JP2001218116A - Image pickup device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image pickup device that picks up an object with high resolution and high contrast. SOLUTION: A two-dimensional image pickup element 103 consists of a matrix of 3×3 single image pickup elements. Pin-holes with 1/4 the size of each single image pickup element 103 are arranged to a two-dimensional pin hole filter 102 at the same interval as that of the single image pickup elements. By moving the two-dimensional image pickup element 103 of a half of the longitudinal and lateral sizes of the single image pickup element, the incident light passing through each pin-hole is allowed to reach an upper left position, an upper right position, a lower left position and a lower right position on the single image pickup element. Thus, four electronic images of the object can be obtained and an electron image output section 107 composition the images into one electronic image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographing apparatus for photoelectrically converting a subject image formed by an image pickup optical system by a two-dimensional image pickup device and recording it as an electronic image.

[0002]

2. Description of the Related Art In a photographing apparatus which photoelectrically converts a subject image formed by an image pickup optical system by an image pickup device and records it as an electronic image, a method of photographing a subject at high resolution without increasing the resolution of the image pickup device is known. The object image combined by the imaging optical system is reflected toward a one-dimensional image pickup device by a reflecting mirror rotatable at a small angle, and a plurality of images are taken by changing the angle of the reflecting mirror. A method of synthesizing an image is known (Japanese Patent Laid-Open No. 10-21019).
8).

[0003]

SUMMARY OF THE INVENTION In the above method,
More precise rotation control is required in proportion to the distance between the reflecting mirror and the image sensor, and the rotation speed needs to be changed depending on the position of the rotation angle, which complicates the processing and the reflected image of the subject. When photographing is performed by a single image sensor, it takes a very long time to generate one image, and there is a problem that the influence of scattered light causes a decrease in the contrast of an electronic image.

Accordingly, it is an object of the present invention to provide an image pickup apparatus which is miniaturized and can shoot a subject with high resolution and high contrast.

[0005]

According to a first aspect of the present invention, a two-dimensional pinhole filter is disposed in front of and in close proximity to a two-dimensional image sensor. The two-dimensional image sensor is covered with a microlens filter in which a number of lenses having extremely small irregularities are arranged on the image sensor, and plays a role of refracting light incident on the image sensor toward a light receiving portion of the image sensor. Thus, it is possible to receive light even if light is incident on any part on the image sensor.

The two-dimensional pinhole filter has a one-to-one correspondence with each single image sensor of the two-dimensional image sensor, and has a size of 1 / n or less (n is an integer of 2 or more) of the size of the single image sensor. ) Is pierced in the same arrangement as the single image sensor, and the subject image input by the subject image input unit is converted into fine parallel rays by passing through the pinhole. The corresponding single image sensor is made to receive light. The two-dimensional image sensor or the two-dimensional pinhole filter is moved slightly in the vertical and / or horizontal directions so that the portions where the parallel rays passing through the pinholes reach the corresponding single image sensor do not overlap with each other. Then, a plurality of electronic images of the subject are obtained. The plurality of electronic images are synthesized by the electronic image output unit based on the positional information of the two-dimensional image sensor when each electronic image is obtained.

As described above, by limiting the amount of light by the pinhole filter, it is possible to perform high-resolution imaging irrespective of the resolution of the two-dimensional image sensor, and to place the two-dimensional pinhole filter close to the two-dimensional image sensor. By doing so, scattered light is removed, and high-contrast imaging is possible.

In the second embodiment of the present invention, a liquid crystal shutter is used instead of the two-dimensional pinhole filter. This liquid crystal shutter is one-to-one with each single image sensor of the two-dimensional image sensor.
M × n (m, n) having the same size as a single image sensor
(n is an integer of 2 or more). Then, control for transmitting incident light only for one or a plurality of corresponding pixels in each liquid crystal block of the liquid crystal shutter is sequentially performed for all pixels in the liquid crystal block. Are obtained.

[0009]

Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, a photographing apparatus according to an embodiment of the present invention includes a subject image input unit 101, a two-dimensional pinhole filter 102, a two-dimensional image sensor 103, and a driving unit 10.
4, an A / D converter 105, and a synthesis processing circuit 106. Here, the A / D converter 105 and the synthesis processing circuit 106 constitute an electronic image output unit 107.

A subject image input unit 101 inputs a subject image by an imaging optical system. The input subject image is converted into fine parallel rays by passing through minute pinholes of the two-dimensional pinhole filter 102. The parallel rays are received by the two-dimensional image sensor 103 and are converted into analog electric signals. The two-dimensional imaging device 103 is covered with a microlens filter (not shown) on which a number of extremely small concave and convex lenses are arranged. The driving unit 104 is used to change each light beam reaching the two-dimensional image sensor 103.
The three-dimensional image sensor 103 is moved by a small distance in the vertical and horizontal directions. The analog electric signal output from the two-dimensional image sensor 103 is converted into a digital signal by the A / D converter 105, and is output to the synthesizing circuit 106 based on the plurality of images and the position information of the two-dimensional image sensor 103 at that time. The two electronic images are combined and output.

FIG. 2 shows a two-dimensional pinhole filter 102 and
The details of the two-dimensional image sensor 103 are shown. 2D imaging
In this embodiment, the element 103 is a 3 × 3 matrix of a single image sensor.
Consists of Trix. 2D pinhole filter
Reference numeral 102 denotes the vertical and horizontal lengths of the single image sensor, respectively.
Let a and b be rectangles of a / 2 and b / 2, respectively.
Between the vertical a and horizontal b corresponding to each image sensor
It is open at a distance. Therefore, reaching the pinhole
Incident light (for example, incident light L₁, L_TwoOnly) pinhole
It passes and the other incident light is blocked. Where
As described above, the two-dimensional image sensor 103 is
A / 2 in the vertical direction by the driving unit 104 using
Each pinhole is moved slightly by b / 2 in the horizontal direction.
Position on the single image sensor changes to upper left, upper right, lower left, lower right.
Become FIG. 3 shows the movement of the two-dimensional image sensor 103 due to this movement.
Therefore, the incident light L₁₁, L₁₂,
L₁₃, L ₁₄Is reached. Pinhole
The incident light that has passed is the upper left and upper right parts of each single image sensor.
Minutes, lower left, lower right
4 (1), (2), (3),
Assuming that (4), these four images are combined by the synthesis processing circuit 10
6 and 4 times the spatial resolution of the two-dimensional image sensor 103
An image having a degree (FIG. 4 (5)) is output. This synthesis process
A method of creating an image (FIG. 4 (5)) by the logic circuit 106 will be described.
I will tell. The pixels of the image (FIG. 4 (5)) are mutually
The two-dimensional image sensor is divided into a plurality of non-overlapping blocks.
One-to-one correspondence with the single image sensor
Incident light on each element when an image is captured for each lock
Corresponding to the image (FIGS. 4A to 4D) according to the position of
The luminance information of the pixel is input to complete the entire image.

When a plurality of electronic images are obtained as described above, the operation of moving, stopping, and imaging the two-dimensional image sensor 103 for one electronic image (one image frame) is performed four times (when the resolution is doubled). ) Must be repeated. Here, as the time of each operation, when a piezo element is used as the moving means of the pinhole filter, 0.1 ms and 0.1
ms and 6 ms (when 30 frames of video are presented per second) are general guidelines. Note that the shutter opening time may be changed depending on the object to be imaged.

The two-dimensional pinhole filter 102 may be moved with respect to the two-dimensional liquid crystal element 103. Also, the pinhole may have another shape such as a circle,
The size may be such that a part that is not received by the two-dimensional image sensor 103 is generated.

Referring to FIG. 5, a photographing apparatus according to another embodiment of the present invention includes a subject image input unit 101 and a liquid crystal shutter 1.
08, the liquid crystal shutter control unit 109, and the two-dimensional image sensor 1
03, an A / D converter 105, and a synthesis processing circuit 106.

The liquid crystal shutter 108 is a two-dimensional image sensor 1
The two-dimensional image sensor 103 has a spatial resolution twice as large as that of the two-dimensional image sensor 103, and the adjacent non-overlapping blocks of every four pixels forming a square correspond to the single-element image sensor 103 that constitutes the two-dimensional image sensor 103 one by one. In FIG. 6, the incident light L ₁
And L ₂ are a part of the incident light input from the subject image input unit 101 to the liquid crystal shutter 108. FIG. 7A shows a transmission pattern when the incident lights L ₁ and L ₂ control the liquid crystal shutter 108 so that only the upper left pixel transmits the incident light in each block.
A white pixel means transmitting incident light, and a black pixel means not transmitting. Hereinafter, similarly, the liquid crystal shutter 108 is controlled to change the pattern (FIG. 7 (2)), the pattern (FIG. 7 (3)), and the pattern (FIG. 7 (4)) to perform photographing with the two-dimensional image sensor 103. The obtained results are assumed to be the images of FIGS. 4 (1), (2), (3) and (4), respectively. The method of synthesizing an image (FIG. 4 (5)) from these four images is the same as in the embodiment of FIG.

The control of the liquid crystal shutter by the liquid crystal shutter control unit 109 is performed by applying (transmitting) a voltage to each pixel.
/ Non-application (interruption) is controlled. Also,
A plurality of pixels may be simultaneously transmitted to one single image sensor.

In the above embodiment, the two-dimensional pinhole filter and the liquid crystal shutter have a spatial resolution twice as large as that of the two-dimensional image pickup device. Shooting becomes possible. For example, considering the case of three times, the diameter of a thin parallel light beam that has passed through a two-dimensional pinhole filter and a liquid crystal shutter is 1/3 of that of a single image sensor, and the position on the single image sensor that reaches the upper left, middle upper, upper right corners The three-dimensional imaging device 3 is obtained by performing synthesis processing from nine images taken while changing each light ray so that the light rays do not overlap each other, such as left middle, middle middle, right middle, lower left, middle lower, and lower right.
An image having twice the spatial resolution can be obtained.

[0019]

As described above, according to the present invention, high-resolution imaging can be performed without depending on the spatial resolution of the two-dimensional imaging element used for imaging and without increasing the size of the two-dimensional imaging element. Further, by removing the scattered light, a high-contrast image can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a photographing apparatus according to an embodiment of the present invention.

FIG. 2 shows a subject image conversion unit 102 in the photographing apparatus shown in FIG.
FIG. 4 is a diagram illustrating a relationship between the light receiving unit and a parallel light receiving unit;

FIG. 3 is a diagram illustrating a state of incident light on a two-dimensional image sensor 103 in FIG. 2;

FIG. 4 is an explanatory diagram of a method of synthesizing an image in a synthesis processing circuit.

FIG. 5 is a block diagram of a photographing apparatus according to another embodiment of the present invention.

6 is an explanatory diagram illustrating a relationship between a subject image conversion unit 102 and a parallel light receiving unit 103 in the high-resolution imaging device in FIG. 5;

FIG. 7 is an explanatory diagram of a control pattern of the liquid crystal shutter 108.

[Explanation of symbols]

 Reference Signs List 101 subject image input unit 102 two-dimensional pinhole filter 103 two-dimensional image sensor 104 drive unit 105 A / D converter 106 synthesis processing circuit 107 electronic image output unit 108 liquid crystal shutter 109 liquid crystal shutter control unit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Haruhiko Kojima 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term within Nippon Telegraph and Telephone Corporation (reference) 5C022 AB31 AB68 AC00 5C024 CA11 EA07 EA10 FA01 FA14 HA14 HA17 JA05

Claims (2)

[Claims] An imaging apparatus for photoelectrically converting and recording a subject image formed by an imaging optical system, comprising: a subject image input unit for inputting a subject image; and a plurality of single image sensors arranged two-dimensionally. A two-dimensional image sensor that converts a received light beam into an analog signal; and a one-to-one correspondence with each single image sensor of the two-dimensional image sensor, and the size is 1 / n or less of the size of the single image sensor ( (n is an integer of 2 or more), a minute pinhole is provided in the same arrangement as the single image sensor, and the subject image input by the subject image input unit is converted into fine parallel rays by passing through the pinhole. 2 is provided in parallel with, and close to, the parallel light receiving unit, for receiving light by a single image sensor corresponding to each pinhole.
A two-dimensional pinhole filter, and one of the two-dimensional image sensor and the two-dimensional pinhole filter is arranged in parallel with the other such that portions where parallel rays passing through each pinhole reach the corresponding single image sensor do not overlap with each other, A drive unit for micro-moving vertically and / or horizontally, and a plurality of electronic images of a subject obtained by the two-dimensional imaging device by finely moving the two-dimensional imaging device or the two-dimensional pinhole filter; An imaging device having an electronic image output unit that combines a certain analog signal based on the position information of the two-dimensional imaging device or the two-dimensional pinhole filter when each electronic image is obtained and outputs one electronic image apparatus. 2. An imaging apparatus for photoelectrically converting and recording a subject image formed by an imaging optical system, comprising: a subject image input unit for inputting a subject image; and a plurality of single image sensors arranged two-dimensionally. A two-dimensional image sensor for converting a received light beam into an analog signal; m × n (m, n) having the same size as the single image sensor corresponding to each single image sensor of the two-dimensional image sensor in a one-to-one correspondence. Is 2
A plurality of liquid crystal blocks composed of pixels)
A liquid crystal shutter provided in parallel with and in close proximity to the two-dimensional image pickup device; and a liquid crystal shutter for controlling the liquid crystal shutter to transmit incident light only to one or a plurality of corresponding pixels in each liquid crystal block. A liquid crystal shutter control unit that sequentially performs all of the pixels, and an analog signal that is a plurality of electronic images of a subject obtained by the two-dimensional image sensor by controlling the liquid crystal shutter with the liquid crystal shutter control unit. An image pickup apparatus comprising: an electronic image output unit that synthesizes based on positional information of pixels that have transmitted incident light of the liquid crystal shutter when each electronic image is obtained, and outputs one electronic image.