There are several types of non-invasive hair removal techniques currently on the market:

Laser:

The main principle of laser hair removal is selective photo thermolysis (SPTL), the matching of specific wavelengths of light and pulse duration to obtain the best effect on the target tissue with minimal impact on the surrounding tissue. The laser can selectively heat the dark target substance, melanin, which heats the basal stem cells in the hair follicle, causing hair growth, the follicle, without heating the rest of the skin, causing localized damage. Laser hair removal is a light band that can only use a single-color frequency.

IPL (WPL/HPL/eHPL):

This technology uses a high-power, hand-held, computer-controlled flashlight to deliver intense, visible, broad-spectrum light pulses, typically in the visible spectral range from 400 to 1200 nm. Often used with various filters to selectively filter lower wavelengths, especially UV light with damaging properties. The light produced by IPL has a spectral range that targets specific structures and chromophores (such as melanin in hair, or oxyhemoglobin in blood vessels) that are heated to the point of destruction and reabsorbed by the body. IPL shares some similarities with laser processing in that both use light to heat and destroy targets. But the difference is that lasers use a single wavelength (color) of light, lasers usually match only one chromophore, so can only satisfy a specific range of hairs (not available for non-dark colors), IPL uses a broad spectrum, and when used with filters, allowing it to be used in a variety of conditions (lighter shades available).

ELOS:

The IPL (spectral range in the range of 550~1200nm) is guided by RF targeting to target hair follicles, not skin melanin, and allows the light energy to be more concentrated and effectively targeted to hair tissue. ELOS technology can be used for hair removal for all skin colors and all hairs. The efficiency of ELOS light energy use is higher than that of simple IPL and laser. At the same time, the side effects of this technology on the skin are much smaller than that of IPL.