Parallel self-mixing imaging system based on an array of vertical-cavity surface-emitting lasers.

Area of Science:

• Optics and Photonics
• Fluid Dynamics
• Measurement Science

Background:

• Traditional surface profiling and flowmetry methods can be limited in speed and scope.
• Self-mixing interferometry offers a compact and potentially low-cost sensing approach.
• Massively parallel systems are needed for real-time, high-resolution measurements.

Purpose of the Study:

• To investigate the feasibility of a massively parallel self-mixing imaging system.
• To develop a system capable of measuring displacement, distance, velocity, and liquid flow rate.
• To demonstrate the system's capability using a prototype.

Main Methods:

• Utilized an array of vertical-cavity surface-emitting lasers (VCSELs).
• Developed a prototype for parallel self-mixing imaging.
• Applied the system to measure radial velocity on a rotating disk.
• Measured the velocity profile of diluted milk in a custom flow channel.

Main Results:

• Demonstrated the concept of the parallel self-mixing imaging system.
• Successfully measured velocity at various radial points on a rotating disk.
• Obtained the velocity profile of diluted milk in a planar flow channel.

Conclusions:

• The massively parallel self-mixing imaging system is feasible for various measurement tasks.
• The prototype validates the system's potential for velocity and flow rate measurements.
• A scaled-up system could enable real-time surface profiling, vibrometry, and flowmetry.