Abstract
A 1D IR lock-in focal plane array (FPA) for extremely weak signal imaging has been demonstrated. The experimental system consists of an object with modulated image signal, a high speed InGaAs linear photodetector array as receiver, a CMOS lock-in linear array read-out circuit, and a focal plane array test system. The system can detect extremely weak signals immersed in strong background. Preliminary test shows that under room temperature each of the pixels in the ID lock-in FPA can read out modulated signal S orders smaller than the background. The InGaAs detector array response is from 0.8 μm to 1. 6 μm (peak at 1.2 μm). The lock-in array read-out circuit uses a correlated multi-cycle integrator, which can operate in several modes such as gated integration, and phase-sensitive integration with background subtraction. The ID lock-in FPA works as a pixel to pixel lock-in amplifier, wherein very small signals may be extracted from a much strong background if the frequency of the illuminating source (usually IR light sources) is known. Simulation results are also reported. Experimental results based on an IR illuminating source are demonstrated.
Original language | English (US) |
---|---|
Pages (from-to) | 64-72 |
Number of pages | 9 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5406 |
Issue number | PART 1 |
DOIs | |
State | Published - 2004 |
Event | Infrared Technology and Applications XXX - Orlando, FL, United States Duration: Apr 12 2004 → Apr 16 2004 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering
Keywords
- FPA
- LI-FPA
- LIA
- LPA
- LPF
- PSD
- QWIP
- Read-out