A strobe light provides uniformly intense, monochromatic illumination of an object photographed by a video camera. The strobe light includes a circuit board having a central aperture and a plurality of light-emitting diodes mounted on the circuit board and generally surrounding the aperture. The circuit...http://www.google.de/patents/US5010412?utm_source=gb-gplus-sharePatent US5010412 - High frequency, low power light source for video camera
