11 Mar 2003
The pick of this week's patent applications including a method to improve the performance of Q-switched lasers.
• Title: Supression of mode-beating noise in a Q-switched pulsed laser using novel Q-switch device and applications
Applicant: Luxonics, Canada
International application number: WO 03/019739
A method to reduce the mode-beating noise of a Q-switched laser is detailed in patent application WO 03/019739. The authors say their technique uses an active, electro-optic or acousto-optic Q-switch in combination with a saturable absorber. "This offers larger modulation loss than otherwise possible with the active modulator alone and allows for higher gain build-up energy extraction efficiency," say the authors. The inventors claim that their method will result in cost-effective Q-switched lasers that can operate in both single-longitudinal and single-transverse mode.
• Title: System and method for notification of hazardous road conditions
Applicant: QWIP Technologies, Canada
International application number: WO 03/019494
Patent application WO 03/0194949 describes a system that warns drivers when hazardous road conditions are ahead. To detect hazards, the system uses an infrared detector mounted above the road. The detector is coupled to signal processing unit that recognises hazards such as ice, rain, animals and stationary vehicles. This information can then be passed to a roadside warning sign, alerting drivers approaching the hazard.
• Title: Apparatus and a method for pulse detection and characterization
Applicant: Raytheon Company, US
International application number: WO 03/019123
US-based Raytheon is trying to patent a pulse detection and characterization technique based on a Bragg cell. According to the patent, a detector receives an input signal (a collimated beam) that drives a Bragg cell. The Bragg cell then spatially modulates the beam and a series of lenses then image the output of the Bragg cell onto an opaque plate and a sensor. The sensor then detects and characterizes the pulses in the input signal.
Jacqueline Hewett is news reporter on Optics.org and Opto & Laser Europe magazine.