I am building a laser diode power supply allowing pulse modulation with adjustable pulse width from 2ns to 20ns and repetition rate from 10kHz to 1MHz.
Because of modulation, optical feedback through photo-diode won't work and therefore are not necessary. Correct me if I am wrong.
The laser diode has a threshold current of 10mA and max current of 50mA, and my plan is to look for a power supply (PCB Circuit or bench) with current limit of 30mA. To achieve pulse width 2ns, the power supply must allow modulation up to 500MHz. A square current pulse would be sent from function generator with pulse width of 2ns and current from 0mA to 20mA (0mA because I want the optical power to be completely off) to the power supply.
Do you know the response time of a typical laser diode for injected current from 0mA to be 20mA above the threshould current? I am worried the response time may limit the rise time of the laser pulse (desired to be well below 2ns).
Please comment on the possibility of killing the laser diode. The function generator would produce some spikes, would the current limit from the power supply (either PCB or bench) be able to limit that to avoid damage of the laser diode. And since no regulator is used because modulation, what are the chances that the laser diode be damaged.
Because of modulation, optical feedback through photo-diode won't work and therefore are not necessary. Correct me if I am wrong.
The laser diode has a threshold current of 10mA and max current of 50mA, and my plan is to look for a power supply (PCB Circuit or bench) with current limit of 30mA. To achieve pulse width 2ns, the power supply must allow modulation up to 500MHz. A square current pulse would be sent from function generator with pulse width of 2ns and current from 0mA to 20mA (0mA because I want the optical power to be completely off) to the power supply.
Do you know the response time of a typical laser diode for injected current from 0mA to be 20mA above the threshould current? I am worried the response time may limit the rise time of the laser pulse (desired to be well below 2ns).
Please comment on the possibility of killing the laser diode. The function generator would produce some spikes, would the current limit from the power supply (either PCB or bench) be able to limit that to avoid damage of the laser diode. And since no regulator is used because modulation, what are the chances that the laser diode be damaged.