JPH029261A - Complete contact sensor - Google Patents

Abstract

PURPOSE:To attain a complete contact sensor offering ease of assembly and ensuring an optical path length inexpensively by mounting a plastic film formed with a thickness ensuring the reflected optical line length from an original onto a sensor base. CONSTITUTION:The sensor is provided with a sensor base 1 to a mount base 2, a light source 3 radiating light 11 from the rear side of the sensor base 1, an IC cover 4 covering a sensor drive IC 5 mounted on the surface of the base 1 and a polyester film 7 formed so as to cover the surface of the sensor base 1 while taking the other end as a free end whose one end is adhered to the IC cover 4 by an adhesivers. When the rear side of the sensor base 1 is irradiated with the light 11 from the light source 3, the light 11 reaches the original 6 through the polyester film 7 and the sensor base 1. When the original 6 is white, the light 11 is reflected and transmits through the polyester film 7 and made incident in a photoelectric conversion element 12 formed on the sensor base 1.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a so-called complete contact type sensor that does not use a condensing lens, and particularly relates to a complete contact type sensor suitable for easily securing an optical path length. .

[Conventional technology]

A conventional fully contact type sensor is, for example, disclosed in Japanese Patent Application Laid-Open No. 61-24
As described in Japanese Patent No. 8655, it has been proposed to attach a microsheet glass plate or form a transparent protector on the light receiving element in order to ensure the optical path length.

[Problem to be solved by the invention]

In conventional full-contact sensors, a microsheet glass plate or transparent protector is pasted on the photodetector, so handling must be done to prevent the microsheet glass plate or transparent protector from breaking. Because it is necessary to carefully consider the following factors, it takes many days to produce the product, which is a bottleneck for low prices.

SUMMARY OF THE INVENTION An object of the present invention is to provide a completely contact type sensor that is easy to assemble, is inexpensive, and can easily ensure an optical path length.

[Means for Solving the Problems] In order to achieve the above object, in the fully contact type sensor of the present invention, a plastic film is formed on the sensor substrate to a thickness that can ensure the length of the optical path reflected from the original. It was installed.

The plastic film has a matte finish on the reading pixel side to prevent reflection from the surface.

[Effect]

- A fully contact type sensor configured as shown in F is a plastic film that has excellent properties such as flexibility, low shrinkage, and abrasion resistance, and is formed to a thickness that ensures optical path length and reading resolution. , it is very easy to assemble, and the optical path length can be easily secured at low cost.

Furthermore, since the film is matted in a satin-like manner on the reading pixel side, it is possible to reduce reflection of light on the film surface, thereby stabilizing the reading output.

〔Example〕

1 and 2 showing one embodiment of the present invention will be described below.

As shown in FIG. 1, a sensor board 1 is mounted on a mounting base 2, a light source 3 that emits light 11 from the back side of the sensor board I,
I covers the sensor driving IC 5 mounted on the surface of the substrate 1
It consists of a C cover 4 and a polyester film 7 formed to cover the surface of the sensor substrate 1 with one end fixed to the IC cover 4 with an adhesive or the like and the other end free. Note that 8 in the figure is a platen roller for running the original 6, and I2 is a photoelectric conversion element.

The polyester film 7 is formed to have a thickness of several tens of micrometers to several hundreds of micrometers in order to secure the optical path length and read resolution characteristics, and the photoelectric conversion element surface 12 side thereof is processed by Santomatting or chemical matting as shown in FIG. It is processed into a satin surface 14 according to the law. This pear surface 14 is
Since the surface roughness affects the light transmittance of the polyester film 7, the surface roughness is finished to about 2 to 8 μm, and the transmittance of the light 11 from the light source 3 is about 90%.

Next, its operation will be explained.

When light 11 from the light source 3 is irradiated from the back side of the sensor substrate 1, the light 11 passes through the sensor substrate 1 and the polyester film 7 and reaches the original 6. When the original 6 is white, the light j1 is reflected and passes through the polyester film 7 again to reach the photoelectric conversion element 12 formed on the sensor substrate 1.
incident on . At this time, the charge accumulated in the photoelectric conversion element 12 in advance is output as a photocurrent proportional to the amount of light.

In this case, the polyester film 7 is
2 is processed into a satin surface 14, thereby preventing the reflection of light 11 from the photoelectric conversion element surface 12 of the polyester film 7, thereby stabilizing the sensor output. On the other hand, when the satin surface 14 is not processed on the photoelectric conversion element surface 12 side of the polyester film 7, when the light 11 is irradiated,
The light 11 that passes through the sensor substrate 1 is transmitted through the light-transmitting upper electrode 1.
Reflection occurs at the contact interface between the polyester film 7 and the photoelectric conversion element 12, resulting in unnecessary and irregular incident light on the photoelectric conversion element 12, making the sensor output unstable.

In addition, although the said Example demonstrated the case where a polyester film was used, it is clear that it is not limited to this.

〔Effect of the invention〕

Since the present invention is configured as described above, it is easy to assemble and can easily secure the optical path length at low cost.

Furthermore, since the reading pixel side of the film is matted in a satin-like manner, reflection of light on the film surface can be reduced, thereby stabilizing the reading output.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a case where a complete contact sensor according to an embodiment of the present invention is mounted on a device, and FIG. 2 is an enlarged view of essential parts of the complete contact sensor shown in FIG. 1. 1...Sensor board, 2...Mounting base, 3...Light source, 4...IC cover, 5...Sensor drive IC1
6... Manuscript, 7... Polyester film, 11.
... light, 12 ... photoelectric conversion element, 13 ... upper electrode, 14 ... pear surface. Agent Patent Attorney Masami Akimoto

Claims (1)

[Scope of Claims] 1. A fully contact type sensor in which a plastic film formed to a thickness sufficient to ensure the length of the optical path reflected from the original is mounted on the sensor substrate. 2. The complete contact type sensor according to claim 1, wherein the plastic film has a matte finish on the reading pixel surface side.