04 Nov 2003
The pick of this week’s patent applications including a system that tracks the position of a laser beam during eye surgery.
• Title: Beam position monitoring for laser eye surgery
Applicant: VISX, US
International application number: WO 03/090244
VISX of the US is trying to patent a system that monitors the movement of a laser beam across the eye during surgery. The idea involves directing two laser beams through a scanning mechanism. The first beam ablates the eye while the second beam is aimed at a sensor. As a laser surgery system moves the first beam across the eye, the scanning mechanism moves the second beam over the sensor. The sensor plots the movement of the first beam across the eye.
• Title: Gas-discharge lamp with a colour-compensating filter
Applicant: Philips Intellectual Property & Standards GmbH, Germany
International application number: WO 03/090250
The light emitted by car headlamps could soon lose its yellow tinge, thanks to the invention being patented in application WO 03/090250. The gas-discharge lamps that are typically used in car headlamps are made from a vessel containing a metal halide. According to the authors, the yellow tinge comes from the presence of metal halide salts that are not in the gaseous state when the lamp is on. They say that coating the outer envelope of the lamp with a compensating filter improves the color of the light.
• Title: Method and apparatus for laser vibrometry
Applicant: BAE Systems, UK
International application number: WO 03/089955
BAE Systems has come up with a laser-based system that accurately identifies remote targets. The system shines a laser on a target. Surface vibrations on the target modulate the phase of the scattered light. Optical receivers gather the scattered light and demodulate the signal. The scattered light also contains laser speckle, which is generated when radiation is scattered by a rough surfaces. “This speckle can generate errors in the demodulated signal, which in turn can cause identification errors,” say the authors. To overcome this, the inventors have come up with apparatus that they say is substantially unaffected by laser speckle.