Double focus unity magnification vision system

In order to protect against eye-damaging laser illumination, poer limiting materials have been developed over the past several years. The effective use of these materials requires that the laser radiation be focused to a small and relatively uniform spot within the material in order to "trigger" or activate the material and cuase it to become non-transmissive of the harmful laser light. This requres the incorporation of at least one intermediate focal plant or surface within the optical path, and furthermore, the image quality of this intermediate image must be of adequate quality from an energ density standpoint to be of use. The above task is somewhat straightforward with magnifying sights, binoculars and similar systems. However, it becomes particularly difficult when a unity magnification system is required with a wide field of view. In this SBIR we will develop optical system which provide one and two intermediate images suitable for use with laser limiters. The optical system will operate over an 80 degree field of view at unity magnification. Further, approaches will be investigated to provide two adjacent images of the radiation in order to maximize the efficiency of the limiter.