JP3030236B2 - Optical device of stereoscopic imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device used for a stereoscopic imaging apparatus for obtaining a stereoscopic image utilizing binocular parallax.

[0002]

2. Description of the Related Art Conventionally, as a stereoscopic image pickup apparatus for picking up a stereoscopic image having a right and left parallax with a single image pickup device, there is, for example, one disclosed in Japanese Patent Application Laid-Open No. 57-62686.
However, the device disclosed in this publication requires a rotating mirror for alternately guiding left and right information to one image sensor at a field cycle, and has a disadvantage that the structure is complicated.

Further, as disclosed in Japanese Patent Application Laid-Open No. 58-84589, there is a method that uses a half mirror and two shutters that open and close at a field cycle without using a rotating mirror. However, this method does not require a complicated structure, but has the disadvantage that the amount of light is reduced by half due to the use of a half mirror.

[0004] In order to solve such a drawback, the applicant of the present invention forms a stereoscopic image by forming right-eye information and left-eye information having parallax on a single image sensor (CCD). In the stereoscopic imaging apparatus, a prior art was filed for a stereoscopic imaging apparatus in which the right-eye information and the left-eye information are formed into different left and right areas on the image sensor by an anamorphic optical system (Japanese Patent Laid-Open No. 7-723).
No. 84).

[0005]

However, in the above-mentioned three-dimensional image pickup apparatus, as shown in FIG.
It has been found that a phenomenon occurs in which each image overlaps at the boundary between the left and right images on the CD 100 (hereinafter, referred to as an overlap phenomenon), which causes a problem that the image area that can be stereoscopically viewed decreases.

The cause of the overlap phenomenon will be described below.

Here, a case is considered where the right-eye image is mixed with the left-eye image. The overlap depends on the angle of view of the lens, and as shown in FIG. 7A, when the angle of view θ is smaller than a certain angle ω, a part of the right-eye image (the area indicated by the dotted line in the figure) ) Is reflected by the second mirror 102R, and forms an image in the left-eye image area of the CCD 100. The luminous flux of the left-eye image other than the dotted line portion is reflected by the second mirror 1.
The light is reflected by 02L and is imaged on the left eye image area on the CCD 100.

That is, the CCD 100 is completely divided into a left-eye image area and a right-eye image area in terms of position, and the image formation positions of the right-eye image and the left-eye image that have passed through the anamorphic optical system must be completely separated. I have to
Each image overlaps near the boundary between the left and right images, and an overlap phenomenon occurs. On the other hand, a luminous flux having an angle of view θ of approximately 0 °, that is,
The on-axis luminous flux forms an image on the boundary line on the CCD 100, so that no particular problem occurs. Further, as shown in FIG. 7B, when the angle of view θ is equal to or larger than a certain angle ω, the overlap phenomenon does not occur.

In view of the above circumstances, an object of the present invention is to provide an optical device of a three-dimensional imaging device capable of reducing or eliminating an overlap phenomenon.

[0010]

In order to solve the above-mentioned problems, the optical device of the stereoscopic image pickup apparatus according to the present invention provides a right-eye information light through two apertures provided at a predetermined horizontal distance from each other. And the information light for the left eye, respectively, approach each information light by a reflective optical system having a reflective surface, the two information light passed through the reflective optical system, by a lens system, to the left and right different areas on a single image sensor In the optical device of the three-dimensional imaging device configured to form an image, the reflection optical system includes a non-reflection area for not guiding a light beam portion of the two information beams at a position close to each other to the imaging device. And

In the overlap phenomenon, the light beam portions of the left and right information beams at positions close to each other are guided to the image sensor, and the light beam portion of the right-eye image at the close position is imaged on the image area for the left eye of the image sensor. Further, the light flux portion at the close position of the left-eye image is formed on the right-eye image area of the image sensor. Therefore, as described above, by providing the non-reflection area for preventing the light flux portions of the two information beams at positions close to each other from being guided to the image sensor, the overlap phenomenon can be eliminated.

The non-reflection area can be realized by providing a light absorber on a reflection surface or an optical path of the reflection optical system.

The non-reflection area forms a non-light area on a plane perpendicular to the optical axis of the lens system. The horizontal width of the non-light area is preferably set to be equal to the on-axis light flux diameter determined by the aperture diameter of the lens system. If the horizontal width of the non-light area on a plane perpendicular to the optical axis formed by the non-reflection area is smaller than the on-axis light flux diameter determined by the aperture diameter of the lens system, the overlap phenomenon is reduced by the smaller amount. Will remain. On the other hand, if the horizontal width of the non-light area is larger than the on-axis luminous flux diameter determined by the aperture diameter of the lens system, the information light is cut by that large amount, and a strip-shaped non-light part on the image sensor is formed. Because it can be done.

When the stop diameter of the lens diameter in the stereoscopic imaging apparatus is set for indoor use, the horizontal width of the non-light area is fixed in accordance with the stop diameter of the indoor lens system. It should be left. Conversely, if the aperture diameter of the lens diameter in the stereoscopic imaging device is set for outdoor use,
The horizontal width of the non-light area may be fixed in accordance with the aperture diameter of the outdoor lens system.

A liquid crystal element as the light absorber and a liquid crystal driving means for driving the liquid crystal element may be provided so that the width of the non-reflection area of the liquid crystal element can be changed.

In the stereoscopic imaging apparatus having a configuration in which the aperture diameter of the lens system is changed, it is difficult to completely eliminate the overlap phenomenon or the band-shaped non-light partial phenomenon when the width of the non-reflection region is fixed. As described above, by forming the light absorber from a liquid crystal element and driving the same, the width of the non-reflection area can be changed in accordance with a change in the aperture diameter of the lens system. The lightless partial phenomenon can be completely eliminated.

The control for changing the width of the non-reflection area is performed, for example, by a user manually adjusting the display surface of the stereoscopic imaging device while viewing the display surface, or by operating a changeover switch for selecting between indoor and outdoor use. By doing so, the user may make a selection by himself / herself, or may automatically make the selection based on a signal indicating the aperture diameter of the lens system or a signal indicating the illuminance of the subject.

Further, the optical device of the stereoscopic imaging apparatus according to the present invention takes in the right-eye information light and the left-eye information light from two openings provided at a position horizontally separated by a predetermined distance, respectively. Optical apparatus of a stereoscopic imaging apparatus, in which the two light beams having passed through the reflective optical system are imaged in different regions on the left and right on a single image sensor by a lens system. In the above, the reflection optical system is provided with a reflection area for preventing a light flux portion of the information light beams at positions close to each other from being guided to the image pickup device. Even in such a configuration, the overlap phenomenon can be eliminated similarly to the above.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an optical device 1 of a stereoscopic image pickup apparatus according to this embodiment. This optical device 1
An anamorphic mirror 1 that is a reflection optical system, and right and left images that have passed through the anamorphic mirror 1
And a lens system 2 for forming an image on the CD 30.

The anamorphic mirror 1 includes a right-eye component and a left-eye component. An opening 2R is formed in the right eye component, and an opening 2L is formed in the left eye component. These two openings 2R and 2L are formed apart from each other by a predetermined distance in the horizontal direction. Right eye component comprises a first mirror 3R ₁ and the second mirror 3R ₂ Metropolitan for the right eye, left eye component and the first mirror 3L ₁ for the left eye second
Consisting of mirror 3L ₂ Metropolitan. These mirrors 3R ₁ , 3R ₂
, 3L ₁ and 3L ₂ are formed so as to produce images having different magnifications in the vertical and horizontal directions, and make the right-eye information light and the left-eye information light taken in from the openings 2R and 2L approach each other. At the same time, both information light beams are compressed to １ ／ in the horizontal direction.

The second mirror 3R ₂ for the right eye and the second mirror 3R for the left eye
The mirror 3L _2, with mutually attracted to each one end of the on the lens optical axis, are connected through a vertical flat surface 4 on the optical axis. The prism-shaped block is processed, and the second mirror 3R ₂ for the right eye and the second mirror for the left eye are formed on the block.
The mirror 3L ₂ and the flat surface 4 may be formed. From the flat surface 4, it can be considered that the joint end portion (shown by a dotted line in the figure) of the second mirrors 3R ₂ and 3L ₂ has been removed. In this embodiment, the flat surface 4 forms a non-reflection area. The flat surface 4 prevents the light beam portions of the left and right information beams at positions close to each other from being guided to the CCD 30. In the figure, the light beam portion cut by the flat surface 4 is indicated by a dotted line.

As described above, the luminous flux portions of the two information beams at positions close to each other are prevented from being guided to the CCD 30, so that the overlap phenomenon can be eliminated.

In this embodiment, the width D ₁ of the flat surface 4 in the horizontal direction is equal to the stop diameter D _{2 of the} lens system _2.
Is set equal to the on-axis light flux diameter D ₃ determined by In the figure, the on-axis light flux diameter D ₃ is larger than the aperture diameter D ₂ of the lens system 2. However, depending on the type of lens system, the on-axis light flux diameter D ₃ is smaller than the aperture diameter D _2. There is also.

Here, as shown in FIG. 2, when the horizontal width D ₁ of the flat surface 4 is smaller than the on-axis light beam diameter D _3a determined by the aperture diameter of the lens system 2, the smaller amount is used. The overlap phenomenon will remain. On the other hand, flat surface 4
Of the width D ₁ of the horizontal direction is greater than the axial light flux diameter D _3b which is determined by the aperture diameter the lens system 2, the larger amount corresponding information beam is insufficient, it is no light portion of the strip on the CCD30 Would. As described above, by setting the horizontal width D ₁ of the flat surface 4 to be equal to the on-axis light flux diameter determined by the aperture diameter D ₂ of the lens system 2, the overlap phenomenon and the belt-like shape can be obtained. Both the non-light partial phenomena can be eliminated.

When the aperture diameter of the lens in the stereoscopic image pickup apparatus is set for indoor use, the flat surface 4
The width D ₁ of the horizontal it is sufficient to fix in accordance with the said lens system 2 of the stop diameter D ₂ for interior. Conversely, if the aperture diameter of the lens diameter in the stereoscopic imaging device is configured for outdoors, the combined width D ₁ horizontal direction of the flat surface 4 to the aperture diameter D ₂ of the lens system for outdoor It should be fixed.

(Embodiment 2) In this embodiment, the non-reflection area is not the flat surface 4 as in Embodiment 1 but the second mirrors 3R ₂ and 3L _{2 as} shown in FIG. The light absorbers 5 and 5 are arranged at the joint end portions of. As the light absorbers 5, 5, for example, a black paint or a black seal can be used.

As described above, also when the light absorbers 5 and 5 are used, the overlap phenomenon can be eliminated similarly to the first embodiment. In this embodiment, the size of the non-light area on the plane perpendicular to the optical axis formed by the light absorbers 5 is the left end of each of the light absorbers 5 in the drawing. It depends on the width between the parts.

(Embodiment 3) In this embodiment, as shown in FIG. 4, a non-reflection area is formed by light absorbers 6, 6, and each of the light absorbers 6, 6 is formed by a reflection optical system. It is provided on the optical path of a certain anamorphic mirror 1. The light absorbers 6, 6 are composed of TFT liquid crystal elements (hereinafter, referred to as liquid crystal light absorbers 6), and the light absorption width of the liquid crystal light absorbers is changed and driven by a liquid crystal driver 7. I have. Specifically, each liquid crystal light absorber 6
Are arranged such that only a selected one of the plurality of segments 6a arranged in parallel with the lens optical axis blocks light transmission.

The aperture adjusting section 8 includes an aperture blade 8a and an actuator 8b for driving the aperture blade 8a.
A signal indicating the amount of light from the subject from the CD signal processing circuit 9 is input, and the aperture of the aperture blade 8a is adjusted so that the diameter of the diaphragm corresponds to the amount of light from the subject.

The liquid crystal driving section 7 inputs a signal indicating the light amount of the object from the CCD signal processing circuit 9 and outputs a signal A (not shown).
The signal is converted into a digital signal by a / D converter. Then, based on the numerical value indicated by the input digital signal,
The number of segments 6a... Corresponding to the numerical value is driven. In addition, a volume for detecting the operation amount of the actuator 8b in the aperture adjustment unit 8 is provided,
By inputting the voltage signal of this volume, the segments 6a ...
May be performed.

As in this embodiment, in a stereoscopic image pickup apparatus having the aperture adjusting section 8 and the aperture diameter of the lens system 2 changing, if the width of the non-reflection area is fixed, the overlap phenomenon or the overlap phenomenon occurs. It becomes difficult to completely eliminate the band-shaped non-light partial phenomenon. However, as in this embodiment,
The liquid crystal light absorber 6 is provided, and the liquid crystal is driven in accordance with the lens aperture diameter (the number of the segments 6a... In the liquid crystal light absorbers 6, 6 which block light transmission is changed).
Thereby, the width of the non-light area can be changed in accordance with the change in the aperture diameter, and the overlap phenomenon or the band-shaped non-light partial phenomenon can be completely eliminated.

In this embodiment, the width of the non-light area is automatically changed. However, the present invention is not limited to this. For example, the user may manually adjust the width while viewing the display surface of the stereoscopic imaging apparatus. Alternatively, a changeover switch for selecting between indoor use and outdoor use may be provided, and the user may perform manual control by himself / herself. Further, the arrangement positions of the liquid crystal light absorptions 6, 6 are not limited to the positions shown in this embodiment, but may be other positions on the optical path, and the second mirrors 3R ₂ , 3L
_It may be provided so as to be attached to the joint end portion of No. ₂ .

(Embodiment 4) In the above embodiment,
The luminous flux portions of the two information beams at positions close to each other are referred to as C
Although a non-reflective area for preventing the light from being guided to the CD 30 is provided, in this embodiment, instead of the non-reflective area, as shown in FIG. 5, these are provided on the joint end side of the second mirrors 3R ₂ and 3L _2. Reflection regions 10 and 10 that are discontinuous with respect to changes in the curved surfaces of the mirrors 3R ₂ and 3L ₂ may be provided. That is, the first embodiment
The type in which the portion at the joint end side of the second mirrors 3R ₂ and 3L ₂ is cut off has the function of allowing the image input from the opening 2R of the right eye component to escape from the opening 2L of the left eye component. Although the light beam portion is not guided to the CCD 30, the reflection regions 10, 10
Is provided, the image input from the opening 2R of the right eye component is allowed to escape again from the opening 2R of the right eye component. With such a configuration, the light beam portion can be prevented from being guided to the CCD 30.

In the above embodiment, a mirror is shown as the reflection optical system, but a prism may be used instead.

[0036]

As described above, according to the present invention, since the non-reflection area or the reflection area for preventing the light flux portions of the right and left information light beams at positions close to each other from being guided to the image pickup device is provided, the overlap area is provided. The phenomenon can be reduced or eliminated. Further, if the non-light area is configured to correspond to the aperture diameter of the lens system, it is possible to completely eliminate the overlap phenomenon or the band-shaped non-light partial phenomenon. Furthermore, since the width of the non-reflection area is configured to be changeable, the effect of completely eliminating the overlap phenomenon or the band-shaped non-light partial phenomenon can be achieved even for a stereoscopic imaging device in which the aperture diameter of the lens changes.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an optical device of a stereoscopic imaging device according to a first embodiment of the present invention.

FIG. 2 shows a non-light area width D _{1 of the} present invention, an aperture diameter D _{2 of a} lens system, and an on-axis light flux diameter D ₃ determined by the aperture diameter D ₂ .
It is explanatory drawing which shows the relationship with.

FIG. 3 is a schematic diagram illustrating an optical device of a stereoscopic imaging device according to a second embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating an optical device of a stereoscopic imaging device according to a third embodiment of the present invention.

FIG. 5 is a schematic diagram illustrating an optical device of a stereoscopic imaging device according to a fourth embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an overlap phenomenon.

FIG. 7 is an explanatory diagram showing a cause of occurrence of an overlap phenomenon.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 anamorphic mirror (reflection optical system) 2 lens system 2R opening 2L opening 3R ₁ first mirror 3L ₁ first mirror 3R ₂ second mirror 3L ₂ second mirror 4 flat surface 5 light absorber 6 liquid crystal light absorber 7 Liquid crystal drive unit 8 Aperture adjustment unit 8 9 CCD signal processing circuit 30 CCD

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-154663 (JP, A) JP-A-7-152096 (JP, A) JP-A-2-301740 (JP, A) JP-A-50- 23633 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G03B 35/10 G02B 13/08 H04N 13/02

Claims (3)

(57) [Claims] An information light for the right eye and an information light for the left eye are respectively taken in from two openings provided at positions spaced apart from each other by a predetermined distance in the horizontal direction, and the respective information lights are approached by a reflection optical system having a reflection surface. An optical device of a three-dimensional imaging device configured to form both information beams having passed through the reflection optical system into different left and right regions on a single image sensor by a lens system, wherein the two information beams are located close to each other; A liquid crystal element provided on a reflection surface of the reflection optical system or on an optical path in the reflection optical system so as to form a non-reflection area for preventing a light beam portion from being guided to the image pickup device, and a liquid crystal driving the liquid crystal element An optical device for a three-dimensional image pickup device, comprising: a driving unit; and wherein a width of a non-reflection area by the liquid crystal element can be changed. 2. The apparatus according to claim 1, further comprising means for detecting a stop diameter of the lens system, wherein a width of a non-reflection area by the liquid crystal element can be changed according to the stop diameter.
An optical device of the three-dimensional imaging device according to 1. 3. The stereoscopic imaging apparatus according to claim 1, further comprising means for detecting a subject illuminance, wherein a width of a non-reflection area by the liquid crystal element can be changed according to the subject illuminance. Optical device.