Patent ID: 7403719
Filing Date: 2008-07-22
Classification: H04B

Abstract:
1. An optical system comprising: a) an optical signal input, the optical signal input operable to receive an optical signal and to provide as an output a free-space optical signal; b) a light modulator, comprising a plurality of modulator elements wherein each modulator element is operable to modulate light, positioned to receive the free-space optical signal and operable to modulate the free-space optical signal based upon modulation control signals to provide a modulated free-space optical signal; c) a control circuit in communication with the light modulator, the control circuit operable to generate the modulation control signals for operating the plurality of modulator elements for modulation of the free-space optical signal; and d) an optical alignment detection circuit in electrical communication with the control circuit, wherein the optical alignment detection circuit detects misalignment in the optical system and together with the control circuit is operable to reassign data signals specified for one set of the modulating elements to another set of the modulating elements so as to adjust the modulation control signals to compensate for such misalignment; and e) wherein the optical alignment detection circuit comprises an array of optical detection elements; f) wherein the control circuitry is operable to determine from electrical signals generated by the optical detection elements the approximate location of an alignment optical signal intensity peak striking the optical detection elements; and g) wherein the control circuitry is operable to adjust the modulation control signals by reassigning pixels within the light modulator according to the location of the alignment optical signal intensity; and h) wherein the reassigning pixels within the light modulator is achieved by shifting control of pixels within the light modulator by a fixed number of pixels, wherein the fixed number is responsive to the number of optical detection elements that the alignment optical signal intensity peak is located from a reference point.