A<unk><unk>  laser in 2021 Several wavelengths of laser energy have been used for<unk><unk> , from visible light to near-infrared radiation. These lasers are characterized by their wavelength, measured in nanometers (nm): Laser Used Wavelength (nm) Light Source Type of Skin used on Argon 488 nm or 514.5 nm Turquoise/Cyan or Green No longer used Ruby 694.3 nm Deep red Pale Alexandrite 755 nm Near-infrared All skin types Pulsed diode array 810 nm Near-infrared Pale to medium Nd:YAG 1064 nm Infrared Darker complexion Intense pulsed light (IPL is not a laser) 650 nm Not a laser Pale to medium Pulse width (or duration) is one of the most important considerations. The length of the heating pulse relates directly to the damage achieved in the follicle. When attempting to destroy<unk>  follicles the main target is the germ cells which live on the surface of the<unk>  shaft. Light energy is absorbed by the melanin within the<unk>  and heat is generated. The heat then conducts out towards the germ cells. As long as a sufficient temperature is maintained for the required time then these cells will be successfully destroyed. This is absolutely critical – attaining the required temperature is not sufficient unless it is kept at that temperature for the corresponding time. This is determined by the Arrhenius Rate Equation. To achieve these conditions the laser/IPL system must be able to generate the required power output. The main reason why<unk><unk>  fails is simply because the equipment cannot generate the desired temperature for the correct time. Spot size, or the width of the laser beam, directly affects the depth of penetration of the light energy due to scattering effects in the dermal layer. Larger beam diameters or those devices that has a linear scanning results in deeper deposition of energy and hence can induce higher temperatures in deeper follicles.<unk><unk>  lasers have a spot size about the size of a fingertip (3–18mm). Fluence or energy density is another important consideration. Fluence is measured in joules per square centimeter (J/cm²). It's important to get treated at high enough settings to heat up the follicles enough to disable them from producing<unk> . Epidermal cooling has been determined to allow higher fluences and reduce pain and side effects, especially in darker skin. Three types of cooling have been developed: *Contact cooling: through a window cooled by circulating water or other internal coolant. This type of cooling is by far the most efficient method of keeping the epidermis protected since it provides a constant heat sink at the skin surface. Sapphire windows are much more conductive than quartz. *Cryogen spray: sprayed directly onto the skin immediately before and/or after the laser pulse *Air cooling: forced cold air at -34 °C In essence, the important output parameter when treating<unk>  (and other skin conditions) is power density – this is a combination of energy, spot diameter and pulse duration. These three parameters determine what actually happens when the light energy is absorbed by the tissue chromophore be it melanin, hemoglobin or water, with the amount of tissue damaged being determined by the temperature/time combination.
Laser hair removal
Ultraviolet light therapy
Low-level laser therapy
Laser coagulation
GreenLight Laser Therapy
Laser surgery
Plesiotherapy
Climatotherapy