JPH01160195A - Photoelectric converter for color reading - Google Patents

Abstract

PURPOSE:To make the number of two photodetection element arrays and shift clocks the same by providing R, G, B color filters sequentially regularly onto the photodetector of nearly square and the photodetector of nearly rectangle. CONSTITUTION:Rectangular photodetectors 1a, 2a and nearly square photodetectors, 1b, 1c, 2b, 2c are formed so as to be correspondent in the main scanning direction by locating deviation and 3 kinds of different color filters R, G, B are formed so that the rectangular photodetectors 1a, 2a are of the same kind to apply 3-color separation. Thus, the same number of photodetectors are formed to the 1st and 2nd arrays, a readout signal (clock) given to the 1st and 2nd arrays may be identical and the number of readout signals given to the photoelectric converter is saved. When the 1st and 2nd arrays are read switchingly alternately, the three color separation R, G, B signals are extracted sequentially and the processing of the output signal is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention consists of two rows of light-receiving elements arranged linearly in the main scanning direction and shifted in the sub-scanning direction.
The present invention relates to a photoelectric conversion device for color reading that can perform color separation of a color original by providing a color filter such as B.

2. Description of the Related Art As shown in FIG. 2, the conventional light-receiving element rows are arranged in two rows by shifting them in the sub-scanning direction, and the first row has a light-receiving area approximately twice that of the second row. , are composed of color filters of the same type, and the second row is composed of color filters of two different scales arranged in order to obtain R, G, and B signal outputs (for example, Japanese Patent Application Laid-Open No. Sho e1). -29
2468).

Problems to be Solved by the Invention However, according to the photoelectric conversion device as shown in FIG. 2, it is possible to obtain the G signal from the first column and the R signal and B signal from the second column. If the number of light-receiving elements in the second column and the second column are different, if you try to read out the first and second columns in the same time, the readout speed of the second column needs to be twice as fast. readout signal is required. Also, R,G
, B constitute one color pixel, but if you alternately switch the first and second columns and take out the output, it becomes necessary to further rearrange C, R, G, and B in order. When trying to take out the sheets, it is necessary to switch between taking out one sheet from the first row and two from the second row, which is complicated.

In view of this problem, the present invention provides a photoelectric conversion device for color reading that has a simple configuration and can have the same number of light-receiving elements in two rows and the same shift clock.

Means for Solving the Problems The color reading photoelectric conversion device of the present invention has light receiving elements arranged in two rows in the sub-scanning direction, and two approximately square light receiving elements in the main scanning direction. One rectangular light-receiving element having a light-receiving area approximately twice as large as that of a square light-receiving element is repeatedly arranged in order, and furthermore, in the relationship between the two rows in the sub-scanning direction, a rectangular light-receiving element and a substantially square light-receiving element 2 are arranged. It is possible to separate three colors by forming three different types of color filters on the light-receiving elements so that they are at corresponding positions in the main scanning direction, and forming three different types of color filters on the rectangular light-receiving elements so that they are of the same type. It is characterized by the following.

Since the number of working light receiving elements is the same in the first and second columns, the readout signal (clock) given to the first and second columns can be the same, and the readout signal given to the photoelectric conversion device can be can be reduced. Also, if the first and second columns are switched and read out alternately, R and G are read.

The three B color separation signals can be taken out in sequence and the output signals can be easily processed.

Embodiment FIG. 1 is a block diagram of a color reading photoelectric conversion device showing an embodiment of the present invention. 1 is the first row of light receiving elements, 2
is the second photodetector row, 3.4 is the shift register, and 5 is the shift register.
is a switching circuit.

In the first row of light receiving elements 1, light receiving elements 1a, 1b, and 1c are arranged in a line in the main scanning direction.

Further, 1b and 1c have approximately the same light-receiving area and are shaped like a square. 1a has a rectangular light-receiving surface that is long in the main scanning direction, and has a light-receiving area approximately twice that of the light-receiving elements 1b and 1C. Although omitted in this figure, 1a
, 1b, and 1c. Since a channel stopper is constructed between the light receiving elements of 1b and 1c, 1b and 1c are not perfect squares, but are approximately square when considering the arrangement pitch, and 1b and 10 in the main scanning direction. It is constructed so that the sum of the lengths is the same as 1a. Furthermore, in the main scanning direction, 1a.

They are arranged regularly around 1b and 1c. The second row of light-receiving elements 2 includes light-receiving elements 2b and 2c having the same size relationship as the first row of light-receiving elements 1.

2a, each of which is a first row of light receiving elements 1a.

They are regularly arranged in the main scanning direction so that 2b and 2c correspond to each other, and 28 corresponds to 1b and 1C.

B on the light receiving elements 1a, 1b, 1c, 2b, 2c, 2a
Color fills are arranged regularly in the order of (blue), R (red), and G (green). The color filter can be provided by vapor deposition or printing. This color filter is 1a B.

R of 2b, G of 2c, or B of 2a, R of 1b, 1
The configuration is such that the G's of c correspond to each other. Therefore, it is possible to perform color separation of R, B, and G.

For example, when reading at a density of 16 pixels, 62.6μ
m in the main scanning direction, 62.6 μm, and 31.25 μm
By configuring the light-receiving elements of 31.25 μm in the sub-scanning direction in the above-described manner, one pixel can be formed by 1a, 2b, and 2C.

In the above configuration, the number of light receiving elements in the first and second columns is the same.

3.4 is a shift register that transfers the electric charge of the light receiving element and guides it to the switching circuit, and the switching circuit 6 alternately switches the signals of the first column and the second column, R, B,
Send in the order of G. It constitutes the above-described photoelectric conversion element 6.

When light enters the light-receiving element through the color filter, charges are accumulated in the light-receiving element, a shift clock 7 is applied from the outside to the shift register, the charge from the light-receiving element is sent to the switching circuit 5, and the switching circuit 6 sends the charge into one column. The first and second columns are alternately switched and output as color signals in the order of R, B, and G.

Note that here, the light receiving element 1a has a large light receiving area.

A B (blue) color filter was used for 2a, but this is because when the photoelectric conversion element is configured with COD, the output is adjusted in consideration of the spectral sensitivity of a general fluorescent lamp (Arashi light color) and COD. This is to keep it constant, and is not limited to B (blue).

Effects of the Invention As described above, according to the present invention, the number of light-receiving elements in the first and second rows can be made the same in the main scanning direction, the same shift clock can be used, and the necessary The number of shift clocks can be reduced.

Further, the configuration of the switching circuit can be simplified by simply switching between the first and second columns, which has a great practical effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a photoelectric conversion device for color reading according to the present invention, and FIG. 2 is a plan view of main parts showing the arrangement of photoelectric conversion elements in a conventional photoelectric conversion device for color reading. 1...1st row light receiving element, 2...2nd row light receiving element, 3.4...Shift register, 5...
... Switching circuit, 6 ... Photoelectric conversion element, 7 ... Shift clock.

Claims (1)

[Claims] A light-receiving element whose light-receiving surface is approximately square, and a rectangular light-receiving element which is elongated in the scanning direction and has a light-receiving surface approximately twice as large as that of the approximately square light-receiving element, are combined with the two approximately square light-receiving elements and the rectangular light-receiving element. One light receiving element is arranged in order in the main scanning direction, and two light receiving element rows are formed in the sub scanning direction so that the rectangular light receiving element and the two substantially square light receiving elements correspond to the sub scanning direction, Furthermore, the rectangular light-receiving element is provided with the same color filter, and R, G, and B color filters are regularly provided in order on the substantially square light-receiving element and the rectangular light-receiving element. Photoelectric conversion device for reading.