An electro-optical power amplier and trigger circuit

If electroluminescent cells and photo-conductor cells are placed in optical vicinity, the combination can be used as a power amplifier for electrical signals. Whereas in vacuum tubes control is exerted by an electric field, and in magnetic amplifiers by a magnetic field, this new amplifier type uses light as a control medium. Static power gains up to 40 db have been readily achieved, although the frequency response is, at present, not satisfactory for audio purposes.