03 Sep 2004
The pick of this week's patent applications including a method for stabilizing high-power diode lasers.
• Title: Laser source with high relative feedback and method for making such a laser source
Applicant: Bookham Technology plc, UK
International application number: WO 2004/073124
Bookham Technology of the UK is trying to patent a way to stabilize high-power diode lasers without resorting to active temperature control. The idea relies on an external reflector made from a fiber Bragg grating. "The reflector has an optimized and broadened reflectivity bandwidth with the advantage of achieving a stable output power within the locking range of the laser," say the inventors. They add that the idea could be useful for stablizing 980 nm diodes, which are used in optical communications to pump erbium-doped fiber amplifiers.
• Title: multi-wavelength mode-locked laser source
Applicant: Universite Laval, Canada
International application number: WO 2004/000189
A mode-locked multi-wavelength laser is discussed in patent application WO 2004/000189. The inventors believe their source could find applications in telecommunications, sensing and spectroscopy. The cavity contains an amplitude modulator, a frequency shifter, a spectral filter and a homogenous gain medium. The applicants say this combination allows multiple wavelengths to be generated at high repetition rates. They add that the cavity can be pumped by both electrical and optical sources.
• Title: Surgical needle with laser target
Applicant: Reinhardt Thyzel, Switzerland
International application number: WO 2004/071319
A Swiss inventor has come up with a device which he believes could be useful for treating cataracts. The so called "surgical needle" works by firing laser pulses down the needle at a metal target close to the distal end of the device. This generates shockwaves that shatter cataract tissue. The needle also contains an aspirating fluid which essentially sucks pieces of broken cataract tissue away from the eye. According to Thyzel, this ensures that stray fragments do not obstruct the surgery.
• Title: Personal solar adviser
Applicant: Alexander Smyk, US
International application number: WO 2004/072594
Are you worried about staying out in the Sun too long and damaging your skin? If so, then the personal solar adviser described in patent application WO 2004/072594 could be the gadget for you. The invention contains a system which monitors a person's exposure to UV radiation and an indicator which flags up when the UV radiation dose has reached a set level. Alexander Smyk, the inventor of the solar advisor, says the device takes into account factors such as skin type, whether the skin in untanned or already tanned and the SPF of sunscreen that is being worn by the user.