In real life, the most intuitive understanding of white light lasers is laser display technology and lighting technology. They all need to apply a laser pointer—white light laser that covers all wavelengths of the visible spectrum. In addition, according to the characteristics that laser photons can carry energy and information, white lasers have more advantages than monochromatic lasers with a narrow wavelength range, and can be used as an alternative light source for optical communications and high-power cutting.
In 2014, at the Nobel Awards Ceremony, Nakamura Shuji, the father of Blu-ray and Nobel Prize winner, said: “In the next 5-10 years, laser lighting will replace LED lighting.” For this reason, in December 2016, “Nakamura Shuji Laser “Lighting Lab” was established in Shenzhen. Shuji Nakamura, the founder of LED lighting, now wants to subvert the LED lighting empire he created.
As the next-generation display technology, laser display has also attracted the attention of the scientific and technological community and the business community. Compared with traditional display technology, laser display has leading advantages in terms of high brightness, sharpness, color gamut, color saturation, and service life, and has great industrialization prospects; many Chinese companies have set off laser TV fever, related products Already listed.
From the root point of view, the development and acquisition of white laser light source is the basic premise of white laser application. As early as 2004, the research team of Nanjing University combined dual-wavelength laser technology and optical superlattice frequency conversion technology to obtain the first 530mW white green laser pointer output. However, the acquisition scheme is complicated. The fundamental wave source is a dual-wavelength output laser, and the nonlinear crystal is an optical superlattice with a cascade structure. Red, green, and blue three are obtained by frequency doubling and triple frequency doubling of two fundamental wave infrared spectral lines. Primary color light, and adjust the power ratio between the three color lights by adjusting the crystal temperature and other parameters to obtain white light laser output. But this white light laser is not only difficult to obtain, but its performance is extremely unstable.
Coincidentally, in 2011, Sandia National Laboratory in the United States used four separate large-scale lasers to produce high-quality white laser light. But these discrete large lasers are not suitable for practical applications such as lighting or display equipment. The team has also realized the tuned output of visible laser by studying semiconductor materials, and can recombine into white laser by adjusting the power ratio of the three primary colors of red, green and blue. In 2015, they announced that the world’s first white laser was born in the United States.
The developer said: “The laser has a high monochromaticity. Compared with ordinary light sources, all the optical radiation emitted by the laser is concentrated in a narrow frequency range. Therefore, according to common sense, white lasers are impossible to emit. However, by adjusting the intensity ratio of the three primary colors of red, green, and blue lasers, the three primary colors meet to produce a white laser, which makes the impossible possible. It can be said that the white laser is the composite light of the entire visible spectrum. ” The white laser produced by the world’s first white laser was born in the United States. It is a compound laser based on three primary lasers.
At present, there are various methods for generating white lasers, but most of the root causes are inseparable from the traditional lasers—red, green, and blue primary lasers. In addition to the above methods, photonic crystal fiber white light lasers can also produce high-power, broadband, super-continuum white light lasers. The white light laser it produces is mainly used in many fields such as photocurrent microscopy, nanophotonics, fluorescence spectroscopy and imaging, super-resolution imaging, optical coherence tomography and so on.