCD panel 50 is a twisted nematic type LCD panel. In order to make a clear display using this type of LCD panel, the first polarizer 10 and the second polarizer 40 are disposed on both sides of the LCD panel 50.

Light incident on the LCD panel 50 is first polarized by the first polarizer. When the segment of the LCD display is turned off (hereinafter referred to as off-segment), the phase of the polarized light changes by 90 °, and then the second polarized light has a phase different from that of the first polarizer by 90 °. Is transmitted through the polarizer 40. When the segment of the LCD panel 50 is turned on (hereinafter referred to as on-segment), the polarization of light is not affected. However, light cannot pass through the second polarizer 40, so black segments appear on the display. Moreover, the polarization of the light also changes by 90 ° in the portion where no segment appears, which is then transmitted through the second polarizer 40.

In the example of the display device shown in FIG. 3, the panorama mode is selected.

In panoramic mode, the light blocker covers the shooting gap and draws so that the beating film is not exposed. In the finder system of the present invention, when the panorama mode is used, the finder portion becomes opaque to show the photographer the frame area to be recorded on the film. In this finder the segments 54A and 54B of the LCD panel 50 are turned ON. Make the finder part opaque and change the size of the frame area visible to the photographer.

3 also shows focal region indicator brackets 51A, 51B, 52A, 52B, 53A and 53B. When the LCD segment corresponding to each bracket becomes ON, the finder display portion becomes opaque, and the bracket is shown by the photographer. The pair of brackets displayed in the finder depends on the focal length of the zoom lens used in the camera. When the focal length is relatively short (i.e. when the zoom lens is in the wide angle setting), the brackets 51A and 51B are displayed. When the focal length is in the middle region (i.e., when the zoom lens is in the middle angle setting), brackets 52A and 52B are displayed. When the focal length is relatively long (i.e. when the zoom lens is in the telephoto setting), the brackets 53A and 53B are displayed. Moreover, only one pair of brackets is always displayed at a time, as shown by brackets 53A and 53B in FIG.

The above description of the operation of the LCD panel 50 represents an ideal situation where the incident light is fully polarized. However, if the polarized incident light is reflected by the reflective surface causing the phase shift, the reflected light will have a slightly different state of polarization from the incident light. If the reflected light is transmitted through the off-segment of the LCD panel 50, the phase shifted polarized light having no polarization corresponding to the polarization of the second polarizer 40 is passed through the second polarizer 40. Will not permeate. This reduction in light transmitted through the off-segment will result in contrasting differences between the off-segment and the portion of the LCD panel 50 that has no segment. Depending on the nature of the reflective surface, this contrasting change may be noticeable to the user, resulting in an off-segment visible. It may be cumbersome for the user to see the off-segment, so that the off-segment is visible should be minimized.

4 shows a Daha mirror used in the first embodiment shown in FIG. As shown in FIG. 4, the IR represents light rays incident on the ridge or axis A of the Doha mirror. RR represents a light beam reflected from the ridge A of the Doha mirror. PN1 and PN2 represent the normals to the surfaces 211 and 212 at the point where the ray IR is incident on the ridge A of the Doha mirror.

The plane of incidence of the reflective surface 211 is defined as a plane bearing the incident light IR and the normal PN1. Similarly, the plane of incidence of the reflective surface 212 is defined as the plane bearing the incident light IR and the normal PN2.

The dacha mirror reflects half of the incident light IR by the upper surface 212 and then by the lower surface 211, while the other half of the incident light IR is reflected by the lower surface 211. And then reflected by the upper surface 212. This creates an inverted and reversed image. Moreover, the ridge A of the Daha mirror belongs to the same XY plane as the optical axis AX, and the angle between the ridge A and the optical axis AX is 45 degrees.

The reflective surfaces 211 and 212 of the dacha mirror are perpendicular to each other. Moreover, the Daha mirror is classified as a first type of element in which the planes of incidence of the reflective surface are neither parallel nor perpendicular to each other. Therefore, the polarized light incident on the dacha mirror will have a phase shift in its S and P components. To reduce this effect, the transmission axis of polarized light incident on the Doha mirror should be parallel (or perpendicular, described below) to the plane bearing the ridge A of the Doha mirror (ie, the first and second polarizers). 10 and 40 should have a direction as shown in FIG. 2). These results have been determined experimentally by the inventors and are described in more detail below.

5 and 6 show two types of reflective elements used in optical systems. One type of reflective element (shown in FIG. 5) uses a plastic base with an aluminum layer formed thereon. A coating is applied to the aluminum layer to increase the reflectivity of the aluminum. In general, the reflectivity of aluminum can increase from 85% to about 95% depending on the coating applied.

Another reflective element (shown in FIG. 6) uses a glass base with a coating applied thereon. An aluminum layer is applied to the coating. The coating is again used to enhance the reflectivity of the aluminum layer.

In the reflective element of FIG. 5, light transmitted through the surrounding medium (ie air) passes through the coating and then enters onto the aluminum layer. The light is then reflected by the aluminum layer and passes through the coating into the air. In the reflective element of FIG. 6, light is transmitted through the glass and then passed through the coating and incident on the aluminum layer. The light is then reflected by the aluminum layer and passes through the coating into the glass.

Five different combinations of coatings applied to the aluminum layer were tested to determine which combination of coatings maximizes the reflectivity of the Doha mirror. Five different coating combinations are summarized in Table 1. The term 'nd' refers to the product of the reflection index 'n' and the thickness 'd' of the coating measured in μm. Doing so, the coatings are listed in the order in which they were applied on the base aluminum layer. For example, the coating combination example 1 has a further SiO ₂ layer (nd = 177.00) is applied on top of the SiO ₂ layer (nd = 74.75) and the SiO ₂ layer TiO ₂ layer is applied to the upper, and TiO ₂ on the aluminum base layer have.

TABLE 1

However, when another coating was applied to the aluminum layer, another effect was observed on the polarization of the incident light. Moreover, the effect on the polarized light was dependent on the angle of the transmission axis of the polarized light with respect to the ridge line of the Daha mirror. For 0 ° linearly polarized incident light (ie, light having a polarization axis parallel to the plane bearing the ridge of the Daha mirror), the Daha mirror had little effect on the surface light of the light. However, the effect on the polarization of the incident light that is linearly polarized at 45 ° was very large.

7A and 7B show the Poincaré spherical surface used to account for the change in polarization of the light reflected by the Daha mirror. As shown in Fig. 7a, the equator circumference of the Poincaré sphere shows linear polarization, while the pole shows circular polarization. The remaining area shows the elliptical polarization between the linear and circular polarizations.

Point PO represents incident light linearly polarized at 0 ° while point P45 represents incident light having 45 ° linearly polarized light.

The direction of the axis of rotation AX1 of the equator plane bearing PO and P45 is determined based on the azimuth angle of the first reflective surface 211 of the Doha mirror 21 with respect to the incident light beam. Next, when reflected by the first reflection plane 211 about the equator plane AX1, the light is rotated by an angle equal to the phase shift in polarized light. Therefore, point PO is moved to point PO 'and point P45 is moved to point P45'.

In order to observe the effect of reflection by the second reflecting surface 212, the dacha mirror 21 rotates the plane bearing PO 'and P45' by an angle equal to the phase shift of the polarization of the light about the axis AX2. do. This results in the point PO 'moving to PO and the point P45' moving to P45 as shown in FIG. 7B.

Thus, as shown in Fig. 7B, the point PO is almost close to the original point PO, so that the overall effect of the dacha mirror on the polarization of the incident light linearly polarized by 0 ° becomes small. However, the point P45 is farther away from the point P45, so that the effect on the polarization of the 45 ° linearly polarized incident light becomes large.

Moreover, the effect on 90 ° linearly polarized incident light is similar to that of 0 ° linearly polarized incident light, as can be seen by the Poincaré spherical symmetry. In addition, the effect on incident light that is linearly polarized at -45 ° is also similar to that of incident light that is linearly polarized on + 45 °.

In the above description, light was reflected by the first surface 211 of the Doha mirror and then by the second surface 212. However, the order of reflections may be reversed, which results in similar effects observed.

15 shows a second arrangement of the optical elements and the LCD panel 50 according to the invention. In this second array, the first polarizer 10 is located close to the subject side of the finder. Next, the LCD panel 50 is positioned between the first polarizer 10 and the rear optical member 30 which is an optical element. The second polarizer 40 is placed behind the rear optical member 30 at the eye side of the finder. In this second arrangement, some optical elements such as image optics are positioned between the LCD panel 50 and the second polarizer 40 so that the overall length of the finder is no optical element. It can be reduced in comparison with a finder that is not located between and the second polarizer 40. Furthermore, because the optical elements are thicker than the polarizers 10, 40 (in the optical axis direction), there is a surface where dust may adhere to the near-focused image plane of the LCD panel 50 as described above in the first arrangement. Less

8 shows a second embodiment according to the present invention. The optical elements of the second embodiment are arranged according to the second arrangement shown in FIG. Moreover, the Daha mirror 21 and the pentagonal prism 31 used in the first embodiment are also used in the second salsi embodiment. However, the dacha mirror 21 is positioned between the first polarizer 10 and the objective lens 60.

In this second embodiment, since the Doha mirror is used as the upright system, the overall height of the finder system can be reduced as described above for the first embodiment. Moreover, since the rear optical member 31 is located between the LCD 50 and the second polarizer 40, the overall length of the finder system can be reduced.

In addition, in this second embodiment, since the Doha mirror is not between the first and second polarizers 10 and 40, the phase shift of the polarization induced by the Doha mirror does not affect the image seen in the finder optical system. Moreover, a pentagram prism is a second type of element in which the planes of incidence of the reflective surface are parallel to each other and parallel to either side of the view of the finder.

Therefore, the transmission axis of the polarizers 10 and 40 can be as shown in FIG. 9 as well as in FIG. In this way, the first polarizer 10 can be made in a direction that allows 45 ° linearly polarized light to pass therethrough. Similarly, the second polarizer 40 must be directed at a phase that is different from the first polarizer 10 by 90 ° in order to allow the -45 ° linearly polarized light to pass therethrough. In this direction, the first polarizer 10 is a mirror image of the second polarizer 40, so that the polarization effect of the second polarizer 40 can be obtained by turning the first polarizer 10 forward. have. Therefore, only one type of polarizer needs to be manufactured during the manufacture of the finder optical system according to this second embodiment, so that the number of parts in the camera is reduced.

However, using this second embodiment with polarizers 10 and 40 arranged in accordance with FIG. 9, the light incident on the pentagonal prism 31 is linearly polarized by 45 ° and the reflective surface of the pentagonal prism. 311 and 312 will result in some phase shift into the polarization of the incident light as described below.

The reflective surfaces 311 and 312 of the pentagonal prism are similar to the reflective elements shown in FIG. 6, where a coating is applied to the surface of the glass base and an aluminum layer is formed over the coating. Five different combinations of coatings applied between the aluminum layer and the glass base were tested for the effect on the phase of linearly polarized light reflected by the reflective surface of the pentagonal prism. Five different combinations are summarized in Table 2.

TABLE 2

FIG. 10 shows the phase shift of polarized light after being reflected by one of the reflective surfaces of the pentagonal prism with respect to the wavelength of the polarized light (for light having a wavelength from 400 nm to 700 nm). Letters B, G and R indicate the color of the light (ie, blue, green and red, respectively). The five plots shown correspond to the coating combinations of Examples 6-10 shown in Table 2.

As shown in FIG. 10, when the pentagonal prism has the coating of Example 7 applied between glass and aluminum, the phase shift of polarized light has a minimum change over the range of wavelengths shown. Moreover, such coatings produce negligible phase shifts, making them the most suitable coatings for reflective surfaces of pentagonal prisms to prevent phase shifts in polarized light reflected along the reflective surface.

11 shows a third embodiment according to the invention. The optical elements of this third embodiment are also arranged according to the second arrangement shown in FIG. Moreover, the rear optical member 32, which is a Porro prism, establishes the image of the subject. The captive prisms are optically equivalent to the combination of prisms having reflective surfaces 401 and 402 shown in FIG. By the use of captive prisms. Only one phase standing optical element is needed in this third embodiment. Furthermore, since the captive prism is located between the LCD panel 50 and the second polarizer 40, the overall length of the finder system can be reduced.

FIG. 12 shows prisms arranged such that the plane of incidence on reflective surface 401 is perpendicular to the plane of incidence on reflective surface 402. As shown in FIG. 12, the entire incident light is reflected by the reflecting surface 401 toward the reflecting surface 402, and then by the reflecting surface 402 as the emitting line.

Since poroprism is a third type of element in which the planes of incidence are perpendicular to each other, any phase shift caused by polarization of light by either of the reflective surfaces is caused by the other reflective surface when the phase changes of both surfaces are equal. Canceled by phase shift. With this structure, the polarization of incident light is not limited to 0 ° but can also be + 45 °. Therefore, any arrangement of the first and second polarizers 10 and 40 shown in FIGS. 2 and 9 can be used. Moreover, the transmission axis of the first polarizer 10 is not limited to 0 ° or 45 °, and any transmission axis can be used. The second polarizer 40 should then be arranged to have polarization with a 90 ° phase difference from the first polarizer 10. In addition, the type of coating applied to the reflective surface produces no additional effect on the polarization of light.

13 shows a fourth embodiment according to the present invention. The optical elements of this fourth embodiment are arranged in accordance with the first arrangement shown in FIG. The combination of the front optical member 23 and the rear optical member 33 is optically equivalent to the porprism shown in the rear optical member 32 of the third embodiment. Moreover, both the front optical member 23 and the rear optical member 33 are elements of the third type. Therefore, the polarization of the incident light as described above will be 0 ° or + 45 °. However, by using the front optical member 23 and the rear optical member 33, the number of surfaces close to the focused image plane can be reduced. This reduces the number of surfaces to which dust can adhere. Furthermore, by positioning the front optical member 23 and the rear optical member 33 between the polarizers 10 and 40, the length of the finder optical system can be reduced.

16 shows a third arrangement of the optical elements and LCD panel according to the invention. In this third arrangement, the first polarizer 10 is located close to the subject side of the finder. Among the optical elements, the front optical member 20 is positioned between the first polarizer 10 and the LCD panel 50. The second polarizer 40 is placed behind the LCD panel 50 on the eye side of the finder.

In this third array, some optical elements, such as phase-mounted optics, are positioned between the first and second polarizers 10 and 40, respectively. This reduces the overall length of the finder optics system. Furthermore, since the optical elements are thicker than the polarizers 10 and 40 (in the optical axis direction), there is a surface where dust may adhere to near the focused image plane of the LCD panel 50 as described above in the first arrangement. Less

17 shows a fifth embodiment according to the present invention. This fifth embodiment has a third arrangement of the optical members shown in FIG.

As shown in FIG. 17, the front optical member is composed of the Doha mirror 21 and the condenser lens 5. As shown in FIG. The objective lens group 60A is composed of two lenses 61 and 62. The first polarizer 10 is located between the objective lens group 60A and the dacha mirror 21. The transmission axis of the first polarizer 10 is parallel to the plane bearing the ridge of the dacha mirror as shown in FIG. The LCD panel 50 is positioned between the second polarizer 40 and the condenser lens 25.

The transmission axis of the second polarizer 40 is perpendicular to the transmission axis of the first polarizer, as shown in FIG. The pentagonal prism 31 is positioned between the second polarizer 40 and the eyepiece 70. The first polarizer 10 seals the casing 11 together with the glass panel 71 so that the casing 11 has airtightness.

With this structure, some optical members used in the finder system are positioned between the first polarizer 10 and the LCD panel 50. Thus, the number of surfaces near the focused image plane is reduced. Moreover, the length of the finder system can be reduced by placing such optical members between the first polarizer 10 and the LCD panel 50.

Further, in the embodiment of the present invention, a TN type liquid crystal panel is used as the LCD panel 50, the transmission axes of which are perpendicular to each other, the ON segment becomes opaque and the OFF segment becomes transparent. On the contrary, the transmission axis may be parallel to each other. In this case, the ON segment becomes transparent and the OFF segment becomes opaque. As such, the present invention can be applied regardless of the ON / OFF logic.

The drawings and the specification disclose preferred embodiments of the invention, although certain terms are used. It is for general description only and is not intended to be limiting.

Claims (29)

A real finder system having a deflection system comprising an objective lens, an eyepiece and a sizing system positioned between the objective lens and the eyepiece, the finder system being placed on an image plane of a four-eye objective lens and A single LCD panel for displaying the information shown through: a first polarizer positioned between the objective lens and the single LCD panel: and a second polarizer positioned between the single LCD panel and the eyepiece, the deflection At least one optical member of the system is positioned between the first polarizer and the second polarizer. The image forming apparatus of claim 1, wherein the at least one optical member comprises a front optical member disposed between the first polarizer and the LCD panel, and a rear optical member disposed between the second polarizer and the LCD panel. Finder system. The finder of claim 1, wherein the at least one optical member comprises a front optical member disposed between the first polarizer and the LCD panel, and the LCD panel faces the second polarizer directly. system. The finder of claim 1, wherein the at least one optical member comprises a rear optical member disposed between the second polarizer and the LCD panel, wherein the LCD panel faces the first polarizer directly. system. The optical element of claim 2, wherein any one of the optical members includes a first type of element having two reflective surfaces, each incidence plane being along the optical axis of the objective lens, and the normal to any of the reflective surfaces. The incidence planes of the two reflective surfaces defined by the plane comprising N are neither parallel nor perpendicular to each other, and the direction of the transmission axis of any one of the polarizers coincides with the direction parallel to the long side of the finder field of view and the other transmission. The direction of the axis coincides with the direction along the short side of the viewfinder field of view. 6. The method of claim 5, wherein the first type of element is a dacha mirror that is included in a plane bearing the optical axis and has a ridge line parallel to the long axis of the finder field of view, wherein the dachmirror is between the ridge line and the optical axis. An actual finder system, wherein the angle is arranged to be 45 degrees. 6. The finder system of claim 5 wherein any one of said optical members comprises a second type of element having two reflective surfaces, said incidence planes of said reflective surface being parallel to each other. 8. The finder system of claim 7, wherein the second type of element is a pentaprism arranged on an opposite side of the LCD panel from the first type of element. 3. The optical element of claim 2, wherein the optical member comprises a second type of element having two reflective surfaces, each incidence plane comprising a ray along the optical axis of the objective lens and a normal to either of the reflective surfaces. The planes of incidence of the two reflective surfaces defined as planes are parallel to each other, and the direction of the transmission axis of one of the polarizers coincides with the direction parallel to the long side of the view of the finder and the direction of the other transmission axis is the view of the finder field of view. The finder system, characterized in that it corresponds to the direction along the short side of the. 10. The finder system of claim 9 wherein the second type of element is a pentagonal prism. 3. The optical element of claim 2, wherein the optical member comprises a second type of element having two reflective surfaces, each incidence plane comprising a ray along the optical axis of the objective lens and a normal to either of the reflective surfaces. The finder is characterized in that the incidence planes of the two reflective surfaces defined as planes are parallel to each other, and the transmission axis of the polarizer is +45 degrees and -45 degrees with respect to the direction parallel to the long side of the viewfinder. system. 12. The finder system of claim 11 wherein the second type of element is a pentagonal prism. 3. The optical element of claim 2, wherein the optical member comprises a third type of element having two reflective surfaces, each incidence plane comprising a ray along the optical axis of the objective lens and a normal to either of the reflective surfaces. 2. The finder system of claim 2, wherein the incidence planes of the two reflective surfaces defined as planes are perpendicular to each other. 15. The finder system of claim 13 wherein the third type of element is a pentagonal prism. 3. The method of claim 2, wherein the front optical member comprises a first type of element having two reflective surfaces, each incidence plane defining a normal to any one of the reflective surface and the ray along the optical axis of the objective lens. The incidence planes of the two reflective surfaces defined by the containing plane are neither parallel nor perpendicular to each other, and the rear optical member has a second type of element with two reflective surfaces having incidence planes parallel to each other, and And the direction of the transmission axis of one of the polarizers coincides with the direction parallel to the long side of the viewfinder and the direction of the other transmission axis coincides with the direction along the short side of the finder field of view. 3. The light emitting apparatus according to claim 2, wherein the front optical member and the rear optical member are each composed of a third type of element having two reflective surfaces, each incidence plane of which the ray of light along the optical axis of the objective lens and the reflective surface 2. The finder system of claim 2, wherein the incidence planes of the two reflective surfaces defined by the plane including the normal to one are perpendicular to each other. 2. A light source according to claim 1, wherein said at least one optical member comprises a third type of element having two reflective surfaces, each incidence plane being directed to any one of said reflective surface and the ray along the optical axis of said objective lens. The incidence planes of the two reflective surfaces defined by the plane including the normal are neither parallel nor perpendicular to each other, and the direction of transmission of either polarizer coincides with the direction parallel to the elongated plane of the finder field of view and the other The direction of the transmission axis coincides with the direction along the short side of the viewfinder field of view. 18. The finder system of claim 17, wherein the at least one optical member further comprises a second type of element having two reflective surfaces having incident planes parallel to one another. 19. The device of claim 18, wherein the first type of element is a dach mirror placed between the LCD panel and the first polarizer, and the second type of element is an pentagonal prism placed between the LCD panel and the second polarizer. Actual finder system characterized by. The optical device of claim 1, wherein the at least one optical member has a second type of element having two reflective surfaces, each incidence plane being directed to any one of the reflective surface and the ray along the optical axis of the objective lens. 2. The finder system of claim 2, wherein the incidence planes of the two reflective surfaces defined as planes including normals are parallel to each other. 21. The actual finder system according to claim 20, wherein the transmission axes of the first and second polarizers are +45 degrees and -45 degrees with respect to the direction parallel to the long side of the pannider view. 21. The method of claim 20, wherein the direction of the transmission axis of any one of the polarizers coincides with a direction parallel to the long side of the viewfinder and the direction of the other transmission axis coincides with the direction along the short side of the viewfinder. Actually finder system. 21. The device of claim 20, wherein a first type of element having two reflective surfaces lies between the objective lens and the first polarizer, each incident plane having a light ray along the optical axis of the objective lens and the reflective surface. 2. The finder system of claim 2, wherein the planes of incidence of the two reflective surfaces defined by the plane including the normal to one are neither parallel nor perpendicular to each other. The optical system of claim 1, wherein the at least one optical member includes a third type of element having two reflective surfaces, each incidence plane being directed to any one of the reflective surface and the ray along the optical axis of the objective lens. 2. The finder system of claim 2, wherein the incidence planes of the two reflective surfaces defined as planes including normals are perpendicular to each other. 25. The finder system of claim 24 wherein the third type of element lies between the LCD panel and the second polarizer, the LCD panel facing directly to the first polarizer. 25. The device of claim 24, wherein one of the third type of elements is placed between the first polarizer and the LCD panel, and the other of the third type of elements is between the LCD panel and the second polarizer. Finder system, characterized in that placed on. The finder system of claim 1, wherein the at least one optical member is separated from the LCD panel and the first and second polarizers. 2. The finder system of claim 1 wherein the transmission axes of the first and second polarizers are arranged so as to be perpendicular to each other. 29. The finder system according to any one of claims 1 to 28, wherein said system is installed in a camera.