A well known problem with television cameras of the optical scanning type is the small amount of light available to the camera pickup. The intermediate film system used in the 1930's provided a clumsy form of optical storage that overcame this problem and at the time it was the only way to provide high definition optical scanning for outdoor use due to small scanning aperture size.
Another way to provide optical storage for television cameras of the optical scanning variety is with an image intensifier tube. The image intensifier tube provides a relatively bright phosphor display of a relatively dim image focussed on its photocathode. The optical scanning element may then scan the bright image intensified phosphor display of the image intensifier tube.