JPH02184838A - Stereoscopic optical device - Google Patents

Abstract

PURPOSE:To attain a stereoscopic photographing with an ordinary camera by selecting light beams of different wavelength regions from object light beams which are made incident from first and second incident windows arranged horizontally, composing the object light beams from the two incident windows to one screen, and optically operating the incident windows so that they stare at the object light in common. CONSTITUTION:Only the light beams of the different wavelength regions are selected from the object light which is made incident from the two incident windows 3 and 4 which are arranged separately on both sides, these different wavelength light beams are led to an optical system 11 so that a main object image formed by respective light beams can coincide with that formed by respective light beams on an image recording plane 14. Therefore, a camera 11 can appropriately photograph images from two channels in the right and left by different color sensitive emulsions, they are superposed on one screen, but they do not interfere each other. In other wards, an image free from the crosstalk of the left and right channels can be recorded. Thus, when this optical device is attached to an ordinary camera, the stereoscopic photographing can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a stereo optical device that is used by being attached to a camera for taking stereo photographs using an ordinary camera.

[Conventional technology]

Stereo photography using anaglyphic printing is already known. This method involves making a plate by superimposing two photographs taken from different viewpoints.

One photo uses ink that blocks the short wavelength range of visible light (hereinafter referred to as warm color ink), and the other photo uses ink that blocks the long wavelength range of visible light (hereinafter referred to as cool color ink).
This is a method of printing and reproducing a single image on white paper using During plate making, the amount of shift between the two photographs is set so that the images of the main subject are completely superimposed.

This print is viewed using glasses with two color filters. One of the color filters is a filter that transmits a long wavelength range of visible light (hereinafter referred to as a warm color filter), and the other is a filter that transmits a short wavelength range of visible light (hereinafter referred to as a cold color filter). The part where the cool color ink is on.

Since the degree of reflection of light in the long wavelength range is limited depending on the density, differences in density can be recognized when observed through a warm color filter. However, no matter what the density of the warm color ink, it is impossible to limit the degree of reflection of light in the long wavelength range, so if you observe it through a warm color filter, you will not be able to recognize the difference in density.
It is observed to be equivalent to no ink being applied. Therefore, the eye observing through the warm color filter only recognizes images printed with cool color ink, and does not recognize images printed with warm color ink. Similarly, the eye viewing through a cool color filter only perceives images printed with warm color inks and not images printed with cool color inks.

In this way, the observer can separate and observe the images of the two photographs printed one above the other, even if the two photographs were taken from different viewpoints. For example, stereoscopic observation is possible.

This anaglyphic printing stereo photo is printed with 52 photos stacked on top of each other.

Compared to the method of viewing two independent photos using Pure, there is no restriction on viewing distance and no need for a magnifying lens, and all you have to do is wear glasses with two color filters. It has the advantage of allowing stereo images to be viewed from various viewing angles and distances.

[Problem to be solved by the invention]

However, images produced by this anaglyphic method have the drawback that, when viewed without glasses having two color filters, the image becomes an unpleasant double image, and it is not possible to reproduce a color photograph. In addition, creating images using the anaglyphic method requires the use of a camera with a special structure to take two images of the subject from different viewpoints, and the process of compositing them, making it easy to create images. could not be created.

An object of the present invention is to improve the above-mentioned drawbacks of stereo photography using the anaglyphic method, and to make it possible to take inexpensive and easy-to-view stereo photographs using an ordinary camera. An object of the present invention is to provide a stereo optical device that is used by being attached to a camera.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention uses filters with different spectral transmission characteristics placed behind two incident windows spaced apart from each other in the left and right direction, so that the incident light from the subject is filtered through the left incident window, for example. The incident light from the left side is transmitted only with a predetermined wavelength or more, and the right incident light is transmitted only with a predetermined wavelength or less, and these lights with different wavelengths are guided to the camera's optical system, and the left incident light is transmitted on the camera side. The image of the subject incident through the window and the image of the subject incident through the right entrance window are formed independently on a single sheet of film, and are arranged in the left-right direction. first and second entrance windows for inputting light from a subject; selection means for selecting light in mutually different wavelength ranges from the subject light incident from the first and second entrance windows; and a synthesizing means for synthesizing the subject light from the second incident window into one screen, and a subject that is common to both the first and second incident windows. The invention is characterized in that it includes an optical actuation means that operates in a manner similar to that shown in FIG.

The optical actuation means is composed of a mirror device supported to swing and a drive device that operates the mirror device depending on the subject. It is preferable to operate it according to the distance information. Furthermore, the optical device may be provided with a subject distance detection means, and the drive device may be operated in accordance with the output signal thereof. Further, a semi-transparent mirror or a dichroic mirror can be used as a combining means for combining the subject light incident from the first and second entrance windows into one screen.

[For production]

From the subject light that enters from two incident windows spaced apart on the left and right, only light in different wavelength regions is selected so that the main subject images formed by each light coincide on the image recording surface. By guiding these different wavelengths of light to the camera's optical system, the camera can separate the images of the left and right channels using different color-sensitive emulsions, and although they are superimposed on one screen, There will be no interference. In other words, it is possible to record images without crosstalk between left and right channels.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 is a plan sectional view showing the basic configuration of a camera adapter embodying the present invention, and FIG. 2 is a front view of the same. In the figure, 1 is an adapter body, and 2 is a mounting portion that fits into a photographing lens barrel portion 12 of a known camera 11. Note that 13 indicates a photographing lens of the camera, and 14 indicates a film surface. In the adapter body 1, 3 and 4 are entrance windows arranged in the left and right direction. The incident light from the subject is guided into the adapter body 1. Ml and M2 are mirrors that guide the light incident from the entrance window 3 toward the optical axis 0 direction. )
, M3 is a mirror that guides the light incident from the entrance window 4 toward the optical axis 0 direction. M4 is a dichroic mirror placed on the optical axis, which has a selective transmission characteristic that transmits visible light with wavelengths above a predetermined wavelength and reflects visible light with wavelengths below a predetermined wavelength. A material that transmits light in the band to be sensitized and reflects light in the band to sensitize the green and blue sensitive layers of a color film, or a material that transmits light in the band to sensitize the red and green sensitive layers of a color film and is blue sensitive. A material having the property of reflecting light in the band in which the layer is sensitized is used. FIG. 3 is an example showing the characteristics of the dichroic ink mirror used in the present invention. As is clear from the figure, most of the light with wavelengths longer than the boundary wavelength passes through the dichroic mirror. Light with a wavelength shorter than the boundary wavelength does not pass through the dichroic mirror. Also, most of the light with wavelengths shorter than the boundary wavelength is reflected by the dichroic mirror. Light with wavelengths longer than the boundary wavelength is not reflected by the dichroic mirror.

Note that a dichroic mirror that reflects light with a wavelength longer than the predetermined wavelength and transmits light with a shorter wavelength than the predetermined wavelength may be used as the mirror M4.

The mirror M1 is attached to a gear 8 that rotates about an axis perpendicular to the plane of the drawing in FIG. The gear 8 is configured to rotate from the motor 5 via a gear train 6, 7, and is controlled to guide incident light from a subject in a direction along the optical axis, as will be described later. As shown in FIG. 2, the front surface of the adapter 1 is provided with entrance windows 3 and 4 as well as a light projecting aperture 9 and a light receiving aperture 10 for a known object distance measuring mechanism. Note that the structure of the attachment part 2 for attaching the adapter 1 to the lens barrel part 12 of the camera can be any arbitrary structure, such as attaching it to a filter screw, as long as the adapter optical axis O and the optical axis of the camera's photographing lens coincide at the time of attachment. means can be adopted.

FIG. 4 is a block diagram of a control circuit that rotates the mirror M1 based on distance information obtained by distance measuring a subject, and FIG. 5 is a diagram showing its operation timing. 21 in Figure 4
is a microprocessor (CPU'I); 22 is a clock oscillator, which is connected to the input capacitor 105 of the CPU 21 and supplies a synchronization signal to the CPU; Reference numeral 23 denotes a distance measuring light emitting circuit, which is connected to the output port OL of the CPU 21 and lights up the light emitting element LED facing the light projecting aperture 9 of the adapter 1 under the control of the CPU. 25 is a memory for temporarily storing distance measurement results, and output port O5 of the CPU 21
, OR, and is also connected to a distance measuring circuit 24 and a comparison circuit 26, which will be described later. 24 is a distance measuring circuit, which includes two light receiving elements SPD facing the light receiving aperture 10 of the adapter 1.
1 and SPD 2, and measures the distance to the subject by receiving the reflected light of the light projected onto the subject from the light emitting element LED,
A signal corresponding to the subject distance is output to the memory 25. 26
is a comparison circuit, a memory 25 and a decoder 2 to be described later.
7 and the output port OC1 of the CPU 21.
It is connected to the input ports IC1 to IC3 and compares the contents of the memory 25 with the decoding results of the decoder 27.

The comparison result is output to the CPU 21. 28 is mirror M1
A position detector detects the rotational angular position of the motor, and outputs the detection result to the decoder 27. 29 is a drive circuit for the motor 5 that rotates the mirror M1, and is connected to the output port OD of the CPU 21.
1. It is connected to OD2 and drives the motor 5 under the control of the CPU. 30 is a display section that shows the output data of the CPU 21.
Connected to I.

Next, its operation will be explained with reference to FIGS. 4 and 5. First, the memory 25 is reset at the rising edge of the reset signal from the output port OR of the CPU 21 (time point to). Next, the output of CPU 21
) At the rise of the signal from OL, the light emitting circuit for distance measurement 23
turns on the light emitting element LED (time tl). Distance measurement circuit 2
4 receives the reflected light from the subject and stores the distance signal in memory 2.
5, but while the light emitting element LED is emitting light, the CPU 2
A signal is output from output port O8 of No. 1 (time t2),
The distance signal at that time is stored in the memory 25.

On the other hand, the rotation angle position of the mirror M1 is detected by the position detector 28, and the position signal is encoded by the decoder 27 and then input to the comparison circuit 26. The comparison circuit 26 determines whether the output of the CPU 21 at time t3? - Compare the distance signal stored in the memory 25 with the position signal of the mirror M1 at the rising edge of the signal output from the OC. As a result, the main subject image is formed by the light incident from the entrance window 4.

If the mirror M1 has not rotated to a position where the main subject image formed by the light incident from the entrance window 3 matches on the film surface, the comparison circuit 26 outputs a signal to the input port IC2 of the CPU 21. do. Then, CPU 2
1 outputs a motor normal rotation signal to the motor drive circuit 29 from the output port OD1. As the mirror M1 continues to rotate, the comparison operation by the comparator circuit is repeated, and when the distance signal and the position signal match (time t4), the signal input to the CPU 21 IC2 turns OFF. A signal is input to the input port IC.

Accordingly, the CPU 21 turns off the signal from the output port OD, that is, outputs a motor stop signal to the motor drive circuit 29 to stop the mirror M1. At the same time, the CPU 21 outputs a display signal from the output port 01 to the display section 30, and notifies the operator that the main subject images of both the left and right channels match by displaying one light emission, displaying a warning sound, etc.

Note that the control circuit may stop operating when the main subject images of both the left and right channels match due to the above operation, but may continue operating in consideration of the movement of the subject. . In other words, the images of the main subject in both the left and right channels may always match as the main subject moves.

FIG. 5(b) is a diagram showing the operation timing when the rotation operation of the mirror M1 is continued in accordance with the movement of the main subject, and the comparison operation of the comparison circuit 26 is temporarily stopped at time t5, and The memory is reset and the mirror M
The adjustment operation of No. 1 is restarted. Note that FIG. 5(b) shows that the comparison operation of the comparison circuit 26 is performed at time t9, and as a result,
A case is shown in which the mirror M1 has rotated beyond the position where the main subject images of both the left and right channels coincide. In this case, the comparison circuit 26 outputs a signal to the input port IC3 of the CPU. Then, the CPU 21 outputs a motor reverse signal from the terminal OD3 to the motor drive circuit 29 to rotate the mirror M1 in the reverse direction. The time tlO when the distance signal and the position signal match.

When the signal input to the input port IC3 of the CPU 21 is turned OFF and the signal is input to the input port IC1, the CPU 21 turns OFF the signal from the output port OD2 to stop the mirror. Along with that,
The CPU 21 outputs a signal from the output port O1 to display on the display unit 3 that the main subject images of both the left and right channels match.
Display it at 0.

FIG. 6 shows a schematic optical system equivalent to the stereo camera configured by attaching the adapter 1 shown in FIG. 1 to the camera 11, and is designated by A and B in the figure.

C is an object whose distance from the camera is different, Ll,
L2 is a photographing lens, FLl and FL2 are filters with different wavelength selection characteristics, Fl and F2 are film surfaces, IM,
IM2 represents a subject image formed on a film surface, and the dichroic mirror used in adapter 1 is represented by two equivalent filters FL1 and FL2. 6th
Comparing the optical system shown in the figure with the optical system shown in Figure 1,
Filter FL1 of the optical system in FIG. Lens L□ and film surface F1 are mirror M1. M2. M4. Lens 13. Corresponding to the film plane 14, the filter F in FIG.
L2, lens L2, and film surface F2 are mirror M in Figure 1.
3, M4. S/Z13. Corresponds to the film surface 14.

The manner in which a stereo photograph is formed by the optical system shown in FIG. 6 will be explained below.

Now, when focusing on subject B, the filter FL1 transmits only the light having wavelengths shorter than a predetermined wavelength (for example, green and blue) from the light incident from the subjects AB and C, and the lens L1 focuses the light onto the film surface F1. An image IM1 is formed. Similarly, from the light incident from subjects A, B, and C, only light with a wavelength longer than a predetermined wavelength (for example, red) is transmitted through the filter FL2, and the lens L2 forms an image on the film surface F2 to form one image IM2. It is formed. Images IM1 and I
M2 is actually superimposed on dichroic mirror M4 and is formed on a single film surface, as shown in FIG. That is, the focused image B1. B2 are superimposed, and the image of the subject C, which is closer than the subject B, is the image C1 of the light that has passed through the filter FL1, that is, the light that has entered from the entrance window 3, and the image C1 that is the light that has passed through the filter FL2 and the light that has passed through the filter FL2. That is, an image C2 of light incident from the entrance window 4 is formed to the left. Furthermore, regarding the image of object A, which is farther away than object B, image A1 formed by light passing through filter FL1 is formed to the left, and image A2 formed by light passing through filter FL2 is formed to the right. Ru.

Next, two examples of preferred combinations of materials used for the pair of wavelength selective transmission filters FL□ and FL2 will be explained.

The first example is a filter FL□ that transmits light in a band that sensitizes the red-sensitive layer of a color film, such as A 25 and A of Kodak Ratten Filter (trade name).
24 or the like, and as the filter FL2, a filter that transmits light in the band that sensitizes the green and blue sensitive layers of the color film, for example, A 44 of the product name Kodak Ratten Filter.
A, A64, etc. are used. In a color film that has been photographed stereoscopically using a pair of wavelength-selective transmission filters in this combination, a latent image is recorded by the light beam that has passed through the FLl in the red-sensitive layer, and a latent image is recorded in the green-sensitive layer and the blue-sensitive layer.
A latent image is recorded by the light beam transmitted through L2.

In the second example, a filter that transmits light in a band that sensitizes the red and green sensitive layers of the color film, such as A12 of the Kodak Wratten filter, is used as the filter FL1, and a filter of the color film is used as the filter FL2. A filter that transmits light in a band that sensitizes the blue-sensitive layer, such as A47 manufactured by Kodak Ratten Filter, is used. In a color film that was photographed stereoscopically using a pair of wavelength-selective transmission filters in this combination, a latent image was recorded by the light beam that passed through FL1 in the red-sensitive layer and the green-sensitive layer, and a latent image was recorded by the light beam that passed through FL1 in the blue-sensitive layer. A latent image created by the light beam is recorded.

Therefore, both of the above two embodiments have two different viewpoints.
Two filters FL1. Although the pair of object scene images observed through FL2 are superimposed on one screen, they are recorded on independent media without any interference with each other. In other words, both left and right channels will be recorded without crosstalk.

Note that the wavelength selective transmission characteristics of the dichroic mirror may also be made to conform to the above filter characteristics.

The viewing glasses used when viewing stereo photos taken will be explained. FIG. 9 shows viewing glasses in which both eyes are provided with a pair of wavelength selective transmitting members G1 and G2, and the wavelength selective transmitting member G1 for the left eye can pass through the wavelength selective transmitting filter FL1. The wavelength-selective transmission member G2 for the right eye is still configured to pass through the wavelength-selective transmission filter FL2 so as to sufficiently transmit the light in the band and almost completely block the light in the band that can pass through the wavelength-selective transmission filter FL2. Wavelength selective transmission filter F that transmits enough light
The characteristics of each are set so as to almost completely block light in a band that can pass through L□. Therefore, the image that can be observed through the wavelength selective transmission member G□ indicated by diagonal lines is an image generated only by the light that has passed through the wavelength selective transmission filter FL1, that is, the image indicated by diagonal lines. In addition, the image that can be observed through the wavelength selective transmission member G2 indicated by the multi-dot coating 9 is the image that can be observed through the wavelength selective transmission filter FL.
This is an image generated only by the light that has passed through 2, that is, an image shown by multi-dot painting.

FIG. 8 is a photograph of the latent image on the film surface shown in FIG. 7 which has been developed into an erect image, and FIG. 10 shows how this is viewed through the glasses shown in FIG. 9. In the figure, the subject image A1A2 on the photograph. When an observer observes B1B2 and C1C2 with both eyes, apparent subject images are generated at the positions of points As, Bs, and Cs in space, respectively. As
appears to be set back from the plane of the photograph, and Bs appears to be on the same plane as the plane of the photograph.

Cs looks higher than the surface of the photo. In this way, the viewer can observe the photograph as a three-dimensional image according to the depth order of the field. In particular, since the main subject image has both left and right channel images overlapping, there is no image shift as shown by the object point image Bs, making it easy to appreciate.

FIG. 11 shows an example of a photograph obtained by photographing an actual scene. When this photograph is viewed through the glasses shown in Figure 9, the mechanism is the same as in Figure IO: the trees appear to be receding from the plane of the photograph, the main subject appears to be on the same plane as the plane of the photograph, and the shrubs appear to be on the same plane as the plane of the photograph. It appears to stand out from the surface of the photo. In this way, the viewer can observe the photograph as a three-dimensional image according to the depth order of the field.

Next, preferred combinations of wavelength selective transmission members G and G2 of glasses will be described for the two preferred combinations of wavelength selective transmission filters described above.

A preferred combination for the first example is a filter G1 that blocks light in a band whose transmission and non-transmission can be controlled by the color development of the blue-sensitive yellow color-forming layer and the green-sensitive magenta color-forming layer of a color photograph, ie, a red filter, for example. Product Name Kodak Ratten Filter A25, A2
6, A29, etc., and the filter G2 is a blue-green filter that blocks light in a band whose transmission or non-transmission can be controlled by the color development of the red-sensitive cyan coloring layer of a color photograph, such as A44A of the trade name Kodak Wratten Filter.
A44 or the like is used. A viewer who wears glasses that use this combination of a pair of wavelength-selective transmission members will see an image generated by the blue-sensitive yellow coloring layer and the green-sensitive magenta coloring layer with their left eye, and the red-sensitive cyan coloring layer with their right eye. Recognize each generated image.

A preferred combination for the second example is that the filter G1 is a filter that blocks light in a band whose transmission and non-transmission can be controlled by the coloring of the blue-sensitive yellow coloring layer of color photography, that is, an orange filter, such as Kodak Wratten (trade name). A filter A12, I615.416, etc. is used as the filter G2, which is a filter that blocks light in a band whose transmission and non-transmission can be controlled depending on the color development of the green-sensitive magenta coloring layer and the red-sensitive cyan coloring layer of a color photograph, that is, a blue filter. .

For example, the product name is Kodak Wratten Filter Noya 47, A4.
7B etc. is used. A viewer who wears glasses using this combination of a pair of wavelength-selective transmission members will see an image generated by the blue-sensitive yellow coloring layer with the left eye, and an image generated with the green-sensitive magenta coloring layer and the red-sensitive cyan coloring layer with the right eye. Recognize each image.

Therefore, by using either of the glasses of the above two embodiments, the viewer can record images on independent media on the color film taken using the wavelength selective transmission filter without any interference with each other. This means that each image can be observed separately. In other words, images of the left and right channels can be observed without crosstalk.

As mentioned above, the main subject, that is, the subject that is in focus, is filtered by filter FL1. The image formed by the light that has passed through each FL2, and the image of both the left and right channels of the tab, match on the film surface, so there is no color shift, and the colors are faithfully reproduced, allowing viewing without glasses. However, there is no problem in viewing it.

The optical system of the adapter shown in Figure 1 uses a total of four mirrors. Alternatively, a total reflection mirror M5 and a dichroic mirror M6 may be arranged to guide the light incident from the entrance windows 3 and 4 along the optical axis 0.

In addition, instead of the dichroic mirror shown in Figs.
The mirror may be a normal semi-transmissive mirror by inserting two filters.

The rotation of mirror M1 shown in Fig. 1 and mirror M5 shown in Fig. 12 can be linked to the movement of the photographing lens of the attached camera, or based on the distance measurement signal output from the automatic focus adjustment device on the camera side. It can also be activated.

It is also possible to start the operation of the control circuit by a release signal generated in response to a release operation of the camera to which the control circuit is attached.

Further, as shown in FIGS. 13 and 14, the entrance window 3,
4, filters FL each having different wavelength transmission characteristics;
, FL2 is installed and with it.

Mirrors M4 and M6 are configured with total reflection mirrors, and mirror M4. Positions M4' and M6' where M6 is indicated by a broken line
It may also be rotated up to . However, in this case,
In order to prevent camera shake due to the impact of mirror rotation, it is desirable to fix the camera 11 on a tripod, etc. For example, if a switch is provided on the tripod screw and the camera is not attached to the tripod, camera shake may occur. It may be possible to warn the photographer that there is a problem. Alternatively, shooting is 2
This is done by multiple exposures, and the mirror M4. M6 may be rotated manually or automatically.

Further, in the above embodiments, images were recorded on negative film, but medium film may also be used, and the present invention can also be applied to electronic still cameras.

〔Effect of the invention〕

As explained above, the optical device of the present invention is capable of taking stereo photographs by attaching it to a normal camera, and when viewing the taken photographs using viewing glasses. You can enjoy an image with a three-dimensional effect, and when you do not use viewing glasses, you can enjoy it as a normal color photograph.

[Brief explanation of the drawing]

Fig. 1 is a plan sectional view of a camera adapter embodying the present invention, Fig. 2 is a front view of the same, Fig. 3 is a spectral characteristic diagram of a dichroic mirror, Fig. 4 is a block diagram of a control circuit, and Fig. 5
Figure 6 shows the operation timing of the control circuit, Figure 6 shows the equivalent optical system of the optical device, Figure 7 shows the latent image of the field image recorded on the film surface, and Figure 8 shows the latent image of the field image recorded on the film surface. A diagram showing a field image obtained by developing the same film as above, FIG. 9 is an explanatory diagram of viewing glasses, and FIG. 10 is an explanatory diagram of the optical path when the field image shown in FIG. 8 is viewed through viewing glasses. FIG. 11 is an explanatory diagram of a photographed object scene image, and FIGS. 12, 13, and 14 are plan sectional views of other embodiments of the camera adapter. 1: Camera adapter body, 3.4: Entrance window, Ml,
M2. M3. M5: Mirror, M4. M6: Dichroic mirror, 11: Camera, 13: Photographic lens Patent applicant Minolta Camera Co., Ltd. (a) Figure (b) Figure Figure Figure Figure 1゜Figure Figure Figure Figure Figure

Claims (7)

[Claims] (1) First and second entrance windows for inputting light from objects arranged in the left and right direction, and light in different wavelength ranges from the object light entering from the first and second entrance windows. A selection means for selecting, a combining means for combining the subject light from the first and second entrance windows into one screen, and an optical operation means for operating so that the first and second entrance windows both stare at a common subject. A stereo optical device comprising: (2) In the stereo optical device according to claim 1,
The optical actuation means includes a swingably supported mirror device;
A stereo optical device comprising: a drive device that operates the mirror device according to a subject. (3) In the stereo optical device according to claim 2,
A stereo optical device characterized in that a driving device is linked to the extension of a camera lens. (4) In the stereo optical device according to claim 2,
A stereo optical device characterized in that a driving device operates according to object distance information of a camera. (5) In the stereo optical device according to claim 2,
A stereo optical device further comprising a detection means for detecting a subject distance, and a driving means operated in response to a signal from the detection means. (6) In the stereo optical device according to claim 1,
A stereo optical device characterized in that the combining means is a semi-transparent mirror. (7) In the stereo optical device according to claim 6,
A stereo optical device characterized in that the selection means and the semi-transparent mirror are the same dichroic mirror.