Precise control of broadband frequency chirps using optoelectronic feedback.

Area of Science:

• Optoelectronics
• Laser Physics
• Photonics

Background:

• Swept-frequency lasers are crucial for applications like laser ranging and 3-D imaging.
• Existing swept-frequency sources often lack agility and precise control over sweep characteristics.

Purpose of the Study:

• To demonstrate a novel method for generating wideband optical frequency sweeps using a semiconductor laser.
• To achieve agile and high-coherence swept-frequency light sources controlled by electronic signals.

Main Methods:

• Utilizing a semiconductor laser within an optoelectronic feedback loop.
• Locking the optical frequency sweep rate and shape to a reference electronic signal frequency.
• Demonstrating arbitrary sweep generation by tuning the electronic reference signal.

Main Results:

• Achieved a transform-limited linear frequency sweep of 100 GHz in 1 ms.
• Demonstrated real-time laser ranging with a spatial resolution of 1.5 mm.
• Successfully generated broadband quadratic and exponential optical frequency sweeps.

Conclusions:

• The demonstrated optoelectronic feedback technique provides an agile, high-coherence swept-frequency source.
• This method offers precise control over sweep characteristics for advanced laser applications.
• The system is suitable for high-resolution 3-D imaging and laser ranging.