OPTICAL PROTECTION FROM NUCLEAR THERMAL ENERGY

OPTICAL DEVICES MAY BE EXPOSED TO DIRECT OR INDIRECT THERMAL RADIATION FROM FIREBALLS ON THE TACTICAL NUCLEAR BATTLEFIELD. THE FIREBALL THERMAL RADIATION PERSISTS FOR SEVERAL SECONDS, DEPENDING ON THE YIELD AND DETONATION ALTITUDE OF THE NUCLEAR WEAPON. THE TOTAL BLACKBODY FLUENCE RADIATED TO THE VICINITY OF AN OPTICAL DEVICE MAY BE WELL IN EXCESS OF THE LEVEL AT WHICH CRITICAL COMPONENTS OF THE DEVICE FAIL AS A RESULT OF EXCESSIVE TEMPERATURE RISE, MATERIAL DEGRADATION, OR OTHER MECHANISMS. THE FEASIBILITY OF USING VARIOUS TECHNIQUES, INCLUDING PHOTOCHROMICS AND ELECTROCHROMICS, TO PROTECT THE SENSITIVE OPTICAL DEVICES FROM FIREBALL THERMAL RADIATION WILL BE ASSESSED. THE RELATIVE PROTECTION AFFORDED BY THE TECHNIQUES AND THE PENALTIES ASSOCIATED WITH OPEN-STATE, OR BENIGN, PERFORMANCE WILL BE INVESTIGATED. PROTECTION FOR SEVERAL CLASSES OF OPTICAL DEVICES WILL BE INCLUDED IN THE STUDY. DISTINCTION WILL BE MADE AMONG NARROW AND BROAD-BAND SENSORS AND SPECIFIC POTENTIAL FAILURE MODES AND LEVELS. HUMAN EYE PROTECTION WILL BE CONSIDERED IN CONJUNCTION WITH SPECIFIC OPTICAL DEVICES. HARRY DIAMOND LABORATORIES WILL PROVIDE SUPPORT IN THE INITIAL PERIOD OF THE EFFORT TO DEFINE SPECIFIC DEVICES AND THEIR OPTICAL CHARACTERISTICS.