Transmissive screen and rear projection type image display apparatus using same

A transmissive screen used for a rear projection type image display apparatus, which includes:

• a light source;
• a display element which modulates light intensity to change a shade of light from said light source for each pixel according to an image signal and thereby form an optical image;
• and
• a projection lens which enlarges said optical image formed by said display element;
• wherein said optical image enlarged by said projection lens is projected to a rear surface of said transmissive screen;
• wherein said transmissive screen comprises:
• (a) a Fresnel lens sheet having a concentric Fresnel lens formed on a light exit surface thereof;
• (b) a lenticular lens sheet having a plurality of lenticular lenses formed on a light incident surface thereof and further having light transmissive portions and light absorbing layers arranged alternately on a light exit surface thereof in a horizontal direction of said screen,
• said plurality of lenticular lenses being arranged in said horizontal direction of said screen and extending in a vertical direction of said screen,
• each light transmissive portion being disposed at a focal position of a respective one of said plurality of lenticular lenses,
• each light shielding layer being disposed at a position corresponding to a respective one of boundaries between said plurality of lenticular lenses;
• (c) a first adhesive layer in which is spread a light diffusion material for diffusing light;
• (d) a front sheet;
• and
• (e) a second adhesive layer in which is spread a light diffusion material for diffusing light;
• and
• wherein said Fresnel lens sheet, said lenticular lens sheet, said first adhesive layer, said front sheet, and said second adhesive layer are arranged in that order in a traveling direction of said optical image.

A rear projection type image display apparatus comprising:

• a light source;
• a display element which modulates light intensity to change a shade of light from said light source for each pixel according to an image signal and thereby form an optical image;
• a projection lens which enlarges and projects said optical image formed by said display element;
• a mirror which reflects said optical image projected from said projection lens;
• and
• a transmissive screen which receives on a rear surface thereof said optical image reflected from said mirror;
• said transmissive screen including:
• (a) a Fresnel lens sheet having a concentric Fresnel lens formed on a light exit surface thereof;
• (b) a lenticular lens sheet having a plurality of lenticular lenses formed on a light incident surface thereof, and further having light transmissive portions and light absorbing layers arranged alternately on a light exit surface thereof in a horizontal direction of said screen,
• said plurality of lenticular lenses being arranged in said horizontal direction of said screen and extending in a vertical direction of said screen,
• each light transmissive portion being disposed at a focal position of a respective one of said plurality of lenticular lenses,
• each light shielding layer being disposed at a position corresponding to a respective one of boundaries between said plurality of lenticular lenses;
• (c) a first light diffusion layer which is bonded to said light transmissive portions and said light shielding layer positioned on a light exit surface of said lenticular lens sheet and in which a light diffusion material for diffusing light is spread;
• (d) a front sheet;
• (e) a second light diffusion layer in which a light diffusion material for diffusing light is spread;
• and
• (f) an antireflective film for reducing reflection of ambient light;
• wherein said Fresnel lens sheet, said lenticular lens sheet, said first light diffusion layer, said front sheet, said second light diffusion layer, and said antireflective film are arranged in that order in a traveling direction of said optical image;
• and
• wherein said lenticular lens sheet, said first light diffusion layer, said front sheet, said second light diffusion layer, and said antireflective film are bonded together into a composite sheet.