Illumination light source device e.g. for photographic printer

摘要

A lamp (S) emits light when heated which passes through a condenser to illuminate a film used for a photographic copying process. A device which selectively reflects only infrared radiation in the direction of the lamp is arranged in an optical path extending between the condenser to the film. The infrared reflecting device is an infrared reflecting plate (RP) arranged at right angles to an optical axis of the condenser device. The plate reflects infrared but passes visible light. A total reflection mirror can be arranged on the side of the plate on which the infrared is incident and perpendicular to the condenser's optical axis.