Quantum cascade lasers, A novel lightsource for mid-infrared sensor systems

A shaving unit for electric shaver comprising a comb provided with a plurality of perforations of rectangular shape, said perforations being spaced from one another and being arranged along sloping parallel rows forming an angle of about 10 DEG with the longitudinal axis of the comb, the perforations of two adjacent rows being staggered between each other, and the comb having the form of a continuous curve consisting of three waves, and three shaving elements of semitubular shape for engaging the comb at the waves to cut hair received in the perforations of the comb.