Charge management of electrically isolated objects via modulated photoelectric charge transfer

US7751170B2 · kind B2 · utility

Assignee

• The Board of Trustees of the Leland Stanford Junior University · US

Inventors

• Ke Sun · Mercer Island, US
• Brett A. Allard · Mountain View, US
• Robert L. Byer · Stanford, US
• Saps Buchman · Palo Alto, US

Key dates

• Filing date: Jun 1, 2007
• Grant date: Jul 6, 2010
• Expiry date: Oct 16, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G01V7/04
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Charge transfer is provided to or from an electrically isolated test body by AC modulation of the photoelectric effect. More specifically, a reference body is disposed near the test body without physical contact between the reference and test bodies. Facing surfaces of the reference and test bodies are illuminated by optical radiation having a sufficiently short wavelength that charged particles are emitted from the reference and test bodies. An electrical bias is established between the reference body and the test body. Both the optical radiation and the electrical bias are modulated at the same frequency. A magnitude and direction of a charge transfer rate between the reference and test bodies is set by selecting a phase relation between the optical radiation and the electrical bias.