JPH06131489A - Portable optical information reader - Google Patents

Abstract

PURPOSE:To provide the optical information reader with good operability which can read both a bar code and an image without spoiling the durability of the bar code. CONSTITUTION:A timing mark sheet 70 is arranged along a two-dimensional image in an information figure 60 and a hand scanner S is slid in the length direction of the timing mark sheet 70 along the timing mark guide 11a to detect and read timing marks by an image sensor 50, not to mention the detection and read of the bar code 61 in the information figure 60 by the image sensor 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical information reading device, and more particularly to a portable optical information reading device suitable for reading optical information such as bar codes and images by sliding.

[0002]

2. Description of the Related Art Conventionally, for example, in a portable bar code reader, the reflected light of a bar code emitted from a light source is imaged on a line sensor such as a CCD through a mirror and a condenser lens to form an image. Some barcodes are detected and read.

[0003]

However, in such a structure, there is a problem that it has only a function of reading a bar code and cannot read an image such as a figure or a character. For this, for example, it is possible to adopt a configuration such as a conventional image scanner.

That is, in this image scanner,
When the operator slides the image scanner in the direction to read an image such as a figure, the roller rotates along the image, and the encoder rotates the slit disk coaxially supported by the roller and the slit circle. The light of the photo interrupter is intermittently passed through each slit of the plate to encode the rotation amount of the roller, that is, the slide amount of the image scanner. In addition, in such a process,
Light reflected from an image such as a figure illuminated by a light source is condensed by a condenser lens to form an image on a line type image sensor, and the image sensor reads the image line by line according to the encoding result. It has become.

However, in such a structure, since the roller plays a role of specifying the reading movement timing in the reading direction with respect to the image, the roller slips on the image when the image scanner slides, or the same image. When contact failure occurs with
The read movement timing cannot be correctly specified. As a result, there arises a problem that the image is difficult to read and cannot be read correctly. Further, in such an image scanner, if the bar code is read, the roller rotates on the bar code, so that it cannot be said that the read operability and the durability of the bar code are sufficient. There are difficulties. From the above, it is difficult for the conventional portable optical information reading device to have both the barcode reading function and the image reading function.

In view of the above, the present invention provides a portable optical information reading device which can read both a bar code and an image without impairing the durability of the bar code. It is what

[0007]

In order to solve the above-mentioned problems, in the present invention, a light source which is arranged in a casing and irradiates an optical information medium in a line form through a reading port of the casing, and the casing. And a line-type image detecting means disposed inside the optical information medium for detecting linearly reflected light from the optical information medium, and the optical information medium is read based on a detection result of the image detecting means. The type optical information reading device is characterized by being configured as follows.

That is, when the optical information medium includes a two-dimensional image, the optical information medium is arranged along the reading direction of the two-dimensional image and each timing mark is provided in the reading direction. A timing mark sheet, the casing is slid in the reading direction while the light source irradiates the two-dimensional image and each of the timing marks through the reading port to detect the image by the image detecting means. Based on the result, the image is read in relation to the reading timing of each timing mark.

[0009]

With the above configuration of the present invention, when the optical information medium includes a two-dimensional image, the timing mark sheet is arranged along the reading direction of the two-dimensional image, and the light source is used. Slides the casing in the reading direction while irradiating the two-dimensional image and each timing mark through the reading port, and reads each timing mark based on the detection result of the image detecting means. Read the image in relation to timing. As a result, not only barcodes, but also two-dimensional images,
With a single optical information reader, the barcode can be read without impairing its durability, which helps improve operability.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings. FIG. 1 shows a portable optical information reading device according to the present invention. This optical information reading device includes a hand scanner S and a signal processing device. And a circuit E. The hand scanner S includes a casing 10, a light source 20, a mirror 30, a condenser lens 40, and a line-type image sensor 50 arranged in the casing 10. The light source 20 has its longitudinal direction (the casing 10 shown in FIG.
In this case, a plurality of light emitting diodes (hereinafter referred to as LEDs) arranged in a line in the width direction in FIG.
From the ED, light is linearly emitted as shown in FIG. 1 through the rectangular reading port 11 formed at the tip of the casing 10 to obtain the information chart 60 and the timing mark sheet 70 placed on the information chart 60. Irradiate. In this case, the information drawing 60 and the timing mark sheet 70 are irradiated with the reading port 11 of the casing 10 closely facing the information drawing 60 and the timing mark sheet 70 in a non-contact state.

On the information map 60, an image composed of a bar code 61 and English characters ABC and COMP and a map 62 is printed together as shown in FIG. In addition, the timing mark sheet 70 is a bar-shaped timing mark 7 on a thin thin plate at regular intervals in the longitudinal direction.
1 is printed, and the reflectance of each timing mark 71 is different from the reflectance of the space portion between these timing marks 71 according to the standard of the contrast ratio of an ordinary barcode. It has become.
Further, in the reading operation, the position of the timing mark sheet 70 placed on the information chart 60 is the timing mark guide 11a provided at the position shown in FIG. 1 on the outer peripheral wall of the reading port 11 of the casing 10 at each timing of the timing mark sheet 70. The hand scanner S is slid along the marks 71 in order. That is,
The timing mark sheet 70 is placed on the information chart 60 so that the direction in which the image is desired to be read matches the longitudinal direction of the timing mark sheet 70.

The mirror 30 reflects the reflected light from the information mark 60 and the timing mark sheet 70 through the reading port 11 of the casing 10 and reflects it toward the condenser lens 40. The condenser lens 40 collects the reflected light from the mirror 30 and makes it incident on the image sensor 50 to form an image of the bar code 61 or the image on the information chart 60 and the timing mark on the timing mark sheet 70 on the image sensor 50. . The image sensor 50 is composed of CCDs or the like arranged in a line parallel to the longitudinal direction of the mirror 31 (width direction of the casing 10).
0 is driven in response to each timing pulse from the timing pulse generation circuit 100 described later, detects the bar code 61 from the condenser lens 40, the image forming the image and the timing mark 71, and generates it as a detection signal. .

The signal processing circuit E includes an amplifier circuit 80, which amplifies the detection signal from the image sensor 50 and generates it as an amplified signal. The AD converter 90 digitally converts the amplified signal from the amplifier circuit 80 and outputs it to the microcomputer 120 as a digital output. The timing generation circuit 100 sequentially generates timing pulses at a predetermined frequency and outputs them to the image sensor 50 and the microcomputer 120.

The PLL circuit 110 has a phase comparison circuit 111 as shown in FIG. 2A, and this phase comparison circuit 111 generates a timing pulse A (see FIG. See B))
And the phase of the divided pulse generated from the frequency divider 114 as will be described later, and the difference between the two phases is generated as a phase difference pulse. The loop filter 112 limits the response characteristic of the system in the PLL circuit 110 based on the phase difference pulse from the phase comparison circuit 111, converts the phase difference pulse into a voltage change, and generates it as a filter voltage. In this case, for example, if the phase difference due to the phase difference pulse is large, the filter voltage becomes high.

The voltage-controlled oscillator 113 oscillates at the free-running frequency and changes the free-running frequency, that is, the oscillation frequency, according to the filter voltage from the loop filter 112, and the voltage-controlled oscillation pulse B (FIG. 2). (See (B)) as a sampling pulse B
0 and output to the frequency divider 114.

Now, assuming that the oscillation frequency of the voltage controlled oscillator 113 is Fo, the pulse frequency of the timing pulse A is Fin, and the frequency division ratio of the frequency divider 114 is N, the following relational expression by the following equation 1 is established. .

[0017]

## EQU1 ## Therefore, if the frequency division ratio is N = 10, the voltage controlled oscillator 1
The oscillation frequency Fo of the voltage controlled oscillation pulse B from 13 is
It is 10 times the pulse frequency Fin of the timing pulse A. This means that the marking density of each timing mark 71 on the timing mark sheet 70 is 10 times the actual density.
It has the same effect as doubling. The frequency divider 114 divides the oscillation frequency of the sampling pulse B from the voltage controlled oscillator 113 by the frequency division ratio N and outputs it as a frequency division pulse to the phase comparison circuit 111. The cycle of the sampling pulse A is slower than the reading speed of the image sensor 50.

The microcomputer 120 executes the computer program in accordance with the flow charts shown in FIGS. 3 and 4 and the A / D converter 90 and the timing generation circuit 10.
0 and the PLL circuit 110 cooperate with each other to perform arithmetic processing necessary for reading the information chart 60 and the timing mark sheet 70. However, the computer program described above is stored in advance in the ROM of the microcomputer 120.

In the present embodiment constructed as above,
With the present invention in operation, for example, the information diagram 60
The timing mark sheet 70 is placed on the information map 60 at the position shown in FIG. In such a state, the operator grips the hand scanner S and reads the reading port 11 of the hand scanner S.
Are maintained so as to closely face the information map 60 and the timing mark sheet 70. In such a case, the timing guide 11a of the reading port 11 is arranged so that the bar code 61 and the English characters of the information chart 60 and each timing mark 71 of the timing mark sheet 70 can be sequentially read.
As shown in FIG. 1, the hand scanner S is maintained along the longitudinal direction of the timing mark sheet 70 so as to be slidable in the arrow direction in FIG.

Further, the microcomputer 120 starts the execution of the computer program in step 200 according to the flowcharts of FIGS.
At 10, each LED of the light source 20 is driven. For this reason,
The light source 20 emits linear light toward the information chart 60 and the timing mark sheet 70 through the reading port 11 as the LEDs are driven. Then, these information
The light reflected by 0 and the timing mark sheet 70 enters the mirror 30 through the reading port 11. Then,
When the mirror 30 reflects the incident light toward the condenser lens 40, the reflected light is condensed by the condenser lens 40 and enters the image sensor 50. As a result, the image such as the bar code or English characters in the information map 60 is formed on the image sensor 50.

At this time, since the image sensor 50 is driven in response to each timing pulse sequentially generated from the timing generation circuit 100, the image sensor 50 is driven.
However, in response to each timing pulse, the imaging light from the condenser lens 40 is detected and a detection signal is generated. In such a process, first, when reading the barcode 61, the reading port 11 of the hand scanner S is set to the barcode 6
1 is maintained in close proximity to 1.

Then, the amplifier circuit 80 amplifies the detection signal from the image sensor 50 as an amplified signal, and the AD converter 90 digitally converts the amplified signal and outputs it as a digital output to the microcomputer 120. Therefore, the microcomputer 120 causes the step 22
The same digital output is input at 0, and the next step 23
At 0, the same bar code 61 based on the digital output.
The widths of the bar portion and the space portion of the bar code are counted, and the bar code information of the bar code 61 is restored and decoded based on the counted data. In such a case, it is unclear whether the digital output from the AD converter 90 is bar code data or image data, but the digital data has a regularity unique to the bar code which is not present in the image data. Therefore, the barcode information is restored based on the combination of the count data. Therefore, assuming that the digital output contains image data, the image data will not be restored. Then, when this decoding process is completed, the microcomputer 120 determines “YES” in step 240, and proceeds to step 24.
At 0a, the decoded data of the bar code 61 is output.

On the other hand, when the decoding process of the bar code 61 is not completed when the computer program proceeds to step 240 as described above, the microcomputer 120 determines "NO" in step 240. At this stage, if the hand scanner S is slid in the direction of the arrow shown in FIG. 1 with the timing guide 11a along the longitudinal direction of the timing mark sheet 70, the value of the detection signal of the image sensor 50 will be It changes with the slide of S. Therefore, in step 240b, the microcomputer 120 outputs the digital output A- with the change in the value of the detection signal.
It is input from the D converter 90.

At this time, the microcomputer 120 causes the timing generation circuit 10 for the image sensor 50 described above.
Since each timing pulse is sequentially input in synchronization with the input of each timing pulse from 0, the detection signal from the image sensor 50, that is, the digital output from the AD converter 90 is the timing of the reading port 11. The position corresponding to the timing mark on the mark sheet 70 is specified. If the timing mark 71 is detected based on the timing mark data being digitally output in step 240b, the microcomputer 120
However, it is determined to be “YES” in step 250, and the timing pulse A is output to the PLL circuit 110 in step 250a.

Then, the phase comparison circuit 111 of the PLL circuit 110 compares the phase of the timing pulse A from the microcomputer 120 with the phase of the frequency-divided pulse generated from the frequency divider 114 at the present stage, and compares both phases. Is generated as a phase difference pulse, the loop filter 112 generates the same phase difference pulse as a filter voltage, and the voltage controlled oscillator 1
13 changes the oscillation frequency according to the filter voltage and generates the voltage controlled oscillation pulse B as the sampling pulse B to generate the microcomputer 120 and the frequency divider 114.
Output to.

Therefore, the microcomputer 120 receives the sampling pulse B from the voltage controlled oscillator 113 in step 250b. This means that the PLL circuit 110 generates the sampling pulse B having a frequency N times the frequency of the timing pulse A.
Therefore, even if the timing mark interval on the timing mark sheet 70, which is a factor that determines the resolution in the sliding direction when the hand scanner S is slid, cannot be narrowed, the pseudo sampling pulse B is generated as described above. The resolution can be substantially improved by equally filling the timing mark intervals on the timing mark sheet 70. As a result, even if the moving speed of the hand scanner S is deviated due to the influence of camera shake or the like in the process of sliding the hand scanner S, the same effect as the moving speed becomes constant between the timing marks is obtained.

In response to the input of the sampling pulse B in step 250b as described above, the microcomputer 120 synchronizes with the input of the sampling pulse B in step 250c and outputs a digital output from the AD converter 90. In step 250d, the image data being digitally output is subjected to various processes such as decoding, shading, and pseudo gradation processing, and in step 250e, the processed data after the same process is performed. Is output. If the processing of the image data is not completed, the microcomputer 120 returns to step 26.
When it is determined to be "NO" at 0, the computer program is returned to step 210. Further, even when the determination in step 250 is “NO”, the microcomputer 12
0 returns the computer program to step 210. If the determination in step 260 is “YES”, the computer program executes step 27.
Go to 0.

As described above, the bar code 61 on the information chart 60 can be detected and read by the image sensor 50, and the timing mark sheet 70 is arranged along the image on the information chart 60. By sliding the hand scanner S in the longitudinal direction of the timing mark sheet 70 along the timing mark guide 11a and detecting the timing mark by the image sensor 50, the durability of the barcode can be improved even for a two-dimensional image. It can be read by a single optical information reader without damaging it, and the operability is significantly improved. In such a case, even if the slide speed of the hand scanner S slightly fluctuates, a good image can be read by the frequency multiplication function of the PLL circuit 110.

In implementing the present invention, instead of the timing mark sheet 70, for example, a timing mark sheet 70A may be adopted as shown in FIG. 5 (A). This timing mark sheet 70A
Has a plurality of bar-shaped timing marks 72 to 72,
As shown in FIG. 5 (A), the timing mark sheet 7
Printing is performed at regular intervals in the scanning direction of 0A in such a manner that the positions are sequentially shifted in the direction perpendicular to the scanning direction (the longitudinal direction of the timing mark sheet 70A). Then, the reading port 11 of the hand scanner S is shown in FIG.
Corresponding to the position indicated by the broken line a in FIG. 5A, the timing pulse A in step 250a is formed as a plurality of timing pulses A1 to A1 as shown in FIG. 5B. When the reading port 11 is made to correspond to the position shown by the broken line b in FIG. 5 (A), the timing pulse A in step 250a is formed as a plurality of timing pulses A2 to A2 as shown in FIG. 5 (C). .

When the reading port 11 is made to correspond to the position shown by the broken line c in FIG. 5 (A), the timing pulse A in step 250a becomes a plurality of timing pulses A3 to A3 as shown in FIG. 5 (D). It is formed. It is known from the waveforms of these respective signals that the signals obtained at the respective slide positions of the hand scanner S are different, and as a result, the slide position of the hand scanner S can be known. Also,
Each timing pulse obtained can be directly used as an address for storing the digital output in the microcomputer 120. Further, instead of the timing mark sheet 70A, as shown in FIG. 6A, a timing mark sheet 70B may be adopted, and in such a case, the timing mark 73 on the timing mark sheet 70B is on the timing mark sheet 70B. Of the respective timing marks 72 to 72.

Further, in implementing the present invention, when a timing mark sheet 70C having a plate thickness is adopted instead of the timing mark sheet 70 as shown in FIG. 6B, the reading port 11 of the hand scanner S is used. The notch 11b may be formed instead of the timing mark guide 11a. In this case, if the width and depth of the notch 11b can escape the width and plate thickness of the timing mark sheet 70C, there is an advantage that the hand scanner S is less likely to be displaced when sliding. If the timing mark sheet 70C is detachably attached to the hand scanner S, it is convenient when there is image information to be read.

In implementing the present invention, the PLL
The circuit 114 may be omitted and implemented.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

2 is a detailed block diagram of the PLL circuit of FIG. 1 and its input / output waveform diagram.

3 is a front part of a flowchart showing the operation of the microcomputer of FIG.

FIG. 4 is a latter part of the flowchart.

5 is a diagram showing a modification of the timing mark sheet of FIG. 1 and a timing pulse waveform diagram thereof.

6A and 6B are diagrams showing other modifications of the timing mark sheet of FIG.

[Explanation of Codes] S ... Hand Scanner, 10 ... Casing, 20 ... Light Source,
50 ... Image sensor, 60 ... Information diagram, 61 ... Bar code, 62 ... Map, 70-70C ... Timing mark sheet, 71, 72, 73 ... Timing mark, 100 ... Timing generating circuit, microcomputer 120.

Claims (1)

[Claims] 1. A light source disposed in a casing for irradiating an optical information medium with light through a reading port of the casing in a line shape, and a light source disposed in the casing for emitting a line shape from the optical information medium. A portable optical information reading device, comprising: a line-type image detecting means for detecting reflected light, and reading the optical information medium based on a detection result of the image detecting means, wherein the optical information medium is two-dimensional. This when the image is included 2
A timing mark sheet which is arranged along the reading direction of the two-dimensional image and is provided with respective timing marks in the same reading direction, wherein the light source irradiates the two-dimensional image and the respective time marks with light through the reading port. Slide the casing in the reading direction while
The portable optical information reading device is characterized in that the image is read in relation to the reading timing of each timing mark based on the detection result of the image detecting means.