JPS5840973A - Optical information reader - Google Patents

Abstract

PURPOSE:To obtain a uniform output of photodetection, by providing a light shielding matter to a light receiver to unify the received light volume of a photodetector. CONSTITUTION:The light is irradiated to the reading part of an original 1 from a linear light source 2, and this reflected light is condensed through an optical system 3 and received at a solidstate scanning part 4 serving as a light receiver to undrego a photoelectric conversion, a reading scan, etc. The part 4 is formed by having a 1-dimensional array of solid-state image pickup elements 5. A belt- shaped light shielding matter 6 is vapor deposited on the light receiving surface of each element 5. The matter 6 controls the light receiving volume of the element 5. Thus the receiving light volume is unified for each element 5 regardless of its position.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical information reading device that can correct uneven light reception with a simple configuration.

For example, in an optical information reading device used as a reading scanning section of a 7AxT9 device, the emitted light intensity at the position in the length direction of a linear light source of fluorescent lantern is independent, and the received light intensity of the light receiver is controlled by a lens or the like. may be uneven depending on the position. Therefore, in the past, a light source whose light emitting characteristics were uniformized positionally through special processing was used, or the light source was adjusted by adjusting the light transmitting material installed in the optical system such as the light source and lens. This made it possible to make the received light intensity uniform.

However, with this method, the light source is specialized and general mass-produced products cannot be used, making it expensive, and the adjustment of the optical system is complex, requiring time and effort. Productivity was extremely low due to the complex configuration.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to eliminate the need for special light sources and optical system adjustments, uniformize the received light output with a simple configuration, and improve productivity. The object of the present invention is to provide a high-quality and inexpensive optical information reading device.

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a schematic configuration diagram of an optical information reading device in the same embodiment, and the device irradiates light from a linear light source 2 onto the reading section of a document 1 as a medium to be read and failed, which is set on a reading stand (not shown). The reflected light is collected by an optical system 3, received by a solid-state scanning section 4 serving as a light receiver, and subjected to photoelectric conversion, reading scanning, etc. Here, the solid-state scanning section 4 is a one-dimensional array of a plurality of solid-state imaging devices.

Now, as shown in FIG. 2, strip-shaped light shielding bodies 6 are provided on the light-receiving surfaces of these solid-state image sensors 5 by means such as vapor deposition or printing. These light shielding bodies 6 adjust the amount of light received by each solid-state image sensor 5 for each element to make it uniform regardless of its arrangement position, and have different light shielding widths.

This light-shielding width is set according to the received light intensity characteristics when the reflected light from a blank original is received.For example, when the received light intensity characteristics are as shown in
The width is gradually decreased as it approaches the center of the array.

Therefore, if the above-mentioned six widths are appropriately determined by measuring or calculating the received light intensity, the received light intensity characteristics of each solid-state image sensor 5 can be made uniform as shown in FIG. 3.

As described above, the present embodiment has an extremely simple configuration in which the light shielding body 6 whose light shielding width is varied according to the received light intensity characteristic Φ of each solid-state image sensor 5 is provided on the light-receiving surface of each solid-state image sensor 5. In this way, uneven light reception (shading) can be corrected. Therefore, using a special light source as in the past,
Since a complicated adjustment mechanism of the optical system and its adjustment are not required, productivity can be increased and it can be provided at low cost.

Note that the present invention is not limited to the above embodiments.
For example, in the above embodiment, a light shielding body 6 is provided for each solid-state image sensor 5, but a transparent light-transmitting sheet on which the light shielding portions are printed or written at the same spacing as the arrangement spacing of each element 5 may be provided. As a result, the light shielding body 60
A light shielding body having a mouth portion) may be used for a solid-state image sensor,
In the case of H, the slit ring is large, so it is sufficient to install a light shielding body on each element JK on both ends, and a light shielding body with a small - on each element 5 in the center.Furthermore, as shown in 44. The translucent layer 11y may be multi-layered according to the received light intensity characteristics, thereby making the received light intensity uniform.Also, as another embodiment of the present invention, the light receiving surface of each solid-state image sensor may be partially layered. Redetri! Alternatively, the grain activation (making it more sensitive to light) may be used to reduce the light-receiving area of each element to adjust the light-receiving sensitivity and equalize the light-receiving output. In general, the solid-state image sensor in a 7-piece comb device is often manufactured as an element exclusively for each model, so the above-mentioned inactivation process or By adding the step of forming the light shield in the above embodiment, it can be manufactured efficiently without any additional special processing, and it is extremely simple and inexpensive compared to the case where special processing is applied to the light source. There are advantages that can be realized. In addition to the reading unit of a facsimile machine, it may also be applied to an OCR system.Furthermore, in the case of a facsimile machine, it can be applied to a so-called contact type reading device in which the light receiver is brought into direct contact with the document to read the document. In this case, if a light shielding member is used, it also functions as a maintenance member for the solid-state image sensor, so there is no need to use a protective member.In addition, the configuration and type of the light receiver and light receiving element, etc. Various modifications may be made without departing from the spirit of the present invention.

As detailed above, the light receiving output of each element can be made uniform by providing a light shield on the light receiver to equalize the amount of light received by each light receiving element, or by processing each light receiving element to adjust the light receiving sensitivity. According to the present invention, there is provided an optical information reading device that does not require special light sources or optical system adjustments, can uniformize the received light output with a simple configuration, and is highly productive and inexpensive.

The neck can be provided.

[Brief Description of the Drawings] Figures 1 to 3 show one embodiment of the present invention.
The figure is a schematic adjustment diagram of the optical information reading device, Figure 2 is a diagram showing the main parts of the device, the third diagram shows the received light intensity characteristics, and Figure 4 shows another embodiment of the present invention. It is a sectional view of the main part. 1... Original, 2... Linear light source, 3... Optical system, 4
. . . Solid-state scanning unit, 5. Solid-state imaging device, 6. Light shielding body, 1. Semi-transparent film. Applicant's agent Patent attorney Takeshi Suzue Hikoga 1

Claims (2)

[Claims] (1) In an optical information reading device in which light is irradiated onto a medium to be read and the reflected light is received by a light receiver equipped with a plurality of light receiving elements, the light receiver is equipped with a transparent film that equalizes the amount of light received by each light receiving element. An optical information reading device characterized in that a light body is provided closely to a light receiving element. (2) In an optical information reading device that irradiates light onto a medium to be read and receives the reflected light with a light receiver equipped with a plurality of light receiving elements, the light receiving sensitivity of each light receiving element in the light receiving section is determined. What is claimed is: 1. An optical information reading device characterized in that a process is performed to adjust the amount of light to form a partial inactive portion so that the light receiving output of each light receiving element is made uniform.