Method and apparatus for micro-machined sensors using enhanced modulated integrative differential optical sensing
US7091715B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 14, 2001 |
| Grant date | Aug 15, 2006 |
| Priority date | — |
| Expiry date | May 16, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01P2015/0814
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Method and apparatus for sensing the displacements of micromachined devices and sensors. The method is referred to as the enhanced modulated integrative differential optical sensing (EMIDOS). The target micromachined proof-mass, for which displacements are measured, includes a grid of slits. The micromachined device is bonded to a CMOS chip containing a matching photodiodes array and their readout electronics. The grid is aligned with the photociiodes. An illumination source, such as an LED, is then mounted above the micromachined device. A model for the noise equivalent displacement (NED), including mechanical, electrical and optical domains, as well as all noise sources is derived. The model predicts that displacements below 10−3 [√{square root over ( )}Hz] can be measured. The design comprises innovative inertial sensors, an accelerometer and a rategyroscope employing the EMIDOS. Performance models for the noise equivalent acceleration (NEA) and noise equivalent rate (NER) are also derived. The models show that an accelerometer with a very low NEA can be realized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.