Method and device for monitoring movement of mirrors in a MEMS device
US8553308B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 2010 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Dec 2, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B26/0841
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for monitoring movement of at least one moving mirror in a MEMS device comprising one or more moving mirrors, and wherein the monitoring is based upon capacitance changes over time in the MEMS device. The method comprises the steps of: if the at least one moving mirror is an in-plain mirror, then: a. providing DC voltage to the MEMS device in addition to a driving voltage required for the movement of that at least one moving mirror; b. measuring current proportional to capacitance changes associated with the movement of the at least one moving mirror; and c. monitoring the movement of the at least one moving mirror based on the measured current. If the at least one moving mirror is a staggered mirror, then: d. measuring a current associated with the movement of the at least one moving mirror; e. identifying a plurality of ripples associated with capacitance changes in the MEMS device over time, in the measured current; and f. monitoring the movement of the at least one moving mirror based on the identified plurality of ripples.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.