Patent ID: 8916813
Filing Date: 2014-12-23
Classification: G01J

Abstract:
1. A balanced optical cross correlator comprising: an optical waveguide including an input end, an output end, and a point of symmetry between the output end and the input end; a first photodiode including a first n-type semiconductor and a first p-type semiconductor positioned about the optical waveguide on a first side of the optical waveguide's point of symmetry; a second photodiode including a second n-type semiconductor and a second p-type semiconductor positioned about the optical waveguide on a second side of the optical waveguide's point of symmetry; a balanced receiver including a first input and a second input, with inputs having identical polarities or opposite polarities, and configured to produce an output current or voltage that reflects a difference in currents or voltages fed to the first input and to the second input; a first electrically conductive pathway coupling the first input of the balanced receiver with the first n-type semiconductor or with the first p-type semiconductor; and a second electrically conductive pathway, wherein: (I) in the case of the balanced receiver having identical input polarities, the second electrically conductive pathway couples the second input of the balanced receiver (a) with the second n-type semiconductor if the first electrically conductive pathway couples the first input with the first p-type semiconductor or (b) with the second p-type semiconductor if the first electrically conductive pathway couples the first input with the first n-type semiconductor; or (II) in the case of the balanced receiver having opposite input polarities, the second electrically conductive pathway couples the second input of the balanced receiver (a) with the second n-type semiconductor if the first electrically conductive pathway couples the first input with the first n-type semiconductor or (b) with the second p-type semiconductor if the first electrically conductive pathway couples the first input with the first p-type semiconductor.