Secondary Complementary Balancing Compressive Imaging with a Free-Space Balanced Amplified Photodetector.

Area of Science:

• Optics and Photonics
• Computational Imaging
• Signal Processing

Background:

• Single-pixel imaging (SPI) utilizes non-pixelated detectors and digital micromirror devices (DMDs) for image acquisition.
• Complementary balanced measurements enhance signal-to-noise ratio and reconstruction quality in SPI by leveraging complementary modulated patterns from DMDs.
• Optical imbalance between reflection arms critically impacts differential measurement quality in SPI systems.

Purpose of the Study:

• To propose and demonstrate a secondary complementary balancing mechanism for single-pixel imaging.
• To minimize the impact of optical imbalance on SPI system performance.
• To improve the signal-to-noise ratio and image reconstruction quality in SPI.

Main Methods:

• Implementation of a secondary complementary balancing mechanism within an SPI setup.
• Utilizing a silicon free-space balanced amplified photodetector to directly output the difference between optical signals from two reflection arms.
• Conducting both simulation and experimental validation of the proposed balancing method.

Main Results:

• The secondary complementary balancing mechanism effectively cancels direct current components in measurements.
• The proposed method achieves image quality slightly superior to single-arm complementary measurements.
• The system demonstrates over 20 times improvement in image quality compared to dual-pixel complementary measurements under optical imbalance.

Conclusions:

• Secondary complementary balancing is a simple yet effective technique to mitigate optical imbalance in SPI.
• This approach enhances measurement accuracy and image quality in single-pixel imaging systems.
• The developed method offers a robust solution for improving SPI performance, especially in the presence of optical imbalances.