Improvements in birefringent filters. 5: Field of view effects.

The field of view characteristics of wide field birefringent (WFB) elements are compared with those of the Fabŕy-Perot (F.P.), Michelson (MI), and wide field Michelson (WFM) interferometers. Throughput gains of 50 to 300 or more with respect to the F.P. or MI are demonstrated. Further, it is shown that by proper choice of material WFB elements can have angular characteristics identical with WFM interferometers. The properties of misaligned and mismatched half-length WFB elements are calculated. It is shown that properly misadjusted WFB elements can exhibit throughput gains with respect to properly adjusted systems. Finally, a catalog of fringe patterns for WFB elements of different materials and differing angular misadjustment is presented.