Final answer:
The photoepilation hair-reduction uses Intense Pulsed Light (IPL) or laser hair removal methods that apply intense light of various wavelengths and very pure wavelength electromagnetic radiation to target and damage the hair follicles to inhibit growth.
Step-by-step explanation:
The photoepilation hair-reduction method using flashes of light refers to procedures like Intense Pulsed Light (IPL) and laser hair removal. These methods employ intense light of varied wavelengths to target and reduce hair growth. During these procedures, a broad spectrum of light is filtered to allow various wavelengths to be used in treating different skin and hair types. The light energy is absorbed by the pigment (melanin) in the hair, which is then converted to heat. This heat damages the hair follicle and inhibits future hair growth without affecting the surrounding tissue.
Lasers provide a very pure wavelength of light that can be more precisely controlled, which is advantageous for achieving the desired hair reduction without damaging surrounding tissue. For instance, excimer lasers can evaporate very thin layers of corneal tissue with high precision using a specific UV wavelength. While photoepilation primarily deals with light in the visible to infrared range, excimer lasers for vision correction emit UV radiation at a wavelength as low as 193 nm, allowing precise tissue removal.