Camera Users:

Gert Nutzel, Leon Bosch and Rob Schomaker, Delft Electronic Products

Image intensifier tubes produce images in low-light situations, but the best tool for an application is not always obvious to the subjective human eye.

Astronomy, surveillance and broadcast television use image intensifier tubes to assist in producing images of low-light scenes such as nighttime sporting events. Through several generations of technology, these tubes have evolved in sensitivity, reliability and image quality.

Because the lighting, contrast and scenery reflection of a scene will greatly affect image intensifier tube performance, the best way to evaluate a tube for a given application is with a field test. The best tube at low light conditions may not be the best choice under better illumination. In addition, the tube's spectral performance is important: Because of differences in spectral behavior, a tube that is superior in a desert might not be in a forest.

Not all of an image intensifier tube's specifications contribute to meeting an end user's performance needs. In a specific application, one of these parameters may be so important that a user can trade off one "poor" specification for a better specification on the important parameter. For example, in low-light situations, the camera's signal-to-noise ratio can be more important than maximum output brightness.