JPS6320954A - Reading sensor - Google Patents

Abstract

PURPOSE:To improve the performance of the titled sensor by constituting an illumination system, a rod lens array, and a photodetecting part inside a cylindrical transparent glass which rotates at the same speed with the transferring speed of an original to prevent dusts from sticking to the rod lens array and others and to maintain a constant quantity of receiving light. CONSTITUTION:The cylindrical transparent glass 12 sandwiches the original 1 jointly with a roller 7 being drive by a motor through gears 13 and 14. The circumferential speed of the roller 7 and that of the glass 12 are made equal. A base 15 fixed at the side wall of the device is inserted in a cylindrical transparent glass 12, and the illumination system 4, the rod lens array 3, and the photodetecting part 5 equipped with a photodetecting element array 6, are fixed on the base 15. The light beams emitted from the illumination system 4 transmit through the cylindrical transparent glass 12, and illuminate the original 1. The reflecting light beams are made form an image on the photodetecting element array 6 on the photodetecting part 5 by the rod lens array 3. A lead wire to the reading sensor is drawn out of the cylindrical transparent glass 12 running along the base 15.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a reading sensor.

(Prior art) Figure 3 shows an example of the configuration of a conventional well-known reading sensor (6
Collection of papers from the 1st Annual National Conference of the Institute of Electronics and Communication Engineers.

Paper number 1254a-8 Top contact type image sensor, No. 5
99), 1 is a document, 2 is a transparent flat glass, 3 is a rod lens array, 4 is an illumination system, 5 is a diagram showing
1 is a light receiving section, 6 is a light receiving element array provided on the light receiving section 5, and 7 is a roller for feeding the document.

The light emitted by the illumination system 4 passes through the transparent flat glass 2 and illuminates the original 1.
to illuminate. The reflected light from the original 1 is imaged by the rod lens array 3 on the light receiving element array 6 on the light receiving section 5, and the magnitude of the reflected light is detected. The document 1 is made to be moved by rollers 7 on the surface of the transparent flat glass 2 in the direction indicated by the arrow, and the characters and figures written on the document 1 are read.

FIG. 4 is a diagram showing another example of the configuration of a conventional reading sensor.

8 is a -14- guide on the movement start side of document 1;
is the other -/4-guide corresponding to the to-be-performed guide 8. Reference numeral 10 indicates the tip of the second perpendicular guide 9, which is bent toward the rod lens 3 side. 11 is an opening provided in the center of the id 8, 9.

The light emitted by the illumination system 4 passes through the opening 11 and illuminates the original 1. The reflected light from the original 1 passes through the rod lens array 3 and enters the light receiving element array 6. The document 1 is configured to be moved in the direction of arrow A by each roller 7,
Read the characters, figures, etc. written on manuscript 1.

(Problems to be Solved by the Invention) However, in the configuration shown in FIG. 3 above, the document 1 moves while rubbing the two sides of the transparent flat glass, so there is a drawback that the two sides of the transparent flat glass get scratches and dirt. Also, when the original 1 moves at a high speed, for example, around 2 meters/second, the original 1 vibrates slightly on the transparent glass 2 surface, deviating from the focal position of the rod lens array 3, and causing the rod lens array 3 to move slightly. Since the angle between the optical axis and the document 1 constantly changes, there is a drawback that the amount of light received by the light receiving element array 6 changes greatly. Furthermore, in addition to the above-mentioned drawbacks, the configuration shown in FIG. 4 also has the drawback that dust, paper powder, etc. adhere to the rod lens array 3 and the like, reducing the amount of light received by the light receiving cable 6.

The present invention eliminates the above-mentioned drawbacks such as large changes in the amount of light received due to scratches and dirt on the glass surface, microvibrations of the document, and furthermore, a decrease in the amount of light received due to dust and paper dust, and a reading sensor that always maintains a stable amount of light received. It provides:

(Means for Solving the Problem) The present invention provides a sensor for reading characters, figures, etc. written on a document, which includes a rotatable cylindrical transparent glass, an illumination system inside the cylindrical transparent glass, and a rod lens array for receiving light. A department was established.

(Function) The rod lens array and sensor, which are sensitive to dirt, are protected by a cylindrical transparent glass, and the cylindrical transparent glass is rotated as the document moves to reduce the occurrence of scratches on the glass surface.

(Embodiment) FIG. 1 is a cross-sectional configuration diagram showing an embodiment of the present invention, and FIG. 2 is a perspective view of FIG. 1.

The cylindrical transparent glass 12 is configured to rotate with the original 1 sandwiched between the roller 7 and gears 13 and 14 by rotation of a motor (not shown). It goes without saying that the peripheral speed of the lath 12 of the roller 7 and the cylindrical transparent roller is the same, but the rotation directions are different. Cylindrical transparent glass 1
2 includes a base 15 fixed to the side wall of the device (not shown).
is inserted and the lighting system 4. Rod lens array 3. A light receiving section 5 on which a light receiving element array 6 is mounted is fixed to a base 15.

The light emitted by the illumination system 4 passes through the cylindrical transparent lath 12,
Irradiate original 1. The reflected light is reflected by the rod lens array 3.
As a result, an image is formed on the light receiving element array 6 on the light receiving section 5. A lead wire to the reading sensor is taken out along the base 15 to the outside of the cylindrical transparent glass 12.

(Effects of the Invention) As described above in detail, according to the present invention, since the illumination system, rod lens array, and light receiving section are configured inside the cylindrical transparent glass that rotates at the same circumferential speed as the moving speed of the original, As the document moves, the surface of the cylindrical transparent glass will not be scratched, and even if the document is moving at high speed, the document will not cause slight vibrations between the cylindrical transparent glass and the roller. It is clear that there is no possibility that paper dust or the like will adhere to the rod lens array or the like. In other words, it is necessary to always maintain a stable amount of received light, resulting in a reading sensor with extremely high performance.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
The perspective view and FIGS. 3 and 4 are explanatory diagrams of the prior art. 1... Original, 3... Rod lens array, 4...
Illumination system, 6... Light-receiving element array, 12... Cylindrical transparent glass O 2 Feet Feet I Party I Party Iku 9 Sea Giga

Claims (1)

[Claims] A sensor for optically reading characters, figures, etc. written on a document, comprising: a document illumination unit lens system fixed to a non-rotatable holder;
The optical part consisting of the light receiving part is inside a completely transparent cylinder.
The rotatable cylinder is arranged and fixed so that the focal point of the lens system coincides with the outer surface of the cylinder, and the rotatable cylinder contacts the roller for feeding the document at the focal position of the lens system, and the circumferential speed of the cylinder and the roller A reading sensor characterized in that a circumferential speed matches a document moving speed, and the document is moved while being sandwiched between the roller and the cylinder.