FIELD: optical engineering. SUBSTANCE: device has mirror shaped as hollow sphere with internal mirror coating and light source mounted inside of the sphere. Lens having elliptic surface is mounted in lateral opening of the sphere. Glass plate, gradient lens and light guide are fitted close to each other. Radiation is issued as from the elliptic lens as quasi-parallel beam and reaches glass plate manufactured from material having refractive index essentially dependent on temperature to carry out self-focussing of the light beam. EFFECT: enhanced effectiveness optical input. 1 dwg
