Optical film and backlight system using the same
AssigneeIndustrial Technology Research Institute
InventorsYI-TING SUN, CHIA-WEI YU, YU-NAN PAO
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Abstract
An optical film with a plurality of micro structures which are capable of collecting incident light to the frontal and normalized view angle of the optical film for reducing the chance of incident light returning to light guild plate so as to enhance light collecting efficiency is provided in the present invention. In an embodiment, the optical film is combined with a flat light source so as to form a backlight system. By means of the merit of the optical film, the quantities of the optical film can be reduced so that the backlight system can have characteristics of thin thickness and low production cost.
Claims25
An optical film, comprising:
- an entrance surface, for receiving an incident light where it is refracted inside the optical film to form a refracted optical field;
- and
- an exit surface, having a plurality of microstructures formed thereon, each microstructure being configured with a first curved surface and a second curved surface, for collecting the refracted optical field to a frontal and normalized view angle of the exit surface where it is emitted;
- wherein, the incident light is composed of a first sub-field and a second sub-field while enabling a specific included angle, ranged between −50 degrees to −80 degrees, to be formed between the normal of the energy peak of the first sub-field and the normal of the entrance surface, and another specific included angle, ranged between 50 degree and 80 degree, to be formed between the normal of the energy peak of the second sub-field and the normal of the entrance surface.
A backlight system, comprising:
- a planar light source;
- and
- an optical film, being arranged at a side of the planar light source for receiving an incident light provided by the planar light source and being comprised of:
- an entrance surface, for receiving an incident light where it is refracted inside the optical film to form a refracted optical field;
- and
- an exit surface, having a plurality of microstructures formed thereon, each microstructure being configured with a first curved surface and a second curved surface for collecting the refracted optical field to a frontal and normalized view angle of the exit surface where it is emitted;
- wherein, the incident light is composed of a first sub-field and a second sub-field while enabling a specific included angle, ranged between −50 degrees to −80 degrees, to be formed between the normal of the energy peak of the first sub-field and the normal of the entrance surface, and another specific included angle, ranged between 50 degree and 80 degree, to be formed between the normal of the energy peak of the second sub-field and the normal of the entrance surface.
Dependencies are inferred from the claim text.