Choosing the right projector is as simple as knowing what you will be using it for. Whether you're interested in sharing business presentations on the road or upgrading your home theater system, we'll help you find a great, high-quality, cost-effective solution.
What types of projectors are available?
Overhead Projectors Overhead projectors use traditional lamp bulbs to project an image. Their image quality is primarily determined by the type of lens they use: singlet (the most basic and least expensive), doublet or triplet (the most advanced and most expensive). There are two types of overhead projectors: transmissive and reflective.
Transmissive Projectors
A transmissive projector's light source is contained within its base. It projects light upwards through the transparent image (which sits on a glass "stage") to a lens on the top ("head") of the unit and out onto the projection screen. Transmissive projectors work well with printed film transparencies or an LCD panel computer display. They provide bright, sharp images but tend to be very large and heavy, often requiring a cart to wheel them between rooms.
Reflective Projectors
A reflective projector's light source is contained in the top ("head") of the unit. The light is projected down onto a reflective tray which bounces the light back up through the lens and out onto the projection screen. Reflective projectors are smaller, lighter and more portable than transmissive projectors, but their images are rarely as sharp or bright and they only work well with printed film transparencies.
Slide Projectors Slide projectors work by bouncing light off of a reflector, through a transparent film slide and an image-focusing ring, and out onto the projection screen. Slide projectors often come with automated slide-changing mechanisms (either rotating carousels or linear trays), which are ideal for viewing slideshows of 35mm or 2" x 2" photographic slides. Few manufacturers produce slide projectors any more, so finding a new one may be difficult.
Multimedia Projectors You can use a multimedia projector to project images from many different sources, like your DVD player or your laptop computer. Multimedia projectors can produce fantastic video quality and many people are replacing their TV sets with a projector and screen for the ultimate home theater experience. Multimedia projectors come in three types: CRT, LCD and DLP.
CRT Projectors
CRT (Cathode Ray Tube) projectors produce an image comprised of red, green and blue light. They project crisp images at any resolution with a full range of colors and the blackest blacks.
Pros: CRT projectors create the most authentic cinematic movie experience of all multimedia projectors.
Cons: Cost - CRT projectors cost nearly double the price of LCD and DLP projectors. CRT projections need to be viewed in very dark rooms because ambient light will wash out the image. They're large, bulky and difficult to move between rooms. Also, they can be expensive to maintain - if one of the color tubes fails, all three have to be replaced.
LCD Projectors
LCD (Liquid Crystal Display) projectors create an image by projecting light through small, transparent LCD panels. They're much smaller and more portable than CRT projectors, which makes them perfect for home or office use. If you want to use your projector for home theater, be sure to shop for an LCD projector that is designated specifically for home theater use. Less expensive office models tend to have lower resolutions.
Pros: Price - LCD projectors cost a fraction of the price of a CRT projector. LCD projectors produce good colors and high contrast for great image quality even in partially lit rooms. They're compact and lightweight making them very portable, and they consume very little power.
Cons: LCD projectors project light through tiny pixels onto a big screen, and the image can sometimes look pixilated or blocky. This is referred to as "the screen door effect" because the image looks like you're viewing it through a screen door. If a pixel burns out it will display as a black or white dot on the screen and the only way to fix this is to replace the whole chip. The image resolution of an LCD Projector is limited by the amount of pixels on its chip. If your projector only has a 1024x768 resolution chip and you're watching high definition television (HDTV), the image won't be as sharp and detailed as it would be from a CRT projector. Also, fan noise can be a noticeable distraction depending on the placement of the projector in the room and the light source needs to be replaced about every 1,000 to 2,000 hours of use.
DLP Projectors
DLP (Digital Light Processing) projectors create an image by projecting light through a transparent chip onto a minute mirror array, resulting in high quality, high definition images. They're great for office or home theater use and they don't suffer from "screen door effect" like LCD projectors.
Pros: Price - DLP projectors cost a fraction of the cost of a CRT projector, though they're still slightly more expensive than LCD projectors. They use very little energy and produce very high quality images with vivid colors and high contrast, even in partially lit rooms. They're more durable than LCD projectors and don't suffer from "screen door effect".
Cons: DLP projectors suffer from having a fixed resolution like LCD projectors. Their light source must be changed every 1,000 hours or so to keep the image bright and sharp. Also, while this is rare, some DLP viewers see a brief flash of colors (often called a "rainbow effect") when they look rapidly from one side of the screen to the other.
What will you use your projector for?
Home Theater Looking to upgrade your home theater viewing experience? Consider a portable LCD projector. They're a convenient and cost-effective alternative to traditional big screen TVs and you can easily carry one around the house. Keep in mind that most projectors don't have built-in audio so you'll need to buy separate speakers to compliment your home theater setup.
If you receive high definition TV programming through your cable or satellite service, shop for a projector that's HDTV compatible. If you're a frequent TV or movie watcher, consider shopping for a DLP projector instead. They're a little more expensive, but they deliver the best digital video quality available.
Here are a few basic requirements to look for when shopping for your home theater projector:
Projector Type: LCD
Native Resolution: XGA 1024 x 768
Maximum Resolution: UXGA 1600 X 1200
Brightness: 2000 lumens
HDTV Projector: HD Ready
Aspect Ratio(s): 4:3, 16:9
Projection Distance: 3 - 35 ft
Contrast Ratio: 400:1
Horizontal Frequency: 15 - 91 KHz
Price: Starting around $800
Business Presentations DLP projectors are great for multimedia (text, graphics and video) presentations. If you'll be giving presentations on the go, portability will be one of your biggest concerns when choosing a projector. Shop for a unit with built-in audio and a remote control. Make sure it's lightweight (3 to 8 lbs) since you'll probably also be lugging around a carrying case and cables.
Most multimedia projectors are plug and play, but check to be sure that the model you're considering will work with your PC's operating system. Some projectors aren't Mac-compatible or may require additional software to work with your Mac.
Here are a few basic requirements to look for when shopping for your multimedia business projector:
Projector Type: DLP
Native Resolution: XGA 1024 x 768
Maximum Resolution: UXGA 1600 X 1200
Brightness: 2000 lumens
HDTV Projector: HD Ready
Aspect Ratio: 4:3
Projection Distance: 4 - 24 ft
Contrast Ratio: 2000:1
Horizontal Frequency: 15 - 80 KHz
Price: Starting around $1,500
Instructing A Class If you're teaching a class, consider an overhead or slide projector. Both are long lasting and reliable. Overhead projectors work well with printed transparencies or LCD panels and slide projectors work best with 35 mm or 2"x2" film slides. If you're presenting a slide show, shop for a slide projector with a removable automated slide carousel or tray and a wireless or infrared remote control.
Projector Type: Slide Projector
Price: Starting around $230
Important Terms
Aspect Ratio Aspect ratio refers to the width vs. the height of the projected image.
4:3 Aspect Ratio
(4 units wide by 3 units high) is the standard for projectors. UXGA, VGA, XGA, and SVGA resolution all have a 4:3 aspect ratio.
5:4 Aspect Ratio
Images with SXGA resolution have a 5:4 aspect ratio.
16:9 Aspect Ratio
Widescreen images have a 16:9 aspect ratio. This aspect ratio is wider than the standard image produced by most projectors and is a common format for DVD and HDTV signals.
Brightness A projector's brightness is measured in lumens. Generally speaking, if you want to project your images in a brightly lit room you should shop for a projector with a minimum of 3000 to 12000 lumens.
Contrast Ratio Contrast ratio is the ratio between the darkest and brightest areas of the projected image.
Low Contrast
The contrast ratio of low contrast projectors is less than 500:1.
Medium Contrast
Medium contrast ratio projectors can be found with a ratio of 500:1 to 1200:1.
High Contrast
High contrast projectors will have a ratio greater than 1200:1.
Data Signal Ports The data signal ports on your projector are where you plug in the cables that connect your projector to its image source (like a laptop computer or a DVD player). Make sure they're compatible with whatever image source you'll be pairing them with. Some image sources may require an adapter.
Keystone Correction Keystone correction is the ability to correct the image distortion that is created when a projector is placed at anything other than a 90 degree angle to the screen.
Native resolution Native resolution for a digital projector is the actual number of physical pixels on the projector's image chip. To get the best image quality, find out the resolution of your image source (laptop computer, DVD player, etc.) and shop for a digital projector with a matching native resolution.
Screens Projection screens come in various fabrics and sizes. While it's certainly possible for you to project your images onto a blank wall, you'll get the best image quality by projecting your images onto a good screen.
Video Format Capability A digital projector's video format capability determines which video format data it can accept. Most projectors will offer all three: PAL, NTSC, and SECAM.
