JP2002350776A - Direct viewing stereoscopic vision mirror - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for looking stereoimages including a regulation function adequate for reproducing rugged feel complying with reality. SOLUTION: This stereoscopic vision mirror of a four-sheet mirror type is constituted by nearly perpendicularly placing two pairs of nearly parallel arranged plane mirrors and a line-of-sight regulator for changing an arranging position or arranging angle is included in at least one sheet among these plane mirrors.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a stereoscopic endoscope capable of easily stereoscopically observing a pair of stereoscopic images by looking at the stereoscopic images. The present invention relates to a stereoscopic endoscope having a function of recognizing, correcting, or changing a numerical value of a difference from unevenness in a space as a space distortion rate.

[0002]

2. Description of the Related Art There is a stereo image. This is a set of two images (usually a photograph) of the same size taken from a position shifted to the left and right, and by stereoscopically viewing this with the naked eye or through an instrument, a two-dimensional image is obtained. They can be observed as if they were three-dimensional. The origin is old,
Recognizing a space different from reality when artificially projecting different images on the left and right retinas (called an illusion) has been known for a long time. For example, 1838
At the Royal Society of Science in London, two images were displayed in a row and demonstrated binocular parallax and demonstrated stereoscopic vision (a narrow angle of 90 °).
Observation by the double mirror method). However, regarding the mechanism of stereoscopic vision, especially the mechanism by which the eye recognizes information from the outside world and converts it into stereoscopic perception, optical interpretation alone is not sufficient. It is an area that involves the perceptual function, the experience of the physical phenomena of the external world itself and its accumulation, and so on, and thus still contains unknown elements.

[0003] In stereoscopic viewing with naked eyes, the arrangement of a stereo image is reversed between the parallel vision method and the cross vision method. In any case, a special procedure is required for stereoscopic vision. In the case of parallel vision, the left eye must look at the left image and the right eye must look at the right image, and the line of sight must look far away from the left and right images. In this case, the left eye looks at the right image while the right eye looks at the left image, and throws the gaze near so that the left and right images are superimposed on one another. There are many people who cannot do it, and even a used person cannot keep their eyes close so that two images overlap, so that long-time stereoscopic vision is impossible. The difficulty is that, for example, a barrier (called a “compound eye barrier” for parallel vision or a “monocular barrier” for cross vision) between the eye and the image , But this does not go beyond the "slight" range.

[0004] There is also a method using an instrument instead of autostereoscopic vision. Representative examples include a method using a reflecting mirror, a method using a prism, and a method using an eyepiece. Among them, the method using a reflecting mirror is much closer to autostereoscopic vision than the other two methods of viewing transmitted and refracted light. Further, a stereoscopic method using a reflecting mirror includes a method different from the single mirror method, the double mirror method, and the four mirror method. The four-mirror method is a method of performing stereoscopic viewing using a total of four mirrors including a pair of objective mirrors and a pair of eyepieces, and has an advantage that an image can be observed as a normal image.

For example, when stereoscopically viewing an aerial photograph used for photogrammetry by an aircraft, a device called a “reflective stereoscopic mirror” is used, and this device is an example in which exactly four reflective mirrors are used. It can be said that there is. The aerial photograph itself in the aerial photogrammetry is a photograph taken in a vertical direction (within a deviation of 2 to 3 °), the scale magnification is limited to four standards, and a reflection type stereoscopic mirror used for stereoscopic vision is used. The magnification is fixed at 4 times.

[0006]

When a set of photographs taken by an aircraft at two photographing points separated by a predetermined distance are arranged side by side and stereoscopically viewed with this reflective stereoscopic mirror, the sense of height is exaggerated by the naked eye. Will be. This means that it is easy to determine the height, and thus one of the objectives of stereoscopic vision is met. This exaggerated height is called "exaggerated feeling." However, since the actual unevenness is distorted due to the feeling of being too high and stereoscopically viewed, it is extremely unnatural when this device is used for purposes other than the height determination. For example, it is impossible to stereoscopically view the terrain as viewed from above (without feeling excessive). Further, the feeling of excessiveness itself is not practically used with numerical values. Focusing on this point, the inventor looks at several stereoscopic images from the stored stereo images and tries to determine the degree of height exaggeration of the emerging stereo images (this is called “space distortion rate”). saw. Then, the sense of unevenness that can be obtained by stereoscopically viewing a stereo image is often different from the actual unevenness, and the stereoscopic vision itself can be changed from the photograph, even though it is within a certain range, even if the distance is changed I noticed that the unevenness was different depending on the distance. However, we do not know at all what conditions can be used for stereoscopic viewing without spatial distortion, and we must find an appropriate positional relationship by changing the distance between photos and the distance from the photos. Was. That is, at present, there is no clue to know the stereoscopic viewing condition that can reproduce the sense of real unevenness.

[0007]

In view of these points, the present inventor has finally made the present invention as a result of earnest research, and the feature of the present invention is that two pairs of the two pairs are arranged substantially in parallel. This is a four-mirror stereoscopic endoscope in which plane mirrors are formed at substantially right angles, and at least one of these plane mirrors is provided.
The point is that the sheet is provided with a line-of-sight adjusting device for changing the position or the reflection angle in the horizontal direction (the direction connecting the optical centers of the lenses of both eyes). It should be noted that the stereoscopic endoscope of the present invention is different from the conventional stereoscopic endoscope (for example, the above-mentioned reflective stereoscopic mirror) in that the mutual positional relationship of the four mirrors can be changed. This is because the left and right images can be superimposed regardless of how far apart a pair of stereo images and the like (images already taken under certain conditions) are arranged and how far they are viewed from the images. It is made possible. It is an essential function to achieve the objective of enabling stereoscopic viewing even if the distance between the image etc. and the eye is not fixed as in the past, such a change in distance is the only way to change the distance without distortion It enables visual observation. In this regard, it can be easily adjusted by the formula described later, but in short, it is not too much to say that until now there was a device that can only view stereo images and stereoscopically view it. The present invention has been completed with concern that no consideration has been made.

In order to derive the spatial distortion rate, the present inventor first assumed that the brain has the following functions. (1) Recognizing the deviation of a detected image as parallax from two different pieces of image information reflected on the retinas of the left and right eyes, constructing a virtual space from these information, and recognizing it as a real space. Then, in order to reflect this parallax information without contradiction when constructing the virtual space, the virtual space becomes three-dimensional. (2) A function to calculate the amount (value) of parallax to the distance in the gaze direction in the real space.

Further, it is assumed that the imaging position on the real space, the virtual space, and the retina can now be represented by the same coordinate system of a three-dimensional orthogonal system. The origin of this coordinate system is the optical center of the lens of one of the eyes, the Z axis is its optical axis (the direction of the line of sight), X
The axis is a straight line passing through the optical center of each lens of both eyes. The correspondence between the point P (X, Y, Z) in the real space and the point P ′ (X ′, Y ′, Z ′) in the virtual space is represented by coordinates p inside the retina.
When (x, y, z) is associated with parallax, the following relationship is obtained. P (X, Y, Z) = (1 / dx) × P (x, y, f) = P ′ (X ′, Y ′, Z ′) where f is a lens Is the parallax in the X-axis direction on the retinal plane.

With the above in mind, the change in the distance between the two points at which the image was captured, the change in the viewing distance for stereoscopically viewing the captured image, and the effect on the distortion of the virtual space in the Z-axis direction are taken into account. Then, the space distortion rate γ (where the distortion rate of the real space is set to 1) is derived as follows. γ = (D / L ′) · (B / b) (Equation 2) where D is the visual distance, L ′ is the apparent objective distance converted from the magnification of the image and the like, and B is the two The distance between the two points where the image was captured, and b is the distance between the pupils (pupils) of the person performing stereoscopic vision.

Since the present invention is a four-mirror type stereoscopic endoscope,
If at least one (preferably a pair) of the four mirrors is made rotatable, images captured by both eyes can be easily matched even if the viewing distance is changed.

The image using the stereoscopic endoscope according to the present invention is not necessarily a still image.
For example, images taken from two viewpoints by a video camera and projected on the left and right monitors can be viewed stereoscopically by viewing the images with the stereoscopic scope of the present invention.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the drawings.

FIGS. 1A and 1B show an example of a direct-view stereoscopic endoscope 1 according to the present invention (hereinafter, referred to as a stereoscopic endoscope 1 of the present invention). FIG. 1A is a perspective view and FIG. FIG. 2B is a schematic sectional view. As is clear from the drawing, the stereoscopic endoscope 1 of the present invention of this example is basically a four-mirror type stereoscopic endoscope.
Structurally, the two viewing mirrors are arranged in a straight line in the horizontal direction (the direction connecting the optical centers of the lenses of both eyes). That is, two sets in which the eyepiece 2 and the objective mirror 3 face each other in a substantially parallel positional relationship are arranged such that their parallel surfaces are substantially orthogonal to each other. Although there are two viewing holes 4 and the center-to-center distance is fixed at 6.5 cm in this example, an adjusting function may be added to cope with individual differences (not shown). The stereoscopic endoscope 1 of the present embodiment of the present embodiment is provided with two adjustment knobs. One is the objective adjustment knob 5,
The other is a line-of-sight direction adjustment knob 6.

The objective mirror adjustment knob 5 changes the distance between the two objective mirrors 3 (the eyepiece 2 does not cooperate) by rotating the knob, and in this embodiment is constituted by a rack and a pinion. ing. A scale (not shown) is printed on the housing material covering each objective mirror 3 so that the changed distance can be visually recognized as a numerical value.

The line-of-sight direction adjustment knob 6 is a member for rotating the eyepiece 2 about a vertical line. This adjustment is performed by a person who stereoscopically views the stereoscopic endoscope 1 so that the images of the left and right eyes coincide with each other. In this case, the rotation angle of the eyepiece 2 is usually several degrees to several tens degrees.
The range of rotation of the line-of-sight direction adjustment knob 6 is 4
5 ° is sufficient.

[0017]

As described in detail above, the direct-view stereoscopic endoscope according to the present invention is a four-mirror stereoscopic endoscope in which two pairs of plane mirrors arranged substantially in parallel are placed at substantially right angles. At least one of these plane mirrors is provided with a line-of-sight adjusting device for changing a horizontal position or a reflection angle, as described below. This is a very advanced invention having an effect.

(1) The left and right images can be matched regardless of the viewing distance or the image interval. (2) After the images are once adjusted, the stereoscopic vision can be continued and the details of the stereoscopic image can be observed without feeling tired as in the case of stereoscopic vision with naked eyes. (3) By using together with an expression for quantifying the distortion related to the depth between the real space and the virtual space, it is possible to quickly calculate the distortion ratio measurement and the conditions for stereoscopic viewing without distortion.

[Brief description of the drawings]

1 (a) and 1 (b) show an example of a direct-viewing type stereoscopic endoscope according to the present invention, wherein FIG. 1 (a) is a perspective view and FIG. 1 (b) is a schematic sectional view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Direct-viewing stereoscopic endoscope according to the present invention 2 Eyepiece 3 Objective mirror 4 Viewing hole 5 Objective mirror adjustment knob 6 Line-of-sight direction adjustment knob

Claims (1)

[Claims] 1. A four-mirror stereoscopic endoscope comprising two pairs of plane mirrors arranged substantially in parallel and arranged at substantially right angles,
At least one of these plane mirrors is provided with a line-of-sight adjusting tool for changing an arrangement position or an arrangement angle.