Capacitive charge based self-sensing and position observer for electrostatic MEMS mirrors

US11467394B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Richard SCHROEDTER · Doren, AT
• Han Woong Yoo · Wien, AT
• David Brunner · Dobersberg, AT
• Georg Schitter · Wien, AT
• Franz Michael Darrer · Graz, AT
• Marcus Hennecke · Ulm, DE

Key dates

• Filing date: Feb 28, 2020
• Grant date: Oct 11, 2022
• Expiry date: Apr 11, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B26/10
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An oscillator system includes an electrostatic oscillator structure configured to oscillate about an axis based on a deflection that varies over time; an actuator configured to drive the electrostatic oscillator structure about the axis, the actuator including a first capacitive element having a first capacitance dependent on the deflection and a second capacitive element having a second capacitance dependent on the deflection; a sensing circuit configured to receive a first displacement current from the first capacitive element and a second displacement current from the second capacitive element, to integrate the first displacement current to generate a first capacitive charge value, and to integrate the second displacement current to generate a second capacitive charge value; and a measurement circuit configured to receive the first and the second capacitive charge values and to measure the deflection of the electrostatic oscillator structure based on the first and the second capacitive charge values.