(1) Laser cutting processing analysis of directional illuminating

Ordinary light sources are illuminated in all directions. In order to let the emitted light propagate in one direction, it is necessary to install a certain concentrating device for the light source. For example, the headlights and the searchlights of the automobile are all equipped with a concentrating mirror, so that the radiant light is collected and emitted in one direction. The laser emitted by the laser is naturally emitted in one direction, and the divergence of the beam is extremely small, about 0.001 radians, nearly parallel. In 1962, the first time humans used lasers to illuminate the moon. The distance from the Earth to the moon was about 380,000 kilometers, but the laser spot on the moon's surface was less than two kilometers. If the concentrating effect is very good, the seemingly parallel searchlight column will be directed to the moon, and the entire moon will be covered according to the spot diameter.

(B) laser cutting processing analysis of extremely high brightness

Before the invention of the laser, the high-voltage pulsed xenon lamp in the artificial light source had the highest brightness, which was comparable to the brightness of the sun, and the laser brightness of the ruby ​​laser could exceed several billion times of the xenon lamp. Because the brightness of the laser is extremely high, it is possible to illuminate objects at a distance. The beam emitted by the ruby ​​laser produces an illuminance of approximately 0.02 lux (unit of illuminance) on the moon, with a bright red color and a visible laser spot. If the most powerful searchlight is used to illuminate the moon, the illuminance produced is only about one trillion lux, which is invisible to the human eye. The main reason for the extremely high laser brightness is directional illumination. A large number of photons are concentrated in a very small space, and the energy density is naturally extremely high. The ratio of the brightness of the laser to the sunlight is millions of, and it is created by humans. The color of the laser's color laser depends on the wavelength of the laser, and the wavelength depends on the active material that emits the laser, the material that is stimulated to produce the laser. Stimulating ruby ​​produces a deep rose laser beam that is used in the medical field, such as for the treatment of skin diseases and surgery. It is recognized that argon, one of the most expensive gases, produces a blue-green laser beam, which has many uses, such as laser printing, and is also indispensable in microscopic ophthalmic surgery. The laser produced by the semiconductor emits infrared light, so our eyes are invisible, but its energy just "interprets" the laser disc and can be used for fiber-optic communication. Laser separation technology Laser separation technology mainly refers to laser cutting technology and laser drilling technology. The laser separation technology focuses energy into a small space, and can obtain an extremely high irradiation power density of 105 to 1015 W/cm2. This high-density energy is used for non-contact, high-speed, high-precision processing methods. At such high optical power density illumination, laser cutting and perforation can be achieved for almost any material. Laser cutting technology is a new cutting method that can get rid of traditional mechanical cutting and heat treatment cutting. It has higher cutting precision, lower roughness, more flexible cutting method and higher production efficiency. As one of the methods for processing pores on solid materials, laser drilling has become a processing technology with specific applications, mainly used in the aerospace, aerospace and microelectronics industries.

(C) laser cutting processing color is extremely pure

The color of light is determined by the wavelength (or frequency) of the light. A certain wavelength corresponds to a certain color. The wavelength distribution of sunlight is between 0.76 micrometers and 0.4 micrometers, and the corresponding colors range from red to purple in 7 colors, so the sunlight cannot be monochromatic. A light source that emits a single color of light is called a monochromatic light source, and it emits a single wavelength of light. For example, xenon lamps, xenon lamps, xenon lamps, hydrogen lamps, etc. are all monochromatic light sources, laser cutting processing, only emitting light of a certain color. Although the wavelength of light waves of a monochromatic light source is single, there is still a certain range of distribution. For example, a xenon lamp emits only red light, and its monochromaticity is very good. It is known as the crown of monochromaticity. The wavelength distribution is still 0.00001 nm. Therefore, the red light emitted by the xenon lamp contains dozens of red colors if it is carefully identified. . It can be seen that the narrower the wavelength distribution interval of the optical radiation, the better the monochromaticity. The light output by the laser has a very narrow wavelength distribution, so the color is extremely pure. Taking a neon laser that outputs red light as an example, the wavelength distribution of the light can be as narrow as 2×10^-9 nm, which is two tenths of the wavelength distribution of the red light emitted by the xenon lamp. It can be seen that the monochromaticity of the laser far exceeds that of any monochromatic light source.

(4) The energy density of laser cutting processing is extremely high

The energy of a photon is calculated using E=hv, where h is the Planck constant and v is the frequency. It can be seen that the higher the frequency, the higher the energy. The laser frequency range is 3.846*10^(14)Hz to 7.89510(14)Hz. The electromagnetic spectrum can be roughly divided into: (1) radio waves - wavelengths from several kilometers to 0.3 meters, general television and radio broadcast bands It is to use such waves; (2) microwaves - wavelengths from 0.3 meters to 10^-3 meters, these waves are used in radar or other communication systems; (3) infrared - wavelengths from 10^-3 meters to 7.8×10 ^-7 meters; (4) Visible light - this is a very narrow band that people can sense. The wavelength is from 780 to 380 nm. Light is an electromagnetic wave emitted when an electron's motion state changes within an atom or molecule. Because it is the part of the electromagnetic wave that we can directly feel and detect it; (5) Ultraviolet light - the wavelength is from 3 × 10 ^ -7 meters to 6 × 10 ^ - 10 meters. These waves are caused by similar causes of light waves and are often emitted during discharge. Because its energy is equivalent to the amount of energy involved in general chemical reactions, the chemical effect of ultraviolet light is the strongest; (6) Roentgen ray - this part of the electromagnetic spectrum, wavelength from 2 × 10 ^ -9 meters to 6 × 10 ^ -12 meters. X-rays (X-rays) are emitted when the inner electrons of an electric atom jump from one energy state to another or when electrons decelerate within the nuclear field; (7) gamma rays are wavelengths from 10^- 10 to 10^-14 meters of electromagnetic waves. This invisible electromagnetic wave is emitted from the nucleus, which is often accompanied by radioactive or nuclear reactions. Gamma rays have a strong penetrating power and are highly destructive to living things. From this point of view, the laser energy is not very large, but its energy density is very large (because its scope of action is small, generally only one point), a large amount of energy is collected in a short time, and it can be used as a weapon. Understood.