Laser is a great invention in the 20th century, and it is called the fastest knife, the most accurate ruler and the brightest light. Laser (light amplification by stimulated emission of radiation), which means stimulated radiation light amplification, describes the principle of laser generation.

In the laser diode market, red and blue semiconductor diodes are mature and widely used in display devices. Although green semiconductor laser technology has made some progress recently.

Medical science is the earliest, most extensive and most active frontier subject in which laser technology is applied. There are dozens of varieties of laser medical equipment used clinically.

Visible light refers to the electromagnetic wave that can cause vision, and it is the part of the electromagnetic spectrum that can be perceived by human eyes.Invisible light is a general concept.

Jumpers are cables directly connected to desktop computers or equipment to facilitate the connection and management of equipment. Jumpers have a thick protective layer and are often used between terminal boxes and optical terminals. Only one end of the tail fiber has a connector, and the other end is an optical fiber connector.

Infrared absorption spectrum is also a kind of molecular absorption spectrum. when the sample is irradiated by infrared light with continuously changing frequency, the molecules absorb some frequencies of radiation, and its vibration or rotation motion causes the net change of dipole moment, resulting in the transition of molecular vibration and rotation energy level from the ground state to the excited state, which weakens the transmitted light intensity corresponding to these absorption regions.

Infrared is the abbreviation of infrared ray. It is an electromagnetic wave with a wavelength of about 3.3 μ m. The laser amplifies the generated radiation by stimulated light emitted at 1.65um.

Laser modulation is the process of using laser as carrier wave for modulation. Laser has excellent temporal coherence and spatial coherence. It is similar to radio wave, easy to modulate, and the frequency of light wave is very high, and the capacity of transmitting information is very large.

DPSS laser is the diode pump solid state laser, excitation source for the semiconductor laser diode (module), laser module stimulated medium for special optical crystal solid materials, general for the rare earth doped crystals or other metal ions of YAG, YVO4 and GGG, is infrared wavelength range, generally is a common single wavelength.

The red laser pointer is easier to make, because there is a laser diode that generates this wavelength, so its structure is the simplest, basically just a diode powered by a battery. Wavelength is about 600 nanometers, there are mature technology, there are mature semiconductor process materials.