JPS60239889A - Pattern identifier - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (a) Technical field of the invention The present invention relates to the configuration of an identification device for identifying paper sheets.

(b) Background of the Technology With the development of information processing devices, pattern recognition devices that automatically identify and count banknotes, securities, cards, etc. have become widespread.

For example, automatic deposit payment machines installed at the counters of financial institutions.
An ATM (abbreviated as ATM) is operated using a porcelain card or a bankbook, and cash payments and deposits are automatically made.

The present invention relates to an improvement of a pattern identification device for automatically identifying paper sheets as described above.

(C) Prior Art and Problems Magnetic methods and optical methods have been put into practical use as methods for identifying banknotes, securities, and the like.

That is, in the magnetic method, a pattern printed using magnetic ink is detected by a magnetic sensor, and in the optical method, the printed pattern is irradiated with light.

Identification is performed using the characteristics of the pattern signal based on the reflected light or transmitted light.

This method uses reflected light for identification, and Figure 1 shows the configuration according to the conventional method (A) and the identification pattern obtained using this method (B).
This shows that.

That is, one light source (for example, a light emitting diode) 1 and two light receivers (for example, photodiodes) 2 and 3 are connected to the object to be measured (
For example, it is provided on a transparent cover 6 installed across a conveyance path 5 for conveying banknotes 4, and a light shielding plate 7 is provided between the light source 1 and the light receiver 2 disposed on the same side. It is already installed.

Here, the light shielding plate 7 is designed to prevent stray light 8 from the light source 1, that is, light tX1.
This is to block the light that enters the light receiver 2 directly or reflected by the transparent cover 6, and also to block the light that enters the light receiver 2 directly or reflected by the transparent cover 6.
detects the object to be measured 4 and adjusts the level so that the light output of the light source always shows a constant value.

In other words, the object to be measured 4 inserted into the window is transported by the heald running at high speed to the identification section consisting of the light source 1 and the light receiver 2.3, but until then most of the light from the light tA1 is transparent. The stray light 8 is detected by the light receiver 3 after passing through the cover 6 and the transport path 5, and since the stray light 8 is blocked by the light shielding plate 7, the light detected by the light receiver 2 is reflected by the transparent cover 6 on the light receiving side. There is only very little light.

FIG. 1(B) shows waveform output fluctuations before and after the object to be measured 4 is detected.

Here, the upper waveform 9 is the detection waveform of the upper light receiver 2 which functions as a pattern identification sensor, while the upper waveform 10 shows the detection waveform of the lower light receiver 3 which functions as a monitor sensor.

That is, until the object to be measured 4 arrives at the lower light receiver 3, a high level of light 11 passes through the transparent cover 6 and the conveyance path 5.
is detected, but a fluctuation correction circuit is provided that feeds the light source 1 so that this output level always shows a constant value.

- Stray light 8 is blocked by the light shielding plate 7 in the sumo wrestler's light receiver 2, and only a small amount of reflected light from the transparent cover 6 on the light receiving side is incident, so only low level light 12 is detected.

Next, when the object to be measured 4 is transported and blocks the optical path to the lower photoreceiver 3, the output of the photoreceiver 3 decreases drastically as shown in the same figure (B), and the photoreceiver 2 on the sumo wrestler side reflects the light. It receives light, and its output level shows an output fluctuation 13 corresponding to the intensity of the pattern drawn on the object 4 to be measured.

Then, when the object to be measured 4 passes, it returns to the original state again.

Next, the identification device is connected to the light receiver 2 and is provided with a comparison circuit, which compares the pre-stored dictionary data with the calculation processing data of the pattern signal from the light receiver 2 to identify the object to be measured. Identification is performed.

Conventionally, patterns were identified in this way.

However, a light shielding plate 7 is required to block the stray light 8, and a light receiver 3 is required to keep the output level of the light source 1 constant, which requires a large number of parts. In order to efficiently receive the reflected light from the object to be measured 4, there is a problem that it takes time to adjust the position of the light receiver 2.

(d) Object of the Invention An object of the present invention is to provide a configuration of an apparatus capable of identifying paper sheets by reflected light with a small number of parts and without requiring complicated adjustments.

(e) Structure of the Invention An object of the present invention is to provide a transparent dust-proof cover in an apparatus that irradiates light onto an object passing on a conveyance path and identifies the pattern of the object based on the reflected light from the object. A detector consisting of a light source and a light receiver is installed on the conveyor path covered with
As soon as the detector detects the object to be measured, the continuous lighting of the light source is changed to a flashing lighting, and a detection mechanism synchronized with the light source,
This can be achieved by a pattern identification device that detects and identifies only the reflected light from the object to be measured.

(f) Embodiments of the Invention The present invention reduces the number of light receivers used, eliminates the light shielding plate, and slices the output of the light receiver using a pre-measured stray light detection level as a threshold. This is to obtain reflected light output.

FIG. 2(A) is a block diagram for explaining the identification method according to the present invention, FIG. 2(B) is a waveform of a light source, and FIG. 2(C) is a detected waveform of a light receiver.

Here, the object to be measured 4 is conveyed at high speed on the conveyance path 5, and the transparent cover 6 is placed above the conveyance path 5, as in the past, but the lower transparent cover 6 is placed directly under the light source 1. It exists only at the position of the round hole provided, and serves as a place where the projected light passes when there is no object to be measured 4.

On the other hand, the light receiver 15 is disposed close to the transparent cover 6, with a gap of two or three fins, for example, and is configured to detect both the stray light 16 from the light source 1 and the reflected light 17 from the object to be measured 4. Take.

The device identification method according to the present invention will be described as follows.

The light source 1 continues until the light receiver 15 detects the presence of the object 4 to be measured, that is, the light source 1 is illuminated by the reflected light 17 from the object 4.
As shown in FIG. 5(B), continuous lighting is continued at a constant output level until the detection level of No. 5 rises rapidly.

Here, most of the light from the light source 1 passes through the transport path 5 and the upper and lower transparent covers 6 and is transmitted directly below, and only the stray light 16 is detected, so the detection level 18 of the light receiver 15 is
) as shown below.

Note that the output level of the light source 1 is always maintained at a constant value by a feedback circuit with the light receiver 15.

Next, when the light receiver 15 detects the object 4 to be measured and the output increases rapidly, the light source 1 automatically switches from the continuous lighting to the intermittent lighting, that is, the blinking 19, as shown in FIG. It will be done.

In this state, the reflected light 17 from the object to be measured 4 is detected by the light receiver 15, but since the light receiving level due to the stray light 16 is known, only the light receiving signal 20 sliced from this level is output, and inside the device. The comparison circuit compares the pattern signals of the object to be measured 4 stored in advance and performs identification.

By doing so, pattern identification can be performed with a simpler configuration than in the past.

FIG. 3 shows a control circuit that performs such identification.

That is, the switch circuit 22 operated by the control circuit 21
Initially, the light source 1 is connected to the continuous lighting drive circuit 23, the light receiver 15 detects only stray light and amplifies it, and the AD converter 24 measures the stray light level and uses it as the darkness value. .

Next, when the object to be measured is transported and the output level of the AD converter 24 exceeds this dark value, the control circuit 21 switches the switch circuit 22, connects the light source 1 to the chop light drive circuit 25, and The output from the photoreceiver 15 is sliced into dark values and detected in a synchronous detection circuit 26, resulting in a photoreception signal 20 shown in FIG. 2(C).

The received light signal 20 is converted into a digital signal by an AD converter 24, and then compared with a pre-stored signal in a comparison circuit for identification.

Note that the variable amplifier 27 changes the amplification degree depending on the darkness value due to stray light and the received light signal.

The above circuit makes it possible to identify paper sheets.

(g) Effects of the Invention The present invention aims to reduce the number of parts and simplify adjustment of a conventional paper sheet identification device, and by implementing the present invention, it is possible to reduce the cost of the device.

[Brief explanation of drawings]

Fig. 1 relates to a conventional identification device, (A) is a block diagram, (B) is a detected waveform, and Fig. 2 is an identification device according to the present invention, (A) is a block diagram, (B) and (C). is the detected waveform, and the third
The figure is a circuit diagram. In the figure, 1 is a light source, 2, 3.15 is a light receiver, 4 is an object to be measured, 7 is a light shielding plate, 8, 16 are stray lights, 13 is output fluctuation, 17 is reflected light, and 20 is a received light signal. * 1 Prisoner (c) (5) Pavilion 3rd

Claims (1)

[Claims] In a device that irradiates light onto an object passing on a conveyance path and identifies the pattern of the object based on the reflected light from the object, a light source and a light source are placed above the conveyance path covered with a transparent dustproof cover. A detector consisting of a light receiver is provided, and as soon as the detector detects the object to be measured, the continuous lighting of the light source is changed to a blinking light, and a detection mechanism synchronized with the light source detects only the reflected light from the object to be measured. A pattern identification device characterized by detecting and identifying waves.