Spatial modulation of light to determine object position

US9528925B2 · kind B2 · utility

Assignee

• Palo Alto Research Center Incorporated · US

Inventors

• Doron Kletter · San Mateo, US
• Joerg Martini · San Francisco, US
• Marshall W. Bern · Redwood City, US
• Noble M. Johnson · Menlo Park, US
• Peter Kiesel · Palo Alto, US
• Bowen Cheng · Atherton, US
• Michael I. Recht · Redwood City, US

Key dates

• Filing date: Feb 14, 2014
• Grant date: Dec 27, 2016
• Expiry date: Jan 5, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2021/8592
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Approaches for determining object position in a flow path are disclosed. A system includes a spatial filter having a length disposed along a longitudinal axis of the flow path and a width along a lateral axis of the flow path. The spatial filter has mask features configured to modulate light. Light emanating from objects moving along the flow path is detected. The detected light has a component along a detection axis that makes a non-zero angle with respect to the longitudinal and lateral axes. An electrical output signal that includes information about the trajectory depth of the object is generated in response to the detected light.