Patent highlights

09 Sep 2003

The pick of this week’s patent applications including an optical system that can recognise constellations in the night sky.

•  Title: Pattern recognition system
Applicant: The University of Sussex, UK
International application number: WO 03/073366
Can’t tell the constellations Cassiopeia from Cancer or Libra from Leo in the night sky? If so, then the star pattern recognition system detailed in patent application WO 03/073366 could be one to watch out for. The device uses an array of independently tiltable mirrors. “Each mirror reflects the image of a different star in the pattern onto a common point on a detector, providing a detectable output intensity peak that indicates the presence of the star pattern in the field of view,” say the inventors.

•  Title: Method for preparing light emitting diodes
Applicant: Cambridge Display Technology Limited, UK
International application number: WO 03/073526
Cambridge Display Technology, the UK pioneer of light-emitting polymer technology, is patenting a method for fabricating high-efficiency light-emitting devices using solution processing. The technique involves depositing a layer of a porous low refractive index material, such as an aerogel, between the device’s light emitting layer and the substrate. The porous layer is then thermally patterned.

•  Title: Apparatus and method for detecting fecal and ingesta contamination on hands using an illumination device
Applicant: Emerge Interactive, Inc, US
International application number: WO 03/073081
Patent application WO 03/073081 describes a system that can detect fecal contaminants on a worker’s hands or utensils. The instrument uses a diffuse light source to excite red fluorescence between 660 and 680 nm from the contaminants. A detector monitors the emitted wavelengths and flags up the presence of any emissions within the critical 20nm waveband. The authors say the patent also details, “steps to identify the source of any contamination and to modify any practices so that the spread of contamination may be reduced.”

•  Title: Laser modulation and Q-switching using an inverse Fabry-Perot filter
Applicant: Coherent, Inc, US
International application number: WO 03/073568
Coherent of the US is trying to patent a modulation device that can be used as a Q-switch for a laser resonator. The device, which sits outside the laser cavity, comprises two wire-grids and is positioned to reflect and transmit radiation from the laser. “The reflected and transmitted radiation is modulated by varying the spacing between the wire-grid polarizers,” say the authors. Varying the device’s reflectivity from below to above that required for lasing initiates the Q-switching. They add that device may also be used as an end- or fold-mirror.

Author
Jacqueline Hewett is news reporter on Optics.org and Opto & Laser Europe magazine.