The development and use of laser glass

In the early 1960s, the first ruby lasers with solid activating media appeared. Snitzer reported laser-doped Nd3 + -based silicate glass in 1961. In 1962, China also received neodymium silicate glass laser output. Glass and crystal constitute two categories of solid laser materials. Compared with the crystalline material, the excited ions in the glass in the stimulated emission section is smaller, but the storage capacity; glass matrix thermomechanical properties as crystals, mainly for pulse lasers and amplifiers to output a larger energy and power. Compared with the laser crystal, the glass as a laser activated ion matrix in the glass properties and manufacturing process has a series of advantages.

(1) Substrate glass is easy to change Select the different glass system can make a wide range of glass composition changes; can be added to different types and the number of activated ions, developed into different characteristics of the laser glass to meet the requirements of a variety of lasers.

(2) The structural defects of the disordered structure and the isotropic glass have little effect on the properties of the glass, and the coordination of the activated ions is stable, and the isotropic optical homogeneous medium can be obtained.

(3) easy to manufacture optical glass technology can be used to obtain a highly uniform material; easy to shape, can be made from glass fiber to meters of glass rods and plates; through precision annealing can achieve high refractive index uniformity and very low stress Birefringence; can improve the mechanical strength of the glass by surface treatment.

(4) can be mass-produced glass melting cycle is short, glass raw materials cheap, easy to achieve optical research and polishing.

Since the emergence of Nd3 + in the glass after the laser, the sixties and seventies of the 20th century, has been committed to explore a variety of in the glass

To achieve the laser output of the ion. Many rare earth ions are doped with glass to achieve laser output. One of the most valuable ions for the Nd3 + and Er3 +, later became the focus of research and development. On the other hand is to develop the practical application of laser glass. Until now, the real application of laser glass for neodymium laser glass and erbium laser glass, and mainly neodymium laser glass. In the last 40 years, including the activation of ions in the glass in the spectrum, light, nonlinear effects and other basic research; laser material performance measurement, detection technology and equipment to establish; laser glass product development and laser glass unique Manufacturing technology, these work are to Chin laser glass as the object.

Since 1961, Chin laser glass is mainly used for the construction of high energy and high power lasers. To the early 1000 joule-class high-energy lasers to the later TW-class, the recent 1014W high-power laser system. The earliest use of silicate neodymium laser glass, and later in high energy, short pulse under the glass damage, due to non-linear self-focusing optical effect, requiring a reduction in the glass's nonlinear refractive index 〃 2. In order to increase the gain of the laser, a laser glass with a large emission section is required. Phosphate laser glass has excellent properties in both respects. Since the 1980s, phosphate laser has gradually replaced silicate glass for the construction of high energy and high power laser systems. In order to obtain optical uniform glass and prevent contamination, laser glass is melted by molybdenum crucible. In the 1960s, there were different points of damage caused by strong laser under self-focusing filamentous failure. This damage is due to the temperature rise and gasification of the tiny metal platinum particles in the glass under strong lasers. In order to avoid the pollution of platinum on glass, laser glass to carry out all ceramic research. Due to the existence of poor optical uniformity of light, light absorption and other inherent shortcomings and stop further development. At the same time, the development of platinum crucible melting in the elimination of molybdenum metal particles. The technology represented by American Optical Corporation is an inert gas protection, and the technology for preventing redox deposition is still used by Kigre Corporation for the manufacture of silicate and phosphate laser glass. Another process for the oxidation method, the use of platinum in the phosphate glass in the large solubility of the glass in the platinum in the ionic state, to avoid the formation of metal molybdenum. The technology was organized by the American Lawrence Livermore National Laboratory, Schott and Hoya, respectively, in the late 1980s. China began in the early 90s of the 20th century, 90 years to complete the oxidation method "in addition to platinum" technology. Now China's high-power laser system of phosphate laser glass are used in this process manufacturing. In order to adapt to the US NIF (Laser Fusion Fusion National Ignition Program) and the French LMJ (Laser Megajoule) laser system in the laser glass physical properties, quality consistency and huge quantity requirements, investment by the US and French governments, Schott and Hoya from the 20th century, 90 years to carry out continuous melting of laser glass research. 2000 began to run, to May 2002, completed the NIF required more than 3000 pieces of laser Chin glass.

Erbium-doped glass in the 20th century, 60 years have been laser output, from the erbium ion absorption, spectral and stimulated emission properties, are not as laser light glass. Until the 20th century, 80 years before the development of laser glass products. The main driving force is that the laser wavelength of Er3 + in the glass is 1.54 ^ m, the laser power of the eye can be much greater than 1. 06 ^ m, which is used in the atmosphere through the window, mainly for ranging, Medical surgery, laser and other atmospheric radar.