Powell Prism for optical instruments Powell Prism manufacture precision test and ... angles are 30°,45°,60° and 90°.each optical line generator lens is optimized for a 0.8mm ... line. Specification of Powell Prism:Material:BK7,K9 ,Sapphire,quartz etc.Angle :10°,30°,45°,60°,70°,85°,90 ... to custom design. There are a number of stock optical components in various shapes and sizes to facilitate quick deliveries ...