TeraDiode ships multi kilowatt diode laser
Beam quality suitable for high throughput steel cutting
TeraDiode, a spinout from MIT, has announced shipment of its first 4kW high brightness TeraBlade diode laser. The 970nm laser has a beam-parameter-product (BPP) of 4mm-mrad, making it suitable for high throughput cutting of steel over the range of thicknesses cut by laser cutters in job shops around the world, says the company. TeraDiode has already demonstrated diode lasers capable of cutting 12.7mm mild steel with cut quality and speed comparable to disk and fibre lasers.
Parviz Tayebati, CEO of TeraDiode, said: "In the short time since our first industrial shipments, we doubled the power of our laser modules from 600W to 1.2kW. These modules, which we use in our multi-kilowatt systems, reduce our production cost to just below that of the incumbents who have needed years of shipping in high volume to reach these levels. From here, increasing our production will accelerate further improvements to widen the gap in efficiency, reliability and cost of ownership over the incumbents."
Diode lasers - used in laser pointers, barcode scanners, DVD players, and other low-power applications - are amongst the most efficient, compact, and low-cost lasers available. Attempts have been made over the years to increase their brightness for industrial applications, such as welding and cutting metal, but boosting power usually meant decreasing beam quality, or focus.
TeraDiode has made these lasers powerful enough to cut steel using a combination of semiconductor diode laser array chips and a power-scaling technique, called wavelength beam combining (WBC), developed at MIT. WBC manipulates individual diode laser beams into a single output ray to boost the power of a diode laser, while preserving a very focused beam. TeraDiode believes that direct-diode lasers using this technology will, in time, replace fibre, disk and other lasers for the most demanding material processing applications.
WBC can be thought of as the spatial and directional superposition of many independent diode laser external cavities, says the company. The angle-to-wavelength conversion property of a diffraction grating is used to provide feedback to each emitter in an array, via a series of lenses, at different wavelengths. The laser resonator is formed between the HR coated back facet of the emitter and the output coupler. WBC allows for brightness scaling of an emitter array because all of the laser elements are spatially overlapped at the output coupler, maintaining the output beam quality of a single element while scaling the output power by the number of elements in the array.
