JPS6145555Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an optical information reading device, in particular, a device that irradiates a light beam onto an object on which information is written (hereinafter simply referred to as the object), and receives the reflected light using a photodetector. The present invention relates to an optical reader that obtains electrical signals corresponding to information.

Optical information reading device For example, a device that displays desired information on a label as a barcode, scans the label with light, converts the reflected light into an electrical signal with a photodetector, and reads the information using a signal processing circuit. This has already been proposed, and the configuration diagram is shown in Figure 1.

In FIG. 1, 1 is a laser light source, and 2 is a hologram disk (hologram scanner).
3... is irradiated.

It is well known that when a rotating hologram disk is irradiated with a light beam, the diffracted light scans the object, and the label 3 on which information is written is scanned by the diffracted light.

The reflected light from the label 3 is focused on the photodetector 4 by the focusing hologram forming areas b1, b2, . . . .

Reference numeral 5 denotes a signal processing circuit which receives the output signal from the photodetector 4, performs predetermined signal processing, and reads the information written on the label.

M is a motor that rotates the hologram disk 2.

6 is an article with a label attached, 7 is a glass plate 7
The article slides on the surface of the counter 7 into which a is fitted.

By the way, the label 3 is usually affixed to products, and when a large number of products are handled, a person holds the product with the label 3 affixed by hand, and the glass plate 7a is removed to expose the label 3 to the irradiation beam. Slide it on the inset counter.

However, since the glass plate 7a is fitted into the counter 7, the glass plate 7a is easily scratched when the product is slid.As shown in FIG. The recessed glass plate 7a and the sliding surface form a constant plane angle.

However, with such an optical information reading device, it is necessary to carry the article into a spatial area that is irradiated with the scanning light beam from the laser scanner 2 (that is, a spatial area where information can be read), but conventionally, an operator cannot read this information. It economically recognized the reading area and read information on labels affixed to articles.

However, the information reading area is located in a specific space above the exit window of the scanning light beam, and it is difficult to maintain the reading area due to the window position and shape.

Therefore, when reading a large number of items, it is difficult to bring the items with labels firmly affixed to the information reading area into the information reading area, and reading errors may occur, requiring the operator to repeat the reading operation for the same item again. This resulted in a decrease in work efficiency.

The present invention was developed in view of the above, and an object of the present invention is to provide a novel optical information reading device that displays a spatial area in which information can be read, in order to improve operability for the operator.
A means for scanning the object with the laser beam while irradiating the object with information written thereon is provided, the object is scanned by the laser beam from the laser beam scanning means, and the information is detected from the reflected light. In an optical information reading device configured to perform reading, a means for projecting a visible light beam is provided, and information can be read by projecting the visible light beam from the visible light beam projecting means onto a spatial region where the laser beam scans the object. The feature is that the spatial area is clearly indicated.

With this configuration, it is possible to clearly indicate whether or not an object exists within a readable spatial region without affecting the laser beam that reads information on the object, and stable reading of the object is possible. can be realized.

Preferred embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 shows a cross section of essential parts of the optical information reading device according to the present invention, and the same parts as in FIG. 1 are given the same reference numerals.

In FIG. 2, F is an interference filter,
It has high transmittance for red light and high reflectance for light of other wavelengths.

W is a white light source, R is a concave mirror, L is a condensing lens N is a light beam shaping mask provided with a rectangular aperture A.

Next, the operation of the apparatus shown in FIG. 2 will be explained.

White light from a white light source W is reflected directly or by a concave mirror R, condensed by a condensing lens L, shaped by a mask N, and enters an interference filter F as a rectangular beam. In this case, only red light is transmitted, and light of other wavelengths is reflected and travels toward the sliding surface of the counter 7.

In Fig. 2, H ₁ and H ₂ are the interference filters F
The spatial region S surrounded by the light rays H ₁ and H ₂ becomes the information reading region.

On the other hand, the red laser light from the laser light source 1 enters the laser scanner 2, and the laser beam output from the laser scanner 2 becomes a scanning light, as described in connection with FIG.

In the case of this embodiment, the scanning light from the laser scanner 2 that has passed through the interference filter F enters the information reading area S described above.

Therefore, as long as the article 6 to which the label 3 is affixed has been moved on the sliding surface of the counter 7 by the operator and is carried into the label reading area S,
The label 3 affixed to the article 6 is irradiated with scanning light from the laser scanner 2 .

Whether or not the article 6 has been carried into the information reading area S is output from the white light source W, and is output from the interference filter F.
Since the operator can visually confirm that the light reflected by the article 6 is reflected by the article 6, it can be easily determined.

The scanning light reflected from the label 3 of the article 6 passes through the interference filter F and passes through the laser scanner 2.
, and is focused on the photodetector 4 by the focusing hologram as described in connection with FIG.

The photodetector 4 converts the signal into an electrical signal corresponding to the label information, and the signal is led to the reading circuit 5, where the label information is read.

In the above-mentioned embodiment, the interference filter had the characteristic of transmitting only red light, but of course it may have a high transmittance for light of other wavelengths corresponding to the scanning light wavelength. is clear.

As is clear from the above description, in the optical information reading device according to the present invention, the information reading area is clearly indicated, making it easier for the operator to read the information, and the visible light beam clearly indicating the area is a scanning laser beam for information reading. It is possible to improve work efficiency and achieve stable reading without affecting the image quality.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional optical information reading device, and FIG. 2 is a configuration diagram of an embodiment of the optical information reading device according to the present invention. 1: Laser light source, 2: Hologram disk,
3: label, 4: photodetector, 5: reading circuit,
6: Goods, 7: Counter, F: Interference filter,
W: white light source, L: condensing lens, N: mask,
R: Concave mirror.

Claims (1)

[Scope of utility model registration request] A means for scanning the object with the laser beam while irradiating the object with information written thereon is provided, the object is scanned by the laser beam from the laser beam scanning means, and the information is detected from the reflected light. In an optical information reading device configured to perform reading, a means for projecting a visible light beam is provided, and information can be read by projecting the visible light beam from the visible light beam projecting means onto a spatial region where the laser beam scans the object. An optical information reading device characterized in that it is configured to clearly indicate a spatial region.