CV6099 image converter tube. These are sensitive to infrared light out to a wavelength of about 1 micron but the luminous gain of systems using them is approximately 1, so a source of infrared light would be needed if they were being used at night. They were developed in the late 1950s and are essentially an improved version of image converter tubes used as far back as 1934. They were typically used throughout the 1960s in various pocket-scopes, binoculars, tank periscopes etc., and were replaced through the 1970s and 1980s by image intensifiers using ambient light and by thermal imaging systems.
The fluorescent screen needs a minimum of 8 kV to operate and the current is 0.1 μA.
The photocathode. The system resolution is given as a maximum of 50 line pairs per mm on the main axis.
The original packing is a screw lid tin 65 mm in diameter and 116 mm tall.
The rest of the main label.
Storage requirement and the need to keep the cell in the dark when not connected.
Inside the lid is an expanded polystyrene disc.
Within are two expanded polystyrene half cylinders and a warning label.
The warning label from a second example.
This tin measures 56 mm diameter and 95 mm tall. The lid is a push fit and was secured with adhesive tape.
The glass envelope is 30 mm in diameter and, is 58 mm tall.