HDTV stands for High-Definition Television, a type of television that provides higher resolution. That means HDTV provides better picture quality therefore better viewing experience. HDTV is a digital TV broadcasting format where the broadcast transmits widescreen pictures with more detail and quality than found in a standard analog television, or other digital television formats. HDTV is the best quality Digital TV format available.
You should be familiar with following terms before choosing one HDTV for yourself.
Contrast ratio is the ratio, which illustrates how much difference there is between the brightest whites and the darkest black colors the screen can display. The higher the ratio, the better the contrast.
Refresh rate tells us how often the display hardware will refresh or redraw the image created on the screen. The higher the refresh rate, the better your picture will be, affecting the way fast-moving images appear, reducing blurring and improving clarity. Plasma displays usually have a much higher refresh rate, with the typical screen having a 600hz refresh rate, but LCD or LED TVs have been catching up with 60, 120, 240, or even some 480hz refresh rates available.
Pixel Response Time
Similar to refresh rate, Pixel response time is the number of milliseconds the individual pixels take to react to a refreshed image. While Refresh rate deals with the time it takes the hardware to refresh the image, response time refers to how quickly the individual pixels change from one color to other. The lower the time, the better. Better response times will also create less blurry pictures for fast moving images.
Types of HDTV
Plasma TVs were the biggest revolution in TV industry after color direct-view (tube) televisions. They are called “plasma” displays because the technology utilizes small cells containing electrically charged ionized gases, or what are in essence chambers more commonly known as fluorescent lamps.
Plasma TVs are capable of producing deeper blacks allowing for superior contrast ratio.
They also have wider viewing angles than those of LCD; images do not suffer from degradation at high angles like LCDs, therefore plasma TVs deliver better picture quality to larger crowd. Because of very high refresh rates and faster response time, plasma TVs deliver superior performance when displaying content with significant amounts of rapid motion.
While they can provide some of the best images, Plasmas consume more energy and have more harmful chemicals than LEDs. Plasmas are also more vulnerable to burned-in images than LCD/LED flatscreens if users are not as careful as they should be. Plasma TVs produce more heat than LCD/LED TVs.
- Panasonic TC-P50S60 50-Inch 1080p 600Hz Plasma HDTV
- Panasonic TC-P42S60 42-Inch 1080p 600Hz Plasma HDTV
- Panasonic VIERA TC-P60ST50 60-Inch 1080p 600Hz Full HD 3D Plasma TVLG Electronics 50PN6500 50-Inch 1080p 600Hz Plasma HDTV
- LG 50PN4500 50-Inch 720p 600Hz Plasma HDTV
- Samsung PN51F5300 51-Inch 1080p 600Hz Plasma HDTV
Liquid Crystal Display or LCD TVs are quickly displacing the only major competitors in the large-screen market, the plasma display panel and rear-projection television. LCDs are, by far, the most widely produced and sold television display type.
All LCD TVs are backlit because Liquid Crystals do not emit any light. So in order to produce an image on the LCD TV display, its pixels have to be backlit by a separate lighting source. Currently, most LCD TVs use CCFL technology (cold cathode fluorescent lamps) as their backlight source. They deliver good colors and brightness, and decent contrast, but not great blacks – the domain of the plasma TV. But TVs utilizing brighter LED backlighting can achieve much better blacks, as well as brighter colors and even greater contrast ratios.
- Westinghouse CW46T9FW 46-Inch 1080p 120Hz LCD HDTV
- Samsung UN22D5003 22-Inch 1080p 60Hz LED HDTV
- LG Electronics 47LN5700 47-Inch 1080p 120Hz LED-LCD HDTV with Smart TV
- LG 47CS570 47-Inch 1080p 120Hz LCD HDTV
- Sony KDL50EX645 50-Inch 1080p 120HZ Internet Slim LED HDTV
LED televisions are actually LCD televisions that are lit with Light Emitting Diodes as opposed to the standard CCFLs used by most other LCDs. LEDs are extremely energy efficient producers of extraordinarily bright light, while CCFL-style LCD televisions and Plasma televisions use more energy. For this reason, LEDs are offered as the “Eco-conscious” alternative to Plasma and traditional LCD. They are also free of harmful chemicals like mercury.
There are two technologies used in LED televisions. One is called “edge-lit”, with lights set around the television frame; the other is “full-array,” with lights set behind the screen in a grid pattern. Edge-lit models reflect light into the center of the monitor, and are the thinnest, lightest models available. Since they have fewer lights inside, edge-lit LED models are cheaper compared to full-array models. Full-arrays, however, have the best contrast ratios in LED technology.
In comparison of LCDs, LEDs produce images with greater dynamic contrast, produce less environmental pollution on disposal. LEDs have longer life span and consume lesser power than LCDs. LEDs usually cost more than LCDs.
- Samsung UN32EH4003 32-inch 720p 60Hz LED HDTV
- VIZIO E320i-A0 32-inch 720p 60Hz LED Smart HDTV
- TCL LE39FHDF3300TA 39-Inch 1080p LED HDTV
- Samsung UN32EH5300 32-Inch 1080p 60 Hz LED HDTV
- Samsung UN22F5000 22-Inch 1080p 60Hz Slim LED HDTV
An OLED TV screen uses a new display technology called OLED (Organic Light Emitting Diodes). OLED (organic light-emitting diode) is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound which emits light in response to an electric current. OLED televisions are brighter, more efficient, thinner and feature better refresh rates and contrast than either LCD or Plasma.
An OLED display works without a backlight. Thus, it can display deep black levels and can be thinner and lighter than a liquid crystal display (LCD). In low ambient light conditions such as a dark room an OLED screen can achieve a higher contrast ratio than an LCD, whether the LCD uses cold cathode fluorescent lamps or LED backlight.
As compared to LCD TVs, OLED TVs have faster refresh rate, better contrast and better color reproduction. They are very thin and lite in weight. They provide almost 180 degree of viewing angle. OLEDs consume very less power and do not contain toxic materials. In future OLEDs can be very low cost and more flexible as the OLED display can be produced on Plastic substrates.
Following OLED TVs will available in market sometime in 2013.