TECHNOLOGY FOCUS - POLYMERS - Preferred Layer: The epoxy resin layer further contains cycloaliphatic epoxy resin. The epoxy resin layer contains (in wt.%) bisphenol S type epoxy resin (3-60) and light diffusion agent (0.1-30).Preferred Property: The light diffusion agent has average particle diameter of 10 nm to 100 microns. Refractive index difference of bisphenol S type epoxy resin and light diffusion agent is 0.03-0.1. The sheet has glass transition temperature of 170degreesC or more and light transmittance of 88% or more. Fracture strength of the resin sheet is more than 60 N, as found by the following method. The resin sheet, which gives damage of 1 microns-depth to reverse side of 2000 paper, is interposed between surface of completely flat plate and flat plate having 20 mm-diameter hole. The plate structure is installed in horizontal direction, and four corners are fixed. A load is applied to central portion of the structure having area of 20 mm-diameter, at which the resin sheet is exposed, by a bearing bar from front-orthogonal direction. The bearing bar has globular tip of 10 mm diameter.Preferred Sheet: The resin sheet further laminates hard coat layer (3) and gas barrier layer (2). EXAMPLE - 3,4-epoxy cyclo hexyl methyl-3,4-epoxy cyclohexane carboxylate (in weight parts) (26.6) of formula (2), bisphenol S-type epoxy resin (26.6) of formula (1), methyl hexahydrophthalic anhydride (45.8) of formula (3), tetra-n-butyl phosphonium of formula (4) and o-diethyl phosphoro dithioate (1), were stir-mixed to form epoxy resin liquid.    AEROSILR9744 (silica particle) (8.4) having average particle diameter of 12 nm, was added to the epoxy resin liquid (840) to prepare particle-containing epoxy resin liquid. A particle dispersion type resin sheet was obtained using the obtained resin liquid. The epoxy resin layer had refractive index of 1.3. The sheet had glass transition temperature of 202degreesC, light transmittance of 91%, fracture strength of 120 N and favorable coating property.