It used to be that selecting a big-screen simply meant buying the biggest TV that could fit through your front door. Now there are many choices, allowing you to choose the video display that’s right for your style and tastes, that looks great and that works well with your home theater space. The downside of having all these options available is that it’s hard to know what to look for among the multitude of TVs, projectors and other devices staring at you from retail shelves, advertising flyers and magazines.
Fret no more. There are basically four types of video displays: traditional direct-view TVs, front projectors, rear-projection sets and flat-panel displays. There’s also a slew of technologies and features, though we can deal with that subject later.
1. If you’re planning a dedicated theater room with a really big screen and enjoy watching movies in the dark, then a front-projection display system may be best for you. These use a projector that shines an image on a screen. Just beware that light from windows and room fixtures can wash out many front-projection images.
2. The most popular projectors today use DLP (digital light processing) technology, but there’s also CRT (cathode ray tube), LCD (liquid crystal display) and LCoS (liquid crystal on silicon).
3. Front projectors can be ceiling mounted or floorstanding. Many of today’s lightweight models (DLP, LCD and LCoS) hang unobtrusively from ceilings and can even be toted around for use outside of the home theater.
4. You’ll need enough space from the front of the room to the back for a projector to “throw” a large image onto a screen. Some projection manufacturers’ web sites have a throw-distance calculator to help you determine how much room you’ll need. Be sure to consult a custom electronics professional as well.
5. If you want a screen up to 80 inches in size, have light coming into the room or watch TV and movies with the lights on, then a rear-projection TV or monitor may be right for you. These units traditionally have been huge in size, and rear projectors that use CRTs are still quite large. However, if you have the space, CRT rear-projection sets offer smooth pictures and appealing price tags, especially for HDTV.
6. There are now several attractive options in rear-projection sets. Newer displays that use DLP, LCD or LCoS have reduced the cabinet depth to 16 inches or less and are far lighter than the CRT displays.
7. Newer rear-projection sets of all types have high resolutions and superior brightness. And you no longer have to sit 10 to 15 feet from the screen to get a picture that’s free of scan lines.
8. If you have a room with a lot of light and are on a budget, a traditional direct-view TV may be the ticket. Don’t scoff: With their big cathode ray tubes, direct-view TVs still offer the best filmlike picture of all the display technologies. And they remain the most affordable.
9. Don’t settle for the same-old analog direct-view TV. Spend a few hundred dollars extra, and get a digital TV—preferably an HDTV. Digital TV has arrived, and it will likely be the standard by the end of the decade. (See “The Big Picture of HDTV,” page 66.)
10. For HDTV, models with 27-, 32- and 36-inch screens normally come with a traditional squarish 4:3 aspect ratio, while those with 26-, 30- and 34-inch screens are offered in the more rectangular widescreen format (16:9 aspect ratio).
11. If you have some light in the room but don’t want your set taking up space, then today’s sleek and sexy flat-panel TVs and monitors can satisfy. Plasma-based, LCD and LCoS flat panels are only 3 to 4 inches thick and can hang from walls.
12. Plasma-based monitors generally have screens that measure from 42 to 60 inches diagonally, though bigger ones are making their way to the market. LCD flat panels aren’t quite as big yet, but a couple of larger ones have broken the 45-inch barrier. Some large LCoS-type flat panels are also available.
13. Look for flat-panel sets with high brightness levels and great contrast ratios. Greater brightness means the screen can be viewed in more brightly lit rooms, and higher contrast translates to deeper blacks.
14. If you want to keep the wires hidden, expect to punch a hole in the wall behind a flat-panel screen to route the video and power cables, or look for a stand that can hide the cables.
The Technologies Explained
15. CRT (cathode ray tube) is the oldest, most proven video technology available today. It’s available in front projectors and rear-projection TVs, and it’s what our big, bulky traditional TVs use. Those TVs have one large tube that throws an image onto the screen. CRT front and rear projectors have three tubes, or guns, each. It’s still the technology for noncompromising videophiles.
16. DLP (digital light processing) works when thousands of tiny mirrors on a small computer chip change position to reflect light. It has become the most popular front-projection technology, and it is now available in rear-projection TVs as well. One-chip front projectors spin a color wheel in front of the light to produce the bright and colorful images we see, while more expensive three-chip projectors use three chips to produce red, green and blue and the millions of color combinations they create. The bright images created make it possible to view the picture without completely dimming a room’s light.
17. LCD (liquid crystal display) has a backlight that shines through a panel made up of liquid crystal cells. Though it is mostly used in flat-panel and computer displays, LCD is also available in front projectors. LCD technology has improved greatly in the past few years and is now available in bigger displays that are suitable for home theater. They are also a great choice for kitchens, patios and offices.
18. LCoS (liquid crystal on silicon) front and rear projectors can produce smooth and bright images, combining some of the best attributes of LCD and DLP technology. Variations of LCoS include JVC’s D-ILA (direct image light amplifier) and HD-ILA and Sony’s SXRD (Silicon Xtal [crystal] Reflective Display). Keep an eye on this emerging technology.
19. Plasma-based displays function when individual pixels are illuminated by gases that are excited by an electrical charge and glow. Because these displays don’t require a large tube firing from behind, their chassis can be as thin as three to four inches and hung from walls. They’re a great choice to hang in family rooms and bedrooms and even over fireplaces.
If you’re getting a front-projection system, what about the screen? For one thing, not all screens are the same.
20. Front-projection screens are either affixed permanently to a wall or frame or motorized to roll down from the ceiling and roll back up when not in use. Some screen manufacturers offer masking systems that alter the shape of the viewing surface, or aspect ratio.
21. There are four common aspect ratio sizes, or shapes to a screen: 1.33 (traditional TV), 1.78 (widescreen HDTV), 1.85 (letterbox video) and 2.35 (CinemaScope).
22. One important performance factor is called “gain.” This is a relative measure of a screen’s reflectivity and relates to the perceived brightness. A 2.00-gain screen reflects back more light than a 1.00-gain screen. The higher the gain, however, the narrower the viewing angle. Choose a screen with a gain of 1.3 or less to ensure that your movies look top-notch.
23. Acoustically transparent or “perforated” screens have tiny holes in the viewing area that allow speakers to be placed behind them and sound to come through with only a small compromise in audio and video quality.
24. A variety of materials are used for screen surfaces. Before selecting a screen, you should first consider the projector type and model, viewing angles, ambient light conditions, seating layout and screen size.
25. A gray screen helps to enhance black levels of DLP and LCD projectors. There is even a new black-screen technology that allows viewers of front video projectors to watch movies in less-than-darkened rooms by reflecting only the light from the video projector.
26. Screens can also be certified by THX and ISF (Imaging Science Foundation). Check with your local electronics dealer to determine the most appropriate screen for your home theater.
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