Abstract: An apparatus for displaying chemical projects a chemical image of an object back onto that object. At region (23) light travels from the object to the apparatus (20) and back from the apparatus as it projects onto the object. Light (24) from the object (22) (which is illuminated by natural light) passes through an objective lens (31) of the apparatus. In its path is rotating mirror (25) and when the mirror is parallel to the path of the rays of light (24), the light is allowed to pass on to hyperspectral camera (26) which is of the AOTF type. The output from the camera is transmitted to processor (27) where the chemical image is generated from the hyperspectral data. The camera generates a series of monochromatic images that are passed to the processor and the chemical image is built up as the camera scans through the appropriate wavelengths. The image data is then transmitted to a projector (28) whose output image is focussed by lens (30) towards the rotating mirror (25).