JPS59121473A - Bar-code reader - Google Patents

Abstract

PURPOSE:To simplify the structure of a pen, and to reduce the number of parts and the number of man-hour for assembly by providing a light transmitting part for leading in an external light, on the tip of a housing which slides on a bar- code, and converting an external reflected light from the bar-code to an electric signal by a photodetector provided in the housing. CONSTITUTION:A light transmitting part 11 is fixed to the opening tip of a housing 10 of a cylindrical bar-code reader. Also, a lens 12 photodetector 13 and an amplifying cirlcuit 14 are provided on the inside of the housing 10. This housing 10 is held by hand, the light transmitting part 11 of the tip part is pressed at an almost right angle against a bar-code 8 of a recording medium, and scanning is executed. Subsequently, a reflected light from the bar-code 8 by an external light 16 is condensed to a lens 12 from a tip opening 15 of the light transmitting part 11, converted to an electric signal by the photodetector 13, and the bar-code 8 is read by the amplifying circuit 14. According to this constitution, the structure of a pen of the reader is simplified, and the number of parts and the number of man-hour for assembly are reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION 0) Field of Industrial Application This invention relates to a barcode reader that optically reads barcodes in which various information is encoded.

←), Prior Art With the spread of computer-based equipment in homes, offices, schools, etc., various optical input devices such as barcode readers and light pens have been developed and put into practical use. Barcode readers optically read parboods by pressing the tip of a cylindrical housing called a barcode wand or the like onto a black and white vertical striped barcode printed on paper, etc. and scanning it. It converts the signal into an electrical signal and inputs it to the computer.The pen-shaped housing generally includes a light source to project light onto the barcode, an optical sensor that receives reflected light from the barcode, and a lens to increase sensitivity. system,
A device with a built-in amplifier circuit that amplifies the output of the optical sensor is used.

For example, if we explain a conventional barcode reader using Figure 1,
(1) is a cylindrical pen with an opening at the tip, (2) and (3) are a light source (such as a light emitting diode) and a light sensor (such as a photodiode) installed inside the tip of the pen (1) % + 41 and (5) (6) is a first lens and a second lens arranged at fixed positions in front of the light source (2) and the optical sensor (3), and (6) is an amplifier circuit. Hold the pen (1) in your hand and point the pen tip to the paper (7)
Run the upper barcode °(8)K at an angle of approximately 900 degrees, and focus the light from the light source (2) onto the barcode (8) located at the pen tip aperture (9) using the second lens (4). When the barcode (8) is illuminated, the light reflected by the barcode (8) is reflected by the second lens (
6) and enters the optical sensor (3) where it is converted into an electrical signal. This electrical signal is a kind of pulse signal, the width of the pulse changes depending on the width of the bar (black) and space (white) of the barcode +81, and the intensity is proportional to the reflection coefficient of light in the bar and space. By amplifying this pulse with an amplifier circuit (6) and outputting it to an external computer, etc., the content of the shiver code (8) is read.

A barcode reader incorporating such a light source (2) is not affected by external light and can be used even in a dark place. However, when placing the light source (2) and optical sensor (3) inside the tip of the pen, the lens 141+5 is placed in the optical path on the light emitting side and the light receiving side.
), which inevitably increases the number of parts and complicates the internal structure of the pen. As a result, the pen F1) is inevitably thick and has a poor operating feel, and also requires a large number of assembly steps, and it is difficult to adjust the positions of the optical systems on the light emitting side and the light receiving side, resulting in poor assembly workability. Further, most of the power consumption of the barcode league is due to the light source (2), and in barcode readers using dry batteries, batteries must be replaced frequently, which is uneconomical.

(c), Purpose of the Invention The present invention simplifies the structure of a pen in a barcode league;
The aim is to reduce costs and power consumption by reducing the number of parts and assembly man-hours.

2), Structure of the Invention The present invention was made in view of the current situation where barcode leagues are rarely used in dark places. It is characterized by having a transparent part for introduction. The light-transmitting portion includes a transparent cap or a partial space.

External light transmitted through the light-transmitting part, which is the nib of the housing, hits the bar code and is reflected, enters the optical sensor of the light-receiving element via the lens inside the housing, and is photoelectrically converted. When such external light is used for barcode reading, the strength of the external light becomes a problem, but this problem can be solved by electrical processing in an amplifier circuit, etc., and the light source inside the housing can be omitted. In particular, the light emitting side lens can also be omitted, so that the above object can be easily achieved.

(e) Embodiment In one embodiment of FIG. 2, 1101 is a cylindrical housing. (ti) is a transparent cap coaxially screwed and fixed to the opening tip of the housing. corresponds to 4 to Q4 are lenses, optical sensors, and amplifier circuits installed inside the housing head. Lens ano and optical sensor (1
The optical axis of 31 coincides with the center line of the housing flo).

On day 0 of the lens, a transparent cap (tip opening of 111 (II5
The optical sensor H1C is placed at a position where the light (reflected light) from the optical sensor H1C is focused. The output level of the optical sensor has a large difference because it corresponds to the intensity level of the external light, and therefore, an amplifier circuit is used to vary the barcode reading discrimination level according to this level difference to prevent erroneous detection. For example, as shown in FIG. 8, this means that the bias voltage V of the amplifier circuit is
The output level detection signal m may be used to perform a four-turn operation.

The above barcode reader is used by holding a pen in your hand and scanning it by pressing the tip of the transparent cap (1 tip) against the barcode (8) at an angle of approximately 90 degrees. This use is performed in a place with brightness determined by the sensitivity of the optical sensor (11), and when used, external light H enters from the transparent cap (river) to its tip opening α- and is reflected on the barcode 1g+. , a part of this reflected light passes through the lens (I
The light is focused on the optical sensor ll3) and outputted by the optical sensor Ogl, and the barcode (8) is read at the output of the amplifier circuit. Transparent cap HA: Even when it is away from the barcode (8), some of the external light (l@) enters the α field of the optical sensor through the lens (1"4), but the amount of light at this time depends on the barcode reading system. The amount of light during operation is significantly lower, making it easier to use the optical sensor (
+1 is not output, or even if it is output, it is processed as an insignificant signal by the signal level varying operation of the amplifier circuit 04.

Figure 4 shows another embodiment of the light-transmitting part at the tip of the pen. A ring is formed, and the center of this ring is on the center line of the housing 4, and the bar code (8)
Push it up and scan it. In this case, the external light enters the center of the ring from the space between the housing (the seagull and the ring), is reflected on the barcode in the center of the ring, and is reflected on the barcode at the center of the ring.
Lens in 1111 (enters L field and barcode (8)
reading) is performed. ζ QQ It is used to ensure that the pen body f
If an external means is used as a position regulating means for io+, the bin αη is not necessarily required.

In addition, as a substitute for bottle wars, we use a mesh-like cap with a lot of space, a frame, etc. to eliminate extraneous light! It is also possible to construct a transparent part that introduces II into the pen tip.

(f) Effects of the Invention As described above, according to the present invention, the number of parts inside the housing can be reduced, the internal structure of the housing can be simplified, the pen can be made smaller and thinner, and the number of assembly steps can be reduced. A good barcode reader with good operability can be provided. Furthermore, by omitting the light source, an economical barcode reader with low power consumption can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the tip of a pen of a conventional barcode reader, FIG. 2 is a sectional view of a main part showing an embodiment of the present invention, FIG. The figure is a perspective view of essential parts showing another embodiment of the present invention. (δ)...Barcode, shout...Housing, (11
)...Transparent part (transparent cap), H...Light receiving element (light center), (I4...External light.

Claims (1)

[Claims] (I) A transparent part is provided at the tip of the housing that slides over the barcode to introduce external light, and the external reflected light from the barcode is converted into a stain detection signal by a light receiving element built into the housing. Barcode reader with special features.