JPS62112468A - Image input device - Google Patents

Abstract

PURPOSE:To input color image information by changing respective filters R, G, B to be color decomposing filters at least once during one scanning. CONSTITUTION:Original image information is made incident upon the color decomposing filter 11 as optical information. The filter 11 switches respective filters like R filter G filter B filter during one scanning to process an image signal in respective colors. The light beam passed through the filter 11 is inputted to a solid image pickup element 12 and converted into an electric signal and one line is stored in a line memory R of the 1st line memory 15. Thus, image data consisting of three primary colors, R, G, B are successively stored every line.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an image input device that converts a document image into an electrical signal and reads it, and more particularly, to an image input device that can read a color document image. (Prior Art) An image input device is a device that scans a document image using an imaging probe and converts it into an electrical signal. In recent years, solid-state image pickup devices such as COD have been developed as image pickup devices, are becoming smaller, and are being used in industry. There are two types of image input devices: one that reads a document image in monochrome and one that reads it in color. Among these, as a color image input device, there are two methods: one that uses multiple light sources and lights up different light emission distribution light sources during one scanning period to capture an image;
There is a method in which one scan is performed simultaneously using solid-state image sensors for primary colors. FIG. 11 is a diagram showing a conventional example of a color image input device, which succumbs to the former method. L for red/green on top of original 1
An ED 2 and a blue fluorescent panel 3 are arranged. First, a red LED 2 is turned on to illuminate the original 1, and the reflected light is guided to a photoelectric converter 5 by a SELFOC lens 4 and converted into an electric signal. . Next, turn on the green LED 2 and display the document 1.
is irradiated, and the reflected light is guided to a photoelectric conversion element 5 by a SELFOC lens 4. After Q, the blue fluorescent panel 3 is turned on and the same operation is performed to guide the charge to the charging conversion element 5. In these cases, the photoelectric conversion element 5 is driven by the drive circuit 6, and photoelectric conversion signals are sequentially output. When the reading for one scan is completed, the document is sent in the sub-scanning direction for one scan, and the next reading operation for each color is performed. Note that the reason why a fluorescent panel was used instead of an LED as a blue light emitting means is because the luminous efficiency of a blue light emitting LED is still at a low level at present. (Problems to be Solved by the Invention) In the precancerous method, three types of light sources must be provided, and in terms of high-speed scanning, there is a problem of afterimages of the light sources, so this method is mainly used for low-speed scanning. Another disadvantage is that the device becomes complicated due to the large number of light sources. On the other hand, in the latter method, since a plurality of solid-state R image elements are used, there are problems in adjusting and setting the positions of these elements, and the price is also high. The present invention was made in view of these concerns, and
Its purpose is to enable small, low-cost color image input.
, r ifn Bi human-powered device. (Means for Solving the Problems) The present invention solves the above-mentioned problems by using a color separation filter of 1 in a human-powered image processing device that images a document image at a predetermined magnification of 1.
It is characterized in that it is configured to be changed at least once during scanning. (Function) In the present invention, during one scanning of the color separation filter, less than 4

[Spider 1
I changed the times. (Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is an electrical configuration diagram showing one embodiment of the present invention. In the figure, 11 is a color separation filter that receives optical information from an original (not shown). The color separation filter 1
1 is composed of three types of filters: red (R), green (G), and portrait (B), and these filters are changed at least once during one scan. That is, each of the RlG and B filters is switched at least once during one scan (details will be described later). 12 is a solid-state image element that receives optical information that has passed through the color separation filter 11 and converts it into an electrical signal; 13 is a shading correction circuit that corrects the photoelectric conversion characteristics of the solid m(!Jl element 12; Δ/D
The output of the solid-state image sensor 12 is received via the converter 14 . As the solid-state image sensor 12, for example, a COD is used.
a first line memory storing one scanning line for each color;
A second line memory 6 similarly stores the output of the shading correction circuit 13 for one scanning line for each color. The line memories 15 and 16 each alternately store image data for one scanning line. SW+ and SW2 are changeover switches for switching and supplying image data to these line memories 15 and 16, and specifically, for example, a gate circuit is used. 17 is a color correction circuit that alternately inputs the outputs of the line memories 15 and 16 and performs color correction on each of the three primary color signals @fO; 18 is a color correction circuit that converts the output of the color correction circuit 17 into binary data of 0.1; This is a binarization circuit. As the color correction circuit 17, for example, a ROM containing the color correction calculation results for the input signal as a table is used.
For example, a digital comparator is used. and,
The output of the binarization circuit 18 becomes the output of the device of the present invention,
The data is sent to an external device such as a personal computer. The operation of the device configured as described above will be explained as follows. The original image information enters the color separation filter 11 as optical information. The color separation filter 11 passes only light in a target wavelength range. FIG. 2 is a dimensional diagram showing the characteristics of each filter. In the figure, the horizontal axis represents the wavelength and the Mi axis represents the transmittance. η-0f is for the R filter, 2 is for the G filter,
f3 indicates the characteristics of the B filter. Light passing through the R filter becomes a cyan <C> signal, light passing through the G filter becomes a magenta (M) signal, and light passing through the B filter becomes a yellow (Y) signal. As a result, the three primary color signals R, G, and B of light are converted into the three primary colors C, M, and Y of color. Further, the color separation filter 11 is switched from R filter to G filter to B filter during one scan, and image signal processing is performed for each color. FIGS. 3 to 7 are diagrams showing examples of moving mechanisms for color separation filters. In the embodiment shown in FIG. 3, a belt 21 in which R, G, and B filters 11 are arranged adjacent to each other is rotated in the direction of the arrow in the figure by rotating bodies 22 to 25. A solid-state image sensor 12 is arranged inside the belt 21, and the image information of the original 27 illuminated by the light source 26 is transmitted through a selfoc lens array (SLA) 28 into R, G, B.
The light enters the filter, passes through the R, G, and B filters 11, and enters the solid-state image sensor 12. When the irradiation of one scanning line of the original 27 is completed, the original 27 moves by one scanning line to the next position (in the direction of the arrow in the figure). In the embodiment shown in FIG. 4, the color separation filter 11 is
Attached to the belt 34 rotated by 1 to 33, the belt 3
A light source 26 is arranged inside a triangle 4. light source 2
The emitted light 6 passes through the color separation filter 11 attached to the belt 34 and illuminates the original 27. Reflected light (image information) from the original 27 enters the solid-state image sensor 12 via the SELFOC lens array 28 . By rotating the belt 34, the color separation filter 11 can be changed to R-+G-+B. The embodiment shown in FIG. 5 is a SELFOC lens array 2B.
After passing through the color separation filter 11, the light is applied to the solid-state image sensor 12. In the embodiment shown in FIG. 6, a document 27 is irradiated with light emitted from a light source 26, and the reflected light is applied to a color separation filter 11. The light that has passed through the color separation filter 11 enters the solid-state image sensor 12 via the SELFOC lens array 28 . In both of the embodiments shown in FIGS. 5 and 6, the color separation filter 11 is moved in the direction of the arrow in the figure (horizontal direction). The embodiment shown in FIG. 7 has the same configuration as the embodiment shown in FIG. 4, except that the color separation filter 11 has an arc shape and can be moved in the circumferential direction. different. FIG. 8 is a diagram showing a specific example of the configuration of the color separation filter 11 used in the present invention. As shown in the figure, after the N filter, R, G, and B filters are repeatedly arranged. The N filter is used when a monochrome bottle type is used. FIG. 9 is a diagram showing an example of the drive #I mechanism of the color separation filter 11. (
In the embodiment shown in (a), a hole for a sprocket is formed around the color separation filter 11, and the sprocket is engaged with a sprocket 42 rotated by a motor 41 to perform rotational movement. As the motor 41, for example, a stepping motor is used. On the other hand, in the embodiment shown in (B), an elastic member (for example, a spring) 43 is attached to one end of the color separation filter 11, a cam 44 is brought into contact with the other end, and the cam 44 is rotated in the direction of the arrow to perform horizontal movement. Returning to the explanation of FIG. 1 again, the light that has passed through the color separation filter 11 enters the solid-state image sensor 12 and is converted into an electrical signal. is converted into digital data (image data) and subjected to level correction for each pixel by the shading correction circuit 13.This digital data is first transferred to the line memory (image data) of the first line memory 15 via the changeover switch SW1. One line of image data is stored in R).Next, the color separation filter 11 switches to G, and one line of image data is stored in the line memory (G).Next, the color separation filter 11 switches from G to B, and one line of image data is stored in the line memory <8). In this way, when one line of R, G, B33 original image data is stored in the first line memory 15, the changeover switch is changed from the SW 1 side to the S W 1 side.
The image data is switched to the W2 side, and one line of image data is stored in the second line memory 16 in the same manner. During this time, the image data stored in the first line memory 15 is read out for each primary color and subjected to color correction in the color correction circuit 17. It is output to an external device.The binarization circuit 18 includes:
A threshold value is not given in advance depending on whether the original image is a gradation image or a line drawing, and human image data is binarized using this threshold value as a reference value. The binarized image data is transferred to an external device such as a personal computer. The transferred image data is then displayed on a CRT or printed by a printer. FIG. 10 shows the operation of the device of the present invention and does not show timing chart 1.
It's to. In the figure, (a) is R, G. The marker signal output for each Bffi processing, (b) shows the processing state of the image signal, and (c) shows the motor drive signal. The motor drive signal (c) is at the "°1" level on and the "0" level is on. First, turn on the motor, move the document by one scanning line, and move the document during one scanning period. , performs R, G, and B signal processing as shown in (0).T1 in the figure indicates the accumulation time of R4M@light, and T2 indicates the image processing time of the R signal. In the explanation, we will use 2 as the final image data.
Although nitrified 21ifl data was used, it is not limited to binary data, and other data may be used. , %-Shi-n (y is not necessarily the same as that of Haku IJ, I,. (Effect of the invention) In detail: For example, each of the color separation filters [).J6 is configured to change the G and B filters at least once during one scan.
j] It is possible to realize an image input device that can input color image information. According to the present invention, since a method is adopted in which each of the three primary colors is separated using a color separation filter, it is possible to realize a device having a compact structure in a cylinder and therefore being inexpensive.

[Brief explanation of drawings]

FIG. 1 is an electrical configuration diagram showing a fourth embodiment of the present invention, FIG. 2 is a diagram showing the characteristics of a color separation filter, and FIGS. 3 to 7 are diagrams showing examples of a moving mechanism of the color separation filter. FIG. 8 is a diagram showing a specific configuration example of a color separation filter, FIG. 9 is a diagram showing an example of a drive mechanism of the color separation filter, and FIG. 10 is a diagram showing the operation of the apparatus of the present invention. The figure shows an example of a conventional device. 1.27... Original 2... Red/'Green LED 3
・-・Blue fluorescent panel 4...Selfoc lens 5
...Photoelectric conversion cable 6...Drive circuit 11...
- Color separation filter 12...solid-state image sensor 13...shading correction circuit 14...A/D converter 15.16...line memory 17...color correction circuit 18...binarization circuit 21.
34...Belt 22-25.31-33...Rotating body 26...Light source 28...Selfoc lens array 41...Motor 42...Sprocket 43
...Elastic member 44...Cam SWI, SW2・
...Changeover switch patent applicant Roku Konishi Photo Industry Co., Ltd. Representative Patent attorney Fuji Tsukishima 1 person

Claims (3)

[Claims] (1) An image input device for capturing a document image at a predetermined magnification, characterized in that the image input device is configured to change a color separation filter at least once during one scan. (2) The image input device according to claim 1, wherein the color separation filter is moved perpendicularly to the main scanning direction of the original image. (3) The color separation filter is rotatable, and at least one of a light source, a photographing optical system, an image sensor, and a document placement and transportation member is provided.
An image input device according to claim 1, characterized in that the image input device is provided in a.