Light emitting diode (LED) backlight with reduced hotspot formation

• Main Authors: SHI JIANRU, GANDHI JIGNESH, MI XIANGDONG
• Format: Patent
• Language: English
• Published: 13.01.2016
• Subjects: BLASTING; FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMSTHEREOF; HEATING; LIGHTING; MECHANICAL ENGINEERING; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHERARTICLES, NOT OTHERWISE PROVIDED FOR; WEAPONS

This disclosure provides systems, methods and apparatus for reducing hotspots in backlit displays. Hotspot artifacts in multi-color backlit displays can be reduced by incorporating optical structures along the edges of light guides incorporated into the backlights. The optical structures are positioned adjacent to light emitting modules that emit light into the light guide. Light emitted from the light emitting modules passes through the optical structures before entering the light guide. Hotspot size can be reduced by appropriately configuring the shapes and sizes of these optical structures. In some implementations, the optical structures may include serrations along the side of the light guide adjacent to the light sources. In some other implementations, the optical structures may include dimples. Size of hotspots may also be reduced by reducing the distance between adjacent light sources of the same color.