Upconversion Mid Infared Detector for LADAR Application

To address the Navy need for high sensitivity midwave infrared (MWIR) laser detection by sum frequency generation for infrared missile seeker LADAR applications, Physical Optics Corporation (POC) proposes to develop a new Sum Frequency Generation Non-Linear Optical (SUNLO) MWIR LADAR sensor. The proposed device is based on a highly efficient nonlinear optical (NLO) effect created in a NLO crystal combined with high sensitivity silicon-based visible photon counting avalanche photodiodes (APDs). The combination of frequency-shifting to the visible spectrum and high sensitivity detectors provides higher detection efficiency than direct MWIR detectors, quicker response times, and a more compact system, without the need for cryogenic cooling. The detecting sensitivity of SUNLO will be on the order of 10^-14 Joules. The conversion efficiency is about 53% and its bandwidth is 250 GHz with a time constant of about 20 ns. The conversion efficiency is not temperature sensitive. In Phase I POC will design, analyze, and demonstrate the feasibility of the SUNLO MWIR LADAR sensor. In Phase II POC will optimize the detector design and component performance, and will develop and test in a simulated environment a fully functional prototype for use as a missile seeker.