There are two big differences between Laser and Intense Pulsed Light (IPL) systems. One is in the area that can be treated in one go and the treatment speed. Generally IPL treatment heads are up to 6 times larger than the small spot produced by lasers and therefore treatments are much quicker.
The other difference is the wavelength of light produced. Lasers produce light with one specific wavelength whilst IPL uses an entire waveband. Different wavelengths penetrate the skin to different depths so using IPL is like using a group of lasers in a single treatment.
In summary, the efficacy of IPL and laser hair removal is now generally accepted in the dermatology community.