A HgCdTe Detector/FPA/Sensor Model for Evaluation of VLWIR to SWIR Sensors with an Assessment of SWIR Sensors for Strategic and Tactical Missions

摘要

This model was developed to provide a means for comparative assessments of HgCdTe FPA's and sensors operating in the infrared spectral bands that coincide with the atmospheric windows -(SW1(1.5-1.8μ), SW2(2-2.5μ), MW(3-5μ), and LW(8-12μ). As a true imaging model it also functions as an assessment tool for single-band imagery and for multi-color imagery. The HgCdTe model characterizes both n-on-p and p-on-n homojunctions and heterostructures. Diffusion and depletion dark currents and RoA's are calculated for the three common configurations (mesa heterojunction, planar ion-implanted or diffused junction, and the vertically integrated photodiode). The model places the specified FPA into an optical system, evaluates system performance (NEI, NETD, MRTD, and SNR) and creates two-point corrected imagery complete with 3D noise image effects. This model was exercised here as a predictive tool for performance of state-of-the-art detector arrays in optical systems in the four spectral bands (atmospheric windows) from the SW to the MW (1.5-1.8, 2.0-2.5, 3.4-4.2 and 4.5-5.0 um) which are the bands commonly considered for hot target and plume exhaust detection. Results from the literature and model runs for various target and scene sets show promise for HgCdTe FPA's and sensors developed for the 2-2.5 um band for a variety of missions such as threat detection from UAV or satellite platforms, perimeter defense, and high-altitude intercepts.