JP3035415B2 - 2D code scanner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable two-dimensional code scanner for reading information of a two-dimensional code such as a multi-stage bar code or a matrix code printed on a print medium.

[0002]

2. Description of the Related Art Generally, for example, POS (point of sale)
s) When registering product information in a system, etc.,
A label printed with a bar code obtained by encoding the product information as shown in FIG. 10A is attached to the product, and at the time of sale, the bar code on the label is read by a bar code scanner to obtain the product information. Was to be registered.

As a bar code scanner, for example, FIG.
Touch bar code scanner 1 shown in FIG.
Gun type bar code scanner 2 shown in FIG.
A fixed barcode scanner 3 shown in FIG.

The touch-type bar code scanner 1 uses an apparatus by hand, is formed at the tip of the apparatus, and has an LED (ligh).
t emitting diode) light emitting unit and multiple Cs arranged in a row
The reading unit 1a composed of a CD (charge coupled device) element is brought into close contact with the barcode printed on the label, and the code reading switch 1b is turned on so that the LE is turned on.
The LED of the D light emitting section emits light to irradiate the bar code, and reflected light from the bar code generated by the irradiation is applied to each CCD.
The bar code is read by receiving light by the element. When the reading of the bar code is completed normally, the reading completion lamp 1c formed of an LED provided on the upper surface of the apparatus is turned on.

The gun type bar code scanner 2 uses the apparatus by hand, and has a reading section 2a formed of a laser emitting section and a CCD element formed at the upper front of the apparatus.
By bringing the reading unit 2a close to the label and turning on the code reading switch 2b, the laser beam from the reading unit 2a scans the bar code printed on the label,
The reflected light is received by a CCD element to read a bar code.

Further, the fixed bar code scanner 3 is
The apparatus is fixedly installed at a predetermined position for use, and a reading section 3a composed of a laser emitting section and a CCD element is formed on the front of the apparatus. Scans a barcode printed on a label, and receives the reflected light by a CCD element to read the barcode.

Each of the bar code scanners described above is connected to a host computer that processes product information via a connection cable or the like, and outputs the read bar code information to the host computer via the connection cable or the like. The host computer registers the product information based on the input barcode information.

[0008] As described above, the fields in which registration processing and the like of article information and information management and the like are performed using bar codes or the like obtained by coding predetermined information have spread to FA (factory autometion), distribution, and service industries. The types of information to be handled are also diverse, and tend to require large amounts of information.

Therefore, as the information amount increases, the information density that can be coded becomes insufficient because the information density of a single bar code is low. Therefore, in order to increase the information density and cope with the increase in the amount of information, a multi-stage barcode shown in FIG. 10B and a two-dimensional code shown in FIG. 10C have been developed.

As a device for reading such a multi-stage bar code or a two-dimensional code, a TV (television) camera type two-dimensional code scanner as shown in FIG. 12, for example, is conventionally known. The TV camera type two-dimensional code scanner is connected to the TV camera 11 via a connection cable, and is connected to a host computer for processing information via a line (RS-232C line). It comprises an image processing device 12 and a TV monitor 13 connected to the image processing device 12 by a connection cable.

In such a TV camera type two-dimensional code scanner, the TV camera 11 is set so as to face the surface of the label 14 affixed to the article on which the two-dimensional code is printed, and under normal room lighting. The two-dimensional code on the label 14 is photographed by the TV camera 11, and the image data obtained by the photographing is processed by the image processing device 12 to be converted into two-dimensional code information. This two-dimensional code information is transmitted to the host computer via the line. On the other hand, the captured image data is output to the TV monitor 13 via the connection cable as it is, and the captured image is displayed on the TV monitor 13.

[0012]

As described above, as a conventional device for reading a two-dimensional code, the above-described two-dimensional code scanner of a TV camera system is known. However, the TV camera 11, the image processing device 12, and the TV The device for the monitor 13 is required, and there is a problem that the whole device is large in weight and shape and expensive.

The label 1 faces the TV camera 11.
4 is set perpendicular to the optical path, and the focus of the TV camera 11 needs to be adjusted according to the distance between the TV camera 11 and the label 14. The TV camera 11 can be adjusted according to the brightness of indoor lighting. For example, there is a problem that it takes time to perform a setup before reading a two-dimensional code, such as adjusting the aperture of the camera.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a two-dimensional code scanner which is small, lightweight and inexpensive, and which can easily and accurately read a two-dimensional code in a short time.

[0015]

SUMMARY OF THE INVENTION The present invention comprises a reading portion and a grip portion provided on an integrally molded portable frame, and the reading portion comes into close proximity to or close to the reading portion. A light emitting unit for irradiating the two-dimensional code attached to the medium with light, and reflected light angle conversion means for refracting or reflecting the reflected light from the two-dimensional code irradiated with the light from the light emitting unit to the grip unit. The grip portion is provided with at least two two-dimensional reading members having a structure in which solid-state imaging devices that receive reflected light from the two-dimensional code and output an electric signal corresponding to the amount of reflected light are two-dimensionally arranged. Means and a solid-state imaging device for each of the two-dimensional reading means for reflecting reflected light incident on each of the two-dimensional reading means via a reflected light angle conversion means from a two-dimensional code on a medium which is close to or close to the reading unit. Lens to form an image at the position , A semi-transparent mirror that splits the light from the optical system mechanism into two-dimensional reading means, and an electric signal output from each two-dimensional reading means. Image information converting means for converting the image information into two pieces of image information, code information analyzing means for analyzing code information of a two-dimensional code from the image information from the image information converting means, and code information obtained by the analysis of the code information analyzing means. And code information output means for outputting the information to an external device.

[0016]

In the present invention having such a configuration, when the reading section of the apparatus is brought into close proximity to or near the two-dimensional code attached to the medium, light from the light emitting section is irradiated on the two-dimensional code. . The reflected light from the two-dimensional code is refracted or reflected by the reflected light angle conversion means to the grip portion, divided into two parts via the optical system mechanism and the semi-transparent mirror, and divided into two parts by the solid-state image sensor of each two-dimensional reading means. An image is formed at the position.

Each solid-state image sensor of each two-dimensional reading means outputs an electric signal corresponding to the amount of reflected light formed by the optical system mechanism, and the image information converting means converts the electric signal into one. Convert to image information.

Here, the code information analysis means analyzes the code information from the image information converted by the image information conversion means, and the analyzed code information is output to the external device by the code information output means.

[0019]

An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to a two-dimensional handy scanner. FIG. 1 is a perspective view of the two-dimensional handy scanner, and FIG. 2 is a sectional view of the two-dimensional handy scanner.

A frame 21 has a hollow structure made of a plastic material or the like. One end has an opening having a small opening area, and the other end has an opening having a large opening area as a reading section 22. A connection cable 23 composed of a power line and a signal line is inserted into a small opening at one end of the frame 21.
Fixed to 1. An LED is embedded in the upper part of the frame 21 as a scan display LED (light emitting diode) 25, and a code reading operation for starting reading of a two-dimensional code is performed on a side surface of the frame 21. A switch 26 is provided.

A portion of one end of the frame 21 on which the small opening is formed is a grip portion. The central axis is at least greater than 90 ° with respect to a vertical line of the printing surface of the two-dimensional code, and
It is formed to be about 10 °.

In the inside of the reading section 22, which is a large opening at the other end of the frame 21, an LED and this L
A plurality of LED light-emitting units 27 as light-emitting units each including a diffusion lens formed of a plastic material that uniformly diffuses light from the ED are arranged in a circular shape or a regular polygonal shape close to a circle. Further, further inside the reading unit 22, an angle conversion mirror 28 as a reflected light angle changing unit is installed at a predetermined angle with respect to the direction of the reading unit 22. Although the angle conversion mirror 28 is used here, a prism may be used instead.

A circuit portion 29 electrically connected to the connection cable 23 and a first portion as a two-dimensional reading means are provided inside the handle portion having a small opening at one end of the frame 21. 2D CCD (charge coupled dev
ice) 30a and a second two-dimensional CCD 30b.

The circuit section 29 is composed of a power supply interface circuit, a display LED / buzzer control section for controlling the scan display LED 25 and a buzzer described later, a CPU (central processing unit) constituting a control section main body, and various memories. It comprises a main control unit, a decoding unit, a code image processing circuit, an imaging signal processing circuit, and the like.
The circuit section 29 has a multilayer board structure, and is formed by mounting chip components constituting each circuit on one or both sides of each board.

The first two-dimensional CCD 30a and the second two-dimensional CCD 30b are electrically connected to the circuit section 29, respectively, and correspond to the transmission surface and the reflection surface of a half mirror 31 as a semi-transparent mirror. Then, the CCD element has a matrix shape (the number of effective pixels is 250,000 pixels, and the number of effective pixels is 4
(0,000 pixels or more). Although the CCD element is used here, another type of solid-state imaging element may be used instead.

The half mirror 31 is provided so as to receive the reflected light from the angle conversion mirror 28. The half mirror 31 and the angle conversion mirror 28 sequentially reduce the amount of transmitted light. An aperture mechanism 32 for adjustment, a combination lens 33, and a filter 34 for reducing unnecessary extraneous light are arranged.

The half mirror 31 is connected to the aperture mechanism 3
2. The reflected light incident through the combination lens 33 and the filter 34 is converted into a first two-dimensional CCD 30a.
And the direction of the second two-dimensional CCD 30b are divided into two by transmission and reflection.

The focus of the combination lens 33 is a contrast that enables binarization of the two-dimensional code when a printing medium such as a label on which a two-dimensional code is printed approaches the reading unit 22 within 10 mm. Has been adjusted as follows.
That is, the two-dimensional code is clearly imaged at the respective positions of the two-dimensional CCDs 30a and 30b by the reflected light via the half mirror 31.

Although the combination lens 33 is used here, this is for minimizing the distortion generated in the received image, and an aspherical lens capable of minimizing the distortion may be used instead. Further, the combination lens 3
If the occurrence of ghost due to reflection on the lens surface poses a problem in 3, the lens surface may be treated with an anti-reflection coating or the like.

The combination lens 33 and the filter 3
4 constitutes the optical system mechanism.

The circuit section 29 is electrically connected to the scan display LED 25 and the code reading switch 26, and is also electrically connected to a buzzer 35 provided inside the frame 21. .

FIG. 3 is a block diagram showing a main circuit configuration of the circuit section 29 of the two-dimensional handy scanner. EEP in which program data and various initial setting data of processing performed by the CPU 41 constituting the main control unit are stored.
ROM (electrically eras-able programmable read a
ccess memory) 42, a DRAM (dy memory) in which various memory areas used when the CPU 41 performs processing are formed.
namice random accessmemory) 43, a mask ROM storing a read format corresponding to each type of registered (attached) two-dimensional symbol (two-dimensional code)
(Read only mem-ory) 44, a decode circuit (decode G) for converting the read image data into code data based on the read format from the mask ROM 44.
A (gatearray) 45 and a serial I / F (interface) 46 connected to an external information processing apparatus such as a host computer via a serial line are connected to the CPU 41 via a system bus 47.

Further, the above-described code image processing circuit 48,
The first two-dimensional CCD 30a and the second two-dimensional C
The two-dimensional CCD 30 is controlled while controlling the CD 30b.
a, the aforementioned imaging signal processing circuit 49 for amplifying the signals from 30b, and the aforementioned LED 27 of the LED light emitting section 27
a light source driver 50 for driving and lighting the light source a, an input / output (I / O) port 51 for inputting an output signal from the code reading switch 26 and outputting a driving signal to the buzzer 36 and the scan display LED 25, respectively.
Are respectively connected to the CPU via the system bus 47.
41.

Therefore, in the circuit section 31, the display LED / buzzer control section is constituted by the I / O port 52, and the main control section is constituted by the CPU 41, the EEPR.
It comprises an OM 42, a DRAM 43 and a serial I / F 46, and the decoding section comprises the mask ROM and a decoding circuit 45.

The image signal converting circuit 49 and the code image processing circuit 48 constitute an image information converting means, and the mask ROM 44 and the decoding circuit 45 constitute a code information analyzing means.
6 constitutes code information output means.

As shown in FIG. 4, the code image processing circuit 48 converts an image signal (each pixel signal) from the image signal processing circuit 49 into an A / D (analogue / d) signal.
(igital) conversion circuit 48a, a frame memory 48b in which the digital data from the A / D conversion circuit 48a is binarized by a preset threshold value, and image data is mapped by the binarized data, and the frame memory 48b. After processing such as density correction, enhancement processing, and smoothing is performed on the image data mapped on the memory 48b, the image data including only the two-dimensional code is extracted, and the extracted image data is rotated and features are extracted. And an image processing circuit 48c for converting the data into regular two-dimensional code image data. And the A
/ D conversion circuit 48a, the frame memory 48b, and the image processing circuit 48c
7 is connected.

Further, the imaging signal processing circuit 49 is provided as shown in FIG.
The first signal processing circuit 49a is connected to the system bus 47 and receives and amplifies an output signal from the first two-dimensional CCD 30a, and is connected to the system bus 47 as shown in FIG. A second signal processing circuit 49b for inputting and amplifying an output signal from the second two-dimensional CCD 30b;
b. Read only memory (ROM) in which information on the variation (defect) of each CCD element caused by each manufacturing factor is stored.
ory) 49c, a defect correction circuit 49d for correcting the reading timing of each CCD element based on the information stored in the ROM 49c, and a shutter for setting the reading time when the printing medium on which the two-dimensional code is printed is a moving body. A control circuit 49e, a timing generation circuit 49f for generating a read timing based on signals from the defect correction circuit 49d and the shutter control circuit 49e, and a two-dimensional image generation method based on the read timing generated by the timing generation circuit 49f. In the CCDs 30a and 30b, a vertical driver 49g and a horizontal driver 49h for respectively specifying the CCD elements to be read, and the signal processing circuits 49a and 4
A synchronizing signal circuit 49i controls the timing of inputting image signals from the two-dimensional CCDs 30a and 30b based on the read timing generated by the timing generating circuit 49f.

FIG. 6 shows a flowchart of the reading process performed by the CPU 41.

First, the system enters a standby state until the code reading switch 26 is turned on.
Is turned on, the LED 27a of the LED light emitting section 27 is turned on.
Is turned on by turning on electricity.

Next, as the processing of step 1 (ST1), the first two-dimensional CCD 30a and the second two-dimensional CCD 30a
The reading operation is started by controlling 30b by the imaging signal processing circuit 49. The image signal read and amplified by each of the two-dimensional CCDs 30a and 30b is binarized by the code image processing circuit 48 and transferred to the frame memory 48b. Here, the binarized data of the imaging signals of the two-dimensional CCDs 30a and 30b are combined and mapped as one image data in the frame memory 48b (symbol combination). The image data of only the two-dimensional code is cut out from the mapped image data, and various code image processing is performed on the cut-out image data of only the two-dimensional code to convert the image data into regular two-dimensional code image data.
43.

The normal two-dimensional code image data stored in the DRAM 43 is transferred to the decoding circuit 45, and a decoding process for converting the two-dimensional code image data into two-dimensional code data is performed using the mask ROM 44.

Here, the decoding process is completed normally (OK).
It is determined whether or not it has been done. If the decoding process does not end normally, that is, if it cannot be converted into two-dimensional code data, the process returns to the above-described step 1 again. If the decoding process ends normally, LE
The power supply to D27a is stopped to turn off the light, and the completion of reading is displayed by turning on the scan display LED 25, or the buzzer 35 is operated to notify the user.

Next, the two-dimensional code data obtained by the decoding process is connected to the connection cable 24 by the serial I / F 46.
Via the host computer or the like, and when the transmission of the two-dimensional code data is completed, the process returns to the first processing of the reading processing again.

In this embodiment having such a configuration, in order to read the two-dimensional code printed on the print medium by the two-dimensional code scanner, first, the two-dimensional code on the print medium is read by the two-dimensional code scanner. The code reading switch 26 is turned on by approaching the unit 22. At this time, the LED light emitting unit 27 is turned on, and the LED light emitting unit 27 is turned on.
Is applied to the two-dimensional code on the print medium, and the reflected light from the two-dimensional code is reflected by the angle conversion mirror 28 in the direction of the half mirror 31. The reflected light is reduced in extraneous light by the filter 34, is divided by the combination lens 33 through the aperture mechanism 32, and is divided into two vertical directions by the half mirror 31, and is divided into the first two-dimensional CCD 30.
a and an image is formed at the position of the second two-dimensional CCD 30b.

Here, the formed reflected light is a two-dimensional CC
Each of the CCD elements D30a and 30b converts the electric signal into an electric signal of a voltage level corresponding to each received light amount. This electric signal is amplified at a predetermined timing by the imaging signal processing circuit 49, and the two-dimensional CCD 30a, 30
The image signal is transferred to the code image processing circuit 48 as two image signals corresponding to b.

The code image processing circuit 48 combines the two image pickup signals into one image data on the frame memory,
Image data of only the two-dimensional code portion is cut out from this image data, and various kinds of code processing are performed on the cut-out image data of only the two-dimensional code portion to convert it into regular two-dimensional code image data.

This regular two-dimensional code image data is DR
The decoding circuit 45 decodes the two-dimensional code based on the format of the type of the two-dimensional code stored in the AM 43 and stored in the mask ROM 44, and outputs the two-dimensional code data to a host computer or the like via the connection cable 24. You.

Since the image is read as described above, for example, as shown in FIG. 9, even if one two-dimensional CCD cannot read all the desired images, as shown in FIG.
The two two-dimensional CCDs 30a and 30b can read different partial images and combine the partial image data as shown in FIG. 8 to read the entire target image.

That is, the two two-dimensional CCDs 30a, 3
0b is arranged at a position where the light split into two by the half mirror 31 forms an image, and further, the first two-dimensional CCD 30a moves in the direction of the tip of the arrow image formed from the center of the image. The second two-dimensional CCD 30b is displaced in the rearward direction in the image of the formed arrow.

Accordingly, the image shifted by the first two-dimensional CCD 30a in the direction of the tip of the arrow and the second two-dimensional CCD 30
By combining with the image shifted in the rear end direction of the arrow by b,
The whole image of the arrow.

As described above, according to the present embodiment, the reading unit 22 of the frame 21 formed integrally with the LED light emitting unit 27 for irradiating the printing medium on which the two-dimensional code is printed with light and the two-dimensional code are used. An angle conversion mirror 28 for reflecting the reflected light in the direction of the grip portion, a combination lens 33 for forming an image of the reflected light from the angle conversion mirror 28 at a predetermined position on the grip portion of the frame 21, and this combination lens A half mirror 31 for splitting the reflected light from the mirror 33 in two directions, and two two-dimensional CCDs 3 arranged at different image positions at positions where the reflected light split by the half mirror forms an image.
0a, 30b, and a circuit unit 29 for generating image data based on the electric signals output from the two-dimensional CCDs 30a, 30b, analyzing the image data, and outputting the two-dimensional code data to the connection cable 23. Thus, the apparatus for reading a two-dimensional code can be configured to be small, lightweight, and inexpensive. Furthermore, since the reading unit 22 of the present apparatus approaches the printing medium on which the two-dimensional code is printed to perform reading, there is no need to adjust the focus or adjust the aperture by changing the illumination for irradiating the printing medium with light. By simply turning on the code reading switch 26, the reading operation is automatically performed, so that the two-dimensional code can be easily read in a short time.

When a single two-dimensional CCD cannot read the entire image, for example, when reading a bar code that is out of specification, a method for reading the entire target image is as follows.
Wide effective area (using more CCD elements)
There is a method using a two-dimensional CCD, or a method of adjusting the magnification of a lens so that an image is contained in an effective imaging area of the two-dimensional CCD. However, the former method has a problem that a two-dimensional CCD having a wide imaging effective area is expensive, and the latter method has a problem that resolution is reduced.

In this embodiment, two inexpensive two-dimensional CCDs 30a and 30b and two
a and 30b are each provided with a half mirror 31 for dividing the reflected light from the two-dimensional code into two.
0a, 30b to partially read an image,
By synthesizing one image data according to 9, even if all images cannot be read by one two-dimensional CCD,
The two-dimensional code can be read without increasing the cost as much as possible and without lowering the resolution. This is particularly effective for rectangular codes such as long bar codes.

[0054]

As described in detail above, according to the present invention,
It is possible to provide a two-dimensional code scanner which can be configured to be small, lightweight and inexpensive, and which can easily and accurately read a two-dimensional code in a short time.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing the embodiment.

FIG. 3 is a block diagram showing a main circuit configuration of the embodiment.

FIG. 4 is a block diagram showing a circuit configuration of the code image processing circuit of FIG. 3 of the embodiment.

FIG. 5 is a block diagram showing a circuit configuration of the imaging signal processing circuit of FIG. 3 of the embodiment.

FIG. 6 is an exemplary view showing the flow of a reading process of the embodiment.

FIG. 7 is an exemplary view for explaining reading of a non-standard two-dimensional code according to the embodiment;

FIG. 8 is an exemplary view for explaining composition of image data in reading a non-standard two-dimensional code according to the embodiment.

FIG. 9 is a view for explaining reading of a non-standard two-dimensional code by one two-dimensional CCD.

FIG. 10 is a diagram showing examples of various codes.

FIG. 11 is a perspective view showing an example of various barcode scanners of a conventional example.

FIG. 12 is a perspective view showing an example of a conventional two-dimensional code scanner.

[Explanation of symbols]

21 ... frame, 22 ... reading unit, 27 ... LED light emitting unit,
28 ... Angle conversion mirror, 29 ... Circuit part, 30a, 30b ... 2
Dimensional CCD, 31: half mirror, 33: combination lens.

Claims (1)

(57) [Claims] 1. A reading part and a grip part provided on a portable frame integrally molded, wherein the reading part is attached to a medium close to or close to the reading part. A light emitting unit for irradiating light to the two-dimensional code, and reflected light angle conversion means for refracting or reflecting reflected light from the two-dimensional code irradiated with light from the light emitting unit to the grip unit; And at least two two-dimensional reading means having a structure in which a solid-state imaging device that receives reflected light from the two-dimensional code and outputs an electric signal corresponding to the amount of the reflected light is two-dimensionally arranged. The reflected light incident on each of the two-dimensional reading means from the two-dimensional code on the medium which is close to or close to the reading part via the reflected light angle converting means is converted into the solid state of each of the two-dimensional reading means. Image at the position of the image sensor An optical system mechanism composed of a lens and the like, a semi-transparent mirror that divides light from the optical system mechanism into the two-dimensional reading means, respectively;
Image information conversion means for inputting an electric signal output from the dimension reading means and converting it into one image information, and code information analysis means for analyzing the code information of the two-dimensional code from the image information from the image information conversion means And code information output means for outputting code information obtained by the analysis by the code information analysis means to an external device.
Dimensional code scanner.