JPS56155473A - Detection for signal light - Google Patents

Detection for signal light

Info

Publication number
JPS56155473A
JPS56155473A JP5879780A JP5879780A JPS56155473A JP S56155473 A JPS56155473 A JP S56155473A JP 5879780 A JP5879780 A JP 5879780A JP 5879780 A JP5879780 A JP 5879780A JP S56155473 A JPS56155473 A JP S56155473A
Authority
JP
Japan
Prior art keywords
signal
light
frequency
modulation
signal light
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
JP5879780A
Other languages
Japanese (ja)
Inventor
Osamu Hasegawa
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP5879780A priority Critical patent/JPS56155473A/en
Publication of JPS56155473A publication Critical patent/JPS56155473A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10544—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum
    • G06K7/10821—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum further details of bar or optical code scanning devices
    • G06K7/10851—Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)

Abstract

PURPOSE:To eliminate the influence of the disturbance light, by making the modulation frequency of the irradiation light higher than the frequency of the signal and by filtering the signal light by the same frequency as the modulation frequency to read the signal, in the signal light detection method. CONSTITUTION:The irradiation light is subjected to high-frequency modulation by, for example, 100kHz. The reflected light from the object is detected by the photodiode. Actually, the signal light like (c) is obtained due to the disturbance light. The signal like (c) is filtered by the machanical filter of resonance frequency 100kHz. This filtered signal is caused to pass through the rectifying circuit and is subjected to AC amplification and is caused to pass through the limiter circuit, thereby detecting the signal. Consequently, since the influence of the disturbance light is eliminated by passage through the filter, the read precision of the bar code is improved if this method is adopted in the bar code reader.
JP5879780A 1980-05-02 1980-05-02 Detection for signal light Pending JPS56155473A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5879780A JPS56155473A (en) 1980-05-02 1980-05-02 Detection for signal light

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5879780A JPS56155473A (en) 1980-05-02 1980-05-02 Detection for signal light

Publications (1)

Publication Number Publication Date
JPS56155473A true JPS56155473A (en) 1981-12-01

Family

ID=13094566

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5879780A Pending JPS56155473A (en) 1980-05-02 1980-05-02 Detection for signal light

Country Status (1)

Country Link
JP (1) JPS56155473A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5915936A (en) * 1982-07-19 1984-01-27 Asahi Chem Ind Co Ltd Manufacture of substrate having through hole
JPH02267682A (en) * 1989-02-28 1990-11-01 Gold Star Co Ltd Bar code reader
JPH03233692A (en) * 1990-02-08 1991-10-17 Sumitomo Electric Ind Ltd Bar code reader

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5915936A (en) * 1982-07-19 1984-01-27 Asahi Chem Ind Co Ltd Manufacture of substrate having through hole
JPH02267682A (en) * 1989-02-28 1990-11-01 Gold Star Co Ltd Bar code reader
JPH03233692A (en) * 1990-02-08 1991-10-17 Sumitomo Electric Ind Ltd Bar code reader

Similar Documents

Publication Publication Date Title
ATE49074T1 (en) DEVICE FOR DETECTING A SECURITY THREAD EMBEDDED IN A PAPER-LIKE MATERIAL.
GB1484353A (en) Electronic security systems incorporating noise rejection circuitry
JPS56155473A (en) Detection for signal light
JPS57208465A (en) Discriminating circuit for frequency
JPS5737907A (en) Fm wave detector
JPS5718139A (en) In-band signal detecting device
JPS539443A (en) Test system for electronic package
JPS56110347A (en) Am receiver
SU959294A1 (en) Receiver of multifrequency signals
JPS5593369A (en) Detector for control signal
SU1037205A1 (en) Automatic control system filter
SU434378A1 (en) DEVICE FOR DETERMINING A SIGNAL SIGNAL CALCULATION IN EXTREME SYSTEMS
SU1117672A1 (en) Capacitive-type alarm system
EP0085625A3 (en) Filtering and frequency detection circuits for delta modulated signals
JPS5773635A (en) Photoelectric detector
JPS5637568A (en) Noise rejection system in corona detection apparatus
JPS5731274A (en) Detecting circuit of noise band phase
SU1439468A1 (en) Device for contactless check of wear of cutting tool in machining process
SU851210A1 (en) Puncture indicator
JPS56100381A (en) Human body detector of electric field type
JPS56109020A (en) Signal processor
JPS6420485A (en) Human body detector
JPS56153871A (en) Receiving system for signal-frequency signal
JPS56154862A (en) Receiving method of wireless equipment
JPS5787243A (en) Signal detecting circuit