Patent ID: 7336368
Filing Date: 2008-02-26
Classification: G01P,G06F

Abstract:
1. An optical detector for measuring a movement of an object in a space on a measurement axis, comprising: a light source, comprising a resonance chamber, the light source emitting a laser beam toward the object, the laser beam contacting the object and generating a first scattering beam and a reflection beam, wherein a part of the first scattering beam enters the resonance chamber; a reflective portion, reflecting the reflection beam toward the object, the reflection beam re-contacting the object and generating a second scattering beam and a sub-reflection beam, wherein a part of the second scattering beam and the sub-reflection beam enter the resonance chamber; a detection unit, measuring an optical-electrical variation in the resonance chamber to generate an electric signal; and a converting unit, converting the electric signal to a movement on the measurement axis in the space, wherein the first scattering beam, the second scattering beam and the sub-reflection beam are Doppler frequency shifted, and the optical-electrical variation is generated via a self-mixing of the first scattering beam and the second scattering beam.