The power of laser diodes, made of GaAs, is limited by its power loss and the maximum operating temperature. Theoretically, the semiconductor material itself can be operated up to an intrinsic temperature of 650°C. Practically the operating temperature is limited at 250°C, because the electrical contacts, made by soldering with a high lead solder (300°C melting temperature).
the question is how can make or let this component to work with high temperature is that by electrical contacts in attaches in a circuit?
That's which allow an application with a maximum of operating temperature and of course i have to consider to and ensure the thermal expansion and the mechanical stability.
Electrical – Laser Diodes to work it in high temperature
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Related Solutions
High temperature LEDs do exist in SMD form factors: Look for LEDs with full ceramic substructure and high temperature bonds (typically silver or silver-plated). These are designed to withstand temperatures up to and above 125 degrees Centigrade.
One such example is the ROHM PSL01 LED, that is rated for operation up to 130 degrees C.
One way is to use a single 36 V power supply, then essentially a small switching power supply for each LED to regulate the current thru each LED separately, but driven from PWM.
Here is what the circuit for each LED would be:
When the switch is closed, current builds up linearly thru L1 and therefore thru the LED. When the switch is opened, the current continues thru the LED, L1, but now thru D2. The current will now ramp down linearly.
With fast enough PWM there is little difference between the maximum current at the end of the switch closed time, and the minimum current at the end of the switch open time. The PWM duty cycle then controls the average current thru the LED with minor ripple at the PWM frequency.
You probably want to use a PWM frequency of a MHz or more. For extra filtering, add a ceramic capacitor from the LED cathode to ground.
Best Answer
Several things:
The power of a laser diode may be limited by the light intensity causing damage to the facets, independently of the thermal effects. The datasheet should tell you both the maximum instantaneous (optically limited) power and the maximum average (thermally limited) power.
Attempting to run more current through the diode may not be effective because at a certain point you may run out of charge carriers. At higher voltages the charge carriers may also be pulled out of the active region so they are not in a good location to lase. (I am guessing here.)
Also, if your device is not designed to operate at high temperatures, it may not act properly due to the number of holes and electrons popped out of the Fermi sea by thermal effects: the free carriers act metalish instead of semiconductorish and just conduct without providing any light. Even at more conventional temperatures, laser diode efficiency drops significantly just going from 20C to 50C.