Abstract: Disclosed is a film speed control device for a single-system sound camera capable of simultaneous picture/sound recording in which an intermittent film transport mechanism at the exposure station and a constant speed film transport mechanism at a sound station having a magnetic recording head are driven synchronously by separate drive motors. In the control device, the impedance of a high frequency coil is changed in response to changes in the size of a film loop between the stations to control the rate of operation of the intermittent film transport so as to maintain constant the size of the film loop. The output of the high frequency oscillator is used for AC bias for the magnetic recording head, and is rectified for use as a power source for the recording amplifier.

Abstract: This invention relates to a short focal length, large aperture Petzval-type optical system primarily designed to efficiently transmit light rays to an image plane with an extraordinarily high degree of correction over a prescribed field.

Abstract: This invention relates to a short focal length, large aperture optical system primarily designed to efficiently transmit light rays to an image plane with an extraordinarily high degree of correction over a prescribed field.