KR20000007285A - Stereo camera - Google Patents

Abstract

PURPOSE: A stereo camera is provided to easily take a stereo picture exerting the best stereo effect by setting a linear or a circular arc trace to a using purpose of the stereo camera or a using method of a photographing camera. CONSTITUTION: A left lens board(42L) and a right lens board(42R) of a stereo camera(41) are coupled to a camera main body(46) through upper/lower two sets of parallel link(47). Parallel grooves(45L, 45R) of a horizontal direction are formed on an internal side of the lens boards(42L, 42R) to be coupled to a circular eccentricity cam(43). If an axis attaching the cam(43) is revolved, parallel translation of the lens boards(42L, 42R) is performed to control a focus and a light axis spacing.

Description

Stereo camera

The present invention relates to a stereo camera, and more particularly, to a stereo camera in which the distance between optical axes of two photographing lenses is adjusted in conjunction with focus adjustment.

In a stereo camera which takes two sets of photographs by a pair of left and right photographing lenses, it is common that the distance between the optical axes of the two photographing lenses is fixed. Such an optical axis distance fixed stereo camera has an overlapping area between the left and right photographing images L and R due to the parallax of two photographing lenses, as shown in FIGS. 20L and 20R. Non-redundant regions a to b and c to d are generated outside of b to C, respectively. Further, as the subject distance gets closer, the position of the subject image on the left and right photographing images shifts in the approach direction.

The non-overlapping areas a to b and c to d are portions in which a stereoscopic image is not formed. When viewing with a stereo slide viewer, as shown in FIG. 21, the screen frame of the slide mount is located at the boundary of the non-redundant area. Overlapping is annoying. In addition, there is an unnaturalness in which the three-dimensional image of the subject nearer than the focal length is seen in front of the stereo window (the virtual window in which the left and right picture frames of the mount coincide when the stereo slide is stereoscopically viewed as one). It is often seen with stereo slides.

Therefore, in order to correct these drawbacks, the non-redundant areas a to b and c to d of the left and right screens are masked by a stereo slide mount having a narrower window width than the screen width of the film, and the pitch of the left and right films is fixed. Adjusting to correct the perspective is performed. However, the above method is not only easy to determine the appropriate mask amount or the transverse position of the film with respect to the window of the mount, but also has the problem that the loss of the screen due to the execution of the mask is large.

The above problems caused by the clock difference between the left and right photographing lenses can be solved by adjusting the distance between the optical axes of the left and right photographing lenses to correct the clock. It is known that the manual control type that can adjust the distance between the optical axis irrespective of the other, the automatic control type that the distance between the optical axis is adjusted in conjunction with the focusing mechanism.

In the manual adjustment type, the distance between the optical axes of the lenses can be adjusted to the optimum value according to the distance between the main subjects and the distance between the main subjects and other subjects, but the focusing and the distance between the optical axes are performed separately. Although it is troublesome, it does not interfere with the shooting of landscapes or still lifes, but lacks rapid firing, and if the user does not fully understand the operation or operation of the optical axis distance adjusting mechanism, the setting of the optical axis distance may be wrong. It is difficult to say that it is easy to handle. Therefore, it can be said that an automatic optical inter-axis distance adjusting mechanism is more suitable for a stereo camera for a general user than that of a manual optical inter-axis distance adjusting mechanism.

The conventional automatic optical inter-axis distance adjusting mechanism is configured to automatically adjust the optical inter-axis distance in conjunction with the focusing adjustment so that the clocks of the left and right photographing lenses always coincide at the confocal distance, thereby obtaining a uniform optical inter-axis distance correction effect.

Assume the lens is one thin lens,

Focal Length of the Lens ------------------------------------ f

Distance from the subject to the main lens of the lens ---------- L

Distance from the focus position of the lens to the imaging position ----

Speaking of

△ if = f ² / (Lf) -------------- (Equation 1)

The distance between the principal point of the lens and the film surface is f + Δif.

Fig. 22 shows the movement trajectories of the main points of the photographing lenses for matching the clocks of the left and right photographing lenses at the focal length, and each shift amount Sl of the left and right lenses for matching the clocks of the left and right photographing lenses at the focal length is If the pitch of the left and right exposure surface of the stereo camera is P,

Sl = (P / 2) × (f + Δif) / (L + f + Δif) --- (Equation 2)

Can be obtained as

The table in Fig. 23 shows the shift amount Δif in the optical axis direction and the shift amount in the optical axis perpendicular direction when the focal length of the lens is 36 mm and the left and right exposure surface pitch P is 66 mm. The relationship of (Sl) is shown. As the distance L of the focused subject decreases, when the left and right photographing lenses are moved in a direction approaching each shift amount Sl, the movement trajectory of the main points of the photographing lenses shows a gentle curve, and the focusing distance The left and right shots of the lens always match.

In addition, the conventional automatic optical inter-axis distance adjusting mechanism is configured to move the principal point of the photographing lens to move the trajectory image based on the above equation by means of a cam or guide, and in fact, almost all of the focusing and optical-axis distance adjustments are linked. In this case, there is a problem that a satisfactory optical axis distance correction effect is not obtained.

The reason for this problem is that all subjects in the screen are rarely at a focal length, and in most cases, subjects are mixed at various distances. For example, when photographing a landscape focusing on infinity, some objects are often photographed in front of an infinity object. Also, in close-up photography, for example, when photographing flowers of a flowerbed obliquely from above, the flowers that are in front of the flowers in the center of the focused screen also enter the screen, focusing on the eyes of the model and focusing on the front person. When taking a picture, the model's nose is positioned ahead of the focal length.

In the case of the stereo slide in which the subject image which has a strong influence on the matching of the left and right images as described above is closer than the subject image of the focal length, the stereoscopic image of the near subject is formed in front of the stereo window and looks unnatural. In order to correct this, it is necessary to mask the outer edges of the left and right screens when mounting the film as in the prior art, or to correct the perspective by adjusting the adhesion pitch of the left and right films. In this way, the operation of the conventional automatic optical axis distance adjusting mechanism is not to be perfect.

Therefore, there is a technical problem to be solved in order to provide a stereo camera having a more practical optical axis distance adjustment mechanism so that anyone can easily take a stereo picture showing the best stereoscopic effect, the present invention is It aims to solve.

In order to achieve the above object, the present invention proposes that two photographing lenses are mounted on separate lens boards, and the distance between the left and right lens boards is changed in conjunction with the forward and backward movement of the lens board by a focus adjustment operation. In a stereo camera provided with an automatic optical inter-axis distance adjusting mechanism in which the optical axis intervals of two photographic lenses are corrected according to the focal length,

The movement trajectory of the two photographing lenses is a position in which the optical axis interval of the two photographing lenses is narrower than the pitch of the left and right exposure screens at the infinity focus adjustment position, and preferably, the clock of the two photographing lenses is located from the principal point of the photographing lens. The position within the range of coincidence intervals at a distance of 2 to 3m in front of the lens, and the positions of the optical axis intervals at or near the position where the clocks of the two photographing lenses coincide at the focal length at the shortest focusing position. It is to provide a stereo camera that is a symmetrical straight line connecting.

Further, the movement trajectory of the two photographing lenses is a position where the optical axis interval of the two photographing lenses is narrower than the pitch of the left and right exposure screens at an infinite focus adjustment position, and preferably, the clock of the two photographing lenses is the main point of the photographing lens. The position within the coincidence interval range from 2 to 3m in front of the optical axis from the optical axis, and the optical axis spacing position where the clocks of the two photographing lenses coincide at the focal length at the shortest focusing position, or the coincidence at the focal length It is to provide a stereo camera which is a circularly symmetrical arc passing through an optical axis interval position that is slightly narrower than the optical axis interval.

1 shows an embodiment of the present invention, which is a graph showing a linear movement trajectory of a photographing lens.

2 shows an embodiment of the present invention, which is a graph showing a linear movement trajectory of a photographing lens.

3 is a graph showing an embodiment of the present invention and showing a setting allowable range of the linear movement trajectory of the photographing lens.

4 shows an embodiment of the present invention, and is a graph showing the arc movement trajectory of the photographing lens.

Fig. 5 shows an embodiment of the present invention and is a graph showing a setting allowable range of the arc movement trajectory of the photographing lens.

Fig. 6 shows an embodiment of the present invention, which is an explanatory graph showing the arc movement trajectory of the photographing lens.

7 is an explanatory diagram of a calculation for obtaining arbitrary lens position coordinates on an arc.

FIG. 8 is a table showing a circular arc trajectory of FIG.

Fig. 9 shows an embodiment of the present invention and is an exploded view of a linearly movable automatic optical axis distance adjusting mechanism.

10 is a cross-sectional view of a linearly movable stereo camera.

FIG. 11 is a view for explaining the configuration of a finder of the stereo camera of FIG. 10; FIG.

FIG. 12 is a configuration diagram illustrating an automatic optical inter-axis distance adjusting mechanism of the stereo camera of FIG. 10. FIG.

Figure 13 is a configuration diagram of the circular arc moving automatic optical axis distance adjusting mechanism.

14 is a longitudinal cross-sectional view showing a connection structure of the lens board and the camera body of FIG.

Fig. 15 is a sectional view of an arc-type stereo camera.

16 (L) and (R) are diagrams illustrating the configuration of the parallel link mechanism of the stereo camera of FIG. 15, respectively.

Fig. 17 shows another embodiment, a sectional view of an arc-type stereo camera.

18 (L) and 18 (R) are schematic diagrams of the parallel link mechanism of the stereo camera shown in FIG. 17, respectively.

Fig. 19 shows another embodiment, a sectional view of an arc-type stereo camera.

20 (L) and (R) are explanatory diagrams showing films taken by a conventional stereo camera, respectively.

21 is an explanatory diagram showing screen loss of a conventional stereo camera.

Fig. 22 is an explanatory diagram showing a curve moving trajectory of a lens when the clocks of the left and right lenses are matched at the focal length.

Fig. 23 is a numerical table of the distance between optical axes where the clocks of the left and right photographing lenses coincide at the focal length.

* Explanation of symbols for main parts of the drawings

1: Slide base 2L, 2R, 22: Slider

3L, 3R, 38L, 38R, 42L, 42R: Lensboard

4L, 4R: Guide groove 5L, 5R: Rib

6L, 6R, 23, 45L, 45R: Parallel Groove

7L, 7R, 24, 43, 67: circular eccentric cam

14, 31, 41, 61: stereo camera 16: finder lens

33L, 33R: Synchronous gear

34, 64: focusing axis

39: bell crank lever

40, 47, 62: link 46: camera body

48: leaf spring 66: cam follower link

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail according to drawing. First, when viewing a stereo slide with a stereo slide viewer, the relationship between the distance between the left and right windows of the stereo slide mount and the distance seen by one window and the distance of the stereoscopic image of the subject will be described.

As stereo slide which we photographed with conventional automatic optical axis distance adjustment type stereo camera that clock of right and left lens coincides at confocal distance, clock of right and left lens coincides at confocal distance, stereoscopic image of subject at confocal distance and stereo The window is equidistant.

As shown in Fig. 22, for example, when photographing an infinity landscape, since the lens shift amount Sl is zero, the pitch on the left and right screens is the same on the same infinity subject on the left and right screens, and the stereo The window looks infinity in the same way as the subject in infinity, and the object in front of the infinity is located in front of the stereo window and feels unnatural. Therefore, it can be inferred that a better result will be obtained by shifting the photographing lens so as to match the clock of the left and right photographing lens at a near distance rather than the focusing distance.

Therefore, first, the shift amount of the photographing lens in the case where the focus is adjusted to infinity is considered. Like the conditions described in the prior art,

Focal length f = 36mm

Left and right exposure surface pitch P = 66 mm

Image pitch of the focal length subject = Pi

In this state, in the state where focus is adjusted to infinity, for example, the shift amount Sl of the photographing lens in which the stereoscopic image of the subject at a distance of 1 m and the window of the stereo are equidistant is about 1.15 mm from Equation 2. to be. At this time, since the infinite subject image is moved in the same direction as the shift amount of the photographing lens on the exposure surface of the film, it is shifted by 1.15 mm in the approaching direction, respectively, and the pitch Pi on the infinite subject of the left and right films is reduced by 2.3 mm. The image on the exposure surface of the stereo camera is an inverted image inverted up, down, left, and right, and the upright image of the film photographed with the shift amount Sl (= 1.15 mm) is placed on the stereo slide mount. When mounted in the state of standing, the pitch Pi on the infinity subject increases by 2.3 mm from the left and right screen pitch P (66 mm).

If the pitch Pi on the subject at the focal length (in this case, infinity) becomes significantly wider than the left and right screen pitches P, it is natural to look unnatural, but to what extent is the range allowed? In order to investigate, the experiment which observes the various photographing samples from which the shift amount of a photographing lens differs was performed. As a result, evaluation was obtained that the difference between the left and right screen pitches and the image pitch of the same subject on the left and right screens is generally within about 1.2 mm.

That is, when the shift amount Sl of the left and right photographing lenses for infinity shooting is 0.6 mm or less under the above conditions, the difference between the screen pitch and the pitch on the same subject of infinity on the left and right screens is 1.2 mm. When the image of infinity is not seen unnaturally and the near subject image is in the screen, a good three-dimensional effect can be obtained.

Therefore, the shift amount of the photographing lens in the case of infinity is set to 0.6 mm, but this 0.6 mm value is almost the same as the shift amount Sl seen at equidistant distance from the subject whose stereo window is about 2 m when inverted from Equation 2. will be.

Next, the shift amount of the photographing lens at the shortest focusing distance is considered. In the shortest focusing distance, as in the case of infinity shooting, the condition that the pitch between the subjects at the focusing distance is extended about 1.2 mm from the pitch of the window of the stereo slide mount is applied, and the shortest focusing distance L = 360 mm.

Δif = f ² / (Lf) = 36 ² / (360-36) = 4 mm

Then, the amount of movement of the image Si on the left and right screens is 1.2 / 2 = 0.6 mm,

The shift amount Sl of the photographing lens at that time is

Sl = (P-(L × Pi) / (L + f + Δif)) / 2

= (P-(L × (P-1.2)) / (L + f + Δif)) / 2

= (66- (360 × (66-1.2)) / (360 + 36 + 4)) / 2 = 3.84 mm

Further, the distance Lw where the clocks of the left and right photographing lenses coincide, that is, the distance seen by one window of the left and right windows of the stereo slide mount is as follows.

Lw = (f + Δif) (P-2Sl) / 2Sl

= (36 + 4) (66-2 × 3.84) / 2 × 3.84 = 304 mm

1 shows a movement trajectory of only the left photographing lens. However, the lens position of the infinity photographing and the lens position of the shortest confocal distance are connected in a straight line. It is set at a distance of about 2 m from the main point, and is set at a position of 304 mm at 360 mm which is the shortest focusing distance.

In the above example, in the entire range of the focusing range, the shift amount inward is larger than the track L _REF of the lens of the conventional auto-optical distance-adjustable stereo camera indicated by dotted lines, and most photographing films correct the film attachment position. Alternatively, the mount can be mounted on a stereo slide mount without masking part of the screen.

1, the inclination angle θ of the linear trajectory with respect to the optical axis is

θ = tan ^-1 (3.84-0.6) / 4 = tan ^-1 0.81 = 39 ° 00 '

And the lens shift amount Sl in the optical axis perpendicular direction is

Sl = 0.6 + Δif × tanθ (θ = 39 ° 00 ')

Can be obtained as

Here, for example, when the shift amount Sl of the photographing lens in the case of focusing at a distance of 1m is obtained,

Δif = f ² / (Lf) = 36 ² / (1000-36) = 1.344 mm

Sl = 0.6 + 1.344 × tan39 ° 00 '= 1.688 mm

Since the amount of movement on the infinite screen is equal to the shift amount Sl of the photographing lens, when the background of the infinite circle is captured in the screen when the focus is 1 m, the left and right screens are displayed. The interphase pitch of the infinity background of the image is enlarged by about 3.4 m (= 2Sl) with respect to the screen pitch.

Therefore, since it exceeds the recommended range (within about 1.2 mm) of the difference between the above-mentioned screen pitch and the pitch of the subject image, it is desirable to consider that the far background is not to enter the screen as much as possible during close-up photography.

Although the lens movement trajectory is focused on the performance of close-up photography, a general user often takes a subject at a distance of 1 m or more, and many cameras have a shortest focusing distance of about 1 m. In these cases, the shift amount is reduced as a whole than that in Fig. 1 (for example, as shown in Fig. 2, the shift amount Sl = 0.39 mm in which the stereo window is shown at 3 m at the infinite focus adjustment position), When the inclination of the movement trajectory with respect to the optical axis of the photographing lens is reduced, it is possible to alleviate the problem that the image pitch of the background becomes excessively large when the background of the near subject is photographed on one screen.

The movement trajectory of the photographing lens shown in Fig. 2 intersects the conventional curve trajectory L _REF at a focal length (Δif ㎜ 2.0 mm) of about 700 mm, and most of the film other than the close-up image is mounted when mounted. Correction is unnecessary, and only the film of a close-up photography needs to perform a correction of a mount position or a mask process of a screen as needed.

Therefore, depending on whether focusing on close-up photography or shooting on a general distance, or depending on conditions such as the shortest focusing distance of the photographing lens, the range of the photographing lens within the range between the linear trajectory of FIG. 1 and the linear trajectory of FIG. The trajectory can be set, and when the trajectory is set within the range between the two straight lines as shown in Fig. 3, a better optical axis distance correction effect is obtained than in the conventional stereo camera. In addition, since the photographing lens is linearly moved, the structure of the optical axis distance adjusting mechanism is simplified and high operation accuracy can be obtained.

In the above, the case where the movement trajectory of the photographing lens is made straight is explained. However, as another optical axis distance adjusting mechanism that can expect a very accurate operation, the movement trajectory of the photographing lens is controlled by a parallel link mechanism combining a plurality of levers or links. We can think of to do with arc.

When the circular arc trajectory is adopted, the circular arc trajectory having the same radius as the conventional curve trajectory or the larger radius is used to shift the photographing lens inward at the infinite focal adjustment position, and shift the lens as the lens is carried. It may be reduced to an arc trajectory in which the distance of the stereoscopic image of the confocal subject and the distance of the stereo window approximately coincide at the shortest shooting distance. However, in this case, since the circular arc radius is large, the length of the link is long, and it is easy to install in a large camera, but it is not suitable for a small camera.

Therefore, as shown in FIG. 4, in contrast to the conventional curve trajectory L _REF , when the circular arc centered on the middle side of the left and right photographing lenses is used as the movement trajectory of the photographing lens, the arc radius can be reduced. have. Then, the shift amount is set within a range of 0.39 to 0.6 mm so that the stereo window is shown at a distance of approximately 2 to 3 m at the infinite focus adjustment position, and the shift of the conventional curve trajectory L _{REF at the} shortest focusing distance. It is preferable to set the shift positions within a relatively narrow allowable range including the positions, but these positions should be set according to the target shift characteristics or conditions such as the focal length or the shortest focusing distance of the lens, and those of the linear trajectory type. Likewise, the range is not limited numerically.

Accordingly, although circular arcs A, B, and C illustrated in FIG. 5 can be set to various arcs having different arc centers or circular arc radii, the conventional curved trajectory L _REF as in the range of the linear trajectory shown in FIG. 3. Of course, it is naturally limited to a range that does not significantly shift from.

In Fig. 5, arc A represents the movement trajectory of the lens of the stereo camera according to claim 7, wherein the window of the stereo is shown at a distance of about 2 m at infinity focus, and at any intermediate position within the focus adjustment range. The stereoscopic image of the subject at the focal length (for example, 700 mm) is seen equidistant from the stereo window, and the shift amount is shorter on the near side, but at the shortest focal length, the stereoscopic image of the subject at the focal length is equidistant from the stereo window. It is a visible trajectory.

The arc B represents the movement trajectory of the lens of the stereo camera according to claim 8 of the claims, and the stereo window is shown at a distance of about 2 m at infinity focus, and the stereoscopic object of the subject at the focal length at an intermediate position within the focusing range. The image is seen at an equidistant distance from the stereo window, so that on the near side, the stereoscopic image of the subject at the confocal distance is seen again behind the stereo window. Since arc B has a smaller radius of arc than arc A, it is possible to shorten the link length.

Arc C represents the movement trajectory of the lens of the stereo camera according to claim 9 of the claims, shifts the radius center of arc B to the inner side (right side in the drawing), increases the shift amount over the entire area, and the conventional curve trajectory. Do not touch (L _REF ).

Here, for example, a calculation for obtaining the trajectory of arc D shown in FIG. 6 will be described. As in the above example, the focal length of the lens is 36 mm, the left and right exposure surface pitch P ₁ is 66 mm, and when the focus is adjusted infinity, the distance at which the clocks of the left and right lenses coincide is 2.5 m. When the lens position is set to O ', the shift amount of the point O' is expressed from Equation 2.

Sl = (66/2) × 36 / (2500 + 36) = 0.468 mm

The distance Xo 'between the points O and O' is about 0.47 mm. The point where the arc of the movement trajectory of the lens intersects the conventional curve indicated by the dotted line is Q, the current O'Q is drawn between the circular arcs O'Q, and the current PQ is similarly drawn between the arcs PQ. Then, when the intersection A is drawn from the midpoint S of the current O'Q, and the intersection B is drawn from the midpoint T of the current PQ, the intersection becomes the center V of the arc O'QP.

The coordinate position of the point O 'is x = 0.47, y = 0, and when Δif of the point Q is 2 mm, which is an intermediate point of 4 mm of the movement range in the optical axis direction of the lens, the x coordinate of the point Q is shown in FIG. From the table, x ≒ 1.7368, the y coordinate is y = 2.

The difference between the x value of point O 'and point Q is

x _Q -x _{O '} = 1.7368-0.47 = 1.2668

the difference in y is

y _Q -y _{O '} = 2

The slope ratio of the current O'Q to the optical axis is 1.2668 / 2 = 0.6334.

The coordinate position of point S is

x = (0.47 + 1.7368) / 2 = 1.1034

y = 2/2 = 1

And the y value when x = 0 on the line A is

y = 1 + 1.1034 × 0.6334 = 1.69889356

And the formula representing the repair line A is

y = -0.6334x + 1.69889356

Becomes

Similarly, the difference between the y values of the point P and the point Q in the line B is

y _Q -y _{O '} = 4-2 = 2

The difference of x value is from the table of FIG.

x _P -x _Q = 3.30-1.7368 = 1.5632

The slope ratio of the current PQ to the optical axis is

1.5632 / 2 = 0.7816

Becomes

The coordinate position of point T is

x = (3.30 + 1.7368) / 2 = 2.5184

y = (4 + 2) / 2 = 3

And the y value when x = 0 on the line B is

y = 3 + 2.5184 × 0.7816 = 4.96838144

Where repair B is

y = -0.7816x + 4.96838144

Can be displayed as

Since the coordinates coincide at the intersection of the repair lines A and B,

-0.6334x + 1.69889356 = -0.7816x + 4.96838144

Binaryly

-0.6334x + -0.7816x = 4.96838144-1.69889356

Put together

0.1482x = 3.26948788

x = 22.06132173

Also,

y = -0.7816 × 22.0613 + 4.9683 = -12.2748

X _V = 22.0613 mm

Y _V = -12.2748 mm

Since the point O 'is located on the arc D, the radius R _V of the arc D is

R _V = √ ((X _V -X _{O '} ) ² + Y _V ² ) = √ ((22.0613-0.47) ² + 12.2748 ² )

= 24.83656 (mm)

to be.

In addition, arbitrary lens positions a on the circular arc shown in FIG. 7 are obtained from the radius R _V and the center coordinates X _V and Y _V of the circular arc.

βa = sin ^-1 ((△ if-Y _V ) / R _V )

Xa = X _V -R _V cosβa

The calculated values of Δif and S1, βa, and Xa of the arc D are shown in the table of FIG. 8.

In this example, the stereo window is set to 2.5 m at infinity adjustment, and when the focus is adjusted to about 700 mm, the stereo window is shown at about 700 mm equal to the focal length, and is closer than about 700 mm. If the focus is on, the stereo window will appear slightly farther than the focal length, but the difference is so small that the amount of offset that must be corrected at mount time is very small. In addition, when the circular arc data shown in the table of FIG. 8 is applied to a stereo camera whose shortest focusing distance is farther than 700 mm, an optical axis distance correction effect that is optimal in almost all situations can be obtained.

Next, the specific structure of the automatic optical inter-axis distance adjusting mechanism will be described. Fig. 9 shows an automatic optical inter-axis distance adjusting mechanism for linearly moving the lens board, wherein reference numeral 1 is a slide base, 2L and 2R are sliders, and sliders 2L and 2R and the lens boards 3L and 3R at the front are integral. Are combined. On the upper surface of the slide base 1 fixed to the bottom part in the camera main body, left and right symmetrical linear meandering guide grooves 4L and 4R are formed, and the sliders 2L and 2R are provided. On the lower surface, ribs 5L and 5R forming treatments with the guide grooves 4L and 4R are formed.

Straight parallel grooves 6L and 6R are formed in the inner parts of the left and right sliders 2L and 2R, that is, the middle side of the optical axis of the left and right photographing lenses, and the direction of the parallel grooves 6L and 6R is a rib ( It is perpendicular to the direction of 5L, 5R).

The inner part which formed 6 L of parallel grooves of the left slider 2L is cut out by the upper half, becomes the thickness of 1/2 of the plate | board thickness of the slider 2L, and is the inner part of the right slider 2R. The lower half of the figure is cut out to be half the plate thickness of the slider 2R, and the inner portions of the left and right sliders 2L and 2R in the state where the sliders 2L and 2R are attached to the slide base 1 are shown. These overlap each other.

The bearings 8 of the lens movement cams 7L and 7R are attached to the bearing attachment hole 1a in the center of the slide base 1. The cams 7L and 7R are attached to the upper and lower ends of the focus adjusting shaft in two stages, and a pulley 9 is attached to the lower portion of the focus adjusting shaft.

The left cam 7L and the right cam 7R are circular eccentric cams of the same shape, the diameters of which are substantially the same as the axes of the parallel grooves 6L, 6R of the sliders 2L, 2R, and the left and right guide grooves. The left cam 7L is coupled to the parallel groove 6L of the left slider 2L, and the right cam 7R is attached to the focus adjustment shaft with the same rotation angle difference as the angle formed by 4L and 4R. Engaged in the parallel groove 6R of the right slider 2R.

The focus adjusting knob 11 is fixed to the head of the pulley shaft 10 supported by the camera body (not shown), and the pulley 12 attached to the lower portion and the pulley of the focus adjusting shaft are attached to the lower portion. The wire 13 or the belt is wound around (9).

When the focus adjustment knob 11 is rotated, the cams 7L and 7R rotate in conjunction with each other, and the left and right sliders 2L and 2R are synchronized to meander along the guide grooves 4L and 4R. The distance between the optical axes is automatically adjusted in conjunction with the focus adjustment. As described above, the directions of the parallel grooves 6L and 6R are perpendicular to the directions of the guide grooves 4L and 4R, and the respective movement directions of the sliders 2L and 2R and the pressures of the cams 7L and 7R are different. Since the action directions coincide, the sliders 2L and 2R slide smoothly.

Moreover, although it is a well-known means, when the gun wire 13 is fixed to the pulleys 9 and 12 at one point of the outer periphery of the pulleys 9 and 12, the slippage of the wire 13 is prevented. This can be prevented and the pair of pulleys 9 and 12 can be synchronously rotated reliably.

FIG. 10 shows a three-lens type stereo camera 14 equipped with the linear optical axis adjusting mechanism of FIG. 9, wherein the finder lens 16 is located in the center of the front surface of the camera body 15. ) And a pair of photographing lenses 17L and 17R are arranged in a horizontal line, and the optical axes of the three lenses 16, 17L and 17R are located in parallel on the same plane. A focal plane shutter (not shown) is provided directly in front of the exposure surface behind the photographic lenses 17L and 17R. As shown in FIG. 11, a 45 ° reflex mirror ( a reflex mirror 18 is fixed. Light rays incident on the finder lens 16 are imaged on the upper focusing plate 19 through the reflex mirror 18, and the penta prism is similar to a single-lens reflex camera. The upright image can be observed through the 20 and the eyepiece 21.

Fig. 12 shows the slider 22 to which the finder lens board is attached and the lens boards 3L and 3R of the photographing lens. The slider 22 is provided with parallel grooves 23 in the left and right directions, and the cam for moving the photographing lens is shown. Similarly to 7L and 7R, the circular eccentric cam 24 for moving the finder lens provided on the focus adjustment shaft is coupled to the parallel groove 23. Thereby, the three lenses 16, 17L, and 17R move back and forth in synchronization with the rotation of the focus adjustment shaft, and the state of focus adjustment can be determined by the confocal state of the image on the focus plate 19. FIG.

The finder lens 16 may have the same focal length as the photographing lenses 17L and 17R. However, when the finder lens having a shorter focal length than the photographing lens is used, the occupied space of the finder portion can be reduced. In this case, the size of the focusing plate 19 shown in FIG. 11 is reduced in size to match the image angle of the image on the focusing plate with the screen angle of the exposure screen by the photographing lenses 17L and 17R, and the amount of movement of the finder lens. It is preferable to design the shape and dimensions of the finder lens shift cam 24 and the width of the parallel groove 23 of the slider 22 so as to satisfy the expression? If = f ² / (L-f).

FIG. 13 shows an example of a focusing mechanism and an optical-axis distance adjusting linkage mechanism of a stereo camera having an arc of movement of a photographing lens as an arc, and two vertical axes 32L and 32R on the main body frame (not shown) of the stereo camera 31. The rotatable attachments of the same shape and synchronous gears 33L and 33R attached to the upper portions of the two vertical shafts 32L and 32R are engaged with each other.

The focus adjustment shaft 34 disposed in front of the vertical axes 32L and 32R includes a pinion gear 35, a cam 36 for moving the movable mirror of the range finder, and a focus adjustment knob. (37) is attached and the pinion gear 35 is meshed with one synchronous gear 33R.

Bell crank levers 39 are fixed to the vertical shafts 32L and 32R, respectively, and the upper and lower bell crank levers 39 disposed on the outer sides of the vertical shafts 32L and 32R, respectively, have a central axis thereof. It is supported by the upper and lower bearings provided in the main body frame (not shown). The front ends of the four levers 39 are respectively rotatably attached to the inner and outer ends of the upper and lower surfaces of the left and right lens boards 38L and 38R, respectively. The rear end of each of the two levers to be treated is connected by a link 40 to form a parallel link mechanism.

Since the lever pivot points of the left and right lens boards 38L and 38R are located outside the vertical axes 32L and 32R, respectively, when the focus adjustment knob 37 is rotated, the left and right lens boards 38L and 38R are photographed. The arc trajectory image is moved in parallel while maintaining a right angle with respect to the optical axis of the lens. In addition, the range finder cam 36 can rotate the movable mirror of the range finder to visually recognize the focus adjustment state. Since the structure of the range finder is well known, its explanation is omitted.

Fig. 14 shows the attachment structure of the lens boards 38L and 38R to the camera body, and the external light (by the upper and lower ends of the lens board is in contact with the upper and lower wall surfaces of the body of the stereo camera 31 and slides). The external light is blocked and the position of the lens boards 38L and 38R in the vertical direction is maintained accurately. As means for shielding the gap between the side of the lens board and the camera body, a thin plate spring, which will be described later, is attached to the camera body, and the plate spring is elastically bonded to the side of the lens board. Shield the gap between the lens board and the camera body.

The radius of the circular arc trajectory along which the lens boards 38L and 38R move is determined by the distance between the lever pivot point of the lens boards 38L and 38R shown in FIG. 13 and the center of the vertical axis 32L and 32R. By the positions of the centers of the vertical axes 32L and 32R, various arc trajectories as shown in Figs. 5 and 6 can be realized.

In addition, although the link 40 which connects the lever 39 may be abbreviate | omitted, when the link 40 is abbreviate | omitted, the straight line which passes two lever pivot points of the left and right both sides of the lens boards 38L and 38R is a vertical axis. When approaching (32L, 32R) and approaching the dead point of the parallel link mechanism, there is a possibility that the smoothness of the operation may be reduced, but the other end of the bell crank lever 39 is connected to the link 40. This eliminates dead spots and works smoothly over the entire range of rotation.

Fig. 15 shows another embodiment of the stereo camera. The stereo camera 41 synchronously drives the left and right lens boards 42L and 42R by the cams 43, so that the photographing lenses 44L and 44R can be moved. The movement trajectory is the arc. 16 (L) and (R), the inner side portions of the left and right lens boards 42L and 42R have parallel parallel grooves 45L and 45R in a direction orthogonal to the optical axes of the photographing lenses 44L and 44R, respectively. ) Is formed.

And similarly to the lens boards 2L and 2R in Fig. 12, the constituent parts on the inner side of the left lens board 42L are cut out by half of the upper portion, and have a thickness of 1/2 of the plate thickness of the lens board 42L. The lower half of the constituent part of the right lens board 42R is also cut out to be 1/2 the thickness of the plate thickness of the lens board 42R, and the cutout portions of the left and right lens boards 42L and 42R are overlapped. , Respectively, to the camera body 46 via two links 47 having the same length.

In the parallel grooves 45L and 45R of the left and right lens boards 42L and 42R, one circular eccentric cam 43 disposed in the center of the base frame 46 is inserted, and the focus adjustment with the cam 43 attached thereto is carried out. By rotating the axis, the left and right lens boards 42L and 42R move on the arc trajectory image symmetrically.

The side surfaces of the lens boards 42L and 42R are formed in a circular arc shape opposite to the movement trajectory, and the edges of the front ends of the leaf springs 48 attached to the camera body 46 are disposed on the lens boards 42L and 42R. Since it is elastically bonded to the side surface of the lens), no gap is generated between the leaf spring 48 and the lens boards 42L and 42R regardless of the focusing position of the lens board. , Water droplets do not break.

17 and 18 show another embodiment, and the stereo camera 61 has a shorter link length than the stereo camera 41 of FIG. 14. The two links 62 on the left and right sides are pivot points thereof, and the two links 62 in the center are rotatably mounted on the focus adjustment shaft 64.

The left lens board 65L is connected to the front end of the two links 62 constituting the left parallel link mechanism, and the right lens board 65R is connected to the front end of the two links 62 constituting the right parallel link mechanism. The other ends of the two sets of links are connected by cam follower links 66L and 66R, respectively.

The circular eccentric cam 67 is coupled to the parallel grooves 68L and 68R of the two cam follower links 66L and 66R overlapping each other, so that when the cam 67 is rotated, the cam follower links 46L and 46R are rotated. By virtue of this, the lens boards 65L and 65R on the left and right sides move in a circular arc in contrast, and the operation thereof is the same as that of Fig. 14, but the radius of the arc is smaller because the lever is shorter than that of Fig. 14.

In addition, the stereo camera 71 shown in FIG. 19 rotatably attaches the front parts of the two left and right links 72 constituting the parallel link mechanism to the camera main body 73, and respectively attaches the rear parts of the links 72 to each other. It is rotatably attached to the rear part of the lens boards 74L and 74R, and the radial center of the movement trajectory of the left and right lens boards 74L and 74R is located outside the respective optical axes, and the curve trajectory of the conventional automatic optical inter-axis distance adjusting mechanism is provided. The arc trajectory is almost similar to.

In addition, the applicant of the present application, the combination of the reflex mirror and one or multiple prisms, respectively, the inner half of the inverted image incident through the two photographing lenses (left half of the field of view of the left photographing lens and the right photographing lens) We have already proposed a stereo camera that synthesizes one finder screen by projecting the right half of the field of view onto one focal plane. This stereo camera is capable of judging the state of the focus as the left and right half images in the finder approach or move away from each other according to the focal length of the photographing lens.

In the stereo camera provided with the optical axis distance adjusting mechanism, since the left and right 1/2 images in the finder approach or move away from each other even by the change in the optical axis distance between the photographing lenses, the left and right half to the finder system. Although it is necessary to provide a means for correcting the image pitch of the image, in order to cope with this need, the clock of the left and right viewfinder system is automatically corrected by moving part or all of the hybrid prism back and forth in conjunction with the change of the optical axis distance. Also proposed is a stereo camera with a mechanism to enable focusing.

When the above-described prism finder is mounted on the stereo camera of the present invention, similar to the circular eccentric cam 24 for shifting the finder lens, the prism shifting cam is attached to the focus adjustment shaft, and the focus / optic interval adjustment and By interlocking part or all of the prism back and forth so that the image pitch of the left and right half of the finder system is corrected, very accurate focus adjustment is possible.

In addition, this invention is not limited to said embodiment, More various changes are possible in the technical scope of this invention, and it is natural that this invention affects those modified.

As described above, the stereo camera of the present invention is a stereo camera in which the distance between the optical axes of the photographing lenses is automatically adjusted according to the photographing distance. By setting the linear trajectory or the arc trajectory in accordance with the circular trajectory and the purpose of using the stereo camera or the usage of the photographing lens, almost no unnaturalness of perspective often seen in the conventional stereo camera is generated, and anyone can easily It is the invention which can take the stereo picture which shows the best stereo effect, and contributes to the improvement of the practical performance of the stereo camera.

Claims (15)

Each of the two shooting lenses is mounted on a separate lens board, and the distance between the left and right lens boards changes in conjunction with the front and rear movement of the lens board by the focus adjustment operation, and the optical axis interval of the two shooting lenses is the confocal distance. In a stereo camera provided with an automatic optical axis distance adjusting mechanism corrected according to The movement trajectory of the two photographing lenses is a position where the optical axis spacing of the two photographing lenses is narrower than the pitch of the left and right exposure screens at an infinite focus adjustment position, preferably, the field of view of the two photographing lenses. In the range of the optical axis interval coinciding at a distance of 2 to 3 m along the optical axis from the main point of the photographing lens and the field of view of the two photographing lenses coinciding at the focal length at the shortest focusing position. A stereo camera, characterized in that it is a symmetrical straight line connecting the optical axis spacing position or the position near the position. The optical trajectory range of claim 1, wherein the movement trajectories of the two photographing lenses coincide with each other at a distance of 2 to 3 m along the optical axis from the main point of the photographing lens at the infinity focus adjustment position. A stereo camera having a horizontally symmetrical straight line passing through a position within the optical axis interval at which the clocks of two photographing lenses coincide at a confocal distance at an inner position and a shortest focusing position. The optical trajectory range of claim 1, wherein the movement trajectories of the two photographing lenses coincide with each other at a distance of 2 to 3 m along the optical axis from the main point of the photographing lens at the infinity focus adjustment position. A stereo camera having a bilaterally symmetrical straight line passing through the optical axis spacing positions where the clocks of two photographing lenses coincide at a confocal distance at an internal position and a focusing position of a subject about 1 m. The slider according to any one of claims 1 to 3, wherein the slider having the two lens boards is mounted to the camera body by a linear slide guide mechanism, and the inner portions of the two sliders are overlapped up and down, and the overlapping portion is provided. Parallel grooves which are displaced by 90 degrees with the direction of movement of each slider, are arranged in the center of the two sliders, and the two cams of the same shape are fixed to the focusing axis. The insertion diameter of the two cams is almost equal to the width of the parallel grooves, and the relative rotation angles are displaced and attached to each other in the same manner as the displacement angles of the two sliders in the moving direction, and one cam is coupled to the parallel grooves of the left slider, and the other By combining the side cam with the parallel groove of the right slider, the two lens boards are meandered forward and backward in left-right symmetry in conjunction with the rotation of the focusing axis. Stereo camera. Each lens is mounted on a separate lens board, and the distance between the left and right lens boards is changed in conjunction with the front and rear movement of the lens board by the focus adjustment operation, and the optical axis spacing between the two lens lenses is corrected according to the focusing distance. In the stereo camera equipped with the optical axis distance adjustment mechanism, The movement trajectory of the two photographing lenses is a position in which the optical axis interval of the two photographing lenses is narrower than the pitch of the left and right exposure screens at the infinity focus adjustment position, and preferably, the clock of the two photographing lenses is located from the principal point of the photographing lens. In this case, the position within the range of coincidence intervals at a distance of 2 to 3m in front of the lens, the optical axis spacing position where the clocks of the two photographing lenses coincide at the focal length at the shortest focusing position, or the optical axis spacing at which the field of view coincides at the focal length A stereo camera, characterized by a circularly symmetrical arc passing through a slightly narrower optical axis interval position. 6. The stereo camera according to claim 5, wherein the center of the radius of the arc moving trajectory is located on the middle side of the two photographing lenses. 7. The optical axis interval according to claim 6, wherein the arc movement trajectory of the two photographing lenses is coincident with the field of view of the two photographing lenses coincident at a distance of 2 to 3 m along the optical axis from the main point of the photographing lens at an infinite focus adjustment position. In the range, the focusing position of the subject about 1m back and forth, the field of view of the two optical lenses coincides at the focal length, and the field of view of the two photographing lenses is at the focal length at the shortest focusing position. A stereo camera, characterized in that it is a circularly symmetrical arc passing through a corresponding optical axis interval position. 7. The optical axis interval according to claim 6, wherein the arc movement trajectory of the two photographing lenses is coincident with the field of view of the two photographing lenses coincident at a distance of 2 to 3 m along the optical axis from the main point of the photographing lens at an infinite focus adjustment position. In the range, the focusing position of the subject about 1m back and forth, the field of view of the two optical lenses coincides at the focal length, and the field of view of the two photographing lenses is at the focal length at the shortest focusing position. A stereo camera, characterized in that it is a circularly symmetrical arc passing through a position slightly narrower than the coinciding optical axis spacing. 7. The optical axis interval of claim 6, wherein the circular motion trajectory of the two photographing lenses coincides at a distance of 2 to 3 m along the optical axis from the principal point of the photographing lens at the infinity focus adjustment position. In the range and the shortest focusing position, the clocks of the two photographing lenses pass through the optical axis spacing position that is slightly narrower than the optical axis spacing position that coincides at the focal length, and the clock coincides at the focal length in the entire range of the focusing range. A stereo camera, characterized in that the arc of right and left symmetry which becomes narrower than the optical axis interval. 10. The apparatus according to any one of claims 5 to 9, wherein the two lens boards are attached to the camera body through a plurality of links, respectively, to constitute two sets of parallel link mechanisms, and to move the two lens boards and the photographing lens. Stereo camera with trajectory as the left and right symmetry arc. 11. The stereo camera according to claim 10, wherein gears of the same shape are attached to rotational shafts of the two sets of left and right parallel link mechanisms so that the two gears mesh with each other, and the two sets of left and right parallel link mechanisms are synchronized. . 12. The lens according to claim 10, wherein the inner portions of the left and right lens boards attached to the two sets of the left and right parallel link mechanisms are vertically overlapped, and the two overlapped portions are provided with parallel grooves, each of which is approximately 90 degrees displaced from the optical axis direction. Place a focusing axis perpendicular to the middle of the board, attach a cam having an insertion diameter approximately equal to the width of the parallel groove to the focusing axis, couple the cam to the parallel grooves of the left and right lens boards, and rotate the focusing axis. The stereo camera is configured such that two lens boards move in circular motion in synchronization. The camera body and the lens of claim 4 or 10, wherein a leaf spring is attached to a lens board attachment portion of the camera body of the stereo camera, and the leaf spring is elastically bonded to the side surfaces of the left and right lens boards. Stereo camera shielding the gap with the board. The cam for moving a slider according to claim 4 or 10, wherein a slider mounted with a finder lens is slidably moved forward and backward between the two lens boards, and a slider moving cam is used as a moving means of the slider on a focus adjustment shaft for moving the lens board. And a linkage mechanism between the focus / optical axis adjustment of the two lens boards and the focus adjustment operation of the finder lens. The screen of the left half of the field of view of the left photographing lens and the right half of the field of view of the right side of the photographing lens are formed by a composite prism in accordance with claim 4 or 10. A prism-type finder for composing one finder screen by projecting onto a focusing plate of the lens, and mounting a part or all of the compound prism on a slider to support the slide back and forth, and to a focusing axis for moving the lens board. A slider camera is attached as a slider moving means, and a linkage mechanism is formed between a focus / optical axis adjustment of two lens boards and a clock correction operation of a complex prism.