NOVELTY - Optically addressed spatial light modulator has substrate (1b) sequentially provided with transparent electrode (2b), photoconductive layer (3), light-blocking layer (4), dielectric mirror layer (5), transparent electrode (2a), and transparent substrate (1a).    USE - For optical display system, optical signal processing system (both claimed), light modulation device, and projectors used to display images having pre-dimensional component such as holographic display and autostereoscopic displays.    ADVANTAGE - The optically addressed spatial light modulator allows more efficient separation of input and read lights and increases the read light reflection, resulting in improvements to the input sensitivity, image-resolution, contrast ratio, sheet resistance, and diffraction efficacy. The materials used in the photoconductor, light-blocking layer and dielectric mirror are closely related and the manufacture steps is reduced resulting in cheap and more reliable products.    DETAILED DESCRIPTION - Optically addressed spatial light modulator comprises:    (I) substrate (1b) sequentially provided with:    (II) transparent electrode (2b);    (III) photoconductive layer (3) comprising hydrogenated amorphous silicon carbide;    (IV) light-blocking layer (4) comprising hydrogenated amorphous carbon;    (V) dielectric mirror layer;    (VI) transparent electrode (2a); and    (VII) transparent substrate (1a).    A liquid crystal layer (8) is provided between orientation units.    INDEPENDENT CLAIMS are included for the following:    (1) a method of manufacturing optically addressed spatial light modulator (OASLM) which involves forming photoconductive layer, light-blocking layer, and dielectric multi-layer mirror based on alternating hydrogenated amorphous silicon carbide (a-Si:C:H) layers having high refractive index and hydrogenated amorphous carbon (a-C:H) layers having low refractive index, sequentially on the substrate (1b);    (2) an optical display system incorporating OASLM; and    (3) an optical signal processing system incorporating OASLM.    DESCRIPTION OF DRAWING(S) - The figure shows the cross-sectional view of reflective-type liquid crystal spatial light modulator.    Transparent substrate (1a,1b)    Transparent electrode (2a,2b)    Photoconductive layer (3)    Light-blocking layer (4)    Dielectric mirror layer (5)    Orientation units (6a,6b)    Liquid crystal layer (8)