Transmissive screen and rear projection type image display apparatus using same
View Patent ↗A purpose of the present invention is to provide a simple configuration for bonding a lenticular lens sheet, a front sheet, and light diffusion layers together to reduce cost. To accomplish the above purpose, the present invention comprises: a lenticular lens sheet ( 20 ); a front sheet ( 30 ); a first adhesive layer ( 35 ) for bonding the lenticular lens sheet ( 20 ) and the front sheet ( 30 ) together, the first adhesive layer ( 35 ) being disposed between the lenticular lens sheet ( 20 ) and a light incident side of the front sheet ( 30 ); an AR film ( 40 ); and a second adhesive layer ( 36 ) for bonding the front sheet ( 30 ) and the AR film ( 40 ) together, the second adhesive layer ( 36 ) being disposed between a light exit side of the front sheet ( 30 ) and the AR film ( 40 ); wherein light diffusion materials are spread in the first and second adhesive layers to add a light diffusion function to the layers.
1. A transmissive screen used for a rear projection type image display apparatus, comprising:
a first sheet having a Fresnel lens formed on a light exit surface thereof;
a second sheet having plural lens elements formed on a light incident surface thereof, the plural lens elements diffuse light from said first sheet;
a first diffusion layer formed of an adhesive material containing a light diffusion material for diffusing light and positioned on a light exit surface of said second sheet; and
a second diffusion layer formed of an adhesive material containing a light diffusion material for diffusing light and positioned on a light exit surface of said second sheet;
wherein,
said second diffusion layer is set in a position in a viewer side direction of said first diffusion layer, the position being separate at a set distance from said first diffusion layer; and
said transmissive screen is configured to satisfy the expression:
T D =t D *θ 2 ,
where: θ 2 is the half-value light divergence angle of said second diffusion layer; t D is said set distance; TD is a light diffusion width given by said second diffusion layer.
2. The transmissive screen as claimed in claim 1 , wherein said second sheet further comprises a front sheet sandwiched between said first diffusion layer and second diffusion layer.
3. A transmissive screen used for a rear projection type image display apparatus, comprising:
a first sheet having a Fresnel lens formed on a light exit surface thereof;
a second sheet having plural lens elements formed on a light incident surface thereof, the plural lens elements diffuse light from said first sheet;
a third sheet;
a first diffusion layer formed of an adhesive material containing a light diffusion material for diffusing light; and
a second diffusion layer formed of an adhesive material containing a light diffusion material for diffusing light;
wherein,
said second sheet and said third sheet are combined by said first diffusion layer;
said third sheet is sandwiched between said first diffusion layer and second diffusion layer; and
said transmissive screen is configured to satisfy the expression:
T D =t D *θ 2 ,
where: θ 2 , is the half-value light divergence angle of said second diffusion layer; t D is said set distance; T D is a light diffusion width given by said second diffusion layer.
4. The transmissive screen as claimed in claim 3 , further comprising an antireflective film, wherein:
said third sheet and said antireflective film are combined by said second diffusion layer.
5. The transmissive screen as claimed in claim 3 , wherein:
said lens elements are lenticular lenses that extend in a vertical direction of said screen, said lenticular lenses being arranged in a horizontal direction of said screen.
6. The transmissive screen as claimed in claim 3 , wherein:
said second sheet has a light absorbing portion on a light exit surface thereof, and said first diffusion layer is positioned between said light absorbing portion and said third sheet.