วันพฤหัสบดีที่ 14 มกราคม พ.ศ. 2553

HDTV For the UnGeek

The FCC's standard for HDTV transmission is with a large effect. The amount of information to be digested can be daunting, even for professionals. The old hardware does not become obsolete, but it will need a tuner to convert from the new signal, if you get the signal from a VHF / UHF antenna. If you have cable or satellite TV, which will be provided by the service provider.

However, this might be a good time to upgrade your hardware. The new standard offersa much better picture. In the current world of digital projectors, LCD, LCoS, plasma and DLP are the four different types of TVs that dominate the HDTV market. Each has unique advantages over the others. Plasma and some LCD screens can be mounted on the wall, even though surveys find that some people do they mount on the wall. DLP and LCOS and LCD displays are some of both projector technologies. Rear projector units are usually very inexpensive. The size of some Systems is now less than 12 centimeters in depth.

• Video quality on the best projectors now surpasses that in a conventional commercial cinema.

Plant types:

• Traditional TV: as a direct point of view, the images displayed on a CRT (Cathode Ray Tube).
LCD (Liquid Crystal Display) and plasma TVs can also direct vision. The LCD and plasma TV systems are "flat-panel units.
• Rear Projection> TV (RPTV): uses a combination of mirrors and lenses to focus the image onto the screen from behind project. This allows the displayed image to be significantly larger, up to 70 inches or more. This technique usually offers the best value (size vs. cost).
Front-Projection TV (FPTV): this is like a cinema. The image is being projected forward to an external monitor. But as a movie theater is a very dark room needed because the screen will reflect any lightinto the room. This technique is generally more expensive than rear-projection, but the footprint (the area consumed by the device) of the system is smaller.


CRT (cathode ray tube):

The established standard for TV displays, good price, image quality. The maximum size of the screen is smaller with technology. The technology is still a good choice when you want a smaller picture, and bulkiness is not relevant.

LiquidCrystal Display (LCD):

Thin design, but has problems, the display of images in motion (sports), tilt the images that appear on strips. These projectors usually contain three separate LCD glass panels, one for red, green and blue, which is projected. Since the non-colored light through the LCD panel, the individual picture elements (pixels) to be opened to let the light, or closed, blocking the light. This creates the image on the projectedScreen.

Historically, LCD devices have had a problem with visible pixilation. This is less evident on newer devices with higher resolutions.

Most LCD systems use a fluorescent backlight to shine through the LCD screen. This type of lighting will need to be replaced every few years. Some manufacturers are introducing LED-backlit display, with a 10-fold longer lifespan. Although the initial cost may be more the cost of ownership can take advantage of this design worthLook.

• Better color saturation, more rich and vibrant
• Better sharper image, important for the text
• Increased energy efficiency

• Poor black level and contrast
• Problems displaying images in motion (Sports)
• may lower LCD panels (mainly in the blue channel), leading to shifts in the color balance
• Visible pixelation

Liquid Crystal on Silicon (LCoS):

A type of LCD technology, LCOS uses liquid crystals asMirrors (usually back-projection), an image projected on the screen. LCOS is a good value compared to plasma and LCD sets, but expensive compared to other rear-projection TV technologies such as DLP. This technique uses a chip such as a DLP (see below) is set, but the chip is coated with liquid crystals, reflects the image seen on the screen. LCOS-based systems provide higher resolution than an LCD display or plasma display.

• Sharp, vividColors and deep blacks
• It is slowly changing with the times, like a plasma can be considered

• Dead pixels occur in the rule, because the technique is partially reflective
• High Maintenance Cost: LCOS requires frequent bulb changing needs (somewhere between 6000 to 8000 hours, about 3-4 years with normal use), compared with 50,000 or more for most LCD or plasma screens. A replacement lamp costs about $ 400
• Repeatability: The picture quality can vary greatly fromMachine to machine

Digital Light Processor (DLP):

The DLP Texas Instruments is a product that is manufactured in Korea. It uses a chip can (with many levels for more than one million mirrors on a chip of about one square centimeter), which can be mechanically controlled in order to reflect the correct color. This technology provides excellent display, at a moderate price.

In the best DLP projectors, like the ones in use at your local cinema, there are three different levels-chipseach for red, green and blue channel. However, to be marketed in the DLP projectors for the masses, there is only a single chip. In these sets, define the color, there is a color wheel that consists of red, green and blue filters. The wheel spins between the lamp and the DLP chip and alternates the color of the light hits the chip.

The spinning color wheel used to rotate the image, which can be a problem on the screen as the rainbow effect, which produce the colors separated in different red-known project toGreen and blue. At a certain point, the image on the screen either red or green or blue, and the technique relies on the eyes, not in a position to recognize the rapid changes from one to another. However, not only some people can see, separate the colors, but the rapid succession of color may be responsible for the reported cases of eyestrain and headaches. But the vast majority of the people can not see the rainbow effect.

Newer sets have the color wheel speeddoubled. Even the newer sets instead of using a six-segment color wheel (of a 3-segment), which is two sequences of red, green and blue. Because the wheel at double speed, and because the red, green and blue seen twice in each rotation, the effect of a fourfold increase in speed. This eliminates the visibility of rainbows for the majority of people who have previously seen, the effect.

Samsung and other companies have introduced DLP sets with LED lamps and no color wheel. The bulbsneed to be replaced in the older designs every few years. The LED bulb should be over the lifetime of television.

LaserVue (Mitsubishi) is introduced in the United States now in time for the Christmas season. LaserVue is a DLP system (Texas Instruments' Dark Chip 4 "Digital Light Processor) that the standard bulb removed and replaced with a solid-state lasers. The performance of the video is excellent, but the technology will cost about $ 7000 for a 65 "HDTV.The reliability / lifetime improvement can be better, but there is little data about this new laser system. An argon ion laser would be expected to have a lifespan of approximately 8000 hours (5-6 years) of normal use. The Mitsubishi LaserVue uses a laser system of Arasor, an Australian start-ups, made of lithium niobate (PPKN). Mitsubishi currently occurs accelerated stress test, but has not published any results. An HDTV LaserVue draws under 200 watts of electricity. This isabout half of the comparable LCD HDTV, and less than one third of a plasma-high-def system.

• Small package size
• High contrast image with deep black levels
• Good value --

• Less bright images
• Rainbow Effect
• High Maintenance Cost: DLP requires frequent bulb changing needs (somewhere between 6000 to 8000 hours, about 3-4 years with normal use), compared with 50,000 or more for most LCD or plasma screens. AReplacement lamp costs about $ 300 - $ 400 Samsung is equipped with LED lighting instead of lighting. The LED should not be replaced.

Plasma Display:

Thin-design, high contrast ratings, size up to 60 inches or more, some display limitations: expensive, older systems have a high burn-in risk (over time, a reminder of that projected what was retained); This could be a problem for those who play video games or movies, such as adhesive tape. If one game or tape on pause for toolong, this could be an image on your screen.

• Exceptional picture quality: It can store up to 8.6 billion colors, accurate color reproduction and wide viewing angles
• Large screen sizes: Some Plasma TVs are now produced the range in screen sizes, up to 100 cm
• Lifetime: Plasma TVs are known for their extended service life capacity of about 60,000 hours and good contrast (deep blacks)
• less expensive thanLCD

• The displays are very bulky, heavy and fragile
• Burn-in
• Slowly increase over time
• Energy efficient

Coming Soon: OLED (Organic Light Emitting Diode) HDTV devices are now available, but it will be a few years before they warrant serious consideration. An OLED is set less than 1 mm thick. OLED is already used in digital cameras and mobile phones with small plates, due to their energy efficiency, which is important inportable devices.


• NTSC analog TV or standard definition TV (SDTV) is: The current system, which could have arisen vote (National Television Systems Committee).
• EDTV (Enhanced Digital TV): In fact, high-end standard-definition TV: While these rates may be better than standard sets, the image quality is not equal HDTV. Technically, there is little difference between an SDTV and HDTV ( ) except for the higher price.
• ATSC Digital TV: This is the new system (Advanced Television Systems Committee), which is not necessarily high definition.
HDTV: digital TV is where the image is a widescreen picture, often with more detail than is contained in current analog TV pictures. Most consumers will see a huge improvement in picture quality. HDTV has better picture quality than SDTV, because a greater number of lines of resolution. The image is two tofive times sharper because the gaps between scanning lines narrower.


Each of the four technologies can be a good choice. The competition is intense, and all the technologies will continue to improve. The purchase of a TV will never be as easy as it was before HDTV, but the benefits can be the value of a headache.

Visit : HDTV TVs Reviews