Composite optical film and manufacturing method thereof

The invention discloses a composite optical film with high luminance, high diffusions and no interference of Newton rings, which comprises a base material layer, a diffusion layer and a light condensing layer stacked in sequence, wherein the diffusion layer comprises a particle group which comprises a plurality of particles adjacent to the base material layer and a diffusion layer resin fixing the particle group; the light condensing layer comprises a light condensing layer resin, forms a light outlet surface and a microstructure unit capable of collectively emitting light rays; and the microstructure unit comprises a plurality of main microstructures regularly arranged. The composite optical film is characterized in that: a joint surface for joining the diffusion layer with the light condensing layer is formed to trend to the particle group periphery; the diffusion layer is provided with a plurality of bulges each covering at least one particle respectively; and the microstructure unit also comprises a plura