Transparent support, optical film, polarizing plate and image display device

A transparent support comprising:

• a cellulose acylate film containing a light-transmitting particle having an average particle diameter of 6 to 20 μm,
• wherein
• the transparent support has a thickness of from 20 to 200 μm,
• the light-transmitting particle is contained in a ratio of 0.5 to 20 mass % based on entire solid content in the transparent support,
• the transparent support has an arithmetic average roughness (Ra) of 0.05 μm or less,
• a difference between a refractive index of the light-transmitting particle and a refractive index of the transparent support is from 0.001 to 0.05,
• the cellulose acylate film has a multilayer structure comprising a base layer and a surface layer,
• the light-transmitting particle is contained only in the base layer,
• a haze value attributable to an interior of the transparent support is from 10 to 30%, and
• a haze value attributable to a surface of the transparent support is less than 2%.