How much do you know about lasers

What is a laser?

"Laser" stands for "Light Amplification by Stimulated Emission of Radiation". Laser  emits light coherently which allows a narrow spectrum laser beam and a focused light spot on a targeted surface.

What are lasers used for?

Lasers are greatly applicable in usual presentation work in astronomy research, star pointing, pet toys and laser display entertainment, industrial laser alignment system, laser surgery and laser therapy in physical treatment of muscle pain and relaxing, laser hair removal. Lasers are commonly used in consumer devices such as CD and DVD players, laser printers, bar code scanners, laser alignment, and laser pointers etc. Lasers are also widely applied in many important scientific researches.

What does "mW" stand for?

"mW" stands for mill watt. It is the output power of a laser. "mW" means one thousand of a watt. The output power will determine how powerful the laser will be. A low powered laser pointer among 1mW-50mW is basically used for presentation; A middle powered handheld laser is applicable for military targeting, burning and thermal experiments; A high powered laser is mostly applicable in medical care, military, industry and surveillance etc.

What does wavelength mean?

Wavelength is always described in nanometer, and determines the color of the laser. The usual available wavelengths are divided into three parts: Ultraviolet light: 100-400nm; Visible light: 400-750nm; Infrared Light: 750nm-1mm, 785 nm, 808nm, 830 nm, 980 nm, 1064 nm.

Human eyes are capable to see radiation from visible light (400-750nm). The visible laser color from shortest to longest wavelengths are violet, blue, green, yellow and red. Ultraviolet wavelength is shorter than visible light, emits invisible light to human eyes. Infrared radiation has longer wavelength than visible red light, project invisible light to human eyes.

What is output power?

The output power is related to the produced power of the laser beam, which is usually stated in milliwatt (mW). The milliwatt is a unit of power, which is one one-thousand of a watt. Higher power lasers are always more powerful than lower power lasers.