Gam Prototypes of electromagnetic shutters of two types are being field tested as a part of this program. These shutters are designed to prevent or minimize temporary flash blindness, after-images, or retinal burns. Results obtained on animals exposed behind these shutters will be compared with those obtained by other shutters and filter mechanisms. None of the animals exposed had eyes held open by artificial means, This introduced the possibility that the eye might be closed at time zero. An alarm bell was set up to waken animals. focused on the animals were used to determine shutter Cameras speed and to ascertain whether eyes were open during the time of exposure. RESULTS An examination of the exposed eyes of the animals revealed no chorioretinal burns, rabbits were dead. Of the 83 rabbits and 8 monkeys exposed, 4 Inspection of the equipment at time of re-entry indicated that it had functioned properly, A check of actual shutter speeds must wait availability and study of the high speed motion pictures. CONCLUSIONS It is not believed that lack of chorioretinal burns can be attributed to the change in detonation point of the weapon, The absence of eye injury is very probably due to the animals receiving a total thermal energy lower than had been calculated, and delivery of this energy over a much greater time interval. The normal blink reflex time, as determined in laboratory tests, would permit these experimental animals to have their eyes closed by the beginning of the second pulse. Animal deaths are attributed to sun stroke or heat prostration induced by the prolonged period of exposure to the afternoon sun after 1400 on D-l. - This project has received the wholehearted cooperation iy la 52 yl