JPS59135761A - Photoelectric conversion reading device - Google Patents

Abstract

PURPOSE:To compact the titled device and reduct cost by constituting a manuscript reading system by using a half mirror. CONSTITUTION:A half mirror 34 employing the joining surface of two prisms as a half mirror section is used, and a light source 32 for illumination is set up on one surface of the half mirror and a photoelectric conversion element 33 on the other surface. A manuscript 31 is arranged on one surface opposite to the conversion element 33, and a reading system consisting of the half mirror 34, the light source 32 and the conversion element 33 is constituted so that the manuscript is read by moving the manuscript 31 or the reading system. Beams from the light source 32 are bent in the direction of the manuscript 31 by the half mirror 34 first. Bent beams collide with the manuscript 31 and are reflected, and transmit the half mirror 34 and reach to the conversion element 33. The diffusion of beams from the light source and reflected beams from the manuscript can be inhibited by setting up a cylindrical lens and a reticular lens between both the light source 32 and the half mirror 34 and both the half mirror 34 and the conversion element 33.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoelectric conversion reading device, and more particularly to an optical 71Σ conversion reading device that can be applied to facsimiles, digital copiers, barcodes, etc.

Conventionally, in a document reading system such as a facsimile machine, a document 11 is uniformly illuminated by an illumination light source 12 such as a fluorescent lamp, and the reflected light is reflected by a lens 13 or the like, as shown in the schematic overall perspective view of FIG. An image is formed on the photoelectric conversion element 14 using an optical system to obtain a time-series electric signal. Assuming that the photoelectric conversion element 14 used here is a chip with a size of about 20iic manufactured by IC technology such as MOS or COD, the document 11 is A4 size (210s
+mx297), it is necessary to reduce the original 11 to about one-tenth using the lens 13. Therefore, when a small-sized photoelectric conversion element is used for an original, the distance from the original to the photoelectric conversion element must be considerably increased in order to reduce the size of the original. Unfortunately, the problem of increasing the size of the apparatus and the reduction of the document by the lens system caused problems of lens aberrations such as distortion of the i-document.

Furthermore, if an attempt is made to manufacture a device that solves the above problems, it will require the use of expensive lenses, and the adjustment of the optical system will become difficult, resulting in problems in terms of cost.

As a means to solve the above-mentioned problems, for example, an elongated photoelectric conversion element and a cell-hoc lens array (5elfoc lens array) are proposed.
M+: fA and 9′
A device having a 1:1 correspondence with the turtle conversion element has been proposed. This is a configuration as shown in the schematic overall perspective view of FIG. In Figure 2, 21B) breath + height, 22
2 is a cell-hock lens array, and 26 is a photoelectric conversion element. Although such an apparatus is advantageous in eliminating lens aberrations and making the reading p system more compact, it does not solve the problem of high cost because it uses a cell-hoc lens array. Furthermore, since a Cell-Hoc lens array is used in the optical system, the thickness of the entire reading system depends on the length of the Cell-Hock lens, and there is a problem in that there is a limit to how much the reading system can be made more compact in the thickness direction. remains.

An object of the present invention is to provide a thin contact type photoelectric conversion/reading device that does not use an optical system (imaging lens) that causes the above-mentioned problems.

The photoelectric conversion/reading device of the present invention includes an illumination light source, a photoelectric conversion element, and a half mirror, and the light from the illumination light source is bent by the half mirror, reaches a document, etc., and is reflected.
The structure is such that the reflected light passes through a half mirror and reaches the photoelectric conversion device.

In the above, the term "manuscript, etc." refers not only to what is commonly called a manuscript in which characters or images are recorded on a recording material such as paper, but also to what is commonly called a manuscript, such as barcode reading, OCR, mark sheet, etc. Although it is not generally called a manuscript, it goes without saying that it includes any document whose characters, images, symbols, etc. can be read by photoelectric conversion.

Hereinafter, the present invention will be explained using figures.

FIG. 6(-1) and FIG. 5(b) are diagrams showing one preferred embodiment of the present invention, FIG. 3(-) is a schematic overall perspective view, and FIG. 6(b) is a diagram showing a preferred embodiment of the present invention. It is a schematic cross-sectional partial view taken along the dashed line XX/ in FIG. 3(a).

In FIG. 6(-) and FIG. 6(b), 61 is a manuscript;
32 is a light source for illumination, 66 is a photoelectric conversion element, and 64 is a half mirror. As shown in both figures, this embodiment example has 2
1. Using a half mirror 64 in which the joining direction of two prisms is a part of a half mirror. (An illumination light source 62 is provided on one side of the half mirror 34, and a photoelectric conversion element 33' is provided on the other side of the half mirror 34. half mirror
54, and by moving the original 61 or the reading system consisting of the illumination light source 62, the photoelectric conversion element 55, and the half mirror 34, the
C-taking is done.

Light from the illumination light source 32 is first bent toward the original 61 by the half mirror 34 .

The bent light hits the original 61, and an amount of reflected light corresponding to the reflectance of each part of the original 51 is reflected on the half mirror 34. Part of the reflected light is reflected by the half mirror 34, and the remaining part is reflected by the half mirror! +4 is transmitted (7 and reaches the photoelectric conversion element 66. The photoelectric conversion element 36 performs photoelectric conversion according to the incident light and converts the light into an electrical signal.

In this embodiment, the resolution of original reading is determined by the density of photoelectric conversion units of the photoelectric conversion element 53. However, if the distance from the original 31 to the photoelectric conversion element 35i is large, the reflected light from the original 31 will overlap, resulting in a decrease in resolution. Furthermore, if the distance is abnormally large, it becomes impossible to read the original 61 itself. Therefore, the distance from the original fA 31 to the photoelectric conversion element 33 is appropriately determined depending on the resolution of the document reading system.

In the present invention, since the original reading υ thread is made of half honey, it is undeniable that the amount of light of the optical signal incident on the photoelectric conversion device is attenuated. Therefore, depending on the arrangement and light intensity of the illumination light source, a reduction in reading speed or resolution may occur due to an insufficient amount of light incident on the photoelectric conversion element.

FIG. 4 is a schematic perspective view showing a reading υ thread according to another embodiment of the present invention. In the figure, 41 is a light source for illumination, 42
43 is a half mirror, 144 is a cylindrical lens, and 45 is a lenticular lens.

This embodiment example has the same basic configuration as the previous embodiment example, but includes an illumination light source 41 and a half mirror 46.
There is a cylindrical lens 44 between the two, and a half mirror 4.
Lenticular lens 45 between 6 and photoelectric conversion element 420
What is different is that they are set up differently.

In this way, by placing lenses on the light source side and the photoelectric conversion element side, it is possible to suppress the diffusion of the light from the light source and the light reflected from the document, so the amount of light for illumination can be reduced. The same effect can be obtained by increasing Therefore, the problems of reduced reading speed and resolution that may occur in the embodiments shown in FIGS. 6(a) and 6(b) can be avoided. In this case, the same effect can be obtained even if a lenticular lens is arranged instead of the cylindrical lens 44 on the illumination light source 41 side, or if the lenticular lens 45 on the photoelectric conversion element 42 side is replaced with a cylindrical lens.

Furthermore, the cylindrical lens 44 can be replaced by making the prism portion constituting the nof mirror on the side of the illumination light source 41 convex. Furthermore, only one of these two lenses may be disposed. Note that the lenticular lens 45 is the photoelectric conversion element 4
It is formed to correspond to two photoelectric conversion units.

In the above two embodiments, the half mirror is formed by making the joining surface of the two prisms a part of the half mirror, but it can also be produced in exactly the same way using a plate-shaped half mirror. can.

Furthermore, it goes without saying that any light source may be used as the illumination light source in view of the spectral sensitivity distribution of the photoelectric conversion element, as long as it can irradiate the necessary portions of the document sufficiently and evenly.

As described above, the photoelectric conversion/reading device of the present invention allows for much easier optical adjustment than conventional devices, making the device easier to manufacture and very advantageous in terms of cost. . In addition, especially when a type of half mirror in which two prisms are joined is used, the illumination light source, photoelectric conversion element, or lens can be installed on the prism, making assembly of the device even easier. become.

The photoelectric conversion/reading device of the present invention has the following features compared to conventional ones:
It is compact and does not require expensive lenses or precise optical adjustments, resulting in a lower cost device. Furthermore, since there is no need to reduce the size of the document using a lens, the design of the apparatus becomes very simple.

[Brief explanation of the drawing]

1 and 2 are schematic overall perspective views for explaining a conventional photoelectric conversion/reading device, respectively, FIG. 6(a) is a schematic overall perspective view for explaining an embodiment of the present invention, Figure 6 (b
) is a schematic sectional view taken along the dashed line xx' shown in FIG. 5(a), and FIG. 4 is a diagram for explaining another embodiment of the present invention. 11.21.31...Original 12...Illumination light source 13...Lens 14.23, 33.42...Photoelectric conversion element 22/Self-cell hook lens array 52.41...Illumination light source 44 ...Cylindrical lens 45...Lenticular lens Applicant: Gyanon Co., Ltd. No. 3v (0,) (b) Continued from page 1 @ Inventor: Takashi Noma No. 3-30-2, Shimomaru r, Ota-ku, Tokyo Canon Co., Ltd. Inside the company @ Inventor Mitsunobu Nakazawa Inside Canon Co., Ltd., 3r-30-2, Shimomaruko, Ota-ku, Tokyo

Claims (1)

[Claims] An illumination light source, a photoelectric conversion element, and a half mirror are arranged.The light from the illumination light source is bent by the half mirror, reaches the document, etc., and is reflected.The reflected light passes through the half mirror and reaches the photoelectric conversion device. A photoelectric conversion/reading device characterized by having a structure that allows the reader to reach the target.