Patent ID: 6625378
Filing Date: 2003-09-23
Classification: G02B,G02F

Abstract:
A variable optical attenuator device comprising:a first electrically conductive electrode that is transparent to an optical wavelength of input light; a second electrically conductive electrode that is reflective to said optical wavelength of said input light; an electrochromic attenuator interposed between said first and second electrically conductive electrodes, and having electrochromic attenuation properties thereof controllably adjustable in accordance with respective electrical potentials applied to said first and second electrically conductive electrodes; a light input interface configured to direct said input light along at least one input optical path that is incident upon said first electrically conductive electrode and extends through said first electrically conductive electrode and said electrochromic attenuator, so that said input light traveling along said at least one input optical path reflects from said second electrically conductive electrode along at least one exit optical path through said electrochromic attenuator and aid first electrically conductive electrode, and exits said electrically conductive electrode; and a light output interface configured to extract output light from light traveling along said at least one exit optical path and exiting said first electrically conductive electrode, and wherein said light output interface is configured to direct said output light extracted by said light output interface along a further optical path, cascaded with said exit optical path and incident upon said first electrically conductive electrode and extending through said first electrically conductive electrode and said electrochromic attenuator, so that said extracted output light travels along said further optical path and reflects from said second electrically conductive electrode along a further exit optical path through said electrochromic attenuator and said first electrically conductive electrode and exits said first electrically conductive electrode.