JPH06121326A - Two-board type ccd camera - Google Patents

Abstract

PURPOSE:To suppress the increase of a cost due to the operation of turning both an Y-CCD 3a and a C-CCD 4a into a CCD of the large number of picture elements to obtain picture data of a high resolution. CONSTITUTION:The CCD of the large number of picture elements is used for an Y-CCD 3a to which a high resolution is requested, and the CCD of the small number of picture elements is used for a C-CCD 4a to which only a low resolution is required, from the visual characteristic of a human body. At the time of operating a picture synthesis by a picture synthesizing circuit 12, data are interpolated by a picture element conversion circuit 14 since the number of picture data from the C-CCD 4 is smaller than the number of picture data from the Y-CCD 3a, and the picture synthesis is operated after the number of both the picture data is matched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-plate CCD camera, and more particularly to two types of CCD image pickup devices (hereinafter, simply referred to as "CC").
2 plate type C for high resolution effectively combining
Regarding CD cameras.

[0002]

2. Description of the Related Art In recent years, as an electronic color camera, an individual type color camera using an individual image pickup device has been widely used in place of the conventional image pickup tube type. Since the image sensor has high sensitivity, CCD
(Charged Coupled Device) is mainly used.

Among the individual type color cameras using the above CCD image pickup device, the outline of a two-plate type CCD camera related to the present invention will be described.

FIG. 5 is a perspective view showing an example of the configuration of a conventional two-plate CCD camera, in which the first CCD 3 is arranged on the optical axis P of the optical lens system 1 and is arranged in a direction orthogonal to the optical axis P. , The second CCD 4 and the total reflection mirror 7 serving as the light receiving portion of the optical finder 6 are arranged to face each other. Further, the half mirror 2 is arranged on the optical axis P so as to be rotatable about the rotation axis 5 in the directions of arrows a and b.

FIG. 6 shows a schematic side view of a two-plate CCD camera. When the optical finder is used, the half mirror 2 is rotated to the position of the solid line in FIG. The incident light from 1 is reflected by the half mirror 2, and the total reflection mirror 7 passes through the focus screen 8.
Then, the light is totally reflected by and is irradiated onto the optical finder 6.

At the time of photographing, the half mirror 2 is rotated in the direction of arrow a to the position shown by the broken line in FIG. Then, the incident light from the optical lens system 1 is dispersed by the transmission and reflection of the half mirror 2, and the first CCD and the second C
Connect the images on the CD.

The first CCD 3 is used as a CCD of a luminance signal system (hereinafter, "luminance signal" is also simply referred to as "Y signal"), and the second CCD 4 is a color signal system (hereinafter, "color"). Signal "is also simply referred to as" C signal ") CCD
Used as.

[0008]

As described above,
In the two-panel camera, the CCD 3 of the Y signal system and the C of the C signal system
An image signal is obtained by using two CCDs of CD4.
The same CCD is usually used for the CCD.

Recently, however, the demand for image quality has increased, and a high-resolution two-chip CCD camera has been required. Therefore, the CCD 3 of the Y signal system and the CCD 4 of the C signal system are connected to a CCD having a large number of pixels (for example, the number of pixels is 100).
0 × 1300 (V × H) or so).

However, in this case, two expensive CCDs having a large number of pixels are used, which significantly increases the cost. Further, as the CCD for the Y signal system, it is necessary to develop two types of a monochrome CCD corresponding to a large number of pixels and a CCD including a stripe color filter and a large number of pixels, which is also a problem.

The present invention has been made in view of the above problems, and is a low-cost, high-resolution image pickup device that suppresses the cost of the CCD.
An object is to provide a plate type CCD camera.

[0012]

A two-plate type C according to claim 1
The CD camera is a CC with a large number of pixels as the first CCD.
D3a and C with a normal small number of pixels as the second CCD
The feature is that the CD4a is used properly.

In the two-plate CCD camera according to the second aspect, the CCD 3a having a large number of pixels as the first CCD is used as a Y signal system, and the ordinary CCD 4 having a small number of pixels as the second CCD.
It is characterized in that a is used for the C signal system.

In the two-chip CCD camera according to the third aspect, the CCD 3a having a large number of pixels as the first CCD is green (G).
In the signal system, a normal small number of pixels C as the second CCD
It is characterized in that the CD4a is used for a red-blue (RB) signal system.

According to a fourth aspect of the present invention, in the two-plate CCD camera, image conversion is performed in which the number of image data obtained from the CCD 4a having a small number of pixels is made equal to the number of image data obtained from the CCD 3a having a large number of pixels by data interpolation. Pixel conversion circuit 14 as means, pixel-converted image data and CCD 3
The image synthesizing circuit 12 is provided as an image synthesizing unit for synthesizing the image data obtained from a.

According to a fifth aspect of the present invention, a two-plate CCD camera is characterized in that a pixel converting circuit 14 as a pixel converting means and an image synthesizing circuit 12 as an image synthesizing means are provided in the camera body.

According to a sixth aspect of the present invention, a two-chip CCD camera is characterized in that a pixel converting circuit 14 as a pixel converting means and an image synthesizing circuit 12 as an image synthesizing means are provided outside the camera body.

[0018]

In the two-plate CCD camera having the structure described in claim 1, as means for realizing the high-resolution two-plate CCD camera, CCDs having a large number of pixels are not used as both CCDs 3a and 4a, but the respective CCDs are used. The number of pixels sufficient to satisfy the required function is selected and used. For example, if the CCD 3a is a multi-pixel CCD (pixel number: 1000 ×
1300) and the CCD 4a is a normal CCD with a small number of pixels.
(Number of pixels: 480 × 768).

With such a structure, only one expensive multi-pixel CCD 3a needs to be used and a high resolution two-plate CCD camera can be realized at a relatively low cost.

In the two-plate CCD camera having the structure described in claim 2, the Y signal CCD 3a is a multi-pixel CCD and the C signal CCD 4a is a normal small pixel CCD.

The human visual sense has a high resolving power for lightness, but has a low resolving power for color. Therefore, the high-resolution CCD 3a can be used for the luminance signal system, and the low-resolution CCD 4a can be used for the color signal system.

With such a structure, only one expensive multi-pixel CCD 3a needs to be used, and a high resolution two-plate CCD camera can be realized relatively inexpensively.

In the two-plate CCD camera having the structure described in claim 3, the multi-pixel CCD 3a is replaced by a green (G) signal system C.
The CD is used as a CD, and the normal CCD 4a having a small number of pixels is used as a CCD for a red-blue (RB) signal system. (In this specification, green may be simply referred to as “G”, red may be simply referred to as “R”, and blue may be simply referred to as “B”.)

With such a structure, only one expensive multi-pixel CCD 3a needs to be used, and a high resolution two-plate CCD camera can be realized relatively inexpensively.

In the two-plate CCD camera having the structure described in claim 4, 1000 × 1300 (V × H) image data per image can be obtained from the CCD 3a of the Y signal system. However, since the RGB stripe filter 9 is used from the CCD 4a of the C signal system, only 480 × 256 (V × H) image data per image can be obtained for each of the RGB color signals. Therefore, it is not possible to use the image data of the Y signal system and the image data of the RB signal system as they are to perform image composition.

Therefore, the pixel conversion circuit 14 performs data interpolation for each of the RB signals having a small number of image data to match the number of image data of the RB signal system and the Y signal system. Then, the image synthesizing circuit 12 performs image synthesizing with the image data of the Y signal system and the interpolated image data of the RB signal system.

With such a structure, only one expensive multi-pixel CCD 3a needs to be used and a high resolution two-plate CCD camera can be realized at a relatively low cost.

A two-plate CCD camera having the structure described in claim 5 is one in which the pixel conversion circuit 14 and the image synthesizing circuit 12 are installed in the camera body, and a two-plate CCD camera having the structure described in claim 6 is The pixel conversion circuit 14 and the image composition circuit 12 are provided outside the camera body.

That is, the pixel converting circuit 14 and the image synthesizing circuit 12 are the parts that perform the final stage of the data processing in the camera, and the locations of these circuits are not limited to those in the camera body. It can be easily installed outside the camera body according to the system configuration needs.

[0030]

1 is a block diagram showing a system configuration of an embodiment of a two-plate type camera of the present invention, which is an embodiment commonly corresponding to the inventions described in claims 1, 2 and 5. In addition,
The parts corresponding to those of the conventional example in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

In FIG. 1, the CCD 3a (first CCD image pickup device) on the optical axis P is a CCD having a large number of pixels used for the Y signal system. C provided in a direction orthogonal to the optical axis P
The CD 4a (second CCD image pickup device) is a normal CCD with a small number of pixels used for the C signal system. Also, C of the C signal system
A vertical RGB stripe filter 9 is provided on the front surface of the CD 4a.

The image connected on the Y signal CCD 3a (hereinafter, "Y signal CCD" is also simply referred to as "Y-CCD") is converted into an electric signal, and the Y readout circuit 3b converts the image data. Is read as. The image data read by the Y read circuit 3b is sent to the frame memory 11 and stored as a Y-CCD output. The image data stored in the frame memory 11 is the image synthesizing circuit 12
Sent to.

The C signal system CCD 4a (hereinafter referred to as "C
The image connected on the "CCD of the signal system" is also simply referred to as "C-CCD" is converted into an electric signal, and the read circuit 4 for C is used.
It is read out as image data by b. The image data read by the C read circuit 4b is sent to and stored in the frame memory 13 as a Y-CCD output.

The image data stored in the frame memory 13 is sent to the pixel conversion circuit (pixel conversion means) 14.
The image conversion circuit 14 performs data interpolation on the image data received from the frame memory 13, and the interpolated image data is sent to the image composition circuit (image composition means) 12.

The image synthesizing circuit 12 includes a frame memory 11
Image data from the pixel conversion circuit 14 is combined with the image data from the pixel conversion circuit 14, and a luminance signal (Y signal) and a color difference signal (Y−
R / Y-B signal).

That is, in the present embodiment, the object to be photographed is divided into an image of the luminance signal system (Y signal system) and an image of the color signal system, and these images are taken, and then they are combined to obtain an image data signal. Here is an example.

In this case, the human visual sense has a high resolution with respect to lightness, but with respect to color, the resolution is low and the color of a small area cannot be identified. is there. Therefore, it is necessary to use a high-resolution CCD for brightness, but a low-resolution CCD for color.

Therefore, in this embodiment, the CCD of the Y signal system is used.
3a is a multi-pixel CCD having the following number of pixels: Y-CCD: number of pixels 1000 × 1300 (V × H:
Vertical x horizontal)

As the CCD 4a of the C signal system, a CCD with a small number of pixels having the following number of pixels is used. C-CCD: Number of pixels 480 × 768 (V × H:
Vertical x horizontal)

The C-CCD 4a has an RG on its front surface.
Since the B stripe filter 9 is provided, RGB
The number of pixels for each color is as follows. R (red) signal system 480 × 256 (V × H) G (green) signal system 480 × 256 (V × H) B (blue) signal system 480 × 256 (V × H)

The image connected on the Y-CCD 3a having the above number of pixels is converted into an electric signal and read out for Y circuit 3b.
Read out as image data by the frame memory 1
It is stored in 1. This frame memory 11 is 1000
Y-CCD with × 1300 storage addresses
1000 × 1300 pieces of image data obtained from 3a are stored as they are.

The image connected on the C-CCD 4a is converted into an electric signal, read by the C read circuit 4b as image data, and stored in the frame memory 13. The frame memory 13 has 480 × 768 storage addresses, and 480 × 768 image data obtained from the Y-CCD 4a is stored as it is.

As described above, since the RGB stripe filter 9 is provided on the front surface of the C-CCD 4a, the frame memory 13 stores 480 × 256 image data for each color of RGB. Become.

The image synthesizing circuit 12 receives the image data of the Y signal system and the image data of the C signal system as input, and outputs the Y signal and Y-R.
It is a circuit that outputs a signal and a Y-B signal.

However, in this case, since the number of Y signal system image data is 1000 × 1300 and the number of R or B signal system image data is 480 × 256, the Y−R signal and The Y-B signal cannot be obtained.

Therefore, in the present embodiment, the pixel conversion circuit 14
Thus, the number of image data of each color of R and B (480 × 256) obtained from the C-CCD 4a having a small number of pixels is interpolated to obtain the number of image data obtained from the Y-CCD 3a having a large number of pixels (1000 × 1300). Process to match.

The configuration of the pixel conversion circuit 14 and the operation of data interpolation will be described below.

FIG. 2 is a block diagram showing the internal structure of the pixel conversion circuit 14 in the embodiment. Interpolation calculation is performed in the following procedure.

(1) The number of pixels of the C-CCD 4a is R, G,
480 x 256 (V x H) for each color of B
And the output frame memory 22 is 1000 × 1300
It has storage addresses of (V × H) pieces of image data. Therefore, for each array address (i, j) {0 ≦ i <1000, 0 ≦ j <1300} of the output frame memory 22, the corresponding frame memory 1 for C-CCD
The image data of 4 neighborhoods in 3 are taken into the pixel interpolation calculation unit 21.

(2) Next, the interpolated value of the image data is calculated using the fetched data in the four neighborhoods, and the result is stored in the output frame memory 22.

(3) The above processing is executed for all array addresses (i, j) to obtain 1000 × 1300 interpolated image data, and the output frame memory 22
To store.

The interpolation calculation method used in this embodiment is linear interpolation, which will be described below.

FIG. 3 is a diagram for explaining an interpolation calculation method in the pixel conversion circuit 14, and Z (0,0), Z
(1,0), Z (0,1), Z (1,1) represent the data in the four neighborhoods, Z (x, y) represents the image data of the interpolation point, and x in (x, y) Represents the distance in the X direction from the point Z (0,0), and y represents the distance in the Y direction. However, Z (0,
0), Z (1,0) and Z (0,0), Z (0,1)
The distance between them is assumed to be "1".

In this case, the image data Z (x,
y) is calculated by the following formula. Z (x, y) = Z (0,0) + {Z (1,0) -Z (0,0)}. X + {Z (0,1) -Z (0,0)}. Y + {Z (1,1) + Z (0,0) -Z (0,1) -Z (0,0)} · x · y where 0 ≦ x <1 0 ≦ y <1

FIG. 4 is a diagram showing a flow chart of the interpolation calculation process, showing the procedure of the interpolation calculation for the R and B image data in the pixel conversion circuit 14 of FIG. The process of this flowchart is performed by the CPU 2 shown in FIG.
3 is mainly executed by the software processing.

The outline of this flowchart will be described below.

(1) In step S401, the array address (i, j) in the output frame memory 22 is initialized (i = 0, j = 0).

(2) In step S402, image data Z (0, 0, 4) in the vicinity of 4 in the frame memory 13 corresponding to the (i, j) pixel in the output frame memory 22.
0), Z (1,0), Z (0,1), and Z (1,1) are obtained.

(3) In step S403, coordinate positions x and y are calculated.

(4) In step S404, Z
(X, y) is calculated and used as image data Z (i, j).

(5) The above arithmetic operation is repeated in the lateral direction (i direction) until i = 1299. (Step S405, Step S406)

(6) In step S407, i
Set to = 0.

(7) The above calculation is repeated in the vertical direction (j direction) until j = 999. (Step S4
08, step S409)

Although each processing in the flowchart shown in FIG. 4 is an example of software processing using the CPU 23, the present invention is not limited to this, and other DSP (digital signal processor) may be used. It may be realized by hardware.

In this way, the pixel conversion circuit 14 interpolates the image data for each color of R and B, and
The image data of 000 × 1300 is stored in the output frame memory 22. (However, the output frame memory 22
Cannot store the image data of each color of R and B at the same time, and store one of them alternately. )

Therefore, in the case of obtaining the Y-R color difference signal, the pixel conversion circuit 14 performs data interpolation of the image data of the R signal system and outputs 100 to the output frame memory 22.
The image synthesizing circuit 12 stores 0 × 1300 image data.
Is 1000 × 13 in the frame memory 11 for the Y signal.
The Y-R signal is generated by using 00 image data and 1000 × 1300 image data of the R signal system stored in the output frame memory 22.

Further, in the case of obtaining the Y-B color difference signal, the pixel conversion circuit 14 performs data interpolation of the image data of the B signal system, and the output frame memory 22 stores 1000
The image synthesizing circuit 12 stores image data of × 1300.
Is 1000 × 13 in the frame memory 11 for the Y signal.
The Y-R signal is generated using the 00 image data and the B signal system 1000 × 1300 image data stored in the output frame memory 22.

As described above, one embodiment of the present invention has been described.
The technical idea of the present invention is not limited to this embodiment, and can be applied to two-plate CCD cameras of various configurations.
Hereinafter, some examples will be described.

(1) For example, as in the invention described in claim 3, the Y-CCD 3a is used as a G signal system and the C-CCD 4a is used as R.
It can be used for the B signal system. The configuration and the like are the same as those of the embodiment shown in FIG. Also, the effect is the same.

(2) Further, as in the invention described in claim 6, the image processing performed by the pixel conversion circuit 14 and the image composition image composition circuit 12 is the final data processing in the camera. The installation location is not limited to the camera body,
It can also be installed outside the camera body depending on the system configuration needs.

(3) In the embodiment shown in FIG. 1, the incident light is split by the half mirror 2 to irradiate the CCDs of the Y signal system and the C signal system, but the method is not particularly limited to this. A method in which incident light is dispersed using a dichroic mirror and a G signal system and RB signal system CCD is irradiated can be easily used.

(4) In the embodiment shown in FIG. 1, C-CC
Although an RGB trio (repeating pattern of RGBRGBRGB) is used for the RGB stripe filter 9 of D4a, the present invention is not particularly limited to this, and a combination of GR, GB, etc. can also be used according to the system configuration needs. .

(5) Y-CCD 3a in the embodiment shown in FIG.
When the pixel size of the C-CCD 4a is similar, there are many advantages in image processing, but it is not necessary that they are similar.
This is because it is merely a problem in arithmetic processing.

(6) Image synthesizing circuit 1 in the embodiment of FIG.
In FIG. 2, Y of the luminance signal and Y-R / Y-B of the color difference signal are output, but the present invention is not particularly limited to this, and the most suitable signal such as Y color difference or RGB may be output depending on the need of the system. Can be output easily.

[0075]

The two-plate type C according to claims 1, 2, 3 and 4
According to the CD camera, a CCD with a large number of pixels is used for a signal system that requires high resolution, and a normal CCD with a small number of pixels is used for a signal system that requires low resolution. A high-resolution two-chip CCD camera can be realized relatively inexpensively.

According to the two-chip CCD camera of the fifth and sixth aspects, since the image processing circuit portion can be installed in any place inside or outside the camera body, the degree of freedom of system configuration is increased. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of an embodiment of a two-plate type camera of the present invention.

FIG. 2 is a block diagram showing an internal configuration of a pixel conversion circuit in the embodiment.

FIG. 3 is a diagram for explaining an interpolation calculation method in the pixel conversion circuit in the embodiment.

FIG. 4 is a diagram showing a flowchart of interpolation calculation processing.

FIG. 5 is a perspective view showing a configuration example of a conventional two-plate CCD camera.

FIG. 6 is a schematic side view of a two-plate CCD camera.

[Explanation of symbols]

 1 Optical Lens System 2 Half Mirror 3a Y Signal System CCD (First CCD Image Sensor) 3b Y Read Circuit 4a C Signal System CCD (Second CCD Image Sensor) 4b C Read Circuit 9 RGB Stripe Filter 11 Frame memory (for Y-CCD) 12 Image composition circuit (image composition means) 13 Frame memory (for C-CCD) 14 Pixel conversion circuit (pixel conversion means) 21 Pixel interpolation calculation unit 22 Output frame memory 23 CPU

Claims (6)

[Claims] 1. A first lens arranged on the optical axis of an optical lens system.
In the two-plate CCD camera, which obtains an image signal using the CCD image pickup device and the second CCD image pickup device arranged in a direction orthogonal to the optical axis, the number of pixels of the first CCD image pickup device and A two-chip CCD camera characterized in that the number of pixels of the two CCD image pickup elements is different. 2. A CCD image pickup device having a large number of pixels of the first CCD image pickup device and a second CCD image pickup device is used as a luminance signal system image pickup device, and a CCD image pickup device having a small number of pixels is used for color signal system image pickup. The two-plate CCD camera according to claim 1, which is an element. 3. A CCD image pickup device having a large number of pixels of the first CCD image pickup device and a second CCD image pickup device is used as a G signal system image pickup device, and a CCD image pickup device having a small number of pixels is taken as an RB signal system image pickup device. The two-plate CCD camera according to claim 1, which is an element. 4. Pixel conversion means for matching the number of image data obtained from a CCD image pickup device having a small number of pixels with the number of image data obtained from a CCD image pickup device having a large number of pixels by interpolation of image data, 3. An image synthesizing means for synthesizing image data obtained by the pixel converting means and image data obtained from a CCD image pickup device having a large number of pixels is used.
Alternatively, the two-plate CCD camera described in 3. 5. A two-plate CCD camera according to claim 4, wherein the pixel converting means and the image synthesizing means are provided in the camera body. 6. A two-plate CCD camera according to claim 4, wherein the pixel converting means and the image synthesizing means are provided outside the camera body.