JPS57172787A - Semiconductor laser protection - Google Patents
Semiconductor laser protectionInfo
- Publication number
- JPS57172787A JPS57172787A JP5753281A JP5753281A JPS57172787A JP S57172787 A JPS57172787 A JP S57172787A JP 5753281 A JP5753281 A JP 5753281A JP 5753281 A JP5753281 A JP 5753281A JP S57172787 A JPS57172787 A JP S57172787A
- Authority
- JP
- Japan
- Prior art keywords
- laser
- circuit
- semiconductor laser
- control loop
- output control
- 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
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)
- Semiconductor Lasers (AREA)
Abstract
PURPOSE:To prevent an overcurrent flowing into a laser by a method wherein an output control loop is provided with a voltage limiting circuit in a semiconductor laser device having the output control loop and a switching circuit is also provided in series with the laser to delay the switch at the time of turning on a power source. CONSTITUTION:When a series circuit consisting of a semiconductor laser LD, a transistor Tr1 and a resistor R1 is formed between a voltage source V and a ground, a switching circuit 4 is inserted between the voltage source V and the laser LD. An output control loop consisting of a photodetector 1, a comparator 2 in which a reference voltage (a) is applied, and an operational amplifier OP1 is provided and a voltage limiting circuit 3 is inserted between the comparator 2 and the amplifier OP1 when the output in the amplifier OP1 is connected to the base of a transistor Tr1. In this composition, the circuit 4 is delayed when a voltage source V is made in hot line condition and the driving current in the laser LD is limited by the circuit 3 to prevent the deterioration or breakdown of the laser LD.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5753281A JPS57172787A (en) | 1981-04-16 | 1981-04-16 | Semiconductor laser protection |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5753281A JPS57172787A (en) | 1981-04-16 | 1981-04-16 | Semiconductor laser protection |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS57172787A true JPS57172787A (en) | 1982-10-23 |
Family
ID=13058352
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP5753281A Pending JPS57172787A (en) | 1981-04-16 | 1981-04-16 | Semiconductor laser protection |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS57172787A (en) |
-
1981
- 1981-04-16 JP JP5753281A patent/JPS57172787A/en active Pending
Similar Documents
Publication | Publication Date | Title |
---|---|---|
FI830701L (en) | SKYDDSKOPPLING FOER EN KOPPLINGSTRANSISTOR | |
ATE212159T1 (en) | SWITCHING POWER SUPPLY WITH OVERCURRENT PROTECTION MEANS | |
DE3377441D1 (en) | Switching power supply with overcurrent protection | |
KR940701595A (en) | Circuit protection device | |
JPS57172787A (en) | Semiconductor laser protection | |
JPS5553183A (en) | Protecting overcurrent of power-switching element in switching power supply | |
EP0182571A3 (en) | Semiconductor switching device | |
JPS56123781A (en) | Electric power control device | |
JPS57102085A (en) | Adjusting method for photo output of semiconductor laser | |
JPS6453611A (en) | Driver circuit | |
JPS55157924A (en) | Overcurrent relay | |
JPS5727084A (en) | Optical transmitter | |
KR960019132A (en) | Optical pickup device protection circuit | |
SU1188873A1 (en) | Method of power transistor switch control | |
KR960002352Y1 (en) | Driving circuit for laser diode | |
JPS5529735A (en) | Temperature detection unit | |
JPS5448030A (en) | Vercurrent protection circuit for swtching regulator | |
JPS57118439A (en) | Short circuit protecting circuit of transistor | |
JPS5754424A (en) | Dirlington connection circuit device for switching | |
JPS5775330A (en) | Overload protecting device | |
JPS6489916A (en) | Output protection device | |
JPS5687389A (en) | Protection of semiconductor laser | |
JPS5480052A (en) | Protecting device for amplifier | |
JPS57138205A (en) | Power amplifier | |
JPS57106473A (en) | Dc welding device |