The invention relates to a hair-shortening device. The device is based on the principle of laser-induced optical breakdown, wherein a laser pulse causes mechanical effects in tissue, which are used to cut the hair (20). The invention uses the insight that, when two or more such laser pulses are provided simultaneously, the mechanical effects can co-operate. This in turn allows cutting of the hair (20) with less total energy, down to about half the energy required for cases with pulses that are supplied sequentially. In one embodiment, the device comprises a laser source (2), a grating (6), and a beam manipulator (8), that aim a plurality of simultaneous focal spots (10) into a hair (20).
