Optically-calibrated backlight unit internal supports
A backlight unit for a display device comprising a chassis, a reflector affixed to the chassis, optical sheets affixed to the chassis, one or more light emitters affixed to the chassis, and optically-calibrated internal support structures. There is an air gap between the reflector and the optical sheets. The optically-calibrated internal support structures are disposed within the air gap and affixed to the chassis. The optically-calibrated internal support structures are configured to increase rigidity of the chassis, and to substantially not alter the uniformity of light emitted by the one or more light emitters through the optical sheets.
1. A backlight unit for a display device, comprising:
a chassis;
a reflector affixed to the chassis;
optical sheets affixed to the chassis, wherein there is an air gap between the reflector and the optical sheets;
one or more light emitters affixed to the chassis; and
optically-calibrated internal support structures disposed within the air gap and affixed to the chassis, wherein the optically-calibrated internal support structures are configured to increase rigidity of the chassis, to substantially not alter the uniformity of light emitted by the one or more light emitters through the optical sheets, and wherein at least one of the optically-calibrated internal support structures has a non-uniform variation in reflectivity along its length.
2. The backlight unit of claim 1 , wherein the reflector includes an optically-calibrated edge geometry, and the optically-calibrated internal support structures have an optically-calibrated edge geometry conforming to the optically-calibrated edge geometry of the reflector.
3. The backlight unit of claim 2 , wherein:
the edge geometry of the reflector and the optically-calibrated internal support structures have a cross-sectional shape including a substantially vertical section attached to the chassis and extending substantially perpendicular to a plane of the chassis, the substantially vertical section of the optically-calibrated internal support structures disposed directly above and extending away from an upper surface of the reflector, and a sloped section extending from the vertical section; and
the vertical section and the sloped section comprise a first portion of a symmetric shape having two mirror-symmetric portions.
4. The backlight unit of claim 1 , wherein for at least one of the optically-calibrated internal support structures, a surface of the internal support structure has a plurality of dots, each dot altering reflectivity of the surface and having a size related to the distance from a center of the dot to the one or more light emitters.
5. The backlight unit of claim 1 , wherein an edge geometry of the optically-calibrated internal support structures has a cross sectional shape including a sloped section extending from a plane of the chassis at an angle between 25 and 40 degrees.
6. The backlight unit of claim 1 , wherein an edge geometry of the optically-calibrated internal support structures has a cross sectional shape including a horizontal section substantially parallel to the chassis, and a vertical section extending from the horizontal section and substantially perpendicular to the horizontal section and chassis.
7. A display device, comprising:
a display screen; and
a backlight unit configured to illuminate the display screen, the backlight unit including:
a chassis;
a reflector affixed to the chassis, the reflector including an optically-calibrated edge geometry;
one or more light emitters affixed to the chassis;
optical sheets affixed to the chassis, wherein there is an air gap between the reflector and the optical sheets; and
optically-calibrated internal support structures disposed within the air gap and affixed to the chassis, wherein the optically-calibrated internal support structures have an optically-calibrated edge geometry conforming to the optically-calibrated edge geometry of the reflector, and wherein at least one of the optically-calibrated internal support structures has a non-uniform variation in reflectivity along its length.
8. The display device of claim 7 , wherein the edge geometry of the reflector and the optically-calibrated internal support structures have a cross-sectional shape including a vertical section attached to the chassis and extending substantially perpendicular to a plane of the chassis, and a sloped section extending from the vertical section.
9. The display device of claim 8 , wherein the sloped section extends at an angle of between 10 and 60 degrees relative to the plane of the chassis.
10. The display device of claim 8 , wherein the vertical section and the sloped section comprise a first portion of a symmetric shape having two mirror-symmetric portions.
11. The display device of claim 7 , wherein the edge geometry of the optically-calibrated internal support structures extends from a plane of the chassis to a cross-sectional height of between one eighth and one half of a height of the air gap between the reflector and the optical sheets.
12. A backlight unit for a display device, comprising:
a chassis;
a reflector affixed to the chassis;
one or more light emitters affixed to the chassis;
optical sheets affixed to the chassis, wherein there is an air gap between the reflector and the optical sheets; and
optically-calibrated internal support structures disposed within the air gap and affixed to the chassis, wherein the optically-calibrated internal support structures have a non-uniform variation in reflectivity along a length of the internal support structures, and wherein the optically-calibrated internal support structures have a height that is less than a height of the air gap between the reflector and the optical sheets.
13. The backlight unit of claim 12 , wherein the reflector has a non-uniform variation in reflectivity along a length of the reflector, substantially similar to the non-uniform variation in reflectivity along the length of the internal support structures.
14. The backlight unit of claim 12 , wherein the non-uniform variation in reflectivity corresponds to a distance from points along the length of the length of the internal support structures to the one or more light emitters.
15. The backlight unit of claim 12 , wherein a surface of the internal support structures has a plurality of dots, each dot altering reflectivity of the surface and having a size related to the distance from a center of the dot to the one or more light emitters.
16. The backlight unit of claim 15 , wherein the relationship of the size of each dot to the distance from the center of the dot to the one or more light emitters includes increasing the size of a dot having a center closer to a closest light emitter of the one or more light emitters.
17. The backlight unit of claim 12 , wherein the non-uniform variation in reflectivity includes a non-uniform variation in absorption.
18. The backlight unit of claim 12 , wherein the non-uniform variation in reflectivity includes a non-uniform variation in diffusivity.