Patent ID: 7916304

Claim:
An apparatus, comprising: an optical system having a beam splitter device and at least three detectors, the optical system configured to produce a plurality of images of an optical source in a first dimension and a second dimension substantially orthogonal to the first dimension based on an interference of an emission of the optical source in a first direction and an emission of the optical source in a second direction, the second direction being different from the first direction, the beam splitter device configured to interfere the emission in the first direction and having a first source phase and the emission in the second direction and having a second source phase to produce at least three output beams, the at least three optical detectors configured to detect optical energy from the at least three output beams of the beam splitter device, each detector from the at least three detectors being uniquely associated with an image from the plurality of images at a time; and a processor configured to calculate a position of the optical source in a third dimension based on the plurality of images, the third dimension being substantially orthogonal to the first dimension and the second dimension; the interference between the emission of the optical source in the first direction and the emission of the optical source in the second direction being caused at least in part by a difference in path length between the emission in the first direction and the emission in the second direction.