JP3225621B2 - Portable optical information reader - Google Patents

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 apparatus for reading optical information of an information medium such as a bar code by scanning with a laser beam from a laser light source.

[0002]

2. Description of the Related Art Conventionally, for example, in a portable laser bar code reader, as shown in Japanese Patent Application Laid-Open No. 56-140467, a laser beam from a laser light source is collimated by a collimator lens and then stepped. The laser beam is reciprocatingly oscillated under a low-frequency drive by a motor. The bar code is scanned with the reflected laser light from the mirror, and the reflected laser light from the bar code is reflected by the mirror to form a condenser lens. There is a type in which a bar code is condensed and then incident on a photodetector, and a barcode is decoded based on a light reception signal from the photodetector, thereby optically reading the barcode.

[0003]

However, in such a configuration, as described above, the reflected laser beam from the mirror scans the bar code while spreading radially with the reciprocating swinging motion of the mirror. Therefore, if there is another barcode within the scanning range of the reflected laser beam, the other barcode may be scanned. For this reason, in some cases, there is a problem that the decoded data of the barcode becomes the decoded data of the barcode not desired to be read. This is particularly noticeable when the barcodes are arranged without gaps. In order to avoid this, the laser barcode reader must be read in close proximity to the barcode, but using it in such a close proximity will make the non-contact portable laser barcode reader easier to use. It was a great loss.

[0004] The present invention, in order to cope with such a fact, the portable optical information reading apparatus, shall be the variable sweep angle of the scanning laser beam that scans the barcode <br/> over de
The purpose is to:

[0005]

According to the first aspect of the present invention, there is provided a laser light source for emitting laser light, a reflecting mirror for reflecting laser light emitted from the laser light source , and Margin and both of these merges
Bars and spaces alternately arranged between
And a barcode having data as
As査run with a reflective laser light, a scanning means and a drive means for swinging driving the reflection mirror when the reflection mirror is reflected by receiving reflected laser light before Symbol bar code or al The reflected laser light is received and the bar
Light receiving means that occurs data over de as Outputs receiving light, Day before Symbol bar code based on the received light output of the light receiving means
In portable optical information reading apparatus and a reading means for taking read the data as information, receiving output of said light receiving means
Binarization means for generating a binary signal by binarizing the force, before
Triggered by the first rising edge of the binary signal
Level, and every subsequent rise of the binary signal
Is retriggered to maintain the high level,
After a predetermined time constant has passed since the last rise of the
Retrieval that generates a bar code identification signal that goes low
Gar-type monostable multivibrator and this
Barco generated from nostable multivibrator
Based on the number of over-de identification signal, said optical scanning means before Kiba
Luba to determine whether to scan over a plurality of keycode
A keycode count determination unit, wherein the first sweep angle setting means for setting a deflection angle range of the reflected laser beam to the first sweep angle, before Symbol barcode number determining means said optical scanning means before Symbol
If it is determined that the scanned bar code plurality above, the first sweep angle to be in the range of scanning the <br/> only a single bar code among the plurality of bar codes the a sweep angle changing means for changing to a narrow second sweep angle than this, the monostable multivibrator
Data is a predetermined time constant, single space of the bar code
Scans across the width of both adjacent bar sections
The scanning time and the mark
Added the time required to scan the entire width of the gin
Time constant setting means for setting so that the sum of time does not exceed
And, pre-Symbol light scanning means, when the scanning, prior Symbol barcode
When the over de count determination unit determined not to be scanned over a plurality of pre-Symbol barcode, oscillating the reflecting mirror by the driving means so as to cause deflection of the reflected laser beam at the first sweep angle driven, also, when the front Symbol barcode number <br/> determination means determines that the scanned over a plurality of pre-Symbol barcode, the reflected laser light as being exposed in the second sweep angle The reflection mirror is swingably driven by the driving means.

[0006]

In [Action and Effect of the Invention] The inventors in this way according to claim 1, when the base Ki barcode reading are not arranged above the plurality includes an optical scanning unit by a bar code number determining unit scans a plurality over the bar code Since it is determined that the bar code has not been scanned, the optical scanning unit scans the bar code in the first deflection angle range using the reflected laser light. On the other hand, Ki base read
When the bar code are arranged above plurality is barcode
Scanning means by de count determination unit is determined that scanning the bar code plurality or, based on the determination result, the range of sweep angle changing unit scans only the single bar code since changing the first sweep angle in the narrow second sweep angle than this to the light scanning means scans only the single bar code at a second sweep angle with the reflected laser beam. Therefore, a portable optical reader and a scanning device should be used.
Barcode in a state in which the interval between the gas bar code is away
Even if something like to scan over a plurality of de, single
Since the deflection angle of the reflected laser beam so as to scan only the bar code which is automatically adjusted to a narrower second sweep angle than the first sweep angle, maintaining the portable optical reading device to the current position Each of the barcodes can be read separately while keeping the same . Here, as described above,
Cable multivibrator is the time constant setting means
The specified time constant is set in one space of the barcode.
Scanning across the width of both adjacent bar parts
And the margin time
Sum of the time required to scan the entire width direction of the minute
Is not exceeded. Therefore, the light scanning means
Monostable multivibration during one scan
A single barcode identification signal by retrigger
Occurrence is identified only by a single barcode
You. As a result, separate reading of each barcode described above
Can be done correctly.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a portable optical information reading apparatus according to the present invention.
It is constituted by a hand scanner S and an electric control circuit E for the hand scanner S. The hand scanner S is, as shown in FIG.
0a, a semiconductor laser diode 30 (corresponding to a laser light source) ,
0, light scanning mechanism 50 (corresponding to light scanning means) , light receiving side condenser lens 60 and photodetector 70 (corresponding to light receiving means), and power supply circuit 8 housed in hand portion 10b of casing 10
0, and the semiconductor laser diode 30 emits a laser beam toward the collimator lens 40 according to the operating current. The collimator lens 40 collimates the laser light emitted from the semiconductor laser diode 30 and transmits the collimated laser light toward the optical scanning mechanism 50.

The optical scanning mechanism 50 includes a step motor 51
And a flat mirror 52, and the step motor 51 is mounted on the electronic board 20 behind the collimator lens 40. The mirror 52 is coaxially supported by an output shaft extending vertically upward from the step motor 51 with respect to the electronic board 20.
Is driven at a low frequency by a step motor 51 as described later, and makes a reciprocating swinging motion in the direction of the arrow shown in FIG. The mirror 52 receives and reflects the laser light from the collimator lens 40 under the reciprocating swinging motion, and reflects the reflected laser light on the casing 1.
The bar code 90 is made to pass through a window 11 provided on the head 10a of the "0" and is scanned. The mirror 52 receives the reflected laser light (hereinafter, referred to as a barcode laser light) from the barcode 90 through the window 11 and reflects it toward the condenser lens 60. The condensing lens 60 receives and condenses the barcode laser light reflected from the mirror 52 and makes it incident on the photodetector 70. The photodetector 70 is formed of, for example, a phototransistor. The photodetector 70 receives the amount of light of the converging barcode laser beam in response to the converging barcode laser beam from the converging lens 60. Generated as a detection signal.

Next, the circuit configuration of the electric control circuit E will be described with reference to FIG.
The right part of the hand section 10b of the hand scanner S (see FIG. 2)
Trigger switch 100
Is operated at the start of scanning by the mirror 52 to generate a mirror scanning signal, and a microcomputer 160 to be described later
Output to Laser diode drive circuit 110 (hereinafter, referred to as
The LD driving circuit 110 supplies an operating current to the semiconductor laser diode 30 under the control of the microcomputer 160 so that the semiconductor laser diode 30 emits laser light in response to power supply from the power supply circuit 80. Apply and drive this. Motor drive circuit 120
Is controlled by the microcomputer 160,
The stepping motor 51 is driven at low frequency forward and reverse at about 50 (Hz) in response to power supply from the power supply circuit 80. Amplifier circuit 1
Reference numeral 30 amplifies the received light detection signal from the photodetector 70 to generate an amplified signal. The binarizing circuit 140 binarizes the amplified signal from the amplifying circuit 130 to generate a binarized signal and outputs it to the microcomputer 160.

[0010] Bar code identification circuit 150, the re-trigger type monostable multivibrator 150a (hereinafter, referred to as R-M M150a) and is constituted by a binary counter 150b in 4 bits. RM M1
Reference numeral 50a denotes a trigger terminal, which receives a binarized signal as a trigger signal from the binarization circuit 140, is triggered by the rising edge of the trigger signal, and is at a high level for a predetermined time constant τ. the occurred, then
The bar code identification signal is continuously generated by being repeatedly retriggered every time the trigger signal from the binarization circuit 140 rises. In such a case, the above-described predetermined time constant τ is defined by the resistor R and the capacitor C of the R-MM 150a. However, in the present embodiment, R-M M1
50a, Texas Instruments 7
A 4LS123 type monostable multivibrator is employed.

The binary counter 150b is reset at its inverted reset terminal RES every time the microcomputer 160 performs a reset control, and the clock terminal CK
, The bar code identification signal is input from the R-MM 150a, the high level state of the bar code identification signal is counted, and the bar code identification signal is counted from the output terminal Qb (corresponding to the output terminal of the second bit from the least significant bit LSB). An output signal is generated and output to the microcomputer 160. In such cases,
The reset control by the microcomputer 160 is performed every time a mirror scanning signal is generated from the trigger switch 100 as described later. However, in this embodiment,
As the binary counter 150b, a 74LS393 type binary counter manufactured by Texas Instruments of the United States is used.

The grounds for configuring the barcode identification circuit 150 as described above will be described. The bar code identification circuit 150 causes the microcomputer 160 to change the swing angle range of the mirror 52 (that is, the swing angle range of the reflected laser light from the mirror 52) according to the number of bar codes scanned by the laser light, as described later. In making the determination, it is employed to identify the likeness of a bar code from data obtained during scanning. The characteristics of barcode data are used to identify the likeness of barcodes. As a feature of the barcode data, for example, a pattern having a large contrast ratio is continuous to some extent because data of a black bar portion and data of a white space portion alternately exist. Since both ends of the barcode have a margin portion, the data of the margin portion exists. In such a case, the size of the margin portion is determined by the bar code standard.

Therefore, in the present embodiment, the barcode identification circuit 150 is configured as described above by utilizing such characteristics of the barcode. In such a case, the aforementioned R-MM150
The predetermined time constant τ at a is determined as follows. That is, the bar code includes the time required for scanning over the entire width direction of both bar portions adjacent to each other via one space portion, and the scanning time includes the time required for scanning the entire bar code margin portion in the width direction. The predetermined time constant τ is set so as not to exceed the added time sum. Thereby, the generation of a single barcode identification signal due to the retrigger from the R-MM 150a during one scan is
Identified only by a single barcode. Therefore, if a plurality of barcode identification signals are generated from the R-MM 150a during one scan, a plurality of barcodes have been scanned. As a result, when the count signal of the binary counter 150b is represented by 4 bits, the lowest LSB is 2 bits.
When the bit is “1”, it means that the binary counter 150b has counted two or more barcode identification signals from the R-MM 150a. If the number of barcode identification signals from the R-MM 150a counted by the binary counter 150b is one, the value of the count signal from the output terminal Qb of the binary counter 150b is “0”. Therefore, it can be understood that the range of the deflection angle of the reflected laser light from the mirror 52 can be determined according to the number of barcodes by utilizing the counting result.

The microcomputer 160 executes the computer program according to the flowcharts shown in FIGS.
And in cooperation with the barcode identification circuit 150,
During this execution, the drive control of the LD drive circuit 110 and the motor drive circuit 110 is performed, and arithmetic processing necessary for outputting data is performed. However, the computer program is stored in the ROM of the microcomputer 160 in advance.

In this embodiment configured as described above,
If the device of the present invention is put into an operating state in response to the start-up of the power supply circuit 80 by turning on the power, the microcomputer 160
Starts the computer program in step 200 according to the flowcharts of FIGS.
At 10, initialization processing is performed, and at the next step 220,
The deflection angle range Φ of the mirror 52 is set to the first deflection angle range Φ1 representing a large deflection angle range. However, this first swing angle range Φ1 corresponds to the range of the swing angle ± θ1 of the mirror 52 and is stored in the ROM of the microcomputer 160 in advance.

The hand unit 1 of the hand scanner S
When the trigger switch 100 generates a mirror scanning signal (see symbol A in FIG. 5) with the window 11 of the head 10a facing the barcode 90 while gripping 0b, the microcomputer 160 executes At 230, "YE
S ”, a reset signal required to reset the binary counter 150b is generated in step 240, and an LD drive signal required to generate laser light from the semiconductor laser diode 30 is generated in step 250. At the same time, a first motor drive signal necessary for rotating the stepping motor 51 forward and backward is generated in a rotation angle range corresponding to the first deflection angle range Φ1.

Then, the binary counter 150b is reset by a reset signal from the microcomputer 160. The LD drive circuit 110 is connected to the power supply circuit 8.
The semiconductor laser diode 30 responds to the LD drive signal from the microcomputer 160 under the power supply from 0.
The operating current flows into the device. Therefore, the semiconductor laser diode 30 emits the laser light toward the collimator lens 40. Then, the laser beam is collimated by the collimating lens 40 and the mirror 5 of the optical scanning mechanism 50
2 is incident. Further, the motor drive circuit 120 is controlled by the microcomputer 16 under the power supply from the power supply circuit 80.
In response to the first motor drive signal from 0, the low-frequency forward / reverse drive of the step motor 51 is started. Therefore, the mirror 52 starts a single reciprocating swing motion in the first swing angle range Φ1 (see FIG. 6) in response to the low-frequency normal / reverse drive of the step motor 51.

The mirror 52 receives the laser beam from the collimator lens 40 and reflects it under a single reciprocating swinging motion over the first swing angle range Φ1. Bar code 9 through 10 windows 11
The laser beam is made to scan at 0 (see FIG. 6). In this one scanning process, when the mirror 52 receives the barcode laser beam reflected from the barcode 90 through the window 11 and reflects it toward the condenser lens 60, the barcode laser beam reflected from the mirror 52 is reflected by the condenser lens 60. And is incident on the photodetector 70.

Then, the photodetector 70 responds to the converging barcode laser beam from the converging lens 60 and generates the amount of received light of the converging barcode laser beam as a light receiving detection signal. In such a case, in the received light detection signal, the difference in the reflectance of the bar code 90 with respect to the laser light between the bar portion and the space portion appears as the level of the received light detection signal. When the light detection signal is generated from the photodetector 70 as described above, the amplification circuit 130 amplifies the light reception detection signal to generate an amplified signal, and the binarization circuit 140 converts the amplified signal into a binary signal (FIG. 5, and outputs it to the R-MM 150a and the microcomputer 160.

Next, the R-MM 150a is triggered by the first rising edge of the binarized signal from the binarizing circuit 140, and generates a bar code identification signal (see reference numeral C1 in FIG. 5). And this R-MM 150a is 2
Each time the rising edge of the binarized signal from the digitizing circuit 140 rises after the first rising, it is retriggered to maintain the generation of the bar code identification signal. Since the bar code identification signal is only the bar code 90, it falls when a predetermined time constant τ elapses after the last rise of the binary signal from the binary circuit 140 (see reference numeral C1 in FIG. 5). When the binary counter 150b counts the bar code identification signal from the R-MM 150a in the reset state as described above, the number of the bar code identification signal is one. Therefore, the output terminal Qb of the binary counter 150b is counted. The value of the count signal output from is "0" (see D1 in FIG. 5).

The counting signal is transmitted to the microcomputer 1
Is input at step 260 to 60, the microcomputer 160, to step 270 (medium speed decision means
) , The value of the counting signal is “0”,
It is determined as “NO”, and in step 280, step 25
As in the case of 0, the LD drive signal and the first motor drive signal are generated again. Therefore, similarly to the above, the mirror 52 receives the laser beam from the collimator lens 40 and reflects it through the window 11 of the casing 10 under a single reciprocating swinging motion over the first swing angle range Φ1. Bar code 9
This is made to scan at 0. In this one scanning process, when the mirror 52 receives the barcode laser beam reflected from the barcode 90 through the window 11 and reflects it toward the condenser lens 60, the barcode laser beam reflected from the mirror 52 is reflected by the condenser lens 60. Condensed by the photodetector 7
Incident at 0. Then, the photodetector 70 generates the amount of received light of the converged barcode laser light as a light reception detection signal in response to the converged barcode laser light from the condensing lens 60, and the amplification circuit 130 The signal is amplified to generate an amplified signal. The binarization circuit 140 converts the amplified signal into a binarized signal and outputs it to the microcomputer 160.

Next, the microcomputer 160
At step 310, the binarization signal from the binarization circuit 140 is read as binarized data, and based on the binarized data, the width of each bar and the width of each space of the barcode 90 are digitized. A normal barcode decoding process such as decoding and restoring the barcode information of the barcode 90 from the combination of each of the digitized data is performed, and the result of the barcode decoding process is output as decoded data in step 320. .

Instead of the barcode 90, the barcodes 90a and 90b are scanned one round trip by the laser beam under the above-described arithmetic processing in step 250, as shown in FIG. In such a case, the photodetector 70
In response to each bar code laser beam from the mirror 52 corresponding to each bar code 90a, 90b, the light reception amount of each bar code laser beam is sequentially generated as a light reception detection signal. As described above, when each light reception detection signal is sequentially generated from the photodetector 70, the amplifier circuit 130 amplifies each light reception detection signal and sequentially generates an amplified signal, and the binarization circuit 140 sequentially converts each amplified signal. The signal is converted into a binary signal (refer to symbols B2 and B3 in FIG. 5), and the R-MM 150a and the microcomputer 1
Output to 60.

Next, the R-MM 150a is triggered by the first rising edge of the first binarized signal (see B2 in FIG. 5) from the binarizing circuit 140, and the first bar code identification signal (see FIG. 5). 5 to generate a reference C2). The R-MM 150a is a binarizing circuit 14
It is retriggered at every rising edge after the first rising edge of the first binarized signal from 0 to maintain the generation of the bar code identification signal. This bar code identification signal falls when a predetermined time constant τ elapses after the last rise of the first binarized signal from the binarization circuit 140 (reference numeral C2 in FIG. 5).
reference).

Thereafter, the R-MM 150a is triggered by the first rising edge of the second binarized signal (see B3 in FIG. 5) from the binarizing circuit 140, and the second bar code is output. An identification signal (see C3 in FIG. 5) is generated. The R-MM 150a is a binarizing circuit 14
It is retriggered at every rising edge after the first rising edge of the second binarized signal from 0 to maintain the generation of the second bar code identification signal. The second barcode identification signal falls when a predetermined time constant τ elapses after the last rise of the second binarized signal from the binarization circuit 140 (see reference numeral C3 in FIG. 5). When the binary counter 150b sequentially counts both barcode identification signals from the R-MM 150a in the reset state, the output terminal Qb of the binary counter 150b
The value of the count signal (see D2 in FIG. 5) output from is "1".

The counting signal is transmitted to the microcomputer 1
When the count is input to step 60 at step 260, the microcomputer 160 determines at step 270 that the number of barcodes is 2 because the value of the count signal is “1”. "YES", and step 290 (contract
In the shake angle range changing means described in claim 1 , the shake angle range Φ of the mirror 52 is set to the second shake angle range Φ2 representing a small shake angle range. However, this second swing angle range Φ2 corresponds to the range of the swing angle ± θ2 (θ2 <θ1) of the mirror 52 and is stored in the ROM of the microcomputer 160 in advance.

Next, the microcomputer 160
In step 300, an LD drive signal is generated, and a second motor drive signal required to rotate the step motor 51 in the normal and reverse directions within a rotation angle range corresponding to the second deflection angle range Φ2 is generated. Then, similarly to the above, the LD driving circuit 1
The laser light emitted from the semiconductor laser diode 30 by the collimator 10 is collimated by the collimator lens 40 and enters the mirror 52. Also, the motor drive circuit 120
Starts the low frequency forward / reverse drive of the step motor 51 in response to the second motor drive signal from the microcomputer 160. For this reason, the mirror 52 moves the second swing angle range Φ2 in accordance with the low-frequency forward / reverse drive of the step motor 51.
Starts one reciprocating rocking motion with.

The mirror 52 receives and reflects the laser light from the collimator lens 40 under one reciprocating swinging motion over the second deflection angle range Φ2, and reflects the reflected laser light on the casing. Bar code 9 through 10 windows 11
The light is made incident on 0a or 90b and scanned. At this time, the window 11 of the hand scanner S is turned to the barcode 90a or 90b at the same position. In this one scanning process, when the mirror 52 receives the barcode laser beam reflected from the barcode 90a or 90b through the window 11 and reflects it toward the condenser lens 60, the barcode laser beam reflected from the mirror 52 is collected. The light is condensed by the lens 60 and enters the photodetector 70. Then, the photodetector 70 generates the amount of received light of the converged barcode laser light as a light reception detection signal in response to the converged barcode laser light from the condensing lens 60, and the amplification circuit 130 The signal is amplified to generate an amplified signal. The binarization circuit 140 converts the amplified signal into a binarized signal and outputs it to the microcomputer 160. In such a case, as described above, the mirror 5
2 is smaller than Φ1, Φ2 is smaller than Φ1, and the reflected laser beam from the mirror 52 is a bar code 90a.
Or, scan only 90b. Therefore, the binarization circuit 140
Is specified by only the barcode 90a or 90b.

Next, the microcomputer 160
In step 310, the binarization signal from the binarization circuit 140 is read as binarized data, and the width of each bar and the width of each space of the bar code 90a or 90b are digitized based on the binarized data. In addition, a normal barcode decoding process such as decoding and restoring the barcode information of the barcode 90a or 90b from the combination of each of the digitized data is performed, and the result of the barcode decoding process is decoded in step 320. Output as data.

As described above, the first deflection angle range Φ1
As a result of one scan of the bar code by the reflected laser light from the mirror 52 over the entire range, if the number of bar codes related to the scanning is single, the bar by the reflected laser light from the mirror 52 over the first deflection angle range Φ1 One scan of the code is repeated as it is, and barcode data obtained by this scan is decoded and output. On the other hand, when the number of barcodes related to the above-described scan is two, the swing angle range of the mirror 52 is changed. The second deflection angle range Φ2 is narrower than the first deflection angle range Φ1, and only a single bar code is scanned by the laser beam reflected from the mirror 52.

In other words, the number of bar codes involved in scanning is automatically detected, and when the number of detected bar codes is two or more, the first deflection angle when the number of detected bar codes is one is detected. As compared with the range Φ1, the deflection angle range Φ of the reflected laser light from the mirror 52 is automatically narrowed to the second deflection angle range Φ2, and only a single bar code is reflected by the reflected laser light from the mirror 52. Therefore, even when the distance between the window 11 of the hand scanner S and the barcode to be scanned is large, it is always possible to easily adjust the scanning sight to only a single barcode and read it. it can. as a result,
Even more the number of bar codes to be read can take read each bar code separately from each other. This place
In this case, as described above, the R-MM 150a
The predetermined time constant τ defined by the capacitor C is
The width of both bar parts adjacent via one space part of the code
Includes the time required to scan across the
Required to scan the entire width of the margin part at inspection time
It does not exceed the sum of time plus time. Follow
Retrigger from the R-MM 150a during one scan
The generation of a single bar code identification signal by the
-Identified only by code. As a result,
Separate reading of each bar code
You.

In this embodiment, the swing angle range Φ of the mirror 52 is set to the first and second swing angle ranges Φ1 and Φ2.
However, instead of this, the swing angle range Φ of the mirror 52 may be switched in multiple steps or continuously.

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an electric control circuit according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a schematic configuration of a hand scanner of the embodiment.

FIG. 3 is a first part of a flowchart showing the operation of the microcomputer of FIG. 1;

FIG. 4 is a latter part of the flowchart.

FIG. 5 is a time chart showing an output waveform of each main element in the electric control circuit.

FIG. 6 is a diagram illustrating a scanning state of a laser beam of the hand scanner in the embodiment.

[Explanation of symbols]

S: optical information reading device, 30: semiconductor laser diode, 50: optical scanning mechanism, 60: condenser lens, 70: photodetector, 90, 90a, 90b: bar code, 100:
Trigger switch, 140: binarization circuit, 150: barcode identification circuit, 160: microcomputer.

Claims (1)

(57) [Claims] 1. A laser light source for emitting laser light, a reflection mirror for reflecting laser light emitted from the laser light source, and an intersection between both margin portions.
The bar part and space part which are arranged mutually are data.
Bar code with the reflected laser light of the reflecting mirror
As査run with a scanning means and a drive means for swinging driving the reflection mirror, the reflected laser beam when the reflecting mirror is reflected by receiving reflected laser light before Symbol bar code or al Receiving the
Light receiving means that occurs data keycode as Outputs receiving light, de prior Symbol bar code based on the received light output of the light receiving means
In portable optical information reading apparatus and a reading means for taking read the chromatography data as information, generating a binary signal by binarizing the light receiving output of said light receiving means
And a trigger which is triggered by the first rising edge of the binary signal.
Level, and the subsequent rise of the binary signal
Each time it is retriggered to maintain the high level,
After a predetermined time constant has passed since the last rise of the
To generate a bar code identification signal
Rigger type monostable multivibrator and generated from this monostable multivibrator
Based on the number of barcodes identification signal, said optical scanning means comprises a bar code number determining means you determine <br/> whether scanned over a plurality of <br/> before Symbol bar code, said reflector a first sweep angle setting means for setting a sweep angle of the laser beam to the first deflection angle range, the optical scanning unit before Symbol bar code number determining means before Symbol bar
If it is determined that more than one code is scanned,
And a single sweep angle changing means for changing the first sweep angle to be in the range of scanning only the bar code to the narrower second sweep angle than this one of the plurality of bar codes The monostable multivibrator is provided with the predetermined
The time constant is adjacent through one space of the barcode
When scanning across the entire width of both bars
And the width of the margin portion during this scanning time.
Do exceeds the time sum plus the time required for you scan direction across
Has a constant setting means when setting the odd, before Symbol light scanning means, when the scanning, prior Symbol barcode
When the number determination means determines not to be scanned over a plurality of pre-Symbol barcode, the reflecting mirror is swung by the drive means the reflected laser beam so as cause deflection in the first sweep angle Further, when the front Symbol barcode number determination means determines that the scanned over a plurality of pre-Symbol bar code, said by the driving means so as to cause deflection of the reflected laser beam at the second sweep angle A portable optical information reading device characterized by oscillatingly driving a reflection mirror.