Optical element, and illuminating optical device, display device and electronic device using the same
AssigneeNEC LCD Technologies, Ltd.
InventorsKoji Mimura, Ken Sumiyoshi
Life of this patent
Estimating the term…
Abstract
A microlouver includes a periodic structure in which a transparent layer and a light absorption layer are alternately disposed with a constant, repetitive period. The range of the exit direction of a light beam passing through the transparent layer is restricted by the light absorption layer. The periodic structure includes a periodic structure portion divided in the direction that intersects the direction in which the transparent layer and the light absorption layer are repeatedly disposed. In the periodic structure portion, between the periodic structures adjacent to each other, there is a difference of 180 degree in the phase of spatial frequency of each periodic structure.
Claims25
An optical element, comprising a periodic structure in which a transparent layer and a light absorption layer are alternately disposed on a plane with a constant, repetitive period, said light absorption layer restricting a range of an exit direction of a light beam passing through said transparent layer, wherein
- said periodic structure includes a plurality of periodic structure portions divided in a direction which intersects a direction in which said transparent layer and said light absorption layer are repeatedly disposed, and at least a part of said plurality of periodic structure portions has a phase of spatial frequency that is different from a phase of spatial frequency of another part of said plurality of periodic structure portions.
An illuminating optical device comprising:
- an optical element which comprises a periodic structure in which a transparent layer and a light absorption layer are alternately disposed on a plane with a constant, repetitive period, said light absorption layer restricting a range of an exit direction of a light beam passing through the transparent layer, and
- a surface light source provided on a back surface of said optical element, wherein
- said periodic structure includes a plurality of periodic structure portions divided in a direction which intersects a direction in which said transparent layer and said light absorption layer are repeatedly disposed, and at least a part of said plurality of periodic structure portions has a phase of spatial frequency that is different from a phase of spatial frequency of another part of said plurality of periodic structure portions.
An optical element, comprising a periodic structure in which a transparent layer and a light absorption layer are alternately disposed on a plane with a constant, repetitive period, said light absorption layer restricting a range of an angle of a light beam passing through said transparent layer, wherein
- said periodic structure includes a plurality of periodic structure portions divided in a direction which intersects a direction in which said transparent layer and said light absorption layer are repeatedly disposed, and at least a part of said plurality of periodic structure portions has a phase of spatial frequency that is different from a phase of spatial frequency of another part of said plurality of periodic structure portions.
Dependencies are inferred from the claim text.