JPS59143466A - Photoelectric conversion device - Google Patents

Abstract

PURPOSE:To simplify an optical lens system and to make a photoelectric conversion device in small size by using a large-sized image sensor having almost the same width as that of an original and photoelectrically converting the original so that the image sensor is almost closely contact to the original. CONSTITUTION:The original 201 is illuminated by a fluorescent lamp 102 and reflected light from the original 201 is guided to the image sensor 203 by a fiber lens array 202 as an optical lens system. The original 201 is carried by a driving roller 204. The image sensor 203 is formed so as to have the width almost the same as that of the original 201 as the three rows of photodiode strings 302 formed on a glass base plate 301 at a prescribed pitch. In addition, red, green and blue filters 303-305 are formed on respective diode strings 302. Thus, the optical lens system for the photoelectric conversion device is simplified and a real image of unmagnification to the original 201 is formed on the image sensor 203.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoelectric conversion device for reading color originals, and particularly to a device that is miniaturized.

Conventionally, there was a device shown in Figure 1 as this divine device.

In the figure, (101) is a document drum, (102) is a fluorescent lamp, (103) is an id lens, and (104a) is a (1)
04b) is half mirror-1 (105X106) and (
107) are red filters.

Green filter and blue filter p, (108
) is a photoelectric conversion element that has almost flat sensitivity in the visible light region.

Next, the operation will be explained. Cylindrical drum (lOl)
The manuscript that was removed was exposed to a white light source, a fluorescent lamp (102
), and the reflected light is divided into three parts by a lens (103) and a half mirror (1o+aXxo4b). The divided lights are each passed through a red filter (105
), a green filter (106), and a blue filter (107) before being guided to a photoelectric conversion element (108).

As described above, the color information on the original is separated into three primary colors and converted into a blur signal by the photoelectric conversion element (108).

Since the conventional photoelectric conversion device for reading color originals is constructed as described above, it has the following drawbacks.

(1) Lens (103), bar 7 mirror (1oa
Unless an optical system such as a) Qo4b) is used, the distance from the original drum (101) to the photoelectric conversion element (108) t is several tens of σ, making it impossible to downsize the apparatus.

(2) Since the optical path is divided into three parts by the half mirrors (104a) and (104b), alignment is required for each optical path, which makes the mechanism complicated, and color shift due to poor adjustment is likely to occur.

This invention was made in order to simultaneously eliminate the two drawbacks of conventional devices such as those mentioned above.It uses a large image sensor with a width that is almost the same as the width of the original, and uses a large image sensor that is in close contact with the original to perform photoelectric conversion. By doing so, the purpose is to provide a small and simple photoelectric conversion device for color reading.

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.
The figure is a sectional view of a photoelectric conversion device according to an embodiment of the present invention. In the figure, (201) is an original, (102 is a fluorescent lamp for illuminating this original (201), and (202) 14
A fiber lens array is used as an optical lens system to guide reflected light from the original (201), (203) is an image sensor, and (204) is a drive roller for conveying the original (201).

FIG. 3 is a perspective view showing a part of the image sensor (203). sb, (3
03), (304) and (305) are red filters formed above the photodiodes (302) in each column, respectively.

They are a green filter and a blue filter.

FIG. 4 is a cross-sectional view taken along the line A-A in FIG.
) and a transparent % pole (403), and a red filter (303) and a green filter (30) are applied to the soil.
4) and a blue fill (305) are formed, respectively.

Next, the operation will be explained. The manuscript (201) was lit under a fluorescent light (
102). Image sensor (203)
is separated from the document surface by about 20 to 50 degrees, and the images of the B and YA document surfaces are focused on the image sensor (203) as real images at the same magnification by the fine lens array (202). As shown in FIG. 3, the image sensor (20,j) has 1728 photodiodes (302) in 3 rows at a pitch of 125 μm, totaling 51841111!
I have been placed. These photodiodes (302
) is arranged at a pitch of 130 μm in the column direction. Furthermore, on the soil of the valley photodiode (302), there are rows of red, green,
Blue gelatin filters (303), (304), (3
05), color-separated image signals are obtained from each column of photodiode arrays. and 1
When the photoelectric conversion for the third time is completed, the original (201) is advanced by 136 μm along the drive line ′τ, ], and the same photoelectric conversion as the −th time is performed. By doing so, color reading of letterized (210 mm width) original image 11 can be realized with a resolution of 8 dots in the main scanning direction/7.7 dots in the sub-scanning direction.

2f;, the chain made in the example is configured as described above, and when scanning the 14th line (i-2), the red component of line [1, (
i-1) Since the storage and components of the first line and the evening component of the first line can be easily stored, it is recommended to have a buffer memory for at least three lines of each color in the control circuit. De:
111 (1 image signal) can be separated into each color component and outputted.

To δ et al.? Since the optical path is not divided as in the I←X example, alignment is easy and color blurring hardly occurs.

In the above embodiment, a 7゛ amorphous silicon photodiode array was used as the optical element, but polycrystalline silicon + 46 mm was used as the material.
Iij+Silicon r Ga A b + L d S
+ L d'le 4) may be used, and light guides and elements made of similar materials may also be used.

Figure 2 Figure 3

Claims (4)

[Claims] (1) A white light source for illuminating the original, an optical lens system that guides the reflected light from the original to an image sensor (to be described later), and a large number of optical lenses having a width that is almost the same as the width of the original and arranged in a straight line in the width direction. A photoelectric conversion element array including photoelectric conversion elements is arranged in double rows, and includes a nuclear sensor, and the image sensor is arranged close to the original document with the optical lens thread interposed between the photoelectric conversion elements. BuC electric conversion device. (2) The above optical lens system is a fiber lens array f
2. The photoelectric conversion device according to claim 1, wherein the photoelectric conversion device is configured to form an image on the sensor substrate surface at the same magnification as the original surface. (3) The photoelectric conversion device according to claim 1 or 2, characterized in that three rows of the photoelectric conversion elements are arranged. (4) The photoelectric conversion device according to claim 3, wherein the filters having the specific spectral transmittance characteristics are red, green, and blue filters, respectively.