US 7,733,469 B2 · Image null-balance system with multisector-cell direction sensing

Abstract

A light beam is detected/localized by multisector detector—quad-cell, or 5+ sectors handling plural beams. Preferences: Beams focus to diffraction limit on the detector, which reveals origin direction by null-balance—shifting spots to a central sector junction, and measuring shifts to reach there. One or more MEMS reflectors, and control system with programmed processor(s), sequence the spot toward center: following a normal to an intersector boundary; then along the boundary. One afocal optic amplifies MEMS deflections; another sends beams to imaging optics. After it's known which sector received a spot, and the beam shifts, source direction is reported. The system can respond toward that (or a related) direction. It can illuminate objects, generating beams reflectively. Optics define an FOR in which to search; other optics define an FOV (narrower), for imaging spots onto the detector. The FOR:FOV angular ratio is on order of ten—roughly 180:20°, or 120:10°.

Claims33

Dependent claims

Apparatus for detecting, and determining the direction of, an incident beam of light;

said apparatus comprising:
a multiple-sector-cell detector;
optics for forming a sharply focused image of such beam on the multiple-sector-cell detector;
and
means, responsive to the multiple-sector-cell detector, for determining the direction of origin of such beam, wherein the direction-determining means:
interact with the detector in a null-balance mode of operation;
and
comprise means for:
deflecting the sharply focused image to a central position substantially common to the multiple sectors, and
measuring the amount of deflection required to move the image to the central position.

7 more elements

Dependencies are inferred from the claim text.

Image null-balance system with multisector-cell direction sensing

Life of this patent

Image null-balance system with multisector-cell direction sensing

Life of this patent

Abstract

Claims33