JPS6126996Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical symbol reading device that optically reads information display symbols printed on articles.

Optical symbol reading devices currently used in POS (Point of Sale) systems have an appearance as shown in Figure 1, with an opening 1 including a radiation window.
has a cross section as shown in Figure 2a.
That is, the deflected scanning beam 2 scans the article 3 through an aperture 1 having a window 4 made of a transparent medium, and scans an information marking code printed on the surface of the article or on a label affixed to the article. It receives the reflected light from the sensor, processes the signal, and reads the signal.

In this case, the problem is deterioration in reading performance due to scratches and dirt on the radiation window made of a transparent medium.
This is caused by scattering or absorption of light by scratches and dirt. The scratches occur because the object comes into contact with the radiation window when it approaches the radiation window and passes through the reading area.
Or because it wipes away dirt. Most of the stains are caused by the falling moisture contained in the item itself or the adhesion of fingerprints.

One way to reduce these problems is to remove windows made of transparent media, but since the reading device is an optical machine, contamination of the optical components by objects falling from the windowless opening will immediately deteriorate the performance. Removal of the window is not possible as it would lead to To reduce only the susceptibility to damage, there is a structure shown in FIG. 2b or 2c. In FIG. 2b, a guard plate 5 with a hole is prepared so that the scanning beam 2 can pass through, and
With transparent medium 4 placed underneath, Figure 2c
In both cases, the transparent medium 4 is placed lower than the substrate 6 that forms the surface on which the article slides, preventing the article from coming into direct contact with the medium 4. It is. However, although these structures can reduce scratches, they cannot be expected to be effective against stains.

The present invention eliminates these drawbacks of the conventional ones and provides a structure that has a remarkable effect on both scratches and dirt.According to the present invention, light is deflected,
In an optical symbol reading device that scans a symbol to be read through an opening having a radiation window made of a transparent medium and reads the symbol by receiving reflected light from the symbol to be read, the radiation window is connected to the opening. An optical symbol reading device is obtained, which is characterized in that it is placed apart from directly below.

The following is a description of an embodiment of the present invention with reference to the drawings.
In both cases, the transparent medium 4 is placed away from directly below the opening 1. In this case, indirect dirt caused by the falling object bouncing off the retaining plate 7 can be reduced by placing an absorbent medium 8 such as felt as shown in Fig. 3c.

According to the present invention, it is possible to provide stable reading over a long period of time without causing scratches due to contact with the object to be read, as well as stains due to direct adhesion of fallen objects such as liquids. .

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the external appearance of the optical symbol reading device, Fig. 2 a, b, and c are cross-sectional views showing the configuration of the conventional aperture, and Fig. 3 a, b, and c are the apertures of the embodiment of the present invention. FIG. DESCRIPTION OF SYMBOLS 1... Opening, 2... Scanning beam, 3... Article, 4... Transparent medium, 5... Guard plate, 6... Substrate, 7... Holding plate, 8... Absorptive medium. 〓〓〓〓〓

Claims (1)

[Scope of utility model registration request] An optical symbol reading device that reads a symbol by deflecting light, scanning a symbol to be read through an opening having a radiation window made of a transparent medium, and receiving reflected light from the symbol to be read. An optical symbol reading device characterized in that a window is placed outside the opening directly below the opening.