Japan's Shimadzu Corp has developed a blue direct diode laser (DDL), providing what is claimed to be industry-leading brightness levels. The 10W-type laser is being exhibited at InterOpto 2013 at Pacifico Yokohama, Japan (16-18 October).
The global market for lasers for material processing applications was $2.6bn in 2010 and is expected to surge to $5.7bn by 2020, according to Optech Consulting's 'Fiber Laser Report 2011'. With machining lasers, in addition to conventional carbon dioxide lasers, diode-pumped solid-state lasers and fiber lasers (which use semiconductor lasers as their pumping sources) are increasingly becoming commonplace, says Shimadzu. Now, direct diode lasers (which use such semiconductor lasers directly for laser machining) have become a focus of attention as the next generation of laser machining light sources, because they are compact, feature high-efficiency electro-optic conversion, and can be mass-produced at low cost.
In this context, the development of higher-output direct diode lasers using near-infrared light is in progress, says Shimadzu. The realization of high-output semiconductor lasers that work at short wavelengths in the visible region (where the rate of absorption by metals is high) and that provide high brightness levels (from which high beam intensities can be obtained) will accommodate diversification of machining materials and enable deployment for microfabrication, where demand is increasing with the miniaturization of smartphones and other electronic devices, notes Shimadzu. The transition from carbon dioxide lasers and solid-state lasers to DDLs is hence expected to accelerate, with the commercial market expanding to about $0.5bn by 2020, according to Optech Consulting's 'Fiber Laser Report 2011'.
Shimadzu says that it has achieved a 16-fold increase in brightness over conventional levels for fiber-coupled blue semiconductor lasers, which feature high rates of absorption by metals. This has been achieved by utilizing newly developed optical multiplexing technology in addition to high-durability coating technology and techniques for precision assembly of optical equipment, cultivated to date based on gallium nitride (GaN) semiconductor lasers used in Blu-ray Discs and projectors. Shimadzu has hence developed what is reckoned to be the world's first blue direct diode laser that features a microscopic spot size and can be applied to microfabrication.
The blue direct diode laser features a fiber-coupling design that enables flexible laser beam delivery with high efficiency, even for kiloWatt-class output. Power consumption is about half that of solid-state green lasers, expanding the possibilities for laser machining instruments and processing instruments equipped with direct diode lasers.
Shimadzu says that it has been focusing on establishing a light source industry for the next generation of advanced laser machining. In September 2012 it released the BEAM IMPACT series of external resonator-type short-pulsed semiconductor lasers, a seed light source for fiber lasers. Furthermore, this April, it released a high-output laser mirror and laser window, and is subsequently targeting commercialization.
First, a 10W model will be released in January. Subsequently, 50W- and 100W-type lasers and spatial output types will be developed in order to enhance the product line, concludes Shimadzu.
