Patent ID: 8854713

Claim:
A power selective optical filter device, comprising: an input polarizer having a transmission axis, the input polarizer configured to selectively transmit at least a portion of an input signal therethrough, wherein the at least a portion of the input signal exhibits a polarization state and a power; a wave-plate structure positioned to receive the at least a portion of the input signal, the wave-plate structure including: at least a first substantially zero-order, zero-wave plate configured to alter the polarization state of the at least a portion of the input signal passing therethrough in a manner that is dependent on the power of the at least a portion of the input signal, the at least a first substantially zero-order, zero-wave plate including: an entry wave plate having a fast axis; and an exit wave plate having a fast axis, the fast axis of the entry wave plate oriented at a predetermined angle relative to the fast axis of the exit wave plate, the entry wave plate of the first substantially zero-order, zero-wave plate oriented relative to the transmission axis of the input polarizer at a selected entry-wave-plate angle; and an output polarizer positioned to receive the polarization-state-altered signal output from the wave-plate structure, the output polarizer configured to selectively transmit at least a portion of the polarization-state-altered signal based on the polarization state thereof.