High-speed 2D and 3D mid-IR imaging with an InGaAs camera

Area of Science:

• Optics and Photonics
• Materials Science
• Semiconductor Physics

Background:

• Non-degenerate two-photon absorption (NTA) enables mid-infrared (MIR) imaging with standard silicon cameras.
• Silicon's low nonlinear absorption limits imaging speed, especially at lower illumination levels.
• Existing NTA-based MIR imaging lacks speed for dynamic applications.

Purpose of the Study:

• To enhance the speed of non-degenerate two-photon absorption (NTA) based mid-infrared (MIR) imaging.
• To overcome the limitations of silicon photosensors for faster MIR detection.
• To enable high-speed 2D or 3D MIR mapping without complex image processing.

Main Methods:

• Utilized indium gallium arsenide (InGaAs) as the photosensor material for MIR detection.
• Leveraged the significantly higher nonlinear absorption coefficient of InGaAs compared to silicon.
• Implemented high-speed imaging techniques to capture frames rapidly.

Main Results:

• Demonstrated high-speed MIR imaging at frame rates up to 500 frames per second (fps).
• Achieved imaging with exposure times under 1 millisecond per frame.
• Successfully enabled 2D or 3D MIR mapping without the need for pre- or post-image processing.

Conclusions:

• Indium gallium arsenide (InGaAs) is a superior photosensor for high-speed non-degenerate two-photon absorption (NTA) based mid-infrared (MIR) imaging.
• The developed InGaAs-based system offers a significant advancement in MIR imaging speed and efficiency.
• This technology facilitates rapid, high-resolution 2D and 3D mapping in the MIR spectrum.