Light diffusion member, method of manufacturing same, and display device
A light diffusion member includes a light-transmissive base, a plurality of light diffusion portions, a connecting portion, and a light absorbing layer. The light diffusion portions are arranged on one surface of the base and have light-incident end surfaces each positioned on the side away from the base and having a larger area than a light-emergent end surface thereof. The connecting portion connects at least two adjacent ones of the plural light diffusion portions to each other, and is positioned near the light-incident end surfaces of the adjacent light diffusion portions. The light absorbing layer is formed on the one surface of the base in a region different from a region where the light diffusion portions are formed. A size from the light-incident end surface to the light-emergent end surface of the light diffusion portion is larger than a thickness of the light absorbing layer.
1. A method of manufacturing a light diffusion member, the method comprising:
forming a light absorbing layer, which includes openings, on one surface of a light-transmissive base;
forming a negative photosensitive resin layer, which is light-transmissive, on the one surface of the light-transmissive base, the negative photosensitive resin layer covering the light absorbing layer;
applying diffused light to the negative photosensitive resin layer through the openings in the light absorbing layer from an opposite surface of the light-transmissive base, the opposite surface being opposite to the one surface of the light-transmissive base, the light absorbing layer and the negative photosensitive resin layer being formed above the one surface of the light-transmissive base; and
developing the negative photosensitive resin layer after being irradiated with the diffused light, the developing being performed to form, on the one surface of the light-transmissive base, a plurality of light diffusion portions each including a light-emergent end surface and a light-incident end surface, the light-emergent end surface being positioned at a first side, the first side being close to the light-transmissive base, the light-incident end surface being positioned at a second side, the second side being spaced away from the light-transmissive base, the light-incident end surface having a larger area than the light-emergent end surface, the light diffusion portions being in a state that at least a portion of adjacent ones of the light diffusion portions are coupled to each other in at least a portion of regions of the light diffusion portions, the at least a portion of regions of the light diffusion portions being positioned at the second side.