Locally pixel‐compensated backlight dimming on LED‐backlit LCD TV

Abstract

Abstract— The pixel brightness of an LCD panel perceived by a user is the product of the backlight brightness and the panel transmittance. In conventional LCD panels, the backlight brightness is constant and always at peak luminance. This design suffers from light leakage and power waste problems at dark scenes. This paper presents a new LCD system, which uses locally pixel‐compensated backlight dimming (PCBD). The proposed method combines backlight control and pixel processing for reducing light leakage and power consumption while keeping the image at the original brightness. Backlight luminance is dimmed locally in the dark‐image region, and pixel values are compensated synchronously according to the luminance profile of dimmed backlight. By reducing the light leakage, a static contrast of over 20,000:1 has been achieved on a large‐sized LCD panel with the proposed PCBD method. No obvious artifacts have been noticed as well. The power consumption of the panel can also be greatly reduced, depending on various video content. The PCBD method could be widely used for developing state‐of‐the‐art LCD panels with LED backlights.