JPS63149775A - Laser light scanning device - Google Patents

Abstract

PURPOSE:To make a device thin in shape by narrowing the path of a signal light through the use of a concaved mirror with a curved surface inside. CONSTITUTION:A scanning light generating part 1 constituted of a revolving mirror, etc., a deflecting system 2 constituted of, at least, one piece of the concaved mirror 22 with the curved surface inside, and a signal detecting system 3 constituted of a converging concave mirror 31 and with an optical detector 32 are provided, and a laser light A is converted into a scanning light B by a scanning light generating part 1. The scanning light B is deflected by the deflecting system 2, and is projected to the outside of the device through a reading window 4 and irradiates a medium 5 to be read such as a bar code etc. A signal scattered light C from the medium 5 is led by the signal detecting system 3 through the deflecting system 2 and the scanning light generating part 1, and is converged at the optical detector 32. It comes possible to make the signal scattered light C, after the deflection of the signal scattered light C by the concaved mirror 22, be parallel, and dimensions in the height direction of the scanning light generating part 1 and the signal detecting system 3 can be reduced, and the device can be made into the thin shape.

Description

[Detailed Description of the Invention] [M Required] Since the signal scattered light C propagates while spreading between the optical systems, a wide area must be secured as a signal optical path for passing it. Therefore, a concave mirror having a curved surface on the inside is used to narrow the signal optical path and make the device thinner.

[Industrial application field]

The present invention relates to a barcode league for reading barcodes on products, and more particularly to a laser beam scanning device that scans a laser beam in a desired direction.

Barcode League, which allows data to be input directly from the checkout counter to the computer, is a point of five (POS) system that can collect sales data in real time.
It is widely used as a terminal in supermarkets and other fields.

However, in supermarkets and the like, multiple barcode leagues are often installed side by side on the same cash register counter, and the devices are required to be miniaturized from the standpoint of freedom of layout and space saving.

There is a strong demand for thinner devices, especially in supermarkets in Europe where operators operate barcode leagues while seated.

As a means for realizing such a barcode league, the laser beam scanning device used therein is required to occupy a small space and be thin.

[Conventional technology]

FIG. 2 is a schematic diagram showing a conventional laser beam scanning device.

In FIG. 2 Tal, the conventional laser beam scanning device includes a scanning light generating section l made up of a rotating mirror or a hologram disk, a deflection system 2 made up of at least one plane mirror 21, a concave mirror 31 for focusing, and A signal detection system 3 comprising a photodetector 32 is provided, and laser light A is converted into scanning light B in a scanning light generating section 1.

The scanning light B generated in the scanning light generating section l is deflected by the deflection system 2.
The beam is deflected by the beam, and is emitted from the reading window 4 to the outside of the apparatus to illuminate the medium 5 to be read, such as a bar code. Signal scattered light C from the medium to be read 5 generated by the irradiation of the scanning light B is guided to the signal detection system 3 via the deflection system 2 and the scanning light generating section 1, and is focused on the photodetector 32.

As shown in FIG. 2 (bl), the signal detection system 3 is composed of a condenser lens 33 and a photodetector 32, and the signal scattered light C from the scanning light generator 1 is condensed onto the photodetector 32 by the condenser lens 33. It's okay to shine.

[Problem that the invention seeks to solve]

However, the signal scattered light C has a property of propagating while spreading inside the optical system, and if this is deflected by the plane mirror 21 and propagated, a wide area must be secured as a signal optical path. As a result, the height hl of the laser beam scanning device becomes large, and there is a problem in that the barcode league cannot be made thinner.

[Means for solving problems]

FIG. 1 is a schematic diagram showing a laser beam scanning device according to the present invention. The same objects are represented by the same symbols throughout the plan.

The above problems are the scanning light generation section 1, deflection system 2, and signal detection system 3.
The scanning light B generated in the scanning light generating section 1 is deflected by the deflection system 2 and emitted from the reading window 4 to the outside of the apparatus to irradiate the medium 5 to be read. The signal scattered light C from the medium 5 to be read is guided to the signal detection system 3 via the deflection system 2 and the scanning light generator 1, and the laser light is focused on the photodetector 32 constituting the signal detection system 3. This problem is solved by the laser beam scanning device of the present invention, which is a scanning device in which the deflection system 2 is configured using at least one concave mirror 22 having a curved surface on the inside.

[Effect]

In FIG. 1, by configuring the deflection system 2 that deflects the scanning light B with at least one concave mirror 22 having a curved surface on the inside, the width in the height direction of the signal optical path through which the signal scattered light C passes is narrowed. , the height of the laser beam scanning device is reduced, and the barcode league can be made thinner.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to FIG.

The laser beam scanning device according to the present invention shown in FIG. Thread 2 and concave mirror 3 for condensing light
1 and a signal detection system 3 constituted by a photodetector 32, and the laser beam A is converted into the scanning beam B in the scanning beam generating section 1.

The scanning light B generated in the scanning light generating section l is deflected by the deflection system 2.
The beam is deflected by the beam, and is emitted from the reading window 4 to the outside of the apparatus to illuminate the medium 5 to be read, such as a bar code. Signal scattered light C from the medium to be read 5 generated by the irradiation of the scanning light B is guided to the signal detection system 3 via the deflection system 2 and the scanning light generating section 1 and is focused on the photodetector 32 .

The signal scattered light C has the property of propagating while spreading, and if it is deflected by a plane mirror, it will continue to spread even after being deflected. However, by deflecting it by a concave mirror 22 having a curved surface on the inside, the signal after being deflected can be For example, the signal scattered light C can be made parallel.

As a result, the optical system that receives the signal scattered light C after being deflected by the deflection system 2, that is, the scanning destination generation section 1 and the signal detection system 3, can be shortened and thinned, and at the same time, the laser beam scanning device The distance in the height direction of the optical system constituting the optical system can be shortened.

In this way, the deflection system 2 is constructed using a concave mirror 22 having a curved surface on the inside.
By configuring this, the width in the height direction of the signal optical path through which the signal scattered light C passes is narrowed, and the height of the laser beam scanning device is reduced to h2, which is smaller than the conventional hc, making it possible to make the barcode league thinner. It can be realized.

Furthermore, it is more desirable to use, for example, a cylindrical concave mirror as the concave mirror 22 having a curved surface on the inside, since the width of the scanning light B in the scanning direction is not reduced. Also the first
As shown in Figure ('b), the reduction ratio of the beam diameter of the scanning light B is different in the vertical and horizontal directions, but the beam diameter is set to be the optimum beam diameter at the position where the medium to be read is irradiated. There is no problem if the laser beam A is corrected.

Furthermore, as shown in FIG. 1(C), the signal detection system 3 can be made thinner by using concave mirrors with different radii of curvature in the vertical direction and the radius of curvature in the horizontal direction as the condensing concave mirror 31 constituting the signal detection system 3. signal scattered light from the medium to be read C
can be focused on the photodetector 32 with high efficiency.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a laser beam scanning device that realizes a thinner barcode league.

[Brief explanation of the drawing]

! Fig. fS1 is a schematic diagram showing a laser beam scanning device according to the present invention, and Fig. 2 is a schematic diagram showing a conventional laser beam scanning device. In the figure, 1 is a scanning light generator, 2 is a deflection system, 3 is a signal detection system, 4 is a reading window, 5 is a medium to be read, 22 is a concave mirror, 31 is a concave mirror for condensing, 32
represent a photodetector, respectively. (-b) Moto Riro += t)'3 L-Sayamu ■1 Fighting Kibe Garden Rod 1
times

Claims (1)

[Claims] 1) A scanning light generator (1), a deflection system (2), and a signal detection system (
3), the scanning light B generated in the scanning light generating section (1) is deflected by the deflection system (2), and is emitted from the reading window (4) to the outside of the apparatus to read the medium (5). At the same time, the signal scattered light c from the medium to be read (5) generated by the irradiation of the scanning light B is detected via the deflection system (2) and the scanning light generating section (1). A laser beam scanning device that guides the laser beam to a system (3) and focuses it on a photodetector (32) constituting the signal detection system (3), the device comprising at least one concave mirror (22) having a curved surface on the inside.
A laser beam scanning device characterized in that the deflection system (2) is constructed using the following. 2) The laser beam scanning device according to claim 1, wherein the concave mirror (22) having a curved surface on the inside is a cylindrical concave mirror.