03 Jun 2004
The pick of this week’s patent applications including a diode-pumped thin slab laser that emits in excess of 150 W.
• Title: Diode-pumped solid-state thin slab laser
Applicant: Spectra-Physics, US
International application number: WO 2004/045034
Patent application WO 2004/045034 details an edge-pumped solid-state thin slab laser. The inventors claim the laser is scalable to powers in excess of 150 W for both multimode or near single transverse mode operation. The thickness of the slab is crucial. It has to be thin enough to minimize thermal effects while being thick enough to allow efficient direct coupling of the pump light from high power diode laser stacks. The slab is cooled conductively by placing it in contact with metal blocks that have a high thermal conductivity.
• Title: Optical lenses
Applicant: Agilent Technologies, US
International application number: WO 2004/044628
Coupling laser light into a fiber could become a lot easier thanks to a lens which is being patented by Agilent Technologies. The authors say that that lens prevents optical feedback into the laser and can be economically manufactured in high volume as either single components or in arrays. One surface of the lens is said to combine a conic, a spiral and a cone component. “The conic component can be one of hyperbolic, parabolic or spherical in shape,” say the authors. The other surface is a convex hyperbolic. The applicants say the lens can be produced in a mold.
• Title: Multi-spectral line Raman laser
Applicant: Corning, US
International application number: WO 2004/045033
Corning of the US is trying to patent a Raman laser capable of emitting several wavelengths simultaneously. The applicants claim that the output power at each wavelength can be adjusted. The laser cavity contains a strain-based device, which controls the relative power emitted at each wavelength. The application details several cavity designs. In one instance a linear length of gain fiber acts as a cavity and fiber Bragg gratings are used as reflectors to control the emitted wavelength.