Simple low power nanosecond pulses from a continuous wave diode laser.

Area of Science:

• Optoelectronics
• Semiconductor device physics
• Pulse generation

Background:

• Continuous wave diode lasers are widely used but achieving ultra-short pulse generation requires complex modulation.
• Existing methods for generating sub-nanosecond pulses often involve expensive or bulky equipment.

Purpose of the Study:

• To develop a simple and low-cost method for generating sub-nanosecond laser pulses.
• To utilize the intrinsic properties of electronic components for optical pulse shaping.

Main Methods:

• A low power continuous wave diode laser was modulated by exploiting the propagation delay and slew rate of a transistor-transistor logic (TTL) inverter.
• Overlapping TTL pulses were generated to activate an AND gate, effectively shaping the laser output.

Main Results:

• Sub-nanosecond laser pulses were successfully generated.
• The system achieved user-controlled repetition rates up to 100 KHz.
• The modulation method proved effective for precise pulse timing.

Conclusions:

• The proposed technique offers a straightforward and economical approach to generating high-repetition-rate, sub-nanosecond laser pulses.
• This method has potential applications in areas requiring precise optical timing, such as optical communications and sensing.