JPH03113960A - Picture input device - Google Patents

Abstract

PURPOSE:To read a color picture by making each separated color light into a photodetection sensor in order with a shutter shutting light for each prescribed period. CONSTITUTION:An optical section 2 consists of a color filter 21 separating an incident light from an original face into three primary colors (red, green, blue) and a liquid crystal shutter 22 passing each color light passing through the filter 21 according to a scanning signal Ss. The operator scans the area of a picture to be fetched with a sensor section 4 at a prescribed moving speed. Then the sensor section 4 scanning the picture outputs a picture signal is for each color (red, green, blue) at a period (several msec) not affected with the moving speed. Then the picture signal Is is inputted to an A/D converter 6 via an amplifier 5 and written in a storage area of a memory 10 sequentially by a control circuit 7 as a picture data ld for each color.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an input device for a computer or the like, and in particular,
The present invention relates to an image input device that can read color images.

"Prior Art" In recent years, human-powered image devices that easily input image data into personal computers, word processors, and the like have been put into practical use. This image input device is composed of a scanning section and a signal processing section, and when reading an image, the scanning section is set on the surface of a document and is caused to scan the image to be read at a constant moving speed. As a result, the one-dimensional C0D (charge coupled device) image sensor provided in the scanning section generates an image signal of the scanned area and outputs it to the signal processing section.

The signal processing section digitizes this image signal and outputs it to an external device as image data.

"Problem to be solved by the invention" By the way, in the above-mentioned simple image input device,
Generally, images are detected as monochrome contrast information, and there is a problem in that color images cannot be read.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an image input device that can read color images.

[Means for Solving the Problems] The present invention includes a light-receiving sensor that converts light incident from the surface of a document into an image signal and outputs the image signal, and a light-receiving sensor that is provided for each pixel of the light-receiving sensor and separates the incident light into three primary colors. a color filter, a shutter means provided for each color of the color filter and for sequentially passing each color light at regular intervals, a drive means for driving the shutter and shutter means, and a shutter means for each color outputted from the light receiving sensor. It is characterized by comprising a signal processing means for synthesizing image signals and generating a color image signal.

"Operation" According to the present invention, the color filter separates the light incident from the document surface into the three primary colors of red, green, and blue. The separated colored lights are sequentially incident on the light receiving sensor by a shutter that blocks light at regular intervals. As a result, image signals for each color are output from the light receiving sensor, and the output image signals for each color are combined to form a color image.

``Embodiment'' Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an image input device 1 according to the same embodiment. In FIG. 1, Lw is a white light source for imaging, and M is a reflecting mirror, which changes the optical path of the light from the white light source Lw and irradiates the document surface. 2 is an optical section;
It is composed of a color filter 21 that separates light incident from the document surface into three primary colors (red, green, and blue), and a liquid crystal shutter 22 that sequentially passes each color light transmitted through the filter 21 in accordance with a scanning signal Ss. 3 is a light receiving section.

The light receiving section 3 receives the light of each color sequentially incident through the optical section 2, converts the intensity of the received light into an image signal S,
The converted signal rs is output to the next stage according to the drive signal Sd. The optical section 2 and the light receiving section 3 constitute a sensor section 4. The configuration of this sensor section 4 will be described in detail with reference to FIGS. 2 and 3.

FIG. 2 is a perspective view showing a schematic structure of the sensor section 4. FIG.

The sensor section 4 shown in this figure has a liquid crystal shutter 22 formed in close contact with the light receiving surface of the light receiving section 3, and further includes a liquid crystal shutter 22.
It has a hierarchical structure in which a color filter 21 is formed on top of the color filter 21. In such a sensor section 4, 3-1 to 3-N are pixels arranged one-dimensionally on the light-receiving surface of the light-receiving section 3. The image signal Is output from each pixel 3-1 to 3-N is
Corresponds to one horizontal line of the image. 22-1 to 22N are
This is a liquid crystal panel constituting the liquid crystal shutter 22, and each of the liquid crystal panels 22-1 to 22-N is connected to each pixel 3-1 to 3-N.
For example, in pixel 3-1, liquid crystal panels 22-1 to 22-3 are arranged. The color filter 21 is composed of a red filter 21a, a green filter 21b, and a blue filter 21c,
Each transmits light in a wavelength range according to the spectral characteristics of the eight bodies. These filters 21 a, 21 b, and 21 c are arranged in order on the liquid crystal panels 22-1 to 22-N. That is, red filters 21a are arranged in the upper row in the longitudinal direction of the color filters 21, green filters 21b are arranged in the middle row, and blue filters 21c are arranged in the lower row.

FIG. 3 is a cross-sectional view showing the cross-sectional structure of the sensor section 4. As shown in FIG.

In the liquid crystal shutter 22 shown in this figure, 22a-1,
22a-2 is a polarizing plate arranged so that the polarization axes are orthogonal to each other. 22b is a glass substrate, and a liquid crystal 22d having positive dielectric anisotropy is sealed between the glass substrates 22b so as to have optical rotation. 22cm1 is a common electrode formed of a transparent conductive film. 22a-2 is an electrode provided for each liquid crystal panel 22-1 to 22-N, and this electrode 22cm2 is a thin film transistor (TPT).
and a transparent conductive film. FIG. 4 shows the operating principle of the liquid crystal shutter 22 having such a configuration.

Figure (a) shows the case where no voltage is applied to the electrodes 22 cm x 1.22 cm2. In this case, the incident light propagates along the molecular axis of the liquid crystal molecules, which rotates the plane of polarization by 90 degrees. Transmits light. On the other hand, when the voltage shown in the figure (b) is applied, what happens to the liquid crystal molecules? [Because it changes its arrangement to the circumferential gyrus, it loses its optical rotation, and as a result, it no longer transmits light.

Next, 5 is each color (red, green, blue) output from the light receiving section 3.
This is an amplifier that amplifies the level of the image signal Is for each light. 6
is an A/D (analog/digital) converter, which digitizes the output signal of the amplifier 6 and outputs image data Id. 7 is a control circuit composed of a microprocessor and the like. The control circuit 7 outputs the sampling clock CLK, and also takes in the image data Id from the A/D converter 6 and sequentially writes it into the storage area of the memory 10. Further, the image data Id for each color light written in the memory 10 is read out, converted into color image data Dc, and output. Reference numeral 8 denotes a drive circuit which receives the sampling clock CLK from the control circuit 7 and transfers the charge accumulated in each pixel 3-1 to 3-N of the light receiving section 3, that is, the image signal Is, to the next stage. generate a signal Sd;
Output. 9 is a liquid crystal drive circuit which receives the sampling clock CLK from the control circuit 10 and drives the liquid crystal shutter 2.
A scanning signal Ss for controlling 2 is generated and output. This scanning signal Ss controls the liquid crystal shutter 22 so that each color light incident on the light receiving section 3 is in the order of red light, green light, and blue light. For example, when red light is made to enter the light receiving section 3, a scanning signal Ss is applied to the liquid crystal panels 22-2 to 22-N provided in the middle row and the lower row of the color filter 21 to put them in a light-blocking state. The memory 10 is a dynamic R
The control circuit 7 writes image data Id during image capture, and reads these image data Id after completion of capture. Reference numeral 11 denotes an interface circuit, which receives color image data Dc output in parallel from the control circuit 7, converts it into a serial data format, and outputs it.

Next, the image capturing operation of the image input device 1 having the above configuration will be explained. First, when the power of the image input device l is turned on by the operator, the built-in program of the control circuit 7 is reset.
0 initialization, then the sampling clock CLK
Start sending. If a color image is to be captured now, the operator sets the sensor unit 4 on the document surface and presses the capture start switch (path shown).

Next, the image input device 1 whose switch is pressed turns on the white light source Lw, and illuminates the document surface with the reflecting mirror M. Next, the operator selects the area of the image to be captured by the sensor unit 4.
to scan at a constant moving speed. Next, the sensor unit 4 that scans the image generates an image signal Is for each color (red, green, blue) at a period (several m5ec) that is not affected by the moving speed.
Output. This image signal Is is inputted to the A/D converter 6 via the amplifier 5, and is sequentially written into the storage area of the memory 10 by the control circuit 7 as image data Id for each color. Next, when the scanning of the sensor section 4 is completed, the control circuit 7 outputs the image data 1d from the memo IJIO.
is read out, and the read image data Id for each color (red, green, blue) is combined with color image data Dc corresponding to each pixel 3-1 to 3-N, and output to the interface circuit 11. Next, the interface circuit 11 that receives the color image data Dc converts the data Dc into a serial data format and outputs it to a personal combinator, word processor, etc. using a serial interface standard such as R3-232C. .

The details of the image input device 1 have been described above. In the above embodiment, the color filter 21 is formed on the liquid crystal shutter 22, but the color filter 21 may also be provided in each of the liquid crystal panels 22-1 to 22-N constituting the liquid crystal shutter 22. It is possible.

"Effects of the Invention" As explained above, according to the present invention, there is provided a light receiving sensor that converts light incident from the document surface into an image signal and outputs the image signal;
a color filter that is provided for each pixel of the light receiving sensor and separates incident light into three primary colors; a shutter means that is provided for each color of the color filter and that sequentially passes each color light at regular intervals; and a shutter means that separates the incident light into three primary colors; A driving means for driving and combining image signals for each color output from the light receiving sensor,
Since a signal processing means for generating a color image signal is provided, there is an effect that a color image can be read.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an image input device according to an embodiment of the present invention, FIG. 2 is a perspective view showing a schematic structure of a sensor section in the same embodiment, and FIG. 3 is a block diagram showing a schematic structure of a sensor section in the same embodiment. FIG. 4, a cross-sectional view showing the cross-sectional structure, is a diagram for explaining the operation of the liquid crystal shutter in the same embodiment. 3... Light receiving section, 9... Liquid crystal drive circuit,
7... Control circuit, 22... Liquid crystal shutter, 21... Color filter,

Claims (1)

[Scope of Claims] (a) A light-receiving sensor that converts light incident from the document surface into an image signal and outputs the image signal; (b) A color sensor provided for each pixel of the light-receiving sensor that separates the incident light into three primary colors. (c) shutter means provided for each color of the color filter and for sequentially passing each color light at regular intervals; (d) drive means for driving the shutter means; and (e) from the light receiving sensor. An image input device comprising: signal processing means for synthesizing output image signals of each color to generate a color image signal.