Patent ID: 6567174
Filing Date: 2003-05-20
Classification: G01P

Abstract:
A method for measuring acceleration, comprising the steps of:providing an accelerometer apparatus comprising a 90-degree prism formed of an optically transparent, stress-birefringent material, the prism having a first prism side and a second prism side adjacent to a right angle of the prism, and a prism hypotenuse side opposite to the right angle of the prism, a source of polarized light positioned to direct a polarized beam of light into the optically transparent, stress-birefringent material, the source of polarized light comprising a laser optical source producing a polarized beam directed normal to the prism hypotenuse side and toward an incident location of the first prism side, and a detector system positioned to detect an output beam from the optically transparent, stress-birefringent material, the detector system comprising a diffraction grating in contact with the first prism side at the incident location, an imaging detector positioned to receive a diffracted beam from the diffraction grating, an intensity detector positioned to receive a reflected beam that travels in a reflected beam path from the laser optical source, reflects from the incident location of the first prism side, reflects from the second prism side, and passes through the prism hypotenuse side, and a polarizer positioned along the reflected beam path between the prism hypotenuse side and the intensity detector; accelerating the accelerometer apparatus; and simultaneously determining the acceleration of the accelerometer apparatus from a measurement of stress-induced optical birefringence in the optically transparent, stress-birefringent material.