06 Aug 2003
The pick of this week’s patent applications including a fingerprint sensor and a security tag made from micro-optics.
• Title: Optical biometric sensor with planar waveguide
Applicant: QinetiQ, UK
International application number: WO 03/063065
A design for an optical fingerprint sensor is unveiled in patent application WO 03/063065. According to the authors, the invention relies on coupling light from a laser diode array into a planar waveguide. When ridges of skin from a finger or palm touch the surface of the waveguide, light is coupled out of the waveguide at the point of contact and received by a detector array. The developer QinetiQ says that the design is less complicated then competing approaches and is able to remove noise due to the build up of grease on the sensor.
• Title: Micro-optics for article identification
Applicant: Nanoventions, US
International application number: WO 03/061983
Nanoventions of Georgia, US, is patenting a method for identifying objects through the use of micro-optics. The firm says that rather than using holography it exploits a range of “distinctive optical effects” obtained from miniature systems containing micro-lenses, waveguides, gratings, filters and photonic crystal microstructures.
• Title: Integrated optical router
Applicant: University of California
International application number: WO 03/062879
Data packets in an optical network employing wavelength division multiplexing (WDM) may one day be routed by an optoelectronic circuit designed by scientists in the US. Researchers at the University of California have designed an optical router that fits on an indium phosphide substrate that is bonded to a thermo-electric cooler. The device uses fast electronics alongside arrayed waveguide gratings, wavelength converters, photodetectors and laser diodes to perform the routing.
Oliver Graydon is editor of Optics.org and Opto & Laser Europe magazine.