What is an LCD projector? LCD projectors use the same liquid display technology that can be found in electronic watches. An LCD projector creates images using a multistep process.
First, a light source produces white light, which is then passed on to dichroic mirrors. The mirrors reflect the light adding colors, and then the beam of light is fed to an LCD panel. At that point, the LCD interprets the light and projects the corresponding image onto the screen.
LCD projectors from Buydig. LCD projectors also offer better support for setups in larger rooms and home cinemas, as they are compatible with zoom lenses and lens shifts. What is a DLP projector? There is a DMD chip or digital micro-mirror device which consists of more than two million tinier mirrors. These tiny mirrors can move towards or away from the light source, to direct the light towards an image. It also consists of a spinning color wheel which delivers color and projects it on the screen.
The light source used is LED or lamp. DLP projectors from Buydig. This kind of DLP projector is mainly used in classrooms and schools and colleges. A DLP projector with three-chip architecture can deliver up to 35 trillion colors. A three-chip DLP projector uses a prism to split light from the lamp, and each primary color of light is routed to its own DLP chip, then recombined and routed out through the lens. Three-chip systems are in higher-end home theater and large venue projectors, and DLP Cinema projection systems in digital movie theaters.
This system combines three liquid crystal displays, where an image is created in a multi-step process. A light source provides a beam of white light, which is passed to three mirrors or dichroic mirrors specially shaped to reflect only a certain wavelength of light.
Here the mirrors reflect red, blue, and green wavelengths. Each colored light beam is fed to an LCD panel, which receives an electrical signal. The signal instructs the panel how to arrange the pixels in the display to create the image. The same image is created by the three LCD panels, but each with different hues due to the colored light through the panel.
The images then combine in a prism, resulting in a single image with up to Finally, the image is passed through the lens for projection onto a screen. DLP technology is 'reflective'. In a single-chip DLP projector, light from the lamp enters a reverse-fisheye, passes through a spinning color wheel, crosses underneath the main lens, and reflects off a front-surfaced mirror, where it is spread onto the DMD.
From there, light either enters the lens or is reflected off the top cover down into a light-sink to absorb unneeded light.
In LCD projectors there are always three LCD panels, and they are always light transmissive devices rather than reflective or direct view displays. Being light-source agnostic, DLP technology can effectively use a variety of light sources.
Typically, the main DLP light source is a replaceable high-pressure xenon arc lamp unit. For LCD projectors, Metal-halide lamps are used given their outputting an ideal color temperature and a broad spectrum of color.
Affordable single-chip DLP projectors typically have very little, if any, lens shift. This means that you can't adjust the height of the image without moving the projector. These units also typically have an upward throw angle, meaning the bottom of the image is at or above the top of the projector. Because of this, they have to be mounted either on the ceiling, or on a coffee table.
It's difficult, if not impossible, to place them behind a couch on a stand and still have a normal-looking image. Placing a projector in the center of the screen, vertically, is only possible with either lens shift, or no upwards throw. The vast majority of inexpensive projectors have no lens shift, and lots of upwards throw.
You also need to consider how far back you have to place the projector to create a large-enough image. Projectors have a limited zoom range, though some are greater than others. To create a specific size image, aka the size of your screen, there will be a limited range of distances that will work -- a spec typically listed as throw distance.
For inexpensive projectors, this "sweet spot" could be as narrow as a few feet. Higher-end models might be far greater. Typically these numbers, along with a distance calculator, are available on a manufacturer's website. Read more: Projector setup tips: How to get the biggest, best image for movie night.
Just like TVs, projectors have numerous features to mire you down in acronyms and marketing. Some of these features have real value, others, not so much. Automatic iris : A mechanized iris is a common feature found on both inexpensive and expensive projectors. During dark scenes, the iris closes down, making the entire image darker.
On bright scenes, it opens back up for maximum brightness. This is a bit of a cheat, as the contrast ratio at any one moment is the same and almost entirely determined by the image-creating chip or chips. However, it can make an average or poor black level, and the corresponding gray-ish shadows, less noticeable by making them, and everything else to be fair, darker during dark scenes. Some versions of this technology are slow, meaning it takes a moment for them to catch up to the video, resulting in a noticeable pulse to the brightness of the image.
If you don't find the iris's action distracting, there's no real downside to having one or using it. Not a huge benefit either, though. Dynamic lamp : Another way to achieve the same dynamic dimming of the image brightness is by reducing the power on the lamp. This has the added benefit of extending its life. Just like with the iris, on certain content you might notice the projector dimming on dark scenes. On other projectors, you might notice the fan speed ramping up and down at the same time.
Like the auto iris, this doesn't improve the native contrast ratio , as in the contrast during any single moment on screen, but it does help a bit to make darker scenes appear somewhat darker. As long as you're not bothered by it, there isn't any downside. The latter, being the easiest to understand and quantify, typically gets far too much weight when comparing projectors. Personally, I'd take a bright projector with accurate color and a great contrast ratio over a dim projector with a poor contrast ratio that happens to be 4K.
If you're super into 3D, you'll be able to find lots of options. If you're not already into 3D, I can't imagine now is the time you'd get into it. Lens shift : As mentioned above, being able to adjust the height of the image separate from the height of the projector is very handy. It allows for a wider range of placement options without having to resort to the quality-ruining potential of digital keystone adjustment. So lens shift is certainly a benefit, though if you already know exactly where your projector is going, and don't need lens shift to put a projector there, it's not a big deal.
Short throw : This isn't really a feature as much as a category of projectors. A much shorter throw distance means so you can place them closer to a screen for the same size image. For certain rooms it's very useful. The opposite would be a long throw projector, which, as you'd guess, means you can place it much farther from the screen than a typical projector.
Motorized lens : This can mean motorized focus, motorized zoom or both. Not vital, though handy. Motorized zoom, especially if you can save preset sizes, means you can fill a wider-than-normal screen for movie nights, then zoom down to just fill a portion of the same screen for TV shows. Game mode : For gamers, a mode that lowers the input lag can help tremendously.
First-person shooters, racing games, platformers, really anything that requires precise timing between button pushes and what's happening on screen. Not all game modes are made equal.
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