JP2688264B2 - Optical reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] The present invention relates to an optical reading device suitable as a bar code reading device and the like, and is incorporated in a housing for the purpose of improving a reading success rate (first scan rate). The laser beam emitted from the beam scanner irradiates the object existing in the space in front of it while being emitted from a predetermined reading window, and the reflected light is detected to optically read the characteristics of the object. In the reading device, a guide display indicating the optimum reading height and direction of the object to be read is drawn in the space in front of the reading window by using a hologram.

[Industrial applications]

The present invention relates to an optical reading device suitable as a barcode reading device and the like.

Conventionally, in an optical reading device used as a barcode reading device or the like, since there is no instruction about the position (height direction) with the highest reading rate, the operator does not always read the object to be read at the optimum position. However, there is a problem that the read object is read at a position where the reading rate decreases depending on the orientation of the barcode surface.

For this reason, there is a demand for designating a position (height direction) where the reading rate is the highest and improving the reading success rate.

[Conventional technology]

FIG. 5 is an external perspective view showing a conventional bar code reader which is an example of this type of optical reader.

As shown in FIG.
Irradiates a laser beam 3 emitted from a beam scanner (not shown) built in the housing 2 onto an object existing in the front space while emitting the laser beam 3 from a predetermined reading window 4 and detects the reflected light thereof By doing so, the feature of the object is read.

In such a barcode reading apparatus 1, the optimum reading height and direction are usually set in a certain height range from the window surface 4a of the reading window 4, and the object passing from this height range and direction is set. If the position deviates, the reading success rate (first scanning rate) may decrease depending on the direction of the barcode surface.

It should be noted that the height range that allows this reading, that is, the depth of field is generally limited by the beam diameter of the laser beam.

In the conventional barcode reader 1 of this type,
As shown in the figure, an arrow figure 5 indicating the passing direction of the object to be read is printed on the window surface 4a of the reading window 4, for example, to guide the operator to indicate the passing direction of the object to be read.

[Problems to be solved by the invention]

However, in the case of such a conventional guide display using the arrow graphic 5 on the window surface 4a, it is possible to accurately guide the passing direction of the object to be read, but to guide the passing height at all. For this reason, some operators do not read an object to be read (such as a product with a barcode) at an optimum position (height direction), which causes a problem that reading may fail.

The present invention has been made in view of the above problems, and an object thereof is to improve a reading success rate (first scan rate) in an optical reading apparatus of this type.

[Means for solving the problem]

In order to achieve the above-mentioned object, the present invention irradiates an object existing in the space in front of the laser beam emitted from a beam scanner incorporated in the housing and emits it from a predetermined reading window, and reflects it. In a bar code reading device that reads the characteristics of the object by detecting light, a hologram is displayed in a space at a predetermined distance in front of the reading window and a guide display showing the optimum reading height and direction of the object to be read. It is characterized by using and drawing.

[Action]

With such a configuration, the optimum reading height and direction can be accurately guided to the operator. Therefore, the operator moves the object to be read according to this guide display to reduce the reading failure, and the reading success. The rate can be improved.

〔Example〕

FIG. 1 is a perspective view showing the external appearance of an embodiment of a bar code reading apparatus according to the present invention.

In the figure, a laser light source, an optical system using a lens,
A Lippmann hologram 7 is attached to the upper surface of the housing 6 having a built-in rotating mirror and the like, that is, the reading window surface.

As is well known, such a Lippmann hologram 7 is
As shown in FIG. 4, a dry plate 7b coated with emulsion 7a is prepared, and the object light 7c is arranged in the arrangement shown in the drawing.
And the reference light 7d.

A column 8 is erected on the side of the housing 6, and an illumination lamp 9 for irradiating the hologram 7 with reference light 10 is mounted on the column 8.

According to the above configuration, when the reference light 10 is irradiated from obliquely above, the optimum passing height of the object to be read is stored in the space having a height of about 10 cm on the housing 6 as shown in FIG. Since the arrow figure 11 indicating the size and the direction is drawn, as long as the object to be read is moved according to the instruction by the arrow figure 11,
The operator can surely read the barcode attached to the object through the laser beam 12.

 FIG. 2 is a diagram showing a second embodiment of the present invention.

As shown in the figure, in this example, the housing 6 is vertically mounted on the checkout counter 13.

 FIG. 3 is a diagram showing a third embodiment of the present invention.

As shown in the figure, in this example, the L-shaped arm 15 is projected from the side of the housing 6, and the illumination lamp 14 is attached to the upper end thereof.

With such a configuration, the housing 6 can be easily moved and installed.

As described above, according to the above-described embodiment, as long as the object to be read is moved according to the arrow figure 11 displayed in the space, the operator can surely read the bar code attached thereto.

In the above embodiment, the arrow figure is shown as the guide figure showing the optimum passing height and direction of the object to be read, but it is needless to say that any other figure can be adopted.

Also, the type of hologram is not limited to the Lippmann hologram, and any reflection type or transmission type can be adopted.

〔The invention's effect〕

As is clear from the above description, according to the present invention, the optimum position (height direction) can be designated for the operator, thereby improving the reading success rate (first scan rate) in this type of optical reading device. be able to.

[Brief description of the drawings]

 FIG. 1 is a block diagram of the first embodiment of the present invention, FIG. 2 is a block diagram of the second embodiment of the present invention, FIG. 3 is a block diagram of the third embodiment of the present invention, and FIG. FIG. 5 is a diagram showing a method of creating a hologram, and FIG. 5 is a conventional configuration diagram. 6 …… Case 7 …… Lippmann hologram 8 …… Staff 9 …… Illumination lamp 10 …… Reference light 11 …… Arrow figure 12 …… Laser beam 13 …… Checkout counter 14 …… Illumination lamp 15 …… L-shaped Shaped arm

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Fumio Yamagishi 1015 Uedanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Hiroyuki Ikeda 1015 Kamikodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (1)

(57) [Claims] 1. A laser beam (12) emitted from a beam scanner incorporated in a housing (6) is emitted from a predetermined reading window while irradiating an object existing in the space in front of the laser beam (12), and its reflected light is reflected. In the optical reading device (1) that detects the characteristics of the object by detecting, a guide display (11) indicating the optimum reading height and direction of the object to be read is provided in the space in front of the reading window. An optical reader characterized by drawing using a hologram (7).