This article introduces the wavelengths, characteristics and dermatology applications of YAG lasers.

Q-switched 1064nm wavelength laser:
Treatment of nevus of Ota, freckles, traumatic hyperpigmentation, and removal of black and blue pigmented lesions such as tattoos, eyebrow tattoos, and eyeliner.

Q-switched 532nm wavelength laser:
Treatment of port wine stains, superficial coffee spots, removal of tattoos, eyebrow tattoos, eyeliner and other red and brown pigmented lesions.

The Q-switched dual-wavelength YAG laser therapy instrument adopts electro-optical Q-switching mode, and the pulse width is only 6ns. The single-pulse energy of 1064nm laser is up to 1200mj, and the laser energy is instantly emitted to efficiently destroy the chromophore of the diseased tissue.
That is, photoblasting: the high energy accumulated by the laser is emitted instantaneously, and the 1064&532nm wavelength laser acts on the target tissue in a very short time (6ns), and the corresponding chromophore absorbs the light energy and is heated and rapidly expanded and exploded instantly. After the base is fragmented, it is excreted from the epidermis, and a part of the chromophore (in the tissue below the epidermis) is fragmented into small particles that can be phagocytosed by macrophages. After being digested by macrophages, the chromophore is finally excreted through the lymphatic circulation. It gradually decreases until it disappears, and the surrounding normal tissues do not absorb or rarely absorb the laser light of 1064&532nm wavelength, so there is almost no damage (almost no clinical side effects), and there is no need to rest after surgery. Because of its single-pulse energy that is truly continuously adjustable, the electro-optical Q-switched laser can obtain any energy density (with the spot area unchanged) for clinical use.

YAG laser therapy instruments are widely used in hospitals, disease prevention and control centers and other health care institutions. There are many manufacturers of YAG laser therapy instruments, which are widely used, and the differences between various products are also relatively large.