Every hair removal system, specified properly.

A laser emits one coherent wavelength. Every photon leaving the handpiece is doing the same job, so the energy that reaches the follicle is predictable and you can calculate a fluence that works. IPL emits a broad band of light through a cut-off filter — useful light plus a lot of light that only heats the surrounding tissue.

Wavelength is what decides who you can treat. Shorter wavelengths are absorbed strongly by melanin, which is efficient on light skin with dark hair and risky on deeper phototypes because epidermal melanin competes for the same energy. Longer wavelengths pass the epidermis more safely, which is why 1064 nm Nd:YAG is the standard answer for skin types V and VI.

Melanin absorption falls as wavelength climbs, so a 1064 nm system needs higher fluence and good cooling to do the same work as a 755 nm system. That trade-off — safety against efficiency — is the whole specification decision, and it is why multi-wavelength platforms exist.