With anything in technology and electronics, there is one constant. Technology is always changing, most often for the better. For gadget geeks, that can mean hours of pouring over tech specs and user reviews. For the average electronics consumer, it tends to cause more confusion than good. As far as projectors and rear projection tv’s go, the latest and greatest in technology is best reflected in the open competition between three technological advances, DLP, 3LCD, and LCoS.

DLP, or digital light processing: In DLP projectors, the image is created by microscopically small mirrors laid out in a matrix on a semiconductor chip. Each mirror represents one or more pixels in the projected image. These mirrors can be repositioned rapidly to reflect light directly through the lens. Colors are either produced by placing a spinning color wheel between the light source and the micro-chip or by using individual light sources to produce the primary colors.

3LCD or 3 Liquid Crystal Display: In short, 3LCD is a sophisticated technology that utilizes 3-chips to deliver color. The light source projects white light onto a combination of mirrors that split the light into its three basic video colors. Each of the three LCD chips take the electrical signal they receive and creates the image. The three color images are combined using a prism to form a full-color image consisting of millions of colors. The singular, full-color image passes through a lens and is projected onto a screen.

LCoS or Liquid Crystal ove Silicon: LCoS is a “micro-projection” or “micro-display” technology typically applied in projection televisions. It is a reflective technology similar to DLP projectors; however, it uses liquid crystals instead of individual mirrors. By way of comparison, 3LCD projectors use transmissive LCD chips, allowing light to pass through the liquid crystal. In LCoS, liquid crystals are applied directly to the surface of a silicon chip coated with an aluminized layer, with some type of passivation layer, which is highly reflective. Thus, the light source reflects off of the silicon chip as opposed to being passed through the liquid crystals.

As is the case with any technology. there are advantages and disadvantages in the three examples here. Picture quality, projector or tv size, and cost are all considerations one should make before choosing any of these three. Armed with these explanation, one can most certainly make a well informed choice.

There are a lot of ways to enhance the experience of a home theater, but few consider the things that will keep your projector operating at the optimum level. The projector is not like a lawn mower, it won’t need an oil change, or need the ever-elusive oil/fuel mix. You won’t need to change strings like on your weed whacker, or rotate the tires. Fortunately, every common maintenance consideration you will have for a projector is simple, and easy to do.

The first tip for basic upkeep of the projcetor is to keep a fresh lamp inside. The light source is maybe the most important part of a projector,…no light, no picture! There are ways to tell how long your lamp has been used, like the lamp life counter found on most projectors. Be sure to reset the counter when you change the lamp. If your lamp is rated for say 3000 hrs of use, when the counter gets about 1500 hrs, start shopping for a new replacement lamp. Not all projectors have a lamp life counter, so think about keeping a log, or write down the dates the lamp was changed. You can get fairly accurate in predicting how long your lamp has left if you know how much you use the projector, and the time since the last lamp change.

While changing your lamp, it is the perfect time to clean the filters that are inside the projector. Doing this will eliminate the possibility of the filter being clogged with excess dust, thus causing the projector to overheat. If the projector overheats, it could cause the lamp to burn out early, or even explode. Also, be sure to check the lens for excess dust or fingerprints. Use a cleaning cloth that does not scratch the lens as you clean it. Thes tips should help maintain your projector, and ensure that it projects the best images possible.

Aspect ratio is one of the most important considerations in your home theater.
The aspect ratio is the ratio of video image’s width to its height. Standard television screens are 4:3; this means that the video is four units wide for every three units of height. Another way to refer to the 4:3 format is by the numeric value 1.33 (4 divided by 3). The picture can then be thought of as having 1.33 units of width for each unit of height.

All standard television programs today are broadcast in 4:3. Most older classic movies were also filmed in 4:3. Today’s movies, however, are produced in widescreen formats. There are several widescreen formats. The back cover of most DVDs will tell you the aspect ratio. It usually won’t be 4:33 (1.33). The most common is 2.35. This means that for each unit of image height, the picture will be 2.35 units in width.

A movie with a 2.35 aspect ratio won’t fit on a 4:3 (1.33) screen without compromising. There are two ways to work around this. The first is to simply show the movie in its original aspect ratio. This shows you the movie the way it was filmed but, unfortunately, the picture will look smaller because you will only use a portion of the television’s 4:3 display area. The other option is to use the “pan and scan” feature but this will cut off some of the original film in order to fill the entire 4:33 screen.

So! You want to know the real difference in the top of the pile video formats? Well, that’s what this little slice of wisdom is hopefully going to do. When it comes to these kinds of things, we know what we’re talking about. No, really - we do. Without further ado, here’s how it all started:

Back in the good old days of the late 1960s, there started in Japan a newfangled theory that television broadcasts could look better than the crummy old sets we’d all been using since the early days of color television. Improvements had been made - color reproduction, contrast, sharpness were all greatly improved by the introduction of high quality digital components that were simply better than their old analog counterparts. But that hadn’t changed the fact that the CRT (cathode ray tube) hadn’t really changed all that much. At the same time, it was well established that a higher quality picture tube was quite feasible. Some bright scientist somewhere said “HEY! What if we made a television that could do the same thing as a computer monitor?” And so, the quest for high definition television was begun.

Experiments with HDTV had been tried before - England and France had both experimented with higher definition broadcasts in the 1940s, Japan had tried in the 1960s and 1970s, and all of them eventually abandoned the idea. The experiment was lackluster at best and an outright failure at worst. Because high definition uses more bandwidth than a normal broadcast, there’s a sacrifice - you can have either high quality visuals OR lots of channels in over the air broadcasts…but not both. There was, however, some good. By the early 1980s, standards such as the formats that would later become standard HDTV were agreed upon. With the advent of digital broadcasting in the form of satellite and cable services, the early fears of broadcast limitations were more or less dissolved. Digital signals have a much higher capacity allowing TV watchers to have their cake and eat it, too. In addition, public interest was becoming sparked by the prospects of a higher quality television.

Around 1997, the first 480p/720p televisions went on sale to the general public in the USA. Though extremely expensive at first, these first generation TVs made a great impression based on their high quality picture. During this period, there was also an influx of EDTV sets, which were able to display at 480p only. These sets have largely been phased out in favor of newer 720p/1080i capable screens, but they are still occasionally seen in second hand stores, yard sales, and online.

The main problem was the fact that at first, there was nothing to use with the new HDTV screens! High definition broadcasting was an entirely new concept in the USA, and although DVD players have higher quality images than VHS tapes, the max resolution of a DVD player is only 800 pixels by 600. You could get an up scaling DVD player, but they were pricey. As if that weren’t frustrating enough, there was also a vigorous debate over how to get the best quality of signal out of the attached devices - analog connections or digital. The benefits and disadvantages of these could fill their own article (hint, hint..) but the basic argument boils down to the fact that digital doesn’t lose signal quality and analog is much cheaper to use.

These days, with the introduction of the new (and pricey) 1080p screens and truly high definition formats such as Blu-Ray and HD-DVD, the high definition television has come into its own. It’s now possible to get a high quality high definition screen for around $800-$1000, or a similar quality projector that can output an extremely large image (typically, 100”+). The issues initially encountered are now far removed, and in many cases outright eliminated.