So, what is laser? Next, Vico.com will provide a detailed introduction.
Laser generation
Laser, also known as "laser," stands for "stimulated emission of light." In 1917, Einstein proposed the theory of stimulated emission, which states that a single photon causes an excited atom to emit the same photon. In 1960, Maiman, a researcher at Hughes Aircraft Laboratory in California, invented the world's first ruby laser. In 1961, China's first laser was developed at the Changchun Institute of Optics, Fine Mechanics and Physics, led by Wang Daheng. In 1965, Bell Labs invented the first YAG (solid-state) laser.
When particles in the atoms of certain substances are excited by light or electricity, they transition from lower energy levels to higher energy levels. When the number of high-energy level atoms exceeds the number of low-energy level atoms, and they transition back to lower energy levels, they emit light with identical phase, frequency, and direction. This light is called laser light. When irradiated by pump light, ground-state ions absorb light of a specific wavelength and transition to the E3 energy level. Subsequently, they rapidly transition to the E2 energy level through a non-radiative transition, where a large number of ions can accumulate. When the external pump is strong enough, population inversion occurs between the E2 and E1 energy levels, meaning that the number of ions in the E2 energy level is greater than that in the E1 energy level. After population inversion, each incoming photon with energy hν excites an atom in the E2 energy level to transition to the ground state, simultaneously releasing a photon with energy hν. The total energy of the photons continuously multiplies, thus realizing the stimulated emission amplification (gain) process.
What is a laser?
A laser is a device that generates laser light, mainly composed of a pump source, a gain medium, and a resonant cavity. The pump source is the excitation source of the laser, and the resonant cavity is the circuit between the pump source and the gain medium. The gain medium refers to the working material that amplifies the light. In operation, the gain medium absorbs the energy provided by the pump source, and the laser light is output through mode selection and oscillation in the resonant cavity.
Lasers are the core component of laser processing equipment and play a crucial role in the cost structure of such equipment. Lasers can be classified into many types according to their working medium, output wavelength, and output type.
Lasers can be classified according to their working material into solid-state lasers (ruby Al₂O₃, yttrium aluminum garnet lasers), liquid lasers (dye lasers), gas lasers (helium-neon lasers, argon ion lasers, etc.), semiconductor lasers, fiber lasers, and free-electron lasers. Based on their output wavelength, lasers can be classified into far-infrared lasers, mid-infrared lasers, near-infrared lasers, visible lasers, near-ultraviolet lasers, and vacuum ultraviolet lasers. According to their output type, lasers can be classified into continuous-wave lasers, quasi-continuous-wave lasers, short-pulse lasers, and ultrashort-pulse lasers.
Development and application of laser technology
Laser technology, as one of the advanced technologies in modern manufacturing, possesses advantages such as high precision, high efficiency, low energy consumption, and low cost that traditional processing methods lack. It offers greater flexibility in terms of the material, shape, size, and processing environment, effectively addressing technical challenges in processing and refining caused by different materials. With the continuous development of laser technology and laser micromachining applications, laser processing technology is replacing traditional machining in more fields. Laser precision micromachining, in particular, has gradually become a core processing technology in high-end manufacturing due to its higher precision, greater flexibility, smaller thermal effects, and wider applicability.
In terms of laser applications, laser technology can be widely used in cutting, welding, drilling, marking, engraving, measurement, diagnosis and other fields. my country's industrial upgrading is imminent, and the demand for laser technology in multiple fields such as micro-welding, precision measurement, biomedical diagnosis and chip manufacturing is constantly rising. Laser technology has entered a new process of rapid development.
From the perspective of the development of the laser industry, laser technology has been widely applied in fields such as consumer electronics, 3D printing, semiconductors, new energy, displays, biomedicine, and laser testing. Many domestic companies have the strength to compete with foreign companies, and their influence in the international laser industry is growing stronger.
In conclusion, lasers have already played a crucial and irreplaceable role in certain fields, and an increasing number of industries are beginning to value the application of laser technology. This has led domestic laser companies to continuously increase their investment in laser technology research and development, intensifying competition within the laser industry. For the development of my country's laser industry, this is undoubtedly a positive sign. Against this backdrop, we can more quickly narrow the gap with international counterparts, fill our technological gaps, and provide vital technological support for the development of science and technology in my country.
