Ignition circuitry for secondary flash lamps - with increased sensitivity to light but not to room light

摘要

The circuit for igniting secondary flash lamps from the light pulse of a first flash lamp comprises a photoelectric element (1) which receives the light pulse and which controls an electronic switch (2) pref. a thyristor to the output of which are connected the synchronous in puts of the secondary flash lamps. The photoelectric element is coupled to the control electrode of the electronic switch via a transformer (6) of which the primary winding has a low d.c. resistance and a high inductive resistance. The transformer is preferably and auto-transformer.