Imaging system.

摘要

In an imaging system suitable for example for use as a firearm night sight a primary object viewable from viewing position (10) is formed by objective optics (17) and an image intensifier tube output face (11). A secondary image is formed by edgewise illumination of a glass plate (15), the plate (15) carrying a diffusion graticule pattern. Both images are formed in monochromatic light at chromatically separate wavelengths. A glass plate (18) has a dichroic surface (19) transmissive to the wavelength of light from the secondary object (14). Both lengths from the primary object to dichroic surface (Z2) are arranged to be optically equal, so that superimposed images may be viewed. The invention provides a correctly focussed secondary image, without optical components close to the intensifier output face or off axis image projection.