Flat Panel TVs: Understanding Your Options
Single-TV homes are rare today. The flat-panel
technologies (Plasma, LCD, LED, now OLED)
now available at popular prices make it practical
to locate TV displays in almost any room in the home—even outdoors. LED (Light Emitting Diode) TVs, featuring a very thin design and low power consumption, are currently the most popular, available in a very wide range of sizes. Plasma TVs, long valued for their exceptional contrast, accurate color rendition, and wide viewing angles, are now being replaced by OLED (Organic LED) models, which combine the advantages of LED and Plasma technologies. LCD (Liquid Crystal Display) TVs, long the staple of the industry, have been eclipsed by LED technology, and are now available mostly as entry level models in smaller sizes.
Also noteworthy is the new Ultra High Definition (UHD or 4K) video, which provides four times the resolution of the current High Definition (1080p) standard. Now increasingly available in LED TVs, it is about to be combined with OLED technology to offer the ultimate in viewing experience, with the highest contrast, resolution, and color fidelity!
LCD (Liquid Crystal Display) These TVs form a picture using the same basic technology found in laptop computers and monitors. They produce a brighter picture than Plasma TVs, and may perform better under difficult lighting conditions—although no TV looks good under bright lights. For highest image quality and lowest viewing fatigue, control the ambient light! Early LCD TVs suffered from poor off-axis performance (viewing from the side or below), marginal color fidelity, low usable contrast, and poorer performance in scenes with rapid motion. Recent advances have significantly reduced these limitations.
LED (Light Emitting Diode) TVs employ the same liquid crystal pixel technology as LCDs to create the picture. But instead of using the LCD’s single fluorescent tube behind the pixel array to light the image, LED TVs have groups of light emitting diodes, arrayed either behind the pixels (back lit) or around the edge of the TV (edge lit). The edge-lit LEDs use light baffles to distribute the light evenly across the screen. This arrangement allows these TVs to be very thin (currently as little as 1.2 inches), but can produce slightly uneven illumination across the picture, with brighter corners.
LED with Local Dimming Back-lit LED TVs aren’t quite as thin, but provide more even illumination than the side-lit models. Some higher-priced models provide a local dimming feature: they analyze the brightness needed for each part of the scene to be displayed, then selectively dim the LEDs behind the brighter sections to eliminate blown-out details (like in snow scenes) and/or selectively brighten other areas of the picture when needed (for shadow detail). Local dimming allows LED TVs to approach the dynamic range and color fidelity of plasma technology (where each pixel generates its own light).
OLED (Organic LED) This new TV technology works without a back light, and is capable of wider contrast range and greater color accuracy than even plasma TVs. Also, they are very thin and flexible, and can be made in curved forms. OLED TVs are now available from several manufacturers at premium prices. Because of their superior performance, this technology is destined to become very popular as prices drop. See An Insider’s Guide to Home Theater.