CPC G02F 1/13471 (2013.01) [G02B 5/208 (2013.01)] | 3 Claims |
1. A non-mechanical liquid crystal tunable filter (LCTF) assembly comprising:
a first LCTF component comprising:
a first optical filter comprising a first optical axis,
a second optical filter comprising a second optical axis, wherein the second optical axis is rotated 90° relative to the first optical axis, and
a first twisted nematic cell positioned between the first optical filter and the second optical filter, the first twisted nematic cell configured to polarize received light by 90° when a first voltage is not applied and not polarize the received light when the first voltage is applied; and
a second LCTF component comprising:
a third optical filter comprising a third optical axis,
a fourth optical filter comprising a fourth optical axis, wherein the fourth optical axis is rotated 90° relative to the third optical axis, and
a second twisted nematic cell positioned between the third optical filter and the fourth optical filter, the second twisted nematic cell configured to polarize received light by 90° when a second voltage is not applied and not polarize the received light when the second voltage is applied;
wherein the non-mechanical LCTF assembly is configured to switch between a conformal filter mode and a multi-conjugate filter mode based on whether the first voltage is applied to the first LCTF assembly, the second voltage is applied to the second LCTF assembly, or a combination thereof, and
wherein a first one of the first optical filter, the second optical filter, the third optical filter, and the fourth optical filter comprises a Pi cell.
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