JPS6459879A - Semiconductor laser protective circuit - Google Patents

Semiconductor laser protective circuit

Info

Publication number
JPS6459879A
JPS6459879A JP62216829A JP21682987A JPS6459879A JP S6459879 A JPS6459879 A JP S6459879A JP 62216829 A JP62216829 A JP 62216829A JP 21682987 A JP21682987 A JP 21682987A JP S6459879 A JPS6459879 A JP S6459879A
Authority
JP
Japan
Prior art keywords
driving current
semiconductor laser
excessive
current
breaking
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
JP62216829A
Other languages
Japanese (ja)
Inventor
Noriji Sasaki
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 JP62216829A priority Critical patent/JPS6459879A/en
Publication of JPS6459879A publication Critical patent/JPS6459879A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068—Stabilisation of laser output parameters
    • H01S5/06825—Protecting the laser, e.g. during switch-on/off, detection of malfunctioning or degradation

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optics & Photonics (AREA)
  • Optical Head (AREA)
  • Semiconductor Lasers (AREA)
  • Optical Communication System (AREA)

Abstract

PURPOSE:To protect a semiconductor laser from breakdown when excessive driving current is applied, by detecting and breaking the driving current of the semiconductor laser momentarily. CONSTITUTION:Driving current is converted to voltage by an amplifier 4 then the value thereof is compared with a reference voltage Vref2 by a comparator 7. When excessive driving current is supplied to LD1, the driving current to LD1 is broken at once and LD1 is thereby prevented from breakdown due to excessive current. Since the reference voltage Vref2 is controlled by a temperature detecting element 8 and a voltage controlling circuit 9 according to ambient temperature change, light output is maintained constant by the threshold value current change of LD1 due to the temperature change. Therefore, if driving current increases, it can be prevented from breaking by error. If the excessive driving current is partial, driving current can be supplied again to LD1 after a specified time period.
JP62216829A 1987-08-31 1987-08-31 Semiconductor laser protective circuit Pending JPS6459879A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62216829A JPS6459879A (en) 1987-08-31 1987-08-31 Semiconductor laser protective circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62216829A JPS6459879A (en) 1987-08-31 1987-08-31 Semiconductor laser protective circuit

Publications (1)

Publication Number Publication Date
JPS6459879A true JPS6459879A (en) 1989-03-07

Family

ID=16694546

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62216829A Pending JPS6459879A (en) 1987-08-31 1987-08-31 Semiconductor laser protective circuit

Country Status (1)

Country Link
JP (1) JPS6459879A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0428463U (en) * 1990-07-02 1992-03-06
KR100240281B1 (en) * 1997-05-20 2000-03-02 서평원 An automatic optical output regulating system and an alarm system
EP0993089A3 (en) * 1998-10-05 2004-04-14 Canon Kabushiki Kaisha Laser control apparatus, image forming apparatus and copier
JP2005011390A (en) * 2003-06-16 2005-01-13 Samsung Electronics Co Ltd Optical disc apparatus and laser output control method
JP2009200242A (en) * 2008-02-21 2009-09-03 Fujitsu Ltd Optical transmitter, and control method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0428463U (en) * 1990-07-02 1992-03-06
KR100240281B1 (en) * 1997-05-20 2000-03-02 서평원 An automatic optical output regulating system and an alarm system
EP0993089A3 (en) * 1998-10-05 2004-04-14 Canon Kabushiki Kaisha Laser control apparatus, image forming apparatus and copier
JP2005011390A (en) * 2003-06-16 2005-01-13 Samsung Electronics Co Ltd Optical disc apparatus and laser output control method
JP2009200242A (en) * 2008-02-21 2009-09-03 Fujitsu Ltd Optical transmitter, and control method
EP2093849A3 (en) * 2008-02-21 2010-03-17 Fujitsu Limited Optical transmitter

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