Self-mixing sensing system based on uncooled vertical-cavity surface-emitting laser array: linking multichannel...

Area of Science:

• Optoelectronics
• Laser Sensing Technology
• Semiconductor Devices

Background:

• Self-mixing (SM) sensing utilizes laser feedback for measurement.
• Vertical-cavity surface-emitting lasers (VCSELs) offer compact and scalable laser sources.
• Uncooled sensor arrays are desirable for simplified and cost-effective systems.

Purpose of the Study:

• To compare the performance of a 24x1 monolithic VCSEL array in single-channel versus multichannel self-mixing operation.
• To investigate the impact of multichannel operation on sensor signal-to-noise ratio (SNR).
• To explore the potential for high-resolution, uncooled imaging systems using VCSEL arrays.

Main Methods:

• Utilized a 24x1 monolithic array of vertical-cavity surface-emitting lasers (VCSELs).
• Compared self-mixing sensor performance in single active channel mode versus concurrent multichannel operation.
• Analyzed the signal-to-noise ratio (SNR) of individual sensors under different operational modes.
• Investigated the effect of sensor operational temperature on performance.

Main Results:

• Concurrent multichannel operation markedly improved the signal-to-noise ratio (SNR) of individual SM sensors.
• The performance enhancement in multichannel mode is attributed to increased operational temperature of the VCSEL sensors.
• Further performance gains are achievable with VCSEL arrays featuring smaller inter-device pitch.
• The findings suggest potential for high spatial and temporal resolution imaging without active temperature stabilization.

Conclusions:

• Multichannel operation of SM VCSEL arrays offers a significant advantage in sensor SNR.
• Increased operational temperature in multichannel mode is key to performance improvement.
• Optimizing VCSEL array pitch can further enhance imaging system capabilities.
• This technology paves the way for advanced, uncooled, high-resolution optical sensing systems.