An LED backlight has been designed using the flow-line design method. This method allows a very efficient control of the light extraction. The light is confined inside the guide by total internal reflection, being extracted only by specially calculated surfaces: the ejectors. Backlight designs presented here have a total optical efficiency of up to 80% (including Fresnel and absorption losses) ...

When a directional backlight to each eye alternates synchronously with the alternation of left-eye and right-eye images on the display panel, the viewer can see a stereoscopic image without wearing special goggles. One way to realize a directional backlight is to place a convex lens array in front of dot matrix light sources to generate collimated light. To implement this method, however, defoc...

Coherent backlight is an essential component for holographic displays. In this paper, a compact design of edge-lit coherent backlight featuring two holographic optical elements for two-dimensional beam expansion is presented. Its diffraction efficiency is numerically studied using the coupled-wave theory. In experiments, the diffraction efficiency is measured as 4.3% and the feasibility of this...

This chapter presents transmittance scaling; a technique aimed at conserving power in a transmissive TFT-LCD with a cold cathode fluorescent lamp (CCFL) backlight by reducing the backlight illumination while compensating for the luminance loss. This goal is accomplished by adjusting the transmittance function of the TFT-LCD panel while meeting an upper bound on a contrast distortion metric. Exp...

We report a systematic photometric study of LCD based on quantum dot (QD) backlight, and find the optimal emission spectrum combination in terms of system efficiency and wide color gamut. A QD-based LCD has potential to achieve 120% AdobeRGB color gamut in CIE 1931 and 140% in CIE 1976 color space, while keeping the same energy efficiency as conventional backlights. Moreover, we present a trans...

This report describes a quantification method for luminance non-uniformity of a large LED backlight. In experiments described herein, participants subjectively evaluated artificial indistinct Mura images that simulated luminance non-uniformity of an LED backlight. We measured the luminance distribution of the Mura images. Then, the measured luminance distribution was converted into S-CIELAB, in...

Despite the limited power available in a battery-operated mobile embedded system, its display must have an enough resolution and sufficient color depth to support quality graphical user interfaces and multimedia applications. An LCD (Liquid Crystal Display) is a standard display device, and a color TFT (Thin-Film Transistor) LCD is common even in a low-cost equipment. An LCD display system is c...

A Backlight Module is the main source supply of liquid crystal display components. Its power consumption is about half the liquid crystal display. Among the Backlight Module, BEF / DBEF enhances luminance 50% to 100%. Therefore BEF (Brightness Enhancement Film) / DBEF (Dual Brightness Enhancement Film) becomes the main critical component of Backlight Module. The assurance of sustaining balance ...

The local dimming backlight technique enables liquid crystal display to present images with high contrast ratio and low power consumption. Considering that it is more important to make sure a high quality of the displayed image when reducing the power consumption, therefore, in this paper the new algorithm chooses RPSNR (the peak signal-to-noise ratio) =30 as the lowest standard to guarantee th...

We analyze the color performance and system efficiency of three commonly employed liquid crystal display modes with a blue LED-pumped red and green quantum dots (QDs) backlight. Based on the measured QD emission spectra, we can achieve 115% color gamut in CIE 1931 and 140% in CIE 1976 color space, while keeping the same energy efficiency as conventional backlights. Next, we apply multi-objectiv...