JP2624688B2 - Optical data recording medium reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention irradiates an optical data recording medium with light, and forms an image on a light receiving element of a sensor by reflecting light from a data recording surface on the medium. The present invention relates to an optical data recording medium reading device that reads recorded information through an optical data recording medium.

[Conventional technology]

Generally, bank cards, credit cards, and other optical data recording media (optical data cards) on which information is optically recorded are known as data recording media. Among them, the reading device of the optical data card is generally the second device.
It has a configuration as shown in the figure. The outline will be described below. In FIG. 2, the card 15 is a data recording medium for optically recording information. And this card 15
The light source 14 irradiates the light upward, and the line sensor 11 reads the recorded information. In this optical data card reader, the light from the light source 14
And is irradiated onto the card 15. The light reflected on the card 15 is received by the line sensor 11 through the imaging lens 12. Therefore, information can be read by performing electrical scanning with the line sensor 11.

[Problems to be solved by the invention]

By the way, in the conventional reading apparatus shown in FIG. 2, the imaging lens 12 used for data reading has a wider field of view which is advantageous for high-speed reading, and has the same level of brightness over the entire field of view. Obtaining an image makes it possible to simplify data processing after signal reading. However, the spherical lens for imaging used in the conventional reader is
In order to widen the field of view, it is necessary to shorten the focal length or enlarge the aperture, that is, to reduce the numerical aperture. On the other hand, to obtain uniform brightness over the entire field of view,
It is necessary to increase the focal length, that is, to increase the numerical aperture, and it is difficult to achieve both.

In addition, the enlargement of the lens diameter for the purpose of enlarging the field of view restricts the installation position of each optical component, is disadvantageous in the design of the optical system, and has a problem that the apparatus becomes large.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an optical data recording medium reading device capable of simplifying data processing while increasing the field of view and reducing the size of the device. It is the purpose.

[Means for solving the problem]

Therefore, the optical data recording medium reader of the present invention irradiates light from a light source at an incident angle θ to a relatively moving optical data recording medium that records information two-dimensionally,
An optical data recording medium reading device for reading recorded information by forming reflected light reflected at a reflection angle θ from a data recording surface on the medium by an imaging lens on a light receiving element of a line sensor, The optical data recording medium is disposed in a direction orthogonal to the moving direction of the optical data recording medium, and has the same length as the recording width of the optical data recording medium in a direction parallel to the orthogonal direction. The range equivalent to the light receiving element array length of the line sensor of the data recording medium,
Or, using a linear light source that evenly illuminates a greater range, using a cylindrical lens as an imaging lens,
This cylindrical lens is disposed in a direction orthogonal to the moving direction of the optical data recording medium, and the length in the direction parallel to the orthogonal direction is equal to or longer than the array length of the light receiving elements of the line sensor. In addition, the magnification of the line sensor in the light receiving element array direction is the same, and the magnification in the direction perpendicular to the array of the light receiving elements is enlarged or reduced, and is arranged on the front surface of the line sensor so as to be able to be reduced. Thereby, the linear light of the light source is incident on the data recording surface of the optical data recording medium, and the data recording surface is uniformly irradiated with a range equal to or longer than the length of the light receiving element array length of the line sensor, The reflected light reflected from the data recording surface is formed into a linear image in the direction of arrangement of the light receiving elements of the line sensor by a cylindrical lens to form an image, and the information recorded on the optical data recording medium is scanned. Wherein the read by.

[Action]

In the optical data recording medium reading device of the present invention, a cylindrical lens is used as the imaging lens, a linear light source is used as the light source, and a linear image is formed in the same direction as the line sensor light receiving cell array direction. At the same time, the field of view in the light receiving cell array direction was expanded and the light receiving intensity level was made uniform, and at the same time, the size of the device could be reduced.

〔Example〕

 Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 is a schematic perspective view of an optical data recording medium reader for explaining one embodiment of the present invention. In FIG.
An optical data recording medium 5 is provided on a card base material 6. In order to reproduce information recorded on the optical data recording medium 5, a light source 4, an imaging lens 3 for imaging reflected light from the medium, and a light receiving line sensor 1 are provided. . The light source 4 has a linear illumination range by an LED array or the like, and is converged on a medium in parallel with the X direction. Illumination range is X
The light is irradiated at an angle equal to or greater than the length of the light receiving portion in the direction and at an angle of θ with the optical data recording medium 5. A cylindrical lens is used as the imaging lens 3 and is installed so that the magnification in the vertical direction with respect to the light receiving cell 2 is variable. Light reflected from the optical data recording medium 5 at an angle of θ is reflected by the line sensor 1. An image is formed on the light receiving cell 2. X of imaging lens 3
The length in the direction is equal to or longer than the length of the light receiving cell 2 of the line sensor 1.

By using the above-described optical system, the unevenness of the light intensity distribution of the image in the X direction by the imaging lens 3 is eliminated, and the unevenness of the read signal is only the unevenness of the light source. In the experiment of the present invention, by using the LED array as the uniform light source, a uniform line sensor read signal was obtained, and the subsequent data processing became easy. The reading field has the same range as the length of the line sensor light receiving section, and a wide range of information can be read on the advanced data recording medium, and the information reading speed has been improved. In addition, by using a cylindrical lens as the imaging lens, the selection range of the incident angle and the reflection angle θ is widened, and the apparatus can be downsized.

〔The invention's effect〕

As is clear from the above description, according to the present invention, a cylindrical lens is used as an imaging lens, and this cylindrical lens has a length equal to or longer than the light receiving element array length of the line sensor, The magnification in the line sensor light receiving unit array direction is the same, and the magnification in the direction perpendicular to the array of light receiving elements is arranged on the front of the line sensor so that it can be enlarged or reduced. Of the data recording surface of the dynamic data recording medium, a range equivalent to the length of the light receiving element array of the line sensor, or a configuration using a linear light source that uniformly illuminates a range longer than that, The reading field of view is wide and uniform brightness can be obtained over the entire field of view. Size of the device due to expansion of's diameter is eliminated, and therefore, the angle of incidence, and spreading the selection range of the reflection angle, it is possible to reduce the size of the apparatus. Further, scanning and reading of an optical data recording medium such as a bank card or a credit card can be performed while expanding the reading field of view while equalizing the light intensity level on the line sensor light receiving section. And the reading speed can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of an optical data recording medium reader for explaining one embodiment of the present invention, and FIG. 2 is a diagram showing a conventional example of an optical data recording medium reader. DESCRIPTION OF SYMBOLS 1 ... Line sensor, 2 ... Light receiving cell, 3 ... Cylindrical lens, 4 ... Light source, 5 ... Optical data recording medium, 6 ... Card base material.

Claims (1)

(57) [Claims] 1. A light source irradiates light at an incident angle θ to a relatively moving optical data recording medium on which information is recorded two-dimensionally, and is reflected at a reflection angle θ from a data recording surface on the medium. In an optical data recording medium reading device for reading recorded information by forming reflected light into an image on a light receiving element of a line sensor by an imaging lens, a direction orthogonal to a moving direction of the optical data recording medium is used as the light source. And has the same length as the recording width of the optical data recording medium in a direction parallel to the orthogonal direction, and the length of the light receiving element array of the line sensor of the optical data recording medium. A linear light source that uniformly illuminates a range equivalent to or greater than the above range, a cylindrical lens is used as an imaging lens, and the cylindrical lens is used as the optical data recording medium. Arranged in the direction orthogonal to the moving direction, and the length in the direction parallel to the orthogonal direction is equal to or longer than the array length of the light receiving elements of the line sensor, and the light receiving element of the line sensor The magnification in the array direction is unity,
By enlarging or reducing the magnification in the direction perpendicular to the arrangement of the light receiving elements, the linear light of the light source is arranged on the front surface of the line sensor so as to be able to reduce the data of the optical data recording medium. Incident on the recording surface, of the data recording surface, a range equivalent to the array length of the light receiving elements of the line sensor, or uniformly illuminate the range more, reflected light reflected from the data recording surface, An optical data recording medium reading apparatus, wherein the cylindrical lens forms a linear image in a light receiving element arrangement direction of a line sensor to form an image, and scans and reads information recorded on the optical data recording medium.