Abstract: An acousto-optic (AO) device includes an AO crystal having a plurality of faces including a first face and a second face. An input transducer bonded to the first face (top electrode) for receiving a radio frequency (RF) signal and launching bulk acoustic waves (BAWs) configured to interact with an optical beam propagating in the AO crystal, wherein the BAWs are received at least in part by the second face after interacting with the optical beam. The second face has a roughened surface portion over an area of at least (?) 50% of an area of the top electrode, and a root mean square (rms) surface roughness?1 ?m and a surface profile derivable from a Fourier transform which provides at least one a first spatial frequency peak from 1 cycle/mm to 300 cycles/mm or at least one band of spatial frequency peaks from 1 cycle/mm to 300 cycles/mm.

Abstract: An acousto-optic (AO) device includes an AO crystal having a plurality of faces including a first face and a second face. An input transducer bonded to the first face (top electrode) for receiving a radio frequency (RF) signal and launching bulk acoustic waves (BAWs) configured to interact with an optical beam propagating in the AO crystal, wherein the BAWs are received at least in part by the second face after interacting with the optical beam. The second face has a roughened surface portion over an area of at least (?) 50% of an area of the top electrode, and a root mean square (rms) surface roughness ?1 ?m and a surface profile derivable from a Fourier transform which provides at least one a first spatial frequency peak from 1 cycle/mm to 300 cycles/mm or at least one band of spatial frequency peaks from 1 cycle/mm to 300 cycles/mm.

Abstract: Two-dimensional or three-dimensional augmented reality (AR) markers are provided for alignment with a target object in calibrating an optical see-through display, such as a head-mounted display (HMD), in an AR system. A calibrated projection matrix for calibration of the optical see-through display is computed based upon a user's repeated alignments of the AR markers with the target object.

Abstract: An acousto-optic (AO) frequency shifter includes an anisotropic crystal having an optical axis and an input face, and an acoustic transducer having electrodes affixed to the face for receiving an electrical signal and projecting an acoustic wave into the crystal. The anisotropic crystal is cut relative to the face so that the transducer is at an acoustic angle (?a) corresponding to a predetermined angle of incidence (?i) of an optical beam to be directed relative to the optic axis of the anisotropic crystal to substantially satisfy the parallel tangents phase matching condition.

Abstract: An acousto-optic (AO) frequency shifter includes an anisotropic crystal having an optical axis and an input face, and an acoustic transducer having electrodes affixed to the face for receiving an electrical signal and projecting an acoustic wave into the crystal. The anisotropic crystal is cut relative to the face so that the transducer is at an acoustic angle (?a) corresponding to a predetermined angle of incidence (?i) of an optical beam to be directed relative to the optic axis of the anisotropic crystal to substantially satisfy the parallel tangents phase matching condition.

Abstract: An acousto-optic modulator includes a (100), (010) or (001) single crystal silicon acousto-optic interaction medium, and at least one transducer for emitting an acoustic wave attached to the single crystal. The transducer has a first electrode layer disposed on one side and a second electrode layer disposed on its other side. The transducer is aligned to the single crystal so that the direction of acoustic propagation in the silicon crystal is substantially along the (100), (010) or (001) direction. A q-switched laser includes a modulator according to the invention.

Abstract: An acousto-optic modulator includes a (100), (010) or (001) single crystal silicon acousto-optic interaction medium, and at least one transducer for emitting an acoustic wave attached to the single crystal. The transducer has a first electrode layer disposed on one side and a second electrode layer disposed on its other side. The transducer is aligned to the single crystal so that the direction of acoustic propagation in the silicon crystal is substantially along the (100), (010) or (001) direction. A q-switched laser includes a modulator according to the invention.