White light laser is a key research and development object of scientists from various countries. It can not only expand new fields of laser application, but also the foundation of new technology. The research of non-linear crystal is an important part of the research and development of white light laser, but in the research and development process, people often ignore the laser characteristics that the output white light laser pointer should have, and the effect of “laser in, laser out” is not really achieved. By irradiating the non-linear crystal with the excitation laser, the white laser produced should have all the characteristics of the laser and be a real laser. The white light laser has lost many excellent characteristics of the laser, hindering the application and development of the white light laser.
Now that white light lasers have been used in some fields, there are many ways to generate white light lasers. How to correctly understand the white light lasers that have been born now? How to define white light laser in real sense? Can a real white laser be created?
A) The white laser has been applied in many fields because of its advantages that the traditional laser does not. White lasers are produced in various ways, and many scientists have always been interested in the research of white laser technology. As an artificial light source, the laser has always existed in the three primary colors of red, green and blue; because of its unique “three good and one high” (good monochromaticity, good coherence, good directionality and high brightness) characteristics, it has been widely used in many fields application.
Due to the limitation of the laser generated by the laser, the green laser pointer has good monochromatic characteristics, but this has also become a shortcoming of the laser in the application field; the laser cannot produce any wavelength of laser, nor can it produce super continuous and ultra wide band Laser. In the field of laser applications, people have different needs for the frequency (or wavelength) of the laser. At this time, we must rely on the help of nonlinear crystals. But lasers in many wave bands still cannot be created.
Currently, nonlinear crystals can only produce lasers with a limited range of wavelengths. Compared with the ultra-wide spectrum white light laser, the laser with narrow wavelength range can carry much less energy and information than the latter. Therefore, fully coherent, super-continuum, ultra-wideband, white laser covering the solar spectrum has become the key research object of scientists from various countries. The development of white laser will also bring revolutionary changes and subversion to the application field of laser.