| 摘要 |
This disclosure provides systems, methods and apparatus for providing stacks of optical films that may be used to provide increased on-axis display brightness. In one aspect, an apparatus or system may be provided that includes a light source, a first optical film having triangular cross-section, prismatic light-turning structures, and a second optical film having trapezoidal cross-section, prismatic light-turning structures. The first optical film may be interposed between the light source and the second optical film. In further aspects, a third optical film, similar to the first optical film, may be interposed between the light source and the first optical film. In yet further aspects, one or more additional optical films, similar to the second optical film, may be positioned in the stack such that the second optical film is between the first optical film and the additional optical film(s). |
| 主权项 |
1. An apparatus comprising:
a first optical film having a first surface and a second surface located opposite the first surface of the first optical film; and a second optical film having a first surface facing the first optical film and a second surface located opposite the first surface of the second optical film, wherein:
the second surface of the first optical film is defined by a plurality of prismatic light-turning structures,each prismatic light-turning structure that is included in the plurality of prismatic light-turning structures that defines the second surface of the first optical film has a substantially triangular cross-section,the second optical film includes a plurality of prismatic light-turning structures,each prismatic light-turning structure of the plurality of prismatic light-turning structures included in the second optical film has a trapezoidal cross-section,each trapezoidal cross-section widens with increasing distance from the first optical film, and the first optical film and the second optical film are positioned in a stacked arrangement with the second surface of the first optical film facing towards the first surface of the second optical film. |
