Abstract: A device is described using at least one polyconductor film as an active ment lens of an electrical circuit for detecting incident laser radiation. In several alternative embodiments, a polyconductor film is located at the focal point of at least one lens which focuses the incident laser radiation on the film. The polyconducting film acts as a variable resistor of a balanced bridge network and upon receipt of radiation causes an imbalance in the bridge for radiation detection. The film changes phase with increasing incident power such that it protects itself against high levels of radiation. The lenses can also be polyconducting films and another film shielded from the radiation may be included to compensate for temperature fluctuations and maintain circuit sensitivity.