Single fluoride-fiber laser produces white laser light

Sumita Optical Glass claims to have achieved the first continuous-wave white-laser oscillation with a new single fluoride glass fiber by combining three primary colors (red, green, and blue). The white-light laser resulted from the combination of 522 and 635 nm laser energy, simultaneously excited by guiding 440 nm blue diode-laser light into a fluoride-glass fiber, plus residual light from the blue diode laser. The fiber consists of aluminum fluoride glass doped with praseodymium, which emits green and red fluorescence upon absorbing light from the blue diode laser. Some commercial fluoride-glass fibers are available, but most are made of a combination of zircon-fluoride glasses, which is less practical.

To date, white laser light has typically been created by combining three primary colors generated separately in some way, for example, in a gas laser or by guiding IR laser energy into a nonlinear crystal. However, those methods suffer from issues such as conversion inefficiency, which increases energy consumption, requires a larger laser oscillator, and high cost. Because Sumita’s white-light laser is configured with a single fluoride-glass fiber and 440 nm diode laser it results in better conversion efficiency, energy consumption, size, cost, and performance. Contact Masatoshi Sumita at [email protected].