JPS5775480A - Method of measuring threshold current of semiconductor laser and device thereor - Google Patents

Method of measuring threshold current of semiconductor laser and device thereor

Info

Publication number
JPS5775480A
JPS5775480A JP15179780A JP15179780A JPS5775480A JP S5775480 A JPS5775480 A JP S5775480A JP 15179780 A JP15179780 A JP 15179780A JP 15179780 A JP15179780 A JP 15179780A JP S5775480 A JPS5775480 A JP S5775480A
Authority
JP
Japan
Prior art keywords
laser
light
current
frequency
modulation
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
JP15179780A
Inventor
Kenji Sekido
Original Assignee
Nec Corp
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 Nec Corp filed Critical Nec Corp
Priority to JP15179780A priority Critical patent/JPS5775480A/en
Publication of JPS5775480A publication Critical patent/JPS5775480A/en
Application status is Pending legal-status Critical

Links

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/0014Measuring characteristics or properties thereof
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01SDEVICES 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
    • H01S5/00Semiconductor lasers
    • H01S5/06Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068Stabilisation of laser output parameters
    • H01S5/06812Stabilisation of laser output parameters by monitoring or fixing the threshold current or other specific points of the L-I or V-I characteristics

Abstract

PURPOSE:To contrive a simple method of measuring a threshold value and to exactly measure a threshold value by utilizing the fact that the luminous modulation cut off frequency of a semiconductor laser is the difference between the spontaneous emission emitting light and the laser emitting light. CONSTITUTION:Bias current is supplied to a semiconductor laser 1 from the first bias power source 2 through a DC ammeter 3 and a choke coil 4. Furthermore, a modulation signal having higher oscillation frequency than the modulation cut off frequency of the spontaneous emission LED light emitting of the laser 1 and that lower than the modulation cut off frequency of the laser emitting light is generated from a modulation signal power source 5 to superimpose the modulation signal on the bias current of the laser 1 through a capacitor 6. The light output from the laser 1 is received by a light sensitive photo diode 7 and a suitable reverse bias is applied to the light sensitive photo deiode 7 by the second bias current source 10 to supervise a modulated component detected by a detector 12 by a voltmeter 13. And the current of the laser 1 is gradually increased by the power source 2 and a current value detecting or distinguishing a modulation signal component at the light output is measured to use the current value as a threshold value.
JP15179780A 1980-10-29 1980-10-29 Method of measuring threshold current of semiconductor laser and device thereor Pending JPS5775480A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15179780A JPS5775480A (en) 1980-10-29 1980-10-29 Method of measuring threshold current of semiconductor laser and device thereor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15179780A JPS5775480A (en) 1980-10-29 1980-10-29 Method of measuring threshold current of semiconductor laser and device thereor

Publications (1)

Publication Number Publication Date
JPS5775480A true JPS5775480A (en) 1982-05-12

Family

ID=15526501

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15179780A Pending JPS5775480A (en) 1980-10-29 1980-10-29 Method of measuring threshold current of semiconductor laser and device thereor

Country Status (1)

Country Link
JP (1) JPS5775480A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6724205B1 (en) 2002-11-13 2004-04-20 Cascade Microtech, Inc. Probe for combined signals

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6724205B1 (en) 2002-11-13 2004-04-20 Cascade Microtech, Inc. Probe for combined signals
US7046023B2 (en) 2002-11-13 2006-05-16 Cascade Microtech, Inc. Probe for combined signals

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