JPH03230286A - Bar code reader - Google Patents

Abstract

PURPOSE:To obtain a bar code reader having a wide reading area by successively inserting plural lenses held by a frame and having respectively different focal distances into a beam optical path system applied from a light source and periodically irradiating a target with scanning beams having respectively different focal positions. CONSTITUTION:The plural lenses 2A to 2N held by the frame l and having respectively different focal distances are successively inserted into the beam optical path system applied from the light source 3 to periodically irradiate a target with scanning beams having respectively different focal positions. Namely, plural scanning beams to be focused on different positions with the lapse of time are formed by successively inserting the lenses having respectively different focal distances into the optical path system. Plural different reading areas are formed on a device body 5 and a bar code positioned on any one of the areas is read out by the scanning beams constituting the area. Consequent ly, the reading area can be practically expanded.

Description

[Detailed description of the invention] [a required]

Regarding barcode readers, we aim to provide a barcode reader with a wide reading area by sequentially inserting multiple lenses with different focal lengths held in a frame into the beam optical path system from a light source, and periodically adjusting the focal position. It is configured to irradiate different scanning beams.

[Industrial application field]

The present invention relates to a barcode reader. In recent years, POS systems have been introduced in department stores, supermarkets, etc. for the purpose of streamlining product management and checkout operations. This system manages products by reading barcodes attached to products with a barcode reader device, and there is a need for a barcode reader device with high barcode reading efficiency.

[Conventional technology]

FIG. 4 shows the optical system of a conventional barcode reader. 3 is a laser tube as a light source, 4 is a mirror for changing the optical path, and the beam from the light source 3 is focused by a lens 2, and the beam from the main body 5 of the device is A predetermined beam diameter is obtained at a predetermined height.

[Problem to be solved by the invention]

However, in the above conventional example, since the beam is narrowed down using one type of lens 2, the focal length is predetermined at one location, and barcodes can only be read in the vicinity of that location, resulting in a narrow reading area. It had the following drawbacks. The present invention has been made to solve the above-mentioned drawbacks, and an object of the present invention is to provide a barcode league with a wide reading area.

[Means to solve the problem]

According to the present invention, the above object is to sequentially insert a plurality of lenses 2A, 2B, etc. with different focal lengths held in the frame 1 into the beam optical path system from the light source 3, and periodically irradiate scanning beams with different focal positions. This is achieved by providing a barcode league. Further, the plurality of lenses 2 may be held by the frame 1 which rotates intermittently, and furthermore, the plurality of lenses 2 may be held by the frame 1 which moves back and forth intermittently.

[Effect]

Based on the above configuration, in the present invention, by sequentially inserting lenses 2 having different focal lengths into the optical path system, a plurality of scanning beams that are focused at different positions over time are formed. As a result, a plurality of different reading areas are formed on the main body 5 of the apparatus, and a barcode located in any one of the areas is read by the scanning beam forming the area.

【Example】

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows a barcode league according to an embodiment of the present invention. In the figure, 3 is a laser tube serving as a light source, 6 is a polygon mirror, and 4 is a mirror for changing the optical path. l is a frame that is intermittently rotated by a drive device (not shown);
It is inserted between the light source 3 and the polygon mirror 6. A plurality of lenses 2, 2, . It has become so. The focal length of these lenses 2 is such that the beam diameter is set to, for example, 0 of the barcode size at a position having an appropriate height Hl, 112, . . . from the main body 5 of the device.
．． The lens is narrowed down to the extent that it can be read from 8x to 2x, and a barcode reading area is formed in the vicinity of the aperture, and by making the focal length of each lens 2 different from each other, multiple reading areas are formed. It is designed to be Therefore, according to this embodiment, the beam from the light source 3 is transmitted to any one of the lenses 2 held in the frame 1 which is intermittently rotated at a rotational speed of about 1/10 of the rotational speed of the polygon.
After being narrowed down, the beam is reflected by a polygon mirror 6 to form a scanning beam, which is irradiated to the outside of the apparatus main body 5 through a window 8 . As a result, a plurality of reading areas that change over time are formed on the main body 5 of the apparatus, and the barcode is read by one of the scanning beams. FIG. 2 shows another embodiment of the present invention, in which 4 is a mirror for changing the optical path, and 6 is a polygon mirror. The frame l according to this embodiment is formed into an elongated rectangular shape so that three lenses 2A, 2B, and 2C having different focal lengths are arranged in the horizontal direction as shown in FIG. By reciprocating intermittently, one of the lenses 2 is inserted into the beam optical path. Therefore, according to this embodiment, the beam from the light source 3 is focused by the lens 2 at the upper portions H1, H2, and H3 of the apparatus main body 5, so that three reading areas are obtained.

【Effect of the invention】

As is clear from the above description, according to the barcode reader according to the present invention, a plurality of barcode reading areas are formed on the main body of the device, and by positioning the barcode in one of the areas, the barcode can be read reliably. Since it can be read, the reading area can be substantially expanded.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing another embodiment of the invention, FIG. 3 is a side view thereof, and FIG. 4 is a diagram showing a conventional example. In the figure, 1 is a frame, 2 is a lens, and 3 is a light source.

Claims (3)

[Claims] (1) A plurality of lenses (2A, 2B...) with different focal lengths held in the frame (1) are sequentially inserted into the beam optical path system from the light source (3), and scanning beams with different focal positions are periodically transmitted. Barcode reader that illuminates. (2) The barcode reader according to claim 1, wherein the plurality of lenses (2) are held by a frame (1) that rotates intermittently. (3) The barcode reader according to claim 1, wherein the plurality of lenses (2) are held by a frame (1) that moves back and forth intermittently.