IPL with radio frequency is an effective treatment for various kinds of pigmentation issues. It is sometimes called photorejuvenation, or when performed on the face, a photofacial.
IPL consists of sophisticated flash gun that is flashed into the treatment area, heating the brown coloured melanin in the pigment causing it to break down. You may notice that the pigment darkens.
This process is repeated over the entire treatment area. Over the next few weeks, the pigmented area may darken further, and produce a rough texture called micro-crusting. In due course, just like a scab, it slowly comes off by itself, until one day, it may just fall off leaving lighter skin below.
An average of 3-6 treatments are usually required about a month apart, but a few people are lucky in that one treatment is sufficient. Lighter skin types respond better, and dark skin may not be suitable for treatment.