Abstract: This disclosure depicts a light source device for an endoscope, incorporating a lamp to supply the light to a light guide fiber bundle for the illumination of the endoscope. This light source device for the endoscope has a heat radiating device for the light guide fiber bundle for the illumination, which has been highly heated by the radiant heat of the lamp. The radiating device includes a support ring and radiator fins radially movably mounted to and supported by the support ring via resilient members. When a light inciding end portion of the light guide fiber bundle for the illumination is installed into the light source device for the endoscope, the heat radiating device is moved radially outwardly against the biasing forces of the resilient members, and the radiator fins are reliably brought into close contact with the outer periphery of the light inciding end portion of the light guide fiber bundle.

Abstract: A video signal transmission system for an endoscope converts an electrical video signal produced by a solid state image sensor into an optical signal and transmits the optical signal to a control section through a fiber optic cable or like light carrying medium. Because the fiber optic cable used for the present invention transmits light indicative of a time serial signal from the solid state imaging sensor, it will be clear that the cable may be constituted by a single length of optical fiber and, in this respect, substantially differs from usual light carrying fiber bundles which are installed in general endoscopes as image guides for transmitting light images simply as light.

Abstract: A light source provided in an endoscope is controlled to provide a constant comparatively low luminance when the object is to be observed, and to provide a first lowered and then gradually increased luminance when the object is to be photographed. The voltage and consequently, the luminance is first further lowered below the comparatively low luminance for observation when the object is to be photographed and the voltage is then increased so that a high luminance results. A control circuit is connected between a shutter release signal generating circuit and a light source to control the voltage across the light source upon receipt of the shutter release signal.