JPS6068477A - Optical reader - Google Patents

Abstract

PURPOSE:To eliminate an adjustment job despite the exchange of an optical system or a laser tube and to obtain a constant quantity of outgoing light, by dividing an optical reader into an optical system unit and a laser unit part and setting both the incident and outgoing light quantities at a fixed level. CONSTITUTION:An optical reader 4 is divided into an optical system unit 11 and a laser unit 12. A filter assembly 13 containing a light quantity control means is set at an incident part of the laser light r of the unit 11. While another filter assembly 13 having a control means for outgoing light quantity of the light R is set opposite to the light emitting surface of a laser tube 6. The area between both assemblies 13 is covered with a cylindrical packing 16 made of sponge rubber, etc. Then a cylindrical packing 17 is set between the tube 6 and a flange 14. Both the incident and outgoing light quantities of units 11 and 12 are set at a fixed level respectively. Then eliminates an adjustment job despite the exchange of the tube 6 or the unit 11.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to an optical reading device for reading barcodes etc. printed on media used in PO3 (Point Of 5ales) systems.

(bl) Background of the Technology Recently, with the spread of computer network systems, electronic cash registers and stationary reading devices have been used as OS terminals in department stores, supermarkets, etc. These terminals are installed at payment counters, are operated by operators such as store clerks, and are used to read barcodes printed on product labels and the like using reading devices. The barcode displays the product number, product name, and product price. When the barcode is read, the prices are sequentially displayed on the display of the electronic register, and finally the total price is displayed according to the push button instruction. In addition to register functions, this terminal also functions as a data machine for an information management system that sends sales information for each product online to a computer center for sales aggregation, and performs comprehensive product management such as inventory management and purchase management. It's one wing.

(C1 Prior Art and Problems) A stationary reader used in a POS system will be explained below with reference to FIGS. 1 and 2. FIG. 1 shows a barcode reader to which the present invention is applied. FIG. 2 is a perspective view illustrating the state of use, and FIG. 2 is a side sectional view illustrating the outline of the structure of the device.

As shown in FIG. 1, a checkout operator at a supermarket moves the products 2 with barcodes 3 one by one from one basket to another at the counter in the direction of the arrow (■) without stopping. In this case, the product needs to pass over the transparent window 5 of the reading device 4 within a predetermined dimension. Then, the light (arrow R) emitted from the reading device 4 through the transparent window 5 scans the barcode 3 attached to the product 2, and the reading device 4 reads the reflected light.

Although the structural outline of the reading device is not shown in FIG. 2, the laser beam emitted from the laser tube 6 is reflected by the mirror 7 as shown by the dashed line and enters the hologram disk 9 rotating at high speed in the morph 8. Then, the diffracted light from the hologram disk is polarized, enters the mirror 10, and is emitted from the reading device 4 through the transparent window 5 by reflection. At this time, the emitted beam is swung in a plurality of predetermined directions by the rotation of the hologram disk 9.

With the above configuration, laser light is emitted to the outside of the apparatus, but in the past, the amount of light emitted to the outside of the apparatus varied depending on the diffraction efficiency of the hologram disk and the difference in the output of the laser tube. However, in order to provide a barcode reader with higher safety, it is necessary to set an upper limit on the amount of emitted light, and if the amount of emitted light is small, the reading performance will deteriorate. Therefore, it became necessary to set the output to the upper limit of the allowable amount of output light.

(di Purpose of the Invention The purpose of the present invention is to solve the above-mentioned problems, and to provide a system in which the amount of light emitted from the device is within the specified value, and even if the laser tube or optical system is replaced, the amount of light emitted from the device can be adjusted without any particular adjustment work. We will introduce an optical reading device that does not change.

(el) Structure of the Invention In order to achieve the above object, the present invention uses a laser beam emitted from a laser tube inside the device to scan a code or image outside the device using an optical scanning device. An optical reading device for reading reflected light, comprising: a first optical filter disposed at a position facing the light emitting surface of the laser tube to adjust the amount of emitted light; 1st
A filter is provided to face the optical filter and adjust the amount of incident light.

(fl Embodiment of the Invention An embodiment of the invention will be described below with reference to FIGS. 3 to 6.

FIG. 3 is a side sectional view illustrating the outline of the structure of the optical reading device according to the present invention, FIG. 4 is an enlarged view of section A in FIG. 3, FIG. 5 is a side sectional view of the filter assembly 13, and FIG. FIG. 5 is a view taken along arrow B in FIG. 5;

In the figure, 11 is an optical system unit section, 12 is a laser unit section, 13 is a filter assembly, I6.17.18
is the packing, 19 is the mounting bracket, 20 is the filter, 21'
is a ring, 22 is a set screw, 23 is a small hole, and 24 is a mounting screw.

Items with the same reference numerals throughout the plan are the same.

As shown in FIG. 3, the reading device 4 according to the present invention is constructed by separating the layers into an optical system unit section 11 and a laser unit section 12, and connecting the layers to each other.

That is, the internal structure of the optical system unit section] 1 is the same as that of the prior art example, but a filter assembly 13 having a light amount adjusting means whose detailed structure is shown in FIG. be.

On the other hand, in addition to the laser tube 6, the laser unit section 12 is provided with a filter 13 facing the light emitting surface of the laser tube 6 and having means for adjusting the amount of emitted laser light (arrow R) as described above. It is being

The filter assembly 13 is the optical system course throat part 11
In the laser 1 unit 12, the flange 15 attached with the mounting screw 24 is loosely fitted through the packing (= the flange 14 attached with the J metal fitting 19). It is loosely fitted.

A cylindrical gasket 16 made of sponge rubber or the like is formed between the opposing filter and nozzle 13 phases L18.
Similarly, a cylindrical packing 17 is interposed between the laser tube 6 and 797214 in the optical system, part 1, j1.

Filter assembly l 3 L; l: Figures 5 and 0
It has a configuration as shown in Figure 1. Figure ff55 shows the state of the laser unit section 12, and the ring 13 loosely fitted into the flange 14 (or 15 in the optical system unit section 11) is rotatable within the flanges 14 and 15. It is fixed by set screws 22 provided on the flanges 14 and 15. ring 2
A filter 20 is fixed to the flange 14.
It functions to transmit the laser light (arrow R) emitted through the small hole 23 and adjust the amount of light. filter 20
The transmittance of is changed analogously, and the right end part 2
4 has a low transmittance, and a region is defined in which the transmittance gradually increases from the center portion 25 to the left end portion 26. Therefore ring 2
1, the transmittance changes and the laser unit part 1 changes.
The output light amount of 2 can be divided into four sections. The purpose of providing the adjustment means for the amount of emitted light from the laser unit section 12 is to correct variations in the amount of emitted light from the laser tube 6 and to keep the amount of emitted light from the laser unit section 12 constant at a specified value.

Further, the purpose of providing a means for adjusting the amount of incident light in the optical system unit section 11 is because the hologram disk 9 has a difference in Borodalum efficiency, and even if the amount of laser light incident on the optical system unit section 11 is constant, the amount of output light will vary. This is to correct this constant.

By configuring the optical system unit section 11 and the laser unit section 12 in this manner, they are compatible with each other, and if it becomes necessary to replace the laser tube 6 or the optical system, for example, the same adjustment work can be performed. Now it can be easily replaced without having to do anything.

(gl As described in detail, the present invention is capable of interoperating with each other by separating the reading device into an optical system unit section and a laser unit section and setting the amount of incident light and the amount of output light of each at a constant value. The new compatibility has made it possible to easily assemble the reading device and replace the laser tube and optical system without having to perform difficult four-section work.

[Brief explanation of drawings]

FIG. 1 is a perspective view illustrating the usage state of an optical reading device to which the present invention is applied, FIG. 2 is a side sectional view illustrating the outline of the structure of the device, and FIG. 3 is a structure of the optical reading device according to the present invention. 4 is an enlarged view of part A in FIG. 3, FIG. 5 is a side sectional view of the filter assembly 13, and FIG.
The figure is a view taken in the direction of arrow B in FIG. In the figure, 2 is the product, 3 is the barcode, 4 is the reader, °
5 is a transparent window, 6 is a laser tube, 7.10 is a mirror, 8 is a motor, 9 is a hologram disk, 11 is an optical system unit part, 12 is a laser unit part, 13 is a filter assembly, 16.17.18 is a packing , 19 is a bracket (-1 metal fitting, 20 is a filter, 21 is a ring, 22 is a set screw, 2
3 is a small hole, and 24 is a mounting screw. Rod 1 Dango 2 Zucha 4 Mouths

Claims (1)

[Claims] An optical reading device that scans a code or image outside the device with a laser beam emitted from a laser tube inside the device using an optical scanning device and reads the reflected light, and is located at a position opposite to the light emitting surface of the laser tube. is installed to increase the amount of emitted light to l! An optical reading device comprising: a first optical filter that receives the emitted light; and a filter that is provided at an entrance of an optical system that receives the emitted light, facing the first optical filter, and that adjusts the amount of incident light.