Abstract: Miniaturized UV detection apparatus is disclosed comprising a low voltage UV bulb and detector. Bulb and detector are arranged in juxtaposition with their optical axes essentially parallel. Optical means are provided to focus the light from the bulb onto, for example, a forged banknote (bill). The paper onto which most banknotes are printed does not fluoresce under TV light but that commonly used by forgers does. If the note fluoresces, it is probably a forgery and the flouresced light is focused by the optical means onto the detector causing an output signal to be generated and passed to discriminating circuitry which operates means to accept genuine notes and reject forgeries, according to the magnitude of the signal. The PCB on which the components are mounted also acts as a screen between bulb and detector to stop light from the bulb reaching the detector. The components are located in a sleeve and are protected by insulating and thermally conducting potting compounds.