SBIR-STTR Award

Missile Defense surveillance and interceptor sensor operations typically use cryogenically cooled infrared sensors that operate while being exposed to natural space radiation and possibly to nuclear weapon radiation, both of which have the potential to degrade system performance. USASMDC's Hardened Infrared Optical Components (HIROC) program test results indicate that cryogenically cooled optical filters are susceptible to low levels of ionizing radiation dose, and thus pose a potential problem in an operational scenario. A solution to this problem requires the development of radiation hardened infrared optical filters. The GH Systems' team, including Surface Optics Corporation and ATK Mission Research, is proposing a multi-phase program to develop and commercialize radiation hardened IR filters. The proposed Phase I effort will investigate the radiation damage mechanisms, develop strategies to fabricate radiation hardened IR filters, develop an overall technology development and test plan, and perform limited radiation testing and material characterization. Our planned Phase II efforts will include the finalization of radiation hardened design approaches, fabrication of filters, and radiation testing to provide design verification. The GH Systems' team plans to use current commercial processes to develop this radiation hardened optical filter providing prompt availability to MDA.

Keywords:
Materials, Processes, Sensors, Radiation Hardened, Infrared, Optical Filters, Hardened Fpas, Electro-Optical Subsystems

Critical space and missile defense systems include high performance infrared (IR) sensors consisting of cryogenically cooled IR focal plane arrays and IR band-pass filters, which are both degraded by ionizing radiation. One aspect of this problem is the absence of intentionally radiation hardened by design (RHBD) cryogenic IR band-pass filters. The current filters used in IR sensors are either radiation soft or radiation hard by accident. All of the previous proposed solutions to prevent radiation induced darkening of IR filters have been shown to be invalid. This leaves IR sensor designers with two options: 1) Complete the development of radiation hardened by design cryogenic IR filters, or 2) iteratively develop, fabricate, and characterize IR filters in the hope that some are accidentally radiation hard enough. Option 1 will provide MDA and other agencies with intentionally radiation hardened designs capable of operation in environments that exceed total doses of 100 krad(Si). Subsequent programs may then choose a rad-hard by design filter, resulting in reduced cost and schedule risks to the program. Option 2 will not only dramatically increase cost and schedule risks, but it will also leave the space and radiation community without a known solution and only limited radiation hardness.

Keywords:
Infrared, Ir, Band-Pass Filter, Radiation Hardened, Focal Plane Array, Zns, Lwir