JPS60210061A - Color picture reader - Google Patents

Abstract

PURPOSE:To read simply color pictures with high accuracy by transmitting the light formed into an image through a lens to a photoelectric transducer through a 3-layer optical fiber having larger width than an original. CONSTITUTION:The beams given from fluorescent lamps 3a and 3b are reflected by an original 2, and these reflected beams are reflected successively by plane mirrors 4a-4c and led to a lens 5. An optical fiber focusing spectroscope 13 is provided so that an end of this spectroscope is set at an image forming position of the original 2 by means of the lens 5. The spectroscope 13 has a condensing surface 14 and the reflected beam is separated into the light every layer through 3-layer optical fibers 16a-16c having larger width than the original 2. This separated light is separated into three primary colors through optical filters 8a-8c which transmit three primary colors and transmitted to photoelectric transducer trains 9a-9c. Then the color gradations are converted into electric signals. Thus, color pictures are read satisfactorily with a simple optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an image reading device, and particularly to an image reading device that can read color images using a simple optical system.

[Background of the invention]

Conventional color image reading devices separate the image into three primary colors, such as red, green, blue, or yellow, cyan, and magenta, for each pixel, which is a tiny dot that divides the image, and then generates photoelectric signals corresponding to each of the three primary colors. A photoelectric conversion sensor consisting of an array of conversion elements converts the shading of each color of light into an electrical signal. FIG. 1 shows an example of a conventional color image reading device.

A document 2 on a glass document table 1 is irradiated with light from fluorescent lamps 3a and 3b provided at the bottom of the document table 1, and the reflected light from the document 2 is reflected by three plane mirrors 4a and 4b.

4c, the light is sequentially reflected and guided to a lens 5, and the lens 5 condenses the light into two half mirrors 5a.

6b, the light reflected from half mirror 6a, the light transmitted through half mirrors 6a and 6b, and 4, half mirror 6.
The three light beams including the light reflected from the light source b are separated into three primary color lights, and each of these separated primary color lights is sent to three photoelectric conversion sensors 7a and 7b, respectively.

The photoelectric conversion element array on 7C converts it into an electrical signal. The color image reading device constructed in this manner has a drawback that the optical system is complicated and requires skill to assemble. In order to improve this drawback, a photoelectric conversion sensor as shown in FIG. 2 was proposed. Three photoelectric conversion element arrays 9a, 9b, 9c each having an optical filter 8a, 8b, 8c arranged on the front surface that transmits light of three different primary colors are arranged in a ceramic package 10, and a protective glass is placed on the front surface of the arrays. 11, and electrical signals after photoelectric conversion are taken out from terminal pins 12 connected to each photoelectric conversion element. FIG. 3 schematically shows an optical system of a color image reading device using the photoelectric conversion sensor shown in FIG. 2. Three photoelectric conversion element rows 9a.

The light that enters each of 9b and 9c through the lens 5 passes through the path shown by the dashed lines a, b, and C shown on the document 2, as well as the broken line. Therefore, when performing color tone correction of an image on the same line, for example, an image on the a line, the a line comes to the position of the b line or the C line, and one of the three different primary colors is read by the photoelectric conversion elements 9b and 9c. It is necessary to store up to 1000, and a memory for read signals is required. For example, J.I.
When reading an S standard B4 size original (256 mm width) with a precision of 8 lines/mm, the photoelectric conversion element array is composed of 2048 photoelectric conversion elements, but the element pitch is 10 μm and the photoelectric conversion element array is If it is arranged for each lInl11, 1 mm corresponds to 100 reading lines, so if the photoelectric conversion element row 8a at one end is used as a reference, 1 mm worth of reading lines for the photoelectric conversion element row 8b in the center. 2048 x 100 = 204,800 data memories corresponding to 100 lines are required, and 2048 x 200 = 409,600 pieces corresponding to 200 2 mm reading lines are required for the photoelectric conversion element row 8c at the other end. Data memory is required. Therefore, since a total of 614,400 data memories are used for the photoelectric conversion element arrays 8b and 8c, if 8 bits are used per data, a memory of 4915,200 bits is required, which is 25
Even if a 6 kbit RAM was used, 20 RAMs would have to be used.

[Purpose of the invention]

The present invention has been made in view of the above points, and its purpose is to provide a color image reading device that can read good color images with a simple optical system without using extra electronic components. There is something to do.

[Summary of the invention]

The present invention uses a photoelectric conversion sensor that integrates three layers of photoelectric conversion elements each provided with three rows of optical filters for condensing reflected light from the mi surface with a lens and separating it into three primary colors.
In a color image reading device equipped with an optical system that converts the shading of each color divided into three primary colors into electrical signals, the lens forms an image of the light, and from this imaging position, the light is transmitted to the photoelectric conversion element array in the photoelectric conversion sensor. The intended purpose is achieved by using, as a transmission means, an optical fiber formed in [1] above the middle part of the original and converged into three layers.

[Embodiments of the invention]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a color image reading device according to the present invention will be described below with reference to the drawings.

An embodiment of the present invention is shown in FIGS. 4 and 5.

In this figure, parts that are the same as those of the conventional example shown in FIGS. 1 to 3 are indicated by the same symbols. As in the conventional example, at the bottom of the document table 1 on which the document 2 is placed, there are two fluorescent lamps 3a and 3b that illuminate the document 2, and three fluorescent lamps that sequentially reflect the light irradiated onto the document 2. plane mirror 4a.

4b, 4c, and a lens 5 that focuses the reflected light. An optical fiber focusing spectrometer 13 is provided so that one end thereof is located at the position where the original 2 is imaged by the lens 5.
Optical fibers 16a, 1 with minute diameters are laminated in three layers on the light condensing surface 14 and separated into layers on the photoelectric conversion element row surfaces 15a, 15b, 15c on the reflection side.
6 b.

16c is provided. The photoelectric transformer-j row plane of these optical fibers separated into layers, 15a.

Optical filters 8a are provided in 15b and 15c, respectively.

Photoelectric conversion element arrays 9a, 9b via 8b, 8c.

9c is connected to the photoelectric conversion element arrays 9a and 9b, which separate the reflected light from the document 2 into three primary colors.

9c. Further, a light shielding wall 17 is provided around the opening of the optical fiber condenser 13 on the lens 5 side.
covered by. Furthermore, the three-layered optical fibers 16a and 16b.

ItJ of 16c is formed so as to exceed image rlJ.

According to one embodiment of the present invention configured as described above, the light from the fluorescent pairs 3a and 3b is reflected by the original 2, and this reflected light is sequentially reflected by the planes fi4a, 4b, and 4c, and then reaches the lens 5. A three-layer optical fiber 16 is guided and has a converging surface 14 at a position where the image of the original 7 is formed by this lens 4.
a, 16 b.

16e, the reflected light is separated into layers of light, and an optical filter 8a transmits three different primary color lights;
The light is separated into three primary colors by 8b and 8c, and transmitted to photoelectric conversion element arrays 9a, 9b, and 9c, where the color shading is converted into an electrical signal. At this time, since the diameter of the optical fiber is several to several tens of micrometers, the deviation of the images received by the three photoelectric conversion element arrays is also about the same, and almost the same light spots of the images are arranged at 0 intervals from each other. Each photoelectric conversion element row 9a, 9b of the row.

9c, and the amount of electronic components such as RAM required to correct the reading position of each photoelectric conversion element array can be significantly reduced.

In this embodiment, there are three photoelectric conversion element rows 9a and 9b.

Although a case has been described in which a photoelectric conversion sensor having an integrated photoelectric conversion element 9c is used, it goes without saying that the same effect can be obtained even if three photoelectric conversion sensors each having only one photoelectric conversion element array are used. However, in this case, the spacing between the photoelectric conversion element rows increases significantly and it is difficult to form each photoelectric conversion element row on the same plane. Optical connections tend to be insufficient, making it impractical.

〔Effect of the invention〕

As described above, according to the present invention, the reflected light from the document of the color image reading device is divided into minute diameters. Since the light is received from the light-receiving surface of three layers of optical fibers and transmitted through the optical fiber to the photoelectric conversion element array surface separated one layer at a time, the shift in the reading position of each photoelectric conversion element can be avoided. The amount of electronic components required for correction can be significantly reduced, and the effect of being able to provide a color image reading device that is easy to assemble with a simple optical system, is inexpensive, and has high reading accuracy is significant.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing the configuration of a conventional color image reading device, Fig. 2 is a perspective view showing a photoelectric conversion sensor according to the conventional technology, and Fig. 3 is an optical system using the photoelectric conversion sensor shown in Fig. 2. FIG. 4 is a vertical sectional view showing the configuration of an embodiment of the color image reading device according to the present invention, and FIG. 5 is a perspective view showing details of the optical fiber focusing spectrometer shown in FIG. 4. It is. DESCRIPTION OF SYMBOLS 1... Original table, 2... Original, 3a, 3b... Fluorescent pair, 4a, 4b, 4c... Plane mirror, 5... Lens,
6a. 6b... Half mirror 17a + 7 b e 7
c... Photoelectric conversion sensor, 8 a, 8 b, 8 c
- light filter, 9a. 9b, 9c...Photoelectric conversion element array, 13...Optical fiber focusing spectrometer, 14...Condensing surface, 15a, 15b. 15c-Photoelectric conversion element row surface, 16a, 16b. 16c...Optical fiber. 1 figure, 2 figures, 3 figures

Claims (1)

[Scope of Claims] 1. A photoelectric converter consisting of a three-layer photoelectric conversion element each provided with three-layer optical filters for condensing light reflected from the surface of a document irradiated by a light source with a lens and separating the light into three primary colors. In a color image reading device equipped with an optical system that transmits the light and light of each color separated into three primary colors by the photoelectric conversion sensor to an electrical signal, the light imaged by the lens is transmitted from this imaging position. As a means for transmitting data to the photoelectric conversion element in the photoelectric conversion sensor,
A color image reading device characterized by using an optical fiber formed in a J shape and converged into three layers. 2. The optical fiber has one converged end as a light condensing surface, and the side opposite to the converging surface is separated into layers and connected to the photoelectric conversion element array. The color image reading device described above.