JPH02163722A - Scanner device - Google Patents

Abstract

PURPOSE:To easily vary the depth of a read by converging the scattered signal light of laser light from a sample, switching beam expanders different in characteristics in the scanner device which sends the converged beam to a photodetector. CONSTITUTION:The scattered signal light L1 from a bar code 3a travels along almost the same optical path with the incident light L'' to strike on a concave mirror 13, and is further converged on the photodetector 23 through a mirror 22. At this time, the depth of a read of the laser light L in the read window 21 by, for example, a beam expander 41a is 0 - 10cm. When an article 3 is at a distance of >=10cm from the window 21, the bar code can not be recognized with the laser light L. At this time, a disk 40b for operation is rotated in a direction R and the beam expander is switched to an expander 41b which has long focal length. Thus, the expanders 41a, 41b... which differ in focal length are switched to easily select the depth of the read.

Description

[Detailed Description of the Invention] [1 Already Required] Regarding a laser beam scanner device in a barcode reader, etc., the reading depth of code information, etc. is variable to expand the usable range of one scanner device, thereby increasing productivity. In a scanner device that scans and emits a laser beam with a predetermined beam diameter from a reading window, and converges the scattered signal light from a sample located near the reading window and sends it to a photodetector,
The beam expander is configured to include beam expanders each having different characteristics and a switching means for switching the beam expander.

[Industrial application field]

The present invention relates to a code information reading device such as a barcode reader, and more particularly to a scanner device which aims to expand the range of use by making the reading depth of code information etc. variable.

First of all, code information reading devices such as barcode leagues are widely used as terminals that connect to computers and collect various information in real time. A plurality of reading devices, either of a flat type with a horizontal reading surface or a vertical type of reading device with a vertical reading surface, are often installed on various tables.

In particular, with conventional scanner devices, for example, there are restrictions on the distance range from the reading window surface to the code information position (hereinafter referred to as the reading depth of code information, etc.) in order to reliably recognize code information. At present, multiple types of scanner devices are prepared for different depths, and each type is used depending on the need.

[Conventional technology]

FIG. 2 is a diagram showing an example of the configuration of a scanner device, (8)
(B) represents a perspective view, and (B) represents a side view.

In Figures 2 (A) and 2 (B), which take as an example a flat-mounted barcode reader with a reading window installed in the horizontal direction, the scanner device is roughly divided into a scan pattern forming section 1 and a reading section 2. has been done.

The scan pattern forming section 1 includes a laser light source 10. Beam expander 11. Mirror 12. Micromirror 13 in the center
Concave mirror equipped with a 13. It is composed of a polygon mirror 14 that rotates at high speed, for example, in the direction of the arrow shown in the figure, and a pattern forming mirror 15 consisting of three mirrors 15a, 15b, and 15c arranged in a ladder shape that widens toward the end so as to surround the polygon mirror 14, and A reading section 2 that shares a part of the scan pattern forming section 1 is a reading window 2 made of a hologram that diffracts pattern scanning lines in three equiangular directions shifted by 120 degrees on a plane in a predetermined direction.
1, a mirror 22, and a photodetector 23.

Note that 3 located above the reading window 21 in the figure represents a product, and a barcode 3a, for example, is displayed on the side of the product 3 facing the reading window 21.

Further, numeral 30 in the figure represents a part of the casing that houses the above-mentioned scan pattern forming section 1 and reading section 2.

The case of reading a barcode will be explained below.

The laser light shown by the dotted line emitted from the laser light source 10 is made into a laser light with a predetermined diameter by the beam expander 11, and after being reflected by the mirror 12, it is further reflected by a micromirror 13a mounted approximately at the center of the concave mirror 13. The light is incident on the mirror surface formed around the polygon mirror 14.

As described above, this polygon mirror 14 is rotating at high speed, for example in the direction of the arrow in the figure, so the micromirror 13a
After being reflected by the mirror surface of the polygon mirror 14, the laser beam entering the pattern forming mirror 15 moves from 15a to 15b.
→The laser beam L' scans in the directions of arrows ■, ■, ■ in the order of 15c, is reflected by each mirror surface, and advances toward the reading window 21.

On the other hand, in the reading window 21 made of a three-layer hologram, the laser beam L' reflected from the mirror 15a of the pattern forming mirror 15 is reflected from the area (■1), and the laser beam L'' reflected from the area 5b is reflected from the area (■'). From the area.

Further, the respective regions ■°, ■゛, ■° are the above-mentioned mirrors so that the laser beam L" reflected from L5c is emitted as a diffracted laser beam LIT from the region ■゛, respectively.
, 5a, 15b, and 15c.

This means that the diffracted laser beam LFr emitted from the reading window 21 is sequentially emitted while sequentially scanning the area ``■'', the area ``■'', and the area ``■'' along the longitudinal direction. As a result, the reading window 21
This shows that the diffracted laser beam LIT scans the barcode 3a vertically, no matter what direction the barcode 3a facing the reading window 21 of the product 3 located above is lined up.

On the other hand, the scattered signal light from the barcode 3a follows almost the same optical path as the incident light, enters the concave mirror 13 disposed close to the mirror 1.5b, is further reflected by the concave mirror 13, and is detected as light. It is configured to converge on the vessel 23.

Therefore, the barcode is read by making the optical signal recognized by the photodetector 23 correspond to the striped pattern of light and shade of the barcode 3a.

Note that the mirror 22 is for changing the direction of the scattered signal light.

In a flat-mounted scanner device having such a configuration, the operator usually moves the barcode 3a of the product 3 by rubbing the upper surface of the reading window 21 to cause the scanner device to read it. There is little variation in the distance from the surface of the reading window 21, and therefore, in this case, it is sufficient to have a reading depth of at most about 10 ca+ from the surface of the reading window 21.

On the other hand, in a vertical scanner device in which the reading window 21 is installed in a vertical direction facing the worker, the worker can read the barcode 3a by moving the product 3 at hand without touching the reading window 21. many. This means that the distance of the barcode 3a from the surface of the reading window 21 varies widely, and in order to cope with this, for example, the reading depth of the scanner device is set to 10 cm above the surface of the reading window 2I. The cutting depth is set to be thick (and deep) such as 31f, so that it satisfies the range of about 25 cor.

Conventionally, therefore, measures have been taken, such as, for example, preparing separate scanner devices for a flat surface installation type and a vertical installation type, and using them as needed.

[Problem to be solved by the invention]

A scanner device having a conventional configuration has a problem in that scanner devices having different reading depths must be prepared separately depending on the installation form of the scanner device and the position of code information, etc.

[Means to solve the problem]

The above problem arises in scanner devices that scan and emit laser light with a predetermined beam diameter from a reading window, converge the scattered signal light from a sample located near the reading window, and send it to a photodetector, each of which has different characteristics. The problem is solved by a scanner device including a beam expander and a switching means for switching the beam expander.

[For production]

Generally, the reading depth in a scanner device depends on the beam diameter of the scanning laser beam6, and the beam diameter can be controlled by a beam expander provided in the optical path.

In the present invention, a plurality of beam expanders are provided in the optical path of a conventional scanner device, and the plurality of beam expanders are configured to be easily switched by an operation from outside the device.

Therefore, it is possible to freely change the reading depth of the scanner device, and it is possible to configure a scanner device that can obtain reliable code information with a number of scanner devices, regardless of the installation form of the scanner device or the position of code information, etc. be able to.

〔Example〕

FIG. 1 is a diagram showing an example of the structure of a scanner device according to the present invention, in which (A) is a perspective view and (B) is a sectional view of the main part.

Note that FIG. 1(A) shows a state in which a variable beam expander is installed in place of the beam expander in FIG. 2, and other parts are the same as in FIG. 2.

In Figures (A) and (B), 40 denotes a plurality of (six in the figure) beam expanders 41a, 41b, . . . which have different focal lengths for the laser light emitted from the laser light source 10.
represents variable beam expanders arranged at approximately equal intervals on the circumference so as to be parallel to the optical axis of the cough laser beam, and each of the beam expanders 41 is placed on the central axis of the variable beam expanders.
A rotation axis 40a parallel to a, 41b, 41c,...
Further, an operating dial 40b is provided on the outer end of the rotating shaft 40a passing through the hole 30a of the housing 30.
It can be fixed from the outside of 0.

Furthermore, 42 in the figure is a flange 42 at a predetermined position inside the housing 30.
The beam expander 41.a rotates with the optical axis of the laser beam while the rotating shaft 40a is rotatably inserted into a through hole 42b which is fixed in the bearing along its longitudinal direction. a+ 41b, 41c, . . . are configured so that their respective central axes coincide with each other in sequence.

Therefore, the bearing 420 is fixed at a predetermined position in the housing 30.
The rotation shaft 4 of the variable beam expander 40 is inserted into the through hole 42b.
0a from inside the housing 30, a dial 40b is attached to the end of the rotating shaft 40a that protrudes outside the cough housing 30.
is fixed.

The optical path will be explained below.

Laser light shown by a dotted line emitted from a laser light source 10 placed at a predetermined position in the housing 30 is shaped into a predetermined diameter by a beam expander 41a, reflected by a mirror 12, and then further reflected by a micromirror 13a of a concave mirror 13. The light then enters the mirror surface formed around the polygon mirror 14.

As explained in FIG. 2, this polygon mirror 14 is rotating at a high speed, for example, in the direction of the arrow shown in the drawing, so that the laser beam incident from the micromirror 13a is reflected by the mirror surface of the polygon mirror 14, and then the pattern forming mirror 15a ,
The laser beam L' is reflected while sequentially scanning each surface of 15b and 15c as shown in FIG. 2, and advances toward the reading window 21.
becomes.

After that, the corresponding area ■“, ■, ■“ of the reading window 21
(in the case of the figure, the area of ■°) is emitted as a diffracted laser beam LIT, and the barcode 3 faces the reading window 21 of the product 3 located above the reading window 21.
The scanning of a is as explained in FIG.

On the other hand, the scattered signal light from the barcode 3a follows almost the same optical path as the incident light, enters the concave mirror 13, passes through the mirror 22, and converges on the photodetector 23.

Therefore, as described above, the barcode is read by making the optical signal recognized by the photodetector 23 correspond to the striped pattern of light and shade of the barcode 3a.

At this time, for example, the reading depth of the laser beam Ltt on the reading window 21 by the beam expander 41a is 0 to 1.
0cm, and product 3 is 10cm from the surface of reading window 2.
If the barcode of this product is located at a distance of n+ or more, the barcode of this product cannot be recognized by the laser beam L1'.

In this case, the operating disk 40b may be moved to R as shown in the figure, for example.
The reading depth of the laser beam LH is lengthened and deepened by rotating the beam expander 1 in the direction and passing the laser beam through the beam expander 1, for example 41b, which has a longer focal length than the beam expander 41a, thereby making it possible to recognize the barcode.

In the scanner device having such a configuration, a plurality of beam expanders 41a attached to the variable beam expander 40 are used.
, 41b, 41c, . . . The beam diameter of the laser beam L11 that scans the barcode can be changed by changing the focal length of each of the laser beams L11, 41b, 41c, .
The desired reading depth can be easily selected by rotating 40b from outside the device.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to easily provide a scanner device with a variable reading depth that can be used in either a horizontal installation type or a vertical installation type.

In Figure 0, 3 is the product, 3a is the bar code, 10 is the laser light source, 12. 15a, 15b, 15c, 22 is the mirror 13 is the concave mirror, 13a is the micro mirror 14, the polygon mirror 15 is the pattern forming mirror 2. is a reading window, 23 is a photodetector, 30 is a housing, 30a, 42b are through holes, 40 is a variable beam expander, 40a is a rotation axis, 40b is a dial, 41a,
41b, 41c, 41d, ++ represent a beam expander, 42 a bearing, and 42a a flange, respectively.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the configuration of a scanner device according to the present invention;

Claims (1)

[Scope of Claim] A scanner device that scans and emits a laser beam with a predetermined beam diameter from a reading window, converges a scattered signal light from a sample located near the reading window, and sends it to a photodetector. A scanner device comprising different beam expanders and switching means for switching between the beam expanders.