j= Legg oss) Project 4.1 -— Flash Blindness - Chorioretinal Burns - Col. R.S. Fixott OBJECTIVES The primary objective of this project is to obtain information on the requirements for protection of the eyes egainst chorioretinal burns from atomic detonations of various yields; enliig meee Corollary technical objectives at the same yield are to: Determine whether blink reflexes will prevent chorioretinal burns. Ascertain which portions of the time-intensity pulse can produce thermal injury to the retina and choroid of the eye. Determine the time required for blink reflex (BRT) in rabbits and monkeys exposed to the extreme light intensity of the atomic detonation. Explore the feasibility of ocular protection by means of fixed density optical filters and/or corbinations of filters. Test, under field conditions, protective shutter devices which are in the developmental stege and which are designed to close much more rapidly than the BRT, INSTRUMENTATION The basic instrumentation for this shot was identical to that used for previous shots. In addition instrumentation on loan from Project 2.65 (Army Chemical Center) was employed for measuring the thermal radiation dosage received at exposure sites on Jeptan (David) and Runit (Yvonne). This instrument gives no informetion on pulse shape. General Cbhservations Chorioretinel burns were produced in 19 of 92 rabbits end 8 of 8 monkeys participating in this shot, e ~entbe All cf the burns were produced at the Runit site. - 27 - —_