Integrated Back Light Unit Including Non-Uniform Light Guide Unit

• Main Authors: KANESHIRO Ronald, WANG Ping, JANSEN Michael, PATTERSON Frank, CARLISLE Clinton
• Format: Patent
• Language: English
• Published: 17.08.2017
• Subjects: BLASTING; FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMSTHEREOF; HEATING; LIGHTING; MECHANICAL ENGINEERING; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHERARTICLES, NOT OTHERWISE PROVIDED FOR; WEAPONS

An integrated back light unit can include a light guide plate having a non-uniform distribution of extraction features. The non-uniform distribution of the extraction features can be provided by an extraction-feature-free region in proximity to a light emitting device, and/or by a variable density of the extraction features that changes with distance from the light emitting device. Additionally or alternatively, the light guide unit can include a heterogeneous reflectivity surface that has a different reflectivity at proximity to the light emitting device assembly than at a distal portion of the light guide unit. The different reflectivity may be provided by a specular reflective material, diffusive reflective material, or a light absorbing material. The non-uniform distribution of extraction features and/or the heterogeneous reflectivity surface can be employed to enhance brightness uniformity of the reflective light and/or to control the temperature distribution within the light guide unit.