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Laser modulation clarification needed

Laser modulation clarification needed

Laser modulation clarification needed


I need professional help in clarification of what happens to laser when it is modulated in my particular case. I will be using e.g. 200mW 808nm laser. It is not pulsed laser, CW. I will feed current from current controller. Besides, I will modulate current controller output with function generator, and modulation will be e.g. 50kHz and 6-16 microseconds (or even in milliseconds range) pulse widths. I am wondering what will be the power of the pulses (pulse/peak power)? Will if follow the rule that peak power=average power/duty cycle? Or does this rule apply only in cases when ns and ps pulses are used?

Thank you!

RE: Laser modulation clarification needed

Your "rule" is actually less accurate for shorter pulses, as they might not be nice, perfect, square waves. Nevertheless, the average power is the average power of a pulse multiplied by the duty cycle --> power*pulse time = energy/pulse energy/pulse / pulse cycle time = power/pulse cycle time = average power

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RE: Laser modulation clarification needed

Thank you IRstuff,

So do you mean that this rule is working for micro- and milliseconds pulses? Or it is even not pulses but a modulation of CW laser. I am still a bit confused because some sources say that the rule is applicable only for pulsed lasers (which are not CW initially) but some say that it for both, but in case of modulated CW laser rule works only for up to 100 ns pulses...

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