JPS61193273A - Bar code reader - Google Patents

Bar code reader

Info

Publication number
JPS61193273A
JPS61193273A JP60033304A JP3330485A JPS61193273A JP S61193273 A JPS61193273 A JP S61193273A JP 60033304 A JP60033304 A JP 60033304A JP 3330485 A JP3330485 A JP 3330485A JP S61193273 A JPS61193273 A JP S61193273A
Authority
JP
Japan
Prior art keywords
circuit
signal
image sensor
signal level
waveform shaping
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP60033304A
Other languages
Japanese (ja)
Inventor
Keiichi Kobayashi
圭一 小林
Seiichiro Tamai
誠一郎 玉井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP60033304A priority Critical patent/JPS61193273A/en
Publication of JPS61193273A publication Critical patent/JPS61193273A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To enable stable bar code interpreting processing by detecting the output signal level of the image sensor and in case the signal level is outside the prescribed set range, effect adjustment of the amplification factor of the image sensor output signal. CONSTITUTION:The output of the image sensor 1, after amplified by the initial stage amplification circuit 2, is input into the variable gain amplification circuit 3, thence converted from dispersing signal to continuous signal by the waveform shaping circuit 4. The scanning part 1 of the converted signal is averaged by the hold circuit 7 and the held signal is converted to digital signal by the light receiving signal level judgment circuit 8, and input into the microprocessor 9 via the input port 9a. At the microprocessor 9, based on the optical signal level, waveform shaping-binarizing is always carried out on a constant signal level with no effect of the printing condition of the bar code. Thereby, accurate bar code interpreting process is possible.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、バーコード上をイメージセンサを用いて光学
的に走査し、バーコードを読み取るバーコード読取装置
に関するものである。
DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a barcode reading device that optically scans a barcode using an image sensor to read the barcode.

従来の技術 従来、バーコード読取装置は、バーコード上に光を照射
し、その反射光を読取センサ上のレンズを用いて読取セ
ンサ上に結像させ、電気信号に変換してバーコードの解
読処理を行っていた。
Conventional technology Conventionally, barcode reading devices irradiate light onto a barcode, use a lens on the reading sensor to form an image of the reflected light on the reading sensor, and convert it into an electrical signal to decode the barcode. It was being processed.

発明が解決しようとする問題点 しかし今日バーコードは、各種の品物に印刷され、その
印刷媒体も色・材質等さまざまなものになっている。し
かるにバーコードの色も各種あり、その反射率も一定で
はない。よって反射率の低いバーコードを読み取る場合
は読取センサの出力は小さく、反射率の高いバーコード
を読み取る場合は読取センサの出力は大きくなる。この
ように反射率の異なるバーコードを読み取る毎に読取セ
ンサの出力は変動してしまう。したがって読取センサ出
力の信号処理、波形整形等が困難となり、正確なバーコ
ード読み取りが行えないという問題が生じる。
Problems to be Solved by the Invention Today, however, barcodes are printed on a variety of items, and the printing media are also available in a variety of colors and materials. However, barcodes come in a variety of colors, and their reflectance is not constant. Therefore, when reading a barcode with low reflectance, the output of the reading sensor is small, and when reading a barcode with high reflectance, the output of the reading sensor becomes large. In this way, the output of the reading sensor varies each time a barcode with a different reflectance is read. Therefore, it becomes difficult to perform signal processing, waveform shaping, etc. of the output of the reading sensor, resulting in the problem that accurate barcode reading cannot be performed.

問題点を解決するための手段 上記問題点を解決するため、本発明のバーコード読取装
置は、少なくとも2種類以上の幅をもつバーを順次配列
したバー記号からなるバーコード上を光学的に走査して
複数ビットの映−信号に変換するイメージセンサと、こ
のイメージセンサの映像信号を増幅しかつ外部指令信号
により増幅率を可変される可変利得増幅回路と、この可
変利得増幅回路の離散的映像信号を連続信号に変換する
波形整形回路と、この波形整形回路の連続信号の1走査
分を平均し保持するホールド回路と、前記ホールド回路
の出力信号が所定の範囲内であるか否かの判定を行なう
受光信号レベル判定回路と、この受光信号レベル判定回
路の判定結果に基づき前記可変利得増幅回路の増幅率を
指令して増幅率の設定を行い、設定後、前記ホールド回
路の出力信号が所定の範囲内にある場合に、前記バーコ
ードデータの解読処理を行う判定処理手段とを備えた構
成と□したものである。
Means for Solving the Problems In order to solve the above problems, the barcode reading device of the present invention optically scans a barcode consisting of a bar symbol in which bars having at least two different widths are sequentially arranged. an image sensor that converts the video signal into a multi-bit video signal, a variable gain amplifier circuit that amplifies the video signal of the image sensor and whose amplification factor is varied by an external command signal, and a discrete video signal of the variable gain amplifier circuit. A waveform shaping circuit that converts a signal into a continuous signal, a hold circuit that averages and holds one scan of the continuous signal of this waveform shaping circuit, and a determination whether the output signal of the hold circuit is within a predetermined range. The amplification factor is set by commanding the amplification factor of the variable gain amplifier circuit based on the judgment result of the received light signal level judgment circuit, and after setting, the output signal of the hold circuit is set to a predetermined value. and a determination processing means for decoding the barcode data when the barcode data is within the range of .

作用 上記構成によれば、バーコードデータをイメージセンサ
を用いて電気信号に変換し、バーコードの解読処理を行
うバーコード読取装置において、イメージセンサの出力
信号レベルを検知し、信号レベルが所定の設定筒器外で
あれば、イメージセンサ出力信号の増幅率を調整し、イ
メージセンサの出力信号が所定の範囲内である場合に、
バーコードの解読処理を行うようにしたので、反射率の
異なる種々のバーコードに対しても、イメージセンサ出
力は常に一定の振幅の信号レベルとなり、波形整形・2
値化等の信号処理が正確に行え、安定したバーコード解
読処理が可能となる。
According to the above configuration, in a barcode reading device that converts barcode data into an electrical signal using an image sensor and performs barcode decoding processing, the output signal level of the image sensor is detected and the signal level is determined to be a predetermined level. If it is outside the setting cylinder, adjust the amplification factor of the image sensor output signal, and if the image sensor output signal is within a predetermined range,
Since barcode decoding processing is performed, the image sensor output always has a constant amplitude signal level even for various barcodes with different reflectances, and waveform shaping and
Signal processing such as value conversion can be performed accurately, and stable barcode decoding processing is possible.

実施例 以下、本発明の一実施例を第1図〜第4図に基づいて説
明する。
EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

第1図は本発明の一実施例におけるバーコード読取装置
の回路ブロック図、第2図は第1図に示す回路ブロック
の各部信号波形図で、1はイメージセンサ、2はイメー
ジセンサ1の出力を増幅する初段増幅回路、3は可変利
得増幅回路、4は波形整形回路、5はローパスフィルタ
、6は2値化回路、7は1走査間のイメージセンサ出力
を平均し保持するホールド回路、8は受光信号レベル判
定回路、9はマイクロプロセッサ、1Gはタイミング発
生回路である。
FIG. 1 is a circuit block diagram of a barcode reading device according to an embodiment of the present invention, and FIG. 2 is a signal waveform diagram of each part of the circuit block shown in FIG. 1, where 1 is an image sensor and 2 is an output of image sensor 1. 3 is a variable gain amplifier circuit, 4 is a waveform shaping circuit, 5 is a low-pass filter, 6 is a binarization circuit, 7 is a hold circuit that averages and holds the image sensor output during one scan, 8 9 is a light receiving signal level determination circuit, 9 is a microprocessor, and 1G is a timing generation circuit.

第3図は第1図に示す回路ブロックの具体回路図で、1
1〜14は演算増幅器、15〜17はアナログス゛  
イッチ、D1〜D3はダイオード、R1−R15は抵抗
、C1〜C6はコンデンサである。イメージセンサ1は
1次元QCQ (charge  coupledde
vice)から、可変利得増幅回路3は演算増幅器11
とアナログスイッチ17とから、1走査のホールド回路
7は演算増幅器14とアナログスイッチ15゜16とコ
ンデンサOs 、 C+sとから、受光信号レベル判定
回路8はA/Dコンバータからそれぞれ構成されている
Figure 3 is a specific circuit diagram of the circuit block shown in Figure 1.
1 to 14 are operational amplifiers, and 15 to 17 are analog switches.
D1 to D3 are diodes, R1 to R15 are resistors, and C1 to C6 are capacitors. The image sensor 1 is one-dimensional QCQ (charge coupled
vice), the variable gain amplifier circuit 3 is an operational amplifier 11.
and an analog switch 17, a one-scan hold circuit 7 is composed of an operational amplifier 14, an analog switch 15, 16, and capacitors Os and C+s, and a received light signal level determination circuit 8 is composed of an A/D converter.

第4図はマイクロプロセッサ9の動作を示すフローチャ
ートである。
FIG. 4 is a flowchart showing the operation of the microprocessor 9.

次に動作を説明する。イメージセンサ1の出力は、初段
増幅回路2により増幅された後、可変利得増幅回路3へ
入力される。可変利得増幅回路3の出力は、波形整形回
路、4により第2図aに示す離散的信号から第2図すに
示す連続信号に変換される。変換された信号は、ホール
ド回路7により1走査分を平均され、そ、の結果がホー
ルドされる。
Next, the operation will be explained. The output of the image sensor 1 is amplified by the first stage amplifier circuit 2 and then input to the variable gain amplifier circuit 3. The output of the variable gain amplifier circuit 3 is converted by a waveform shaping circuit 4 from a discrete signal shown in FIG. 2a to a continuous signal shown in FIG. The converted signal is averaged for one scan by a hold circuit 7, and the result is held.

ホールドされた信号は、受光信号レベル判定回路8によ
りデジタル信号に変換され、入力ボート9aよりマイク
ロプロセッサ9に入力される。マイクロプロセッサ9で
は、受光信号レベルに基づき、受光信号レベルが所定の
範囲内であれば、初段増幅回路2及び可変利得増幅回路
3で増幅されたイメージセンサ1の出力信号を、波形整
形回路4で連続した映像信号”に波形整形し、ローパス
フィルタ5でバコードの映像信号周波数より高いノイズ
成分を削除し、2値化回路6で、第2図Cに示すように
、バーが有る場合は「1」レベル、バ−が無い場合はr
OJレベルの2値化信号に変換した後に、入力ボート9
bよりマイクロプロセッサ9に取り込み、バーコードの
解読処理を行う。
The held signal is converted into a digital signal by the received light signal level determination circuit 8, and is input to the microprocessor 9 via the input port 9a. Based on the received light signal level, the microprocessor 9 converts the output signal of the image sensor 1 amplified by the first stage amplifier circuit 2 and the variable gain amplifier circuit 3 into the waveform shaping circuit 4 if the received light signal level is within a predetermined range. The waveform is shaped into a continuous video signal, the noise components higher than the barcode video signal frequency are removed by the low-pass filter 5, and the binarization circuit 6 converts the bar code to 1 if there is a bar, as shown in FIG. 2C. ” level, r if there is no bar
After converting to OJ level binary signal, input port 9
The data is read into the microprocessor 9 from b, and the bar code is decoded.

また受光信号レベル判定回路8の出力が所定の範囲外で
あれば、出力ボート9Cより可変利得増幅回路3へ増幅
率の指令を出力し、可変利得増幅回路3の増幅率を変化
させて再び受光信号レベルの判定を行い、所定の受光信
号レベルの範囲に入るまで上記の操作を繰り返す。
If the output of the received light signal level determination circuit 8 is outside the predetermined range, the output port 9C outputs an amplification factor command to the variable gain amplifier circuit 3, changes the amplification factor of the variable gain amplifier circuit 3, and receives light again. The signal level is determined and the above operations are repeated until the received light signal level falls within a predetermined range.

以上の操作により、イメージセンサ1の出力信号は、常
に一定の信号レベルにて波形整形・2111化が行われ
、バーコードの印刷状況の影響は受けない。したがって
、上記バーコード読取装置では、正確なバーコード解読
処理が可能となる。なおタイミング発生回路10は、マ
イクロプロセッサ9の出力ボート9dからの出力により
、イメージセンサ1の走査パルス及び1走査分のホール
ドタイミングパルスを発生する。
Through the above operations, the output signal of the image sensor 1 is waveform-shaped and converted into 2111 signals at a constant signal level, and is not affected by the printing status of the barcode. Therefore, the barcode reading device described above enables accurate barcode decoding processing. Note that the timing generation circuit 10 generates a scan pulse for the image sensor 1 and a hold timing pulse for one scan based on the output from the output port 9d of the microprocessor 9.

発明の効果 以上述べたごとく本発明によれば、バーコードの印刷状
況により反射率の異なったバーコードを読み取った場合
においても、常に安定したバーコード読み取りを行なう
ことができる。
Effects of the Invention As described above, according to the present invention, even when barcodes with different reflectances are read depending on the printing conditions of the barcode, stable barcode reading can be performed at all times.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は本発明の一実施例におけるバーコード読取装置
の回路ブロック図、第2図は第1図に示す回路ブロック
の各部信号波形図、第3図は本発明の一実施例における
バーコード読取装置の具体的回路図、第4図は同バーコ
ード読取装置におけるマイクロプロセッサの動作を示す
フローチャートである。 1・・・イメージセンサ、3・・・可変利得増幅回路、
4・・・波形整形回路、7・・・ホールド回路、8・・
・A/Dコンバータ、9・・・マイクロブセッサ代理人
   森  本  義  弘 第2図 14閑 第4図
FIG. 1 is a circuit block diagram of a barcode reader according to an embodiment of the present invention, FIG. 2 is a signal waveform diagram of each part of the circuit block shown in FIG. 1, and FIG. 3 is a barcode reader according to an embodiment of the present invention. FIG. 4, which is a specific circuit diagram of the reading device, is a flowchart showing the operation of the microprocessor in the barcode reading device. 1... Image sensor, 3... Variable gain amplifier circuit,
4... Waveform shaping circuit, 7... Hold circuit, 8...
・A/D converter, 9...Microprocessor representative Yoshihiro Morimoto Figure 2 14 Figure 4

Claims (1)

【特許請求の範囲】[Claims] 1、少なくとも2種類以上の幅をもつバーを順次配列し
たバー記号からなるバーコード上を光学的に走査して複
数ビットの映像信号に変換するイメージセンサと、この
イメージセンサの映像信号を増幅しかつ外部指令信号に
より増幅率を可変される可変利得増幅回路と、この可変
利得増幅回路の離散的映像信号を連続信号に変換する波
形整形回路と、この波形整形回路の連続信号の1走査分
を平均し保持するホールド回路と、前記ホールド回路の
出力信号が所定の範囲内であるか否かの判定を行なう受
光信号レベル判定回路と、この受光信号レベル判定回路
の判定結果に基づき前記可変利得増幅回路の増幅率を指
令して増幅率の設定を行い、設定後、前記ホールド回路
の出力信号が所定の範囲内にある場合に、前記バーコー
ドデータの解読処理を行う判定処理手段とを備えたバー
コード読取装置。
1. An image sensor that optically scans a bar code consisting of a bar symbol in which bars with at least two different widths are sequentially arranged and converts it into a multi-bit video signal, and an image sensor that amplifies the video signal of this image sensor. and a variable gain amplifier circuit whose amplification factor is varied by an external command signal, a waveform shaping circuit that converts the discrete video signal of this variable gain amplifier circuit into a continuous signal, and a waveform shaping circuit that converts one scanning portion of the continuous signal of this waveform shaping circuit. a hold circuit for averaging and holding, a received light signal level determination circuit for determining whether the output signal of the hold circuit is within a predetermined range, and the variable gain amplification based on the determination result of the received light signal level determination circuit. determination processing means for commanding the amplification factor of the circuit to set the amplification factor, and after the setting, for decoding the barcode data if the output signal of the hold circuit is within a predetermined range; Barcode reader.
JP60033304A 1985-02-21 1985-02-21 Bar code reader Pending JPS61193273A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP60033304A JPS61193273A (en) 1985-02-21 1985-02-21 Bar code reader

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP60033304A JPS61193273A (en) 1985-02-21 1985-02-21 Bar code reader

Publications (1)

Publication Number Publication Date
JPS61193273A true JPS61193273A (en) 1986-08-27

Family

ID=12382812

Family Applications (1)

Application Number Title Priority Date Filing Date
JP60033304A Pending JPS61193273A (en) 1985-02-21 1985-02-21 Bar code reader

Country Status (1)

Country Link
JP (1) JPS61193273A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0314190A (en) * 1989-06-13 1991-01-22 Matsushita Electric Ind Co Ltd Bar-code reader
JPH0639634A (en) * 1992-04-24 1994-02-15 Takeo Sakakura Cutter for corner processing and corner processing tool using this cutter
JPH0856390A (en) * 1994-08-12 1996-02-27 Nec Corp Programmable signal conditioner

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5846474A (en) * 1981-09-15 1983-03-17 Nippon Denso Co Ltd Bar code reader
JPS59201175A (en) * 1983-04-28 1984-11-14 Nissan Motor Co Ltd Gain selector circuit of bar code reader

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5846474A (en) * 1981-09-15 1983-03-17 Nippon Denso Co Ltd Bar code reader
JPS59201175A (en) * 1983-04-28 1984-11-14 Nissan Motor Co Ltd Gain selector circuit of bar code reader

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0314190A (en) * 1989-06-13 1991-01-22 Matsushita Electric Ind Co Ltd Bar-code reader
JPH0639634A (en) * 1992-04-24 1994-02-15 Takeo Sakakura Cutter for corner processing and corner processing tool using this cutter
JPH0856390A (en) * 1994-08-12 1996-02-27 Nec Corp Programmable signal conditioner

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