JPH06197287A - Picture input device - Google Patents

Abstract

PURPOSE:To obtain picture information with high resolution with a few number of image pickup elements by supplying a picture light from plural picture elements to the image pickup elements via an optical switch array comprising optical switches of desired arrangement. CONSTITUTION:A picture light from plural picture elements A11-A44 or the like of a picture 1 is made incident in photoelectric conversion areas P11-P22 split into four of an image pickup element 3 via an optical switch array 2 comprising optical switches of the same arrangement as the picture elements A11-A44. Through the constitution above employing the array 2, an input picture light incident in each of the split areas P11-P22 is read in time division by deviating timewise the light. Thus, a high resolution picture is obtained by a few image pickup number.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device for electrically obtaining an image by photoelectric conversion means, and more particularly to an image input device suitable for obtaining a high resolution image.

[0002]

2. Description of the Related Art A solid-state image pickup device used in an image input device has pixels including photoelectric conversion means arranged one-dimensionally or two-dimensionally and converts an optical signal from an image pickup object into an electric signal.
It is for obtaining image information. The resolution of the image information obtained by the solid-state image sensor depends on the number of pixels in the solid-state image sensor, and the resolution of the image information is increased, that is, the number of pixels is increased to obtain a finer image (higher pixel density). ) Is necessary.

[0003]

However, in the past, in order to increase the density of the above-mentioned pixels, it was necessary to reduce the pixel area, which inevitably required a higher manufacturing technology, and Manufacturing becomes difficult and therefore
Inevitably, the reliability of the device was lowered and the price was increased. The present invention has been made in view of the above circumstances, and an object thereof is to provide an image input device capable of obtaining high-resolution image information with a small number of pixels.

[0004]

In order to achieve the above object, in the image input apparatus of the present invention, as shown in FIG. 1, for example, as shown in FIG. An optical switch array 2 that shields or transmits the input image light is provided on the input side, and the optical switch array 2 is one-dimensional or two-dimensional within the input image light region corresponding to, for example, P11 of each of the plurality of photoelectric conversion units. 1 is provided with an array configuration of optical switches that are divided into a plurality (for example, 2 × 2 in FIG. 1) of the array of FIG. (A position corresponding to the position) corresponding to the above position, and a transmission / shading control unit for transmitting the corresponding position and shielding the other, and a photoelectric conversion hand of the pixel P11, for example, via the transmission optical switch in association with the control of the transmission / shading. And further comprising a means for reading the image signal by the image input to.

Here, the optical switch array 2 is composed of an optical mask 21 having apertures B11 to B22, for example, as shown in FIG. 3, and the transmission / shading control means sets the optical mask 21 to the optical axis. The position of the aperture may be controlled by vertically changing the position vertically or horizontally.

Alternatively, as shown in FIG. 4, the optical switch is made of a material having a characteristic that the light transmittance changes with the application of a voltage, and the transmission / shielding control means for this is controlled by the position control of the voltage application to the material. It may be performed.

In this case, the optical switch may be made of polymer dispersed liquid crystal.

Generally, when the resolution is high as described above, the screen capturing speed tends to be slow, but in the case of screen alignment, the capturing speed is preferably high. In order to be able to cope with such a thing,
If the area of the transmissive region of the optical switch array can be made variable by changing the number of the plurality of optical switches that are in the transmissive state at the same time, it is possible to increase the definition while increasing the capturing speed. Yes desirable.

The above-mentioned image pickup means of the present invention can be applied to an image pickup tube. That is, the means for reading out the image signal via the optical switch is configured to read out the signal charges obtained by the photoelectric conversion means via the optical switch by electron beam scanning. In this case, the optical switch is It is preferable to have a plurality of electron beams in the image region corresponding to the size of one electron beam, because the resolution can be improved.

[0010]

In the present invention, an optical switch array is provided on the input side of the photoelectric conversion means, and an optical switch capable of further dividing the input image area corresponding to the photoelectric conversion means into a plurality of parts is provided. As a result, the optical switch array can partially block and transmit the input image light. And this
The image light input to the photoelectric conversion means is temporally divided. At this time, the image light that is temporally divided and input is obtained by dividing the original image into several regions, which are converted into signal charges by the photoelectric conversion means and read out. The reading is performed by interlocking with the control of transmission and light shielding of the optical switch. That is, the image divided into regions is read with a temporal shift. By doing so, it is possible to obtain high-resolution image information without increasing the number of pixels of the image pickup element itself to increase the density.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a basic configuration of image input according to the present invention. In the figure, 1 is an image to be input, 2 is an optical switch array,
Reference numeral 3 is a solid-state image sensor. In the solid-state image sensor 3, 2 × 2 pixels P11, P12, P21, P22 are two-dimensionally arranged, and a photoelectric conversion unit is provided in each pixel. If there is no optical switch array 2 now, image 1
Are the four regions (A11, A1) indicated by the dashed line in the figure.
2, A21, A22), (A13, A14, A23, A
24), (A31, A32, A41, A42), (A3
3, A34, A43, A44) and read. On the other hand, by providing the optical switch array 2 between the image 1 and the solid-state image sensor 3, the image 1 can be divided into more areas, that is, the image 1 can be read with higher precision. The optical switch array 2 has a configuration in which optical switches are two-dimensionally arranged, and FIG. 1 shows a configuration in which 2 × 2 optical switches are arranged for one pixel. Each optical switch is controlled so as to block or transmit the light incident thereon. In FIG. 1, the shaded optical switch indicates a light-shielding state, and therefore, image light in a quarter area of one pixel is in a transmission state. In this state, as shown in FIG. 2A, in the solid-state image sensor 3, the image light of the four filled areas A11, A13, A31, and A33 of the image 1 is made incident on the respective pixels, and photoelectric conversion is performed. The electric signal is converted by the converting means. Next, the solid-state image sensor 3 is selected by selecting a different light shielding / transmitting state of the optical switch array.
2 shows the area of the image 1 converted into an electric signal by
It can be changed as in (b), (c) and (d).
Therefore, the image 1 can be read by being divided into 4 × 4 regions. In this way, by providing the optical switch array 2 between the image 1 to be input and the solid-state image sensor 3, the image can be divided and read by more pixels than the solid-state image sensor has, and the resolution can be improved. You can Although FIG. 1 shows an example in which 2 × 2 optical switches are provided for one pixel, the number and configuration of optical switches are not limited to this, and 3 × 3 or 4 optical switches are provided.
Any combination such as × 2 can be taken. Since the image is divided into areas and read by the number of the optical switches, it is possible to read the image with higher precision by increasing the number of the optical switches.

FIG. 3 is a diagram showing a configuration example of an image input apparatus according to the present invention. As an optical switch array, a solid-state image sensor 3 is used.
Aperture B that limits the light incident on each pixel of
Optical mask 21 provided with 11, B12, B21, B22
An example configured by In this configuration, only the light in the area of the image 1 corresponding to the aperture is incident on the solid-state image sensor 3. Therefore, the optical mask 21 is attached to the solid-state image sensor 3
By moving up and down and left and right in the direction perpendicular to the optical axis within the range of the pixel pitch of 1, the image 1 is divided and read by the number of pixels larger than the number of pixels of the solid-state image sensor 3 as described in FIG. FIG. 4 is a diagram showing another configuration example of the image input device according to the present invention, in which the resolution can be improved. As the optical switch array, a material having a characteristic of electrically changing the light transmittance is used. A configuration example is shown.
In FIG. 4, only the optical switch array portion is shown. Figure 4
In the optical switch array shown in (1), stripe-shaped transparent electrodes 41, 42, 43, 44 are formed on one surface of a material 31 formed in a plate shape and having a characteristic of electrically changing the light transmittance, and the other is formed. On the surface, the transparent electrodes 41, 42, 43,
Striped transparent electrodes 51, 52, 53, 54 are formed so as to be orthogonal to 44. Switches 61 and 62 are connected to these transparent electrodes so that a potential can be selectively applied. Now, as shown in FIG. 4, the voltage V is applied to the transparent electrodes 41, 43 by the transparent electrodes 51, 5
Consider a case where a ground voltage is applied to 3 and the other transparent electrodes are in a floating state. In this case, the material 3 in the region where the transparent electrodes 41, 43 and 51, 53 face each other.
An electric field is applied to 1 and no electric field is applied to other regions. Therefore, the transmittance of light can be changed depending on the presence or absence of this electric field, and the optical switch array can be configured. As such a material whose light transmittance changes depending on the presence or absence of an electric field, for example, a Society for Information Display 90
Proceedings 220 to 223 (1990
Year) (Society for Information Display 90, 199
0, pp.220-223), polymer-dispersed liquid crystals can be used. In this configuration example, there is no need to move the position like the optical mask shown in FIG.
An optical switch array can be electrically constructed.

FIG. 5 is a diagram showing an example of the overall configuration of the image input apparatus according to the present invention. Reference numeral 10 denotes an image pickup target to be input, which may be, for example, a document held by a support or a fluorescent plate in the X-ray image pickup apparatus. Reference numeral 2 denotes the optical switch array described so far, which is composed of the optical mask and the liquid crystal plate shown in FIG. 3 or 4. Reference numeral 3 denotes a solid-state image pickup device having M × N pixels, which is arranged so that an image is formed on the solid-state image pickup device 3 by an image forming lens 4. Reference numeral 5 denotes an optical switch driving section for driving the optical switch array 2, which controls the position of the optical switch array 2 when it is configured by the optical mask shown in FIG. 3, and as shown in FIG. When it is formed of a plate, it controls the opening and closing of the switches 61 and 62. An image sensor driving unit 6 drives the solid-state image sensor 3. An image output from the solid-state image sensor 3 whose operation is controlled by the image sensor driver 6 is input to the signal processor 7. Reference numeral 8 is a control unit that controls the entire operation.
In the present invention, the optical switch array 2 divides the image into several regions, which are then incident on the solid-state image sensor 3. Therefore, the operations of the optical switch array 2 and the solid-state imaging device 3 need to be controlled in conjunction with each other. Also optical switch array 2
If each pixel is composed of 2 × 2 optical switches, the image is divided into 2M × 2N regions,
Since the images of N regions are captured in four times, the images captured in these time divisions are combined into one image in the signal processing unit 7. This image composition can be easily performed by using the storage means.

Now, in the configuration example of the optical switch array shown in FIG. 4, since the blocking and transmission of the image light can be electrically controlled, the size of the area of the image captured at one time can be easily changed. For example, as shown in FIG. 6, the transparent electrode 4
A voltage V is applied to 1, 42, 43, 44, and transparent electrodes 51, 5
Switch 6 to apply ground voltage to 2, 53, 54
Controlling Nos. 1 and 62 applies an electric field over the entire region, so that the entire image light is transmitted as shown in FIG. In this case, the image is substantially divided into 2 × 2 regions and captured as in the conventional case. However, in this case, a large amount of signal charges can be obtained because the amount of light incident on one pixel increases. Therefore, the operation of the optical switch array 2 can be controlled according to the imaging condition or the imaging purpose. As such an example, the optical switch array 2 is shown in FIG.
The original is imaged in the moving image mode in the state shown in, and the original to be captured on the display is aligned in a short time. After that, the optical switch array 2 is brought into the state shown in FIG. 4, and the image of the original can be taken in high definition over a certain period of time.

In the present invention, an image corresponding to one pixel of the solid-state image pickup device is divided into several regions by the optical switch array and taken in to obtain high resolution. Therefore, an element having as large an aperture ratio as possible is desired as a solid-state image pickup element. As such an element, for example, a solid-state image pickup element provided with a microlens for condensing incident light on a photoelectric conversion means as described in page 31 to page 39 (May 1990) of image information, Alternatively, it is possible to use a solid-state image sensor in which a photoconductive film is laminated.

Although the present invention has been described with reference to some examples, the present invention is not limited to the above-described embodiments, and various modifications can be carried out. In the above-mentioned embodiment, the description has been given mainly using the two-dimensional solid-state image sensor, but it may be a one-dimensional solid-state image sensor. Further, the solid-state image pickup device has been described as the so-called image pickup means for converting the image light into an electric image so that the gist of the present invention can be easily understood, but an image pickup tube may be used as the image pickup means.
In the image pickup tube, since the image information is obtained by scanning the signal charges generated by the photoelectric conversion means with the electron beam, there is no concept of a pixel. However, since the electron beam has a finite size, at least the vertical resolution is It is defined by the scanning area of the electron beam. Therefore, even when the image pickup tube is used, the resolution can be improved by dividing and capturing the image region corresponding to the scanning region of one electron beam by the optical switch array. Of course, as an image pickup tube, the Journal of the Television Society, Vol. 42, No. 8
No. 780 to 786 (1988), an image pickup tube utilizing the avalanche multiplication phenomenon can be used to improve the sensitivity and compensate for the decrease in the amount of incident light due to image division. it can.

[0017]

As described above, according to the present invention, 1
The image area corresponding to one pixel can be captured by dividing it into several areas by the optical switch array, and high resolution can be achieved.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of an image input apparatus of the present invention.

FIG. 2 is a diagram showing the principle of image input according to the present invention.

FIG. 3 is a diagram showing a configuration example of an image input device according to the present invention.

FIG. 4 is a diagram showing another configuration example of the image input device according to the present invention.

FIG. 5 is an overall configuration diagram of an image input device according to the present invention.

FIG. 6 is a diagram showing another operation example of the configuration example shown in FIG. 4.

FIG. 7 shows an image according to FIG.

[Explanation of symbols]

1 ... Image, 2 ... Optical switch array, 3 ... Solid-state image sensor, A11 to A44 ... Image area, P11 to P2
2 ... Pixel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Hatae 1-280 Higashi Koikeku, Kokubunji, Tokyo Inside Central Research Laboratory, Hitachi, Ltd. (72) Inventor Yasuo Tanaka 1-280, Higashi Koikeku, Kokubunji, Tokyo Hitachi, Ltd. Central Research Center

Claims (6)

[Claims] 1. An image input device having a plurality of photoelectric conversion means, wherein input image light is converted into an image signal by the plurality of photoelectric conversion means to obtain image information, wherein an input side of the plurality of photoelectric conversion means is provided. An optical switch array for blocking or transmitting the input image light is provided, and the optical switch array divides the input image light region corresponding to each of the plurality of photoelectric conversion units into a plurality of one-dimensional or two-dimensional arrays. An optical switch array structure is provided, and a transmission / shading control unit for selecting an array position for transmitting the input image light in the array structure and transmitting the corresponding position and shielding the other, and interlocking with the transmission / shading control. An image input device comprising means for reading out the image signal by image input to the photoelectric conversion means via a transmissive optical switch. 2. The image input device according to claim 1, wherein
The optical switch array is composed of an optical mask having an aperture, and the transmission / shielding control means changes the position of the optical mask in a direction perpendicular to the optical axis to control the position of the aperture. Image input device. 3. The image input device according to claim 1, wherein
The image input device, wherein the optical switch is made of a material having a characteristic that the light transmittance changes by applying a voltage, and the transmission / light-shielding control means is controlled by position control of voltage application to the material. 4. The image input device according to claim 3,
An image input device characterized in that the optical switch is composed of a polymer-dispersed liquid crystal. 5. The image input device according to claim 3 or 4, wherein the area of the transmission region of the optical switch array can be made variable by changing the number of the plurality of optical switches that are in the transmission state at the same time. An image input device characterized by. 6. The image input device according to any one of claims 1 to 5, wherein the means for reading out an image signal via the optical switch is obtained by the photoelectric conversion means via the optical switch. An image input device having a structure for reading out signal charges by electron beam scanning, and having a plurality of the optical switches in an image region corresponding to the size of one electron beam.