JPH05328366A - High resolution still image capture device - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain high-resolution still images with a simple configuration. When a horizontally wide screen image pickup device 20 is used for picking up a still image, a green signal is output from a divided image pickup region 20A of the first half of the image pickup device 20 which is divided in the horizontal direction, and the remaining half of the image pickup device is divided. A red signal and a blue signal are output from the imaging area 20B. Image sensor 2
Since 0 is for a wide wide screen having a large number of pixels, even if this is divided into two and used, each divided imaging area 2
The number of pixels of 0A and 20B does not decrease,
A high-resolution still image can be obtained because the number of pixels is equal to or larger than that of a single image sensor used when a normal aspect ratio (4: 3) is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a high-resolution still image pickup device suitable for application to electronic still cameras and the like, and is capable of obtaining a high-resolution still image by using a horizontally wide image pickup device. It was made possible.

[0002]

2. Description of the Related Art There is known an electronic still camera capable of picking up a subject image for each frame and recording the image pickup signal on a magnetic recording medium such as a disk-shaped magnetic disk or a magnetic sheet.

In this kind of electronic still camera as well, there is a trend toward higher resolution in recent years, and as a countermeasure therefor, a two-plate type image pickup device using two image pickup elements or an image pickup element instead of using one image pickup element is used. An image pickup device in which a color filter attached to the front surface of the device is devised is considered.

[0004]

Since the two-plate type image pickup device needs to have two image pickup systems, the scale of the device is increased accordingly, and when applied to an electronic still camera, the price, weight or size is increased. There is a problem in terms of.

[0007] In the device that devises the color filter, since only one image pickup device is used after all, there is a limit to the improvement in resolution.

Therefore, the present invention solves such a conventional problem, and proposes a high-resolution still image pickup device capable of obtaining a desired high resolution without increasing the circuit scale. ..

[0007]

In order to solve the above problems, in the first invention, when the horizontally wide screen image pickup device is used for picking up a still image, the image pickup device is divided into two parts in the horizontal direction. The green signal is output from the divided image pickup area in the first half, and the red signal and the blue signal are output from the divided image pickup area in the remaining second half.

In the second aspect of the invention, the subject image is color-separated into a green light component and other light components by using a dichroic mirror, and each color-separated image corresponds to the first half of the horizontally wide screen image pickup device. It is characterized in that images are formed in the divided image pickup area and the divided image pickup area in the latter half.

[0009]

As shown in FIG. 2, as the image pickup device 20, an image pickup device used for so-called horizontal wide screen is used. For example, a horizontally long image sensor is used that can image a wide screen having an aspect ratio of 16: 9, which is the same as the screen ratio for high definition. In the wide-screen image pickup device 20, for example, when the horizontal direction H is composed of 2000 pixels and the vertical direction V is composed of 1000 pixels, even if it is divided into two in the horizontal direction, it becomes 1000 × 1000 pixels. Since the resolution is sufficient to capture images, and two images are used to compose one still image,
Higher resolution still images can be obtained.

Therefore, the image pickup device 20 is divided into two in the horizontal direction, red and blue color separation images are formed in the divided image pickup area 20A in the first half (left half), and the divided image pickup in the latter half (right half). An optical system up to the image pickup device 20 is configured so that a green color separation image is formed in the region 20B (see FIG. 1).
reference). The color-separated images formed on the image sensor 1 are continuously read out as usual.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a case where an example of a high-resolution still image pickup device according to the present invention is applied to the electronic still camera described above will be described in detail with reference to the drawings.

As the image pickup device used in the present invention, an image pickup device used for reproducing a horizontally wide screen is used instead of a normal aspect ratio (4: 3). This horizontal wide screen is a screen used for high-definition images such as high-vision, and the aspect ratio of the image sensor used when displaying such a horizontal wide screen is usually 16 as shown in FIG. : 9
Is.

In the present invention, the image pickup device 20 used for such a wide screen is used by dividing it into two in the horizontal scanning direction (horizontal direction). That is, different color separation images are projected on the first half (left half) and the second half (right half) of the divided image pickup areas 20A and 20B, which are divided into two in the horizontal direction.

In this example, the color separation images of the red component and the blue component of the subject image are projected on the first half divided image pickup area 20A,
A color-separated image of a green component (or a luminance component) is projected on the latter half of the divided imaging region 20B.

The resolution of such an image pickup device 20 has been increased in recent years, and recently, as shown in FIG.
An imaging device configured by arranging 0 pixels and about 1000 pixels in the vertical direction is also considered, in which case a total of 20
It becomes an image sensor of 0,000 pixels.

Therefore, even if the image pickup devices 20 are used by half, the number of pixels of the image pickup device 20 alone is sufficient for the electronic still camera. Since two still images are used to form a still image, a high resolution still image can be obtained.

The image pickup device 20 shown in FIG. 3 does not have a wide aspect ratio in a strict sense, but since it can be reorganized into an image pickup signal having a predetermined aspect ratio by signal processing, there is no particular problem.

An optical system for realizing the above-mentioned basic concept is shown in FIG.
Shown in. In the figure, a subject image 11 is guided to a dichroic mirror 12 via an optical lens system (not shown), and in this example, a color separated image R / R having red and blue color components.
B and a color separated image G having a green color component, and the red and blue color separated images R / B are a pair of reflection mirrors 13 and 14.
After that, the image is projected and imaged on the image pickup element, for example, the first half divided image pickup area 20A of the CCD 20.

Similarly, the green color-separated image G is also projected and imaged through the pair of reflecting mirrors 16 and 17 onto the second half divided image pickup area 20B of the CCD 20.

The divided image pickup area 2 is so arranged that only the red and blue color separated images R / B are projected on the divided image pickup area 20A in the first half.
On the surface of 0A, for example, a color filter 30 as shown in FIG. 4 is used so as to form an image in a checkered color separation image.

Since only the green color separated image G is separated on the mirror 16 side by the dichroic mirror 12, a color filter is not particularly required on the latter half of the divided image pickup area 20B, but for example, the whole green component as shown in FIG. Transparent color filter 3
You can also add 1.

By arranging the color filters 30 and 31 as described above, when the CCD 20 is continuously scanned in the horizontal direction as usual, an image pickup signal is obtained in a kind of compressed form as shown in FIG. can get. The first half of the horizontal period is the red and blue image pickup signals, and the second half is the green image pickup signal.

Here, only the red and blue color separated images R / B of the subject image 11 are formed in the first half divided image pickup area 20A, and the green color separated image G is taken in the latter half split image with the same positional relationship. In order to form an image in the area 20B, it is necessary to select the relationship among the mirrors 13, 14, 16, 17 as shown in FIG. And mirror 1 in such a relationship
Even when 3, 14, 16, and 17 are arranged, some gap W is generated between the divided imaging regions 20A and 20B.

As a result, even when the CCD 20 is normally scanned to output the image pickup signal, a no-signal section corresponding to the gap W is generated as shown in FIG. 6, but the red and blue image pickup signals and the green image signal are generated. Since there is a case where signal processing is performed such that the time axis of the image pickup signal is doubled so as to have a length of one horizontal period, this non-signal section is not a particular problem.

FIG. 7 shows an electronic still camera 10 as a high-resolution still image pickup device adopting the above-mentioned scanning method.
The signal processing system of the main part of is shown. In the figure, the subject image 1
1 is imaged on the CCD 20 through the iris 41 and the optical lens system 42 (including the optical system shown in FIG. 1), and the image pickup signals (for convenience, R / B and G) are A / D
After the conversion processing, the γ correction circuit 44 performs correction processing so that the γ characteristic of the display system (for example, CRT) becomes a linear characteristic.

After that, it is supplied to the frame memory 45 and stored for one frame, and after various signal processing such as crystal defect correction, aperture correction, shading correction, etc. is performed in the signal processing circuit 46, a disk-shaped magnetic disk or It is recorded on the magnetic recording medium 50 such as a magnetic sheet. Reference numeral 47 is a controller for controlling writing and reading of an image pickup signal (image pickup data). The reproduced image pickup data is converted to an analog signal by the D / A converter 51 and then led to the output terminal 52.

As is apparent from FIG. 3, since the number of green pixels is twice the number of red and blue pixels, there is a relationship of G: B: R = 4: 2: 2, which is the so-called D1 type digital. Since the image pickup signal can be easily obtained, the image pickup data may be directly led to the output terminal 52 without passing through the D / A converter 51.

In the case of FIG. 7, the image pickup signal form recorded on the magnetic recording medium 50 remains the original signal form as shown in FIG. 6, but the time axis of the image pickup signal is doubled to obtain two systems of signals. The data can be recorded as it is, or can be recorded after being converted into the form of a television signal of, for example, the NTSC system after the time axis expansion processing. For example, in the case of changing to the form of an NTSC television signal and storing it, if the reproduced image pickup signal is directly supplied to an existing television receiver, it can be reproduced, which is very convenient. As a result, a high-resolution still image can be reproduced.

Although the configuration is slightly complicated, it may be possible to externally select the signal format for recording.

FIG. 8 shows another example of the optical system shown in FIG.
In the example of FIG. 8, a birefringent plate 60 composed of a crystal plate or the like is used in place of the dichroic mirror, and the light incident on the birefringent plate 60 selected to have a predetermined thickness is normal light (straight) and predetermined light. It is divided into extraordinary light (refracted light) refracted at a distance d, and the divided imaging areas 20 correspond to each other.
A projection image is formed on A and 20B.

As described above, when the birefringent plate 60 is used, it is not necessary to use a mirror or the like, so that the structure of the optical system can be simplified accordingly. A prism may be used as the optical system.

As an example of divisional use of the CCD 20, the color separation image may be projected and imaged on the respective divided image pickup areas 20C and 20D by dividing the CCD 20 into two in the vertical direction as shown in FIG. .. A luminance signal may be used instead of the green signal.

Instead of the primary color filter as the color filter,
It may be a complementary color filter or a combination of primary color filters and complementary color filters. The signal corresponding to the filter used is CC
It will be obtained from D20.

[0034]

As described above, in the high-resolution still image pickup device according to the present invention, the horizontally wide screen image pickup device is used, and the image pickup device is divided into two and used as the still image pickup device. is there.

According to this, the number of pixels of each divided image pickup area is comparable to the number of pixels of the image pickup device when obtaining an image having a conventional aspect ratio, and the same subject image having different colors is divided. Since the image is projected and imaged in the imaging region, a very high resolution imaging signal for a still image can be easily obtained without increasing the circuit scale.

Therefore, the present invention is extremely suitable when applied to an image pickup apparatus such as an electronic still camera which aims to achieve higher resolution as described above.

[Brief description of drawings]

FIG. 1 is a diagram of a main part showing an example when a high-resolution still image pickup device according to the present invention is applied to an electronic still camera.

FIG. 2 is a diagram showing an aspect ratio for a wide screen.

FIG. 3 is a diagram showing an aspect ratio for a wide screen.

FIG. 4 is a diagram of a color filter.

FIG. 5 is a diagram of a color filter.

FIG. 6 is a diagram of an image pickup signal obtained by division projection.

FIG. 7 is a system diagram of an electronic still camera to which the present invention has been applied.

FIG. 8 is a diagram showing another example of an optical system.

FIG. 9 is a diagram showing another example of divided use of the image sensor.

[Explanation of symbols]

 10 Imaging Device (Electronic Still Camera) 11 Subject Image 12 Dichroic Mirror 13, 14, 16, 17 Mirror 20 Imaging Device 20A, 20B Divided Imaging Area 50 Magnetic Recording Medium 60 Birefringent Plate

[Procedure amendment]

[Submission date] September 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

In order to solve the above problems, in the first invention, when the horizontally wide screen image pickup device is used for picking up a still image, the image pickup device is divided into two parts in the horizontal direction. The green signal is output from one of the divided image pickup areas, and the red signal and the blue signal are output from the other divided image pickup area.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction content]

In the second invention, the subject image is color-separated into a green light component and other light components by using a dichroic mirror, and each color-separated image corresponds to one of the horizontally wide wide-screen image pickup devices. It is characterized in that images are formed in the divided image pickup area and the other divided image pickup area, respectively.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Therefore, the image pickup device 20 is divided into two in the horizontal direction, red and blue color separation images are formed in the divided image pickup area 20A in the first half (left half), and the divided image pickup in the latter half (right half). An optical system up to the image pickup device 20 is configured so that a green color separation image is formed in the region 20B (see FIG. 1).
reference). The color-separated images formed on the image sensor 20 are continuously read out as usual.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiharu Kobayashi 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (4)

[Claims] 1. When a horizontally wide image pickup device is used for still image pickup, a green signal is output from a divided image pickup region of the first half of the image pickup device divided into two in the horizontal direction, and a divided image pickup of the remaining latter half is performed. A high-resolution still image capturing device characterized in that a red signal and a blue signal are outputted from a region. 2. The high-resolution still image pickup device according to claim 1, wherein a luminance signal is output instead of the green signal output from the first half divided image pickup area. 3. A subject image is color-separated into a green light component and other light components by using a dichroic mirror, and each color-separated image corresponds to the first half divided image area and the second half of the corresponding horizontally wide screen image pickup element. A high-resolution still image pickup device, which is configured to form an image in each of the divided image pickup regions. 4. The high resolution still image pickup device according to claim 3, wherein a birefringent plate is used in place of the dichroic mirror.