22 Jan 2004
The pick of this week’s patent applications including an optical device that monitors the tread depth of car tyres.
• Title: Tyre wear indicator
Applicant: Robert Bosch GmbH, Germany
International application number: WO 04/005052
German firm Robert Bosch has invented a device that monitors the level of wear in car tyres. According to the company, the tyre contains a light-emitting element which passes through both the tread and the wall of the tyre and illuminates the inner volume of the tyre. “A light ray detector is installed inside the inner volume of the tyre and can emit a wear-indicating signal in response to the light flux,” say the application’s authors.
• Title: Method for conducting financial transactions utilizing infrared data communications
Applicant: Visa International Service Association, US
International application number: WO 04/006484
Visa is trying to patent a way to conduct a transaction between two electronic devices over an infrared frequency. Crucially, a common encryption algorithm is stored on each device. The first device transmits a transaction request and an encryption key to the second device. The second device then responds by sending data which has been encrypted using both the common algorithm and the key. “The account to be utilized in the transaction is derived from the response data,” say the inventors.
• Title: A superluminescent diode
Applicant: Denselight Semiconductors PTE Ltd, Singapore
International application number: WO 04/005985
Patent application WO 04/005985 details a superluminescent diode (SLD) that contains a planar optical waveguide. The SLD also comprises two tapered trenches which extend from a facet and define a ridge in the waveguide. The combination of the tapered trenches and ridge guides light away from the facet where it is evanescently coupled to a surrounding broad area waveguide. The authors say this set up reduces the amount of light that is reflected back into the guided mode.
• Title: Laser tweezers and Raman spectroscopy systems and methods for the study of microscopic particles
Applicant: East Carolina University, US
International application number: WO 04/008121
Scientists in the US have applied to patent their combined optical tweezers and Raman spectroscopy system. The system uses a low-power beam to trap a microscopic particle. The laser’s power is then increased and excites Raman scattering signals from the trapped particle. A Raman spectrum can be produced from the detected Raman scattering signals.