Cinemax Image Intensifier For High Speed Cameras

Abstract

An intensifier has been developed for use with high speed cine cameras, high speed video and image converter cameras. The Cinemax intensifier gives a real increase in sensitivity of at least 100x for white light events. This can be further enhanced by using wider aperture lenses than are possible with high speed cine cameras. Normally image intensifiers cannot be used in front of high speed cameras because long phosphor decay times cause image stacking. Rapidly changing events become smeared, resulting in poor resolution and low contrast. Cinemax is the first high brilliance intensifier to use sub-microsecond decay phosphors and when placed in front of an image converter camera, speeds up to 1,000,000 f.p.s. are possible. Cinemax is run in continuous mode at low light levels for setting up and in gated mode when recording a high speed sequence. The gated-on period is synchronised with event and camera and is designed to keep the energy dissipated in the final phosphor below damage threshold. Cinemax has successfully been used in conjunction with a Hyspeed cine camera to record the initial burning phase in a lean burn internal combustion engine.