JP2000295635A - Three-dimensional image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a three-dimensional image pickup device by which image signals of a plurality of images with sufficient parallax can be obtained without the need for a separation circuit in spite of a comparatively simple configuration and a small size. SOLUTION: In this three-dimensional image pickup device, a stereo optical system 1 forms a plurality of object images with parallax and by photographing the same object at different view points apart from each other to a plurality of image pickup elements 2L, 2R that are mounted closely to each other on one semiconductor substrate, and image processing circuits 10L, 10R having the identical characteristic provided corresponding to the image pickup elements 2L, 2R process separately output signals from the image pickup elements 2L, 2R respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a three-dimensional imaging device,
In particular, the present invention relates to a three-dimensional imaging apparatus capable of obtaining a three-dimensional image (stereoscopic image) by capturing a plurality of images having parallax for the same subject, or measuring a distance (ranging) to the subject.

[0002]

2. Description of the Related Art In order to capture a three-dimensional image, it is necessary to capture a plurality of images of the same subject viewed from a plurality of different places separated from each other, that is, images having parallax. Therefore, in the related art, two cameras are generally provided in one three-dimensional imaging device, and two subject images captured from two different places are captured by different cameras.

FIG. 2 is a circuit block diagram showing a schematic configuration of such a three-dimensional image pickup apparatus. In FIG. 2, 1L denotes an image pickup optical system of a left-eye camera, 1R denotes an image pickup optical system of a right-eye camera, The two imaging optical systems 1L and 1R form two left and right object images having parallax obtained by taking the same object from different viewpoints that are appropriately separated from each other on the respective solid-state imaging devices 2L and 2R. That is, the left subject image is formed on the solid-state imaging device 2L, and the right subject image is formed on the solid-state imaging device 2R.

Reference numerals 3L and 3R denote timing generators for generating clock pulses for driving the solid-state imaging devices 2L and 2R.
L and 4R receive outputs from the timing generators 3R and 3L, and drive the solid-state imaging devices 2L and 2R (imager driving drivers). 5L and 5R remove noise components from the output signals of the solid-state imaging devices 2L and 2R. CDS to do
(Correlated double sampling circuit) circuit, 6L and 6R are AG
C (auto gain control) circuits, 7L and 7R are analog signals, A / D conversion circuits for converting output signals of AGC circuits 6L and 6R into digital signals, 8L and 8R
Is a microcomputer that processes output signals of the A / D conversion circuits 7L and 7R, and performs AWB (auto white balance) processing, AE (automatic light control) processing, and the like. 9L,
9R is an image signal output circuit for outputting image signals from the microcomputers 8L and 8R.

As described above, the conventional apparatus has a configuration in which two optical systems, two image pickup means, and two image processing circuits are provided.

By the way, a three-dimensional image pickup apparatus that takes a three-dimensional image by using two cameras is large in size because two cameras are used. There was a problem that was difficult.

Further, in order to constitute a three-dimensional image pickup apparatus with a plurality of camera units, it is necessary to align the optical axes between two cameras, but there is also a problem that the optical axis alignment between different cameras is considerably difficult. Was.

Further, when a plurality of cameras are provided, it is necessary to externally synchronize the cameras in processing the image signal, which naturally requires a circuit for synchronizing. This causes high cost of the three-dimensional imaging device.

Therefore, there is provided a three-dimensional image pickup apparatus which has a relatively simple configuration using a single image pickup means and is capable of obtaining images of a plurality of subject images having a sufficient parallax with respect to the same subject while being small in size. It has been developed. FIG. 3 is a schematic configuration diagram illustrating an optical system and an image sensor of an example of such a three-dimensional image capturing apparatus.

In FIG. 3, reference numeral 2 denotes a solid-state image sensor, and 2L denotes an area forming one half of the image pickup area of the solid-state image sensor 2.
R is an area that forms the other half of the imaging area. 12
Is a cover glass for the solid-state imaging device provided on the front side of the solid-state imaging device 2, and is disposed in front of and in parallel with the imaging region of the solid-state imaging device 2.

Reference numerals 13L and 13R denote imaging lenses provided corresponding to the respective areas 2L and 2R of the solid-state imaging device 2 through the cover glass 12, and 14L and 14R denote the imaging lenses 13
Diaphragms disposed in front of L, 13R, 15
L, 15R are image sensor-side mirrors provided in front of the apertures 14L, 14R so as to face obliquely outward corresponding to the areas 2L, 2R of the solid-state image sensor 2, 16L, 16R.
Is a subject-side mirror provided outside the image sensor-side mirrors 15L and 15R so as to face obliquely inward corresponding to the mirrors. 18L and 18R are infrared cut filters, 1
9L and 19R are light beam limiting plates.

The pair of subject-side mirrors 16L and 16R reflect light from the same subject at different positions to the pair of image pickup-side mirrors 15L and 15R. The pair of image sensor-side mirrors 15L, 15R are paired with the pair of subject-side mirrors 16L, 1L.
The light from the subject reflected by the 6R is reflected toward each half 2L, 2R of the imaging area of the solid-state imaging device 2. Then, a pair of mirrors 15L, 15
A pair of lights from the subject reflected by the R are stopped down by the stops 14L and 14R, and are formed by the imaging lenses 13a and 13a.
3b forms an image on different areas 2L and 2R of the solid-state imaging device 2. In addition, the light that forms the subject image is cut off the infrared rays by passing through the infrared cut filters 18a and 18b.

According to such a three-dimensional image pickup apparatus, one subject is composed of one stereo unit composed of the object side reflection means 16L and 16R, the image pickup element side reflection means 15L and 15R, the lenses 13L and 13R, and the apertures 14L and 14R. Since different areas 2L and 2R of one solid-state imaging device 2 are imaged with different parallaxes by the optical system, the number of imaging devices 2 required for the three-dimensional imaging device is one. In addition, if the optical axis alignment is performed for each optical system with respect to the same image sensor 2, the necessary optical axis alignment is completed, so that the optical axis alignment is easier than in the case where the optical axis alignment is performed between two cameras. Become.

Since a pair of subject-side reflecting means 16L and 16R for obtaining two images having parallax are provided outside the pair of image-capturing-element-side reflecting means 15L and 15R, the size of the three-dimensional image pickup apparatus is reduced. The parallax can be relatively increased by increasing the distance between the object-side reflecting means 16L and 16R. Therefore, a more three-dimensional three-dimensional image can be obtained with high accuracy.

Further, since the light beam that has been stopped by the pair of stops 14L and 14R is imaged on the two areas 2L and 2R of the image pickup device 2 by the pair of image forming lenses 13L and 13R, it is unnecessarily large as an image forming lens. It is not necessary to use such a device, and it is possible to obtain a three-dimensional imaging device having excellent optical characteristics for a small size. In these respects, it can be said that the conventional three-dimensional imaging apparatus shown in FIG. 3 is excellent.

[0016]

In the conventional three-dimensional image pickup apparatus shown in FIG. 3 described above, a plurality of subject images having parallax are formed in a plurality of adjacent areas 2L in the image pickup area of one image pickup device 2. , 2R, two subject images are captured as one image. To create a stereoscopic image or perform distance measurement, the output of the one image sensor 2 is processed from the output of an image signal processing circuit that performs image processing. There is a problem that a separation circuit for separating and taking out signals of two subject images is required.

The separation circuit has, for example, a memory for storing a left half image signal in each horizontal scan and a memory for similarly storing a right half image signal, and two image signals respectively taken out of each memory. Are processed as signals of different subject images having parallax with each other,
In this example, a control circuit for distributing signals to different memories in the first half and the second half in each horizontal cycle is also required. Therefore, the control circuit becomes a rather complicated circuit.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and requires a separation circuit for separating image signals of a plurality of images having a sufficient parallax with a relatively simple configuration and a small size. It is an object of the present invention to provide a three-dimensional imaging device which can be obtained without any problem.

[0019]

According to a first aspect of the present invention, there is provided a three-dimensional image pickup apparatus comprising: It has a stereo optical system that forms a plurality of subject images with parallax captured from different viewpoints that are separated from each other and an image signal processing circuit that has the same characteristics and is provided corresponding to each of the imaging devices. The signal of the subject image formed on each of the image pickup devices is separately processed by each image signal processing circuit and output.

Therefore, according to the three-dimensional image pickup apparatus of the present invention, a plurality of subject images having parallax by the stereo optical system are transferred to the plurality of image pickup devices having the same characteristics and arranged close to one semiconductor substrate. An image is formed, and output signals of the plurality of image sensors are separately processed by respective image signal processing circuits provided corresponding to the image sensors to obtain a plurality of subject image signals. There is no need for a separation circuit for separating two subject image signals from the output signal of a single image sensor.

Since the plurality of image sensors are formed on one semiconductor substrate so as to have the same characteristics, signals of a plurality of subject images having parallax may be deviated due to differences in the characteristics of the image sensors. Absent. Therefore, an accurate and distortion-free stereoscopic image can be obtained, and accurate distance measurement can be performed.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A three-dimensional image pickup apparatus according to the present invention is basically composed of a semiconductor device having a plurality of image pickup elements having the same characteristics in proximity to one semiconductor substrate and a plurality of image pickup elements. An optical system that forms a plurality of subject images having parallax captured from different viewpoints separated from each other with respect to the same subject; and an image signal processing circuit having the same characteristics provided for each of the image sensors. , And the signals of the subject image formed on the respective image sensors are separately processed and output by the respective image signal processing circuits, and each image sensor may be a CCD type image sensor. And
It may be a MOS-type image sensor or a MOS-type image sensor, regardless of the type. What is important is that a plurality of image sensors are arranged close to one semiconductor substrate,
That is, each image sensor has the same characteristics.

The optical system which captures one subject from different viewpoints and forms an image on different areas of one image sensor is provided, for example, so as to face obliquely outward with respect to two different areas of the image sensor. A pair of imaging element-side reflection means, and a pair of imaging element-side reflection means, which are disposed so as to face diagonally forward to the outside of the pair of imaging element-side reflection means, and mutually reflect light from a subject to the corresponding imaging element-side reflection means. A subject-side reflecting means, and a pair of light sources that are reflected by the pair of subject-side reflecting means, and further form light from the same subject reflected by the pair of imaging element-side reflecting means on two different portions of the imaging region of the image sensor. And a pair of diaphragms provided between each of the imaging element-side reflecting means and the above-described lens, and this is disclosed in Japanese Patent Application No. 10-33870. It is being proposed by the issue. Of course, as long as a plurality of subject images having parallax can be formed on different areas of one image sensor, any optical system may be used.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 is a circuit diagram showing a schematic configuration of a first embodiment of the three-dimensional imaging apparatus of the present invention.

In the drawing, reference numeral 1 denotes the same subject captured from different viewpoints having parallax, and two left and right subject images obtained thereby are formed on separate image sensors 2L, 2R formed on one semiconductor device 2. 3 shows a stereo optical system. Since this stereo optical system is not different from the conventional case shown in FIG. 3, its configuration and operation will not be described. The optical system 1 forms the left subject image on the image sensor 2L and the right subject image on the image sensor 2R. Image sensor 2L and image sensor 2R
Are formed at the same time in the vicinity of one semiconductor substrate so as to have the same characteristics as one semiconductor device.

Reference numeral 3 denotes a timing generator for generating a driving clock pulse for driving the solid-state imaging device 2L, 4L,
4R receives the output from the timing generator 3 and drives the image pickup devices 2L and 2R (imager drive drivers). 5L and 5R remove CDS (correlation noise) from the output signals of the solid-state image pickup devices 2L and 2R. Double sampling circuits) circuits, 6L and 6R are AGC (auto gain control) circuits, 7L and 7R are analog signals, A / D conversion circuits for converting output signals of the AGC circuits 6L and 6R into digital signals, 8L and 8R Is a microcomputer for processing output signals of the A / D conversion circuits 7L and 7R, and includes AWB (auto white balance) processing, AE
(Automatic light amount control) processing and the like are performed. 9L and 9R are image signal output circuits for outputting image signals from the microcomputer 8. The timing generator 3 and the circuit 5L ~
9L constitutes an image signal processing circuit 10L for the left subject image, and includes the timing generator 3 and the circuits 5R to 5R.
The image signal processing circuit 10R for the right object image is constituted by R.

As described above, this three-dimensional image pickup apparatus differs from the conventional one shown in FIG. 3 in that the two image pickup devices 2L and 2R are formed adjacent to one semiconductor substrate. Image signal processing circuits are provided one by one (10L, 10R) corresponding to the elements 2L, 2R, and two subject images with parallax formed on the two image sensors 2L, 2R are imaged by the image sensors 2L, 2R. And each image sensor 2L,
Each image signal output from 2R is converted into its respective image sensor 2L,
Each image signal processing circuit 10L provided corresponding to 2R,
Since the image signals of two subject images having parallax are obtained by processing using 10R, a separation circuit that separates two subject image signals from the output signal of one image sensor as in the conventional example shown in FIG. do not need.

Since the plurality of image sensors are formed on one semiconductor substrate so as to have the same characteristics, signals of a plurality of subject images having parallax may be distorted due to differences in the characteristics of the image sensors. Absent. Therefore, an accurate and distortion-free stereoscopic image can be obtained, and accurate distance measurement can be performed.

[0029]

According to the three-dimensional image pickup apparatus of the present invention, a plurality of subject images having parallax by the stereo optical system are transferred to a plurality of image pickup devices having the same characteristics and arranged close to one semiconductor substrate. An image is formed, and output signals of the plurality of image sensors are separately processed by respective image signal processing circuits provided corresponding to the image sensors to obtain a plurality of subject image signals. There is no need for a separation circuit for separating two subject image signals from the output signal of a single image sensor.

Since the plurality of image sensors are formed on one semiconductor substrate so as to have the same characteristics, signals of a plurality of subject images having parallax may be distorted due to differences in the characteristics of the image sensors. Absent. Therefore, an accurate and distortion-free stereoscopic image can be obtained, and accurate distance measurement can be performed.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram illustrating a schematic configuration of one embodiment of a three-dimensional imaging apparatus according to the present invention.

FIG. 2 is a circuit block diagram showing a schematic configuration of a conventional example.

FIG. 3 is a schematic configuration diagram illustrating a configuration example of an optical system of the three-dimensional imaging device.

[Explanation of symbols]

2 ... Semiconductor device, 2L, 2R ... Image sensor, 10
L, 10R: image signal processing circuit.

Continued on the front page F term (reference) 2H011 AA06 BA05 BB01 2H051 AA00 BB07 CA09 CA12 CB11 CB27 CB29 2H059 AA08 AA18 4M118 AA10 AB01 AB03 BA06 BA30 5C061 AA25 AB04 AB06 AB08

Claims (1)

[Claims] 1. A semiconductor device comprising a plurality of image pickup elements having characteristics identical to each other provided in proximity to one semiconductor substrate; and a parallax image obtained by imaging the same subject from different viewpoints separated from each other on the plurality of image pickup elements. A stereo optical system that forms a plurality of subject images with the same, and an image signal processing circuit that has the same characteristics as each other and that is provided corresponding to each of the imaging devices, and is formed on each of the imaging devices. A three-dimensional imaging apparatus characterized in that a signal of a subject image is processed and output separately by each image signal processing circuit.