Home theater projectors are built for the explicit purpose of watching movies and TV. They differ from educational and office/presentation projectors because the environments differ. In an office setting, the lights are typically on, so a projector needs to be as bright as possible. In home theater setting, the lights are typically dimmed, and color authenticity is the chief concern. Unfortunately, projectors are usually not good at being exceptionally bright and exceptionally color-accurate at the same time.
In order to help you get sorted with buying the right type of projector, most manufacturers have separate product lines according to purpose. It’s hard to believe, but even they don’t try to sell you an all-in-one solution – that should tell you something about a projector’s limitations.
A good home theater projector has excellent color reproduction, and should be high definition (see the High Definition section below for more details). It should also have one or more HDMI inputs for video, along with composite video inputs for older devices.
Televisions and projectors vary greatly in their terminologies, so the term “high definition” can be a tricky one to pin down. By television standards, there are just three types of resolutions that fall under the qualifications for high definition:
- 720p – A screen resolution of 1280 pixels wide by 720 pixels high. The “p” is for progressive, meaning the entire screen is refreshed 30 times per second.
- 1080i – A screen resolution of 1920 pixels wide by 1080 pixels high. The “i” is for interlaced, meaning alternating rows are refreshed (even rows, then odd rows, then even rows, etc.), each at 30 times per second.
- 1080p – A screen resolution of 1920 pixels wide by 1080 pixels high. The entire screen is refreshed 60 times per second.
That final resolution, 1080p, has become the de facto standard, and anything lower is generally considered to be a “lesser” television. All high definition televisions are in the 16:9 aspect ratio. If you happen to be watching an older, standard definition program in the narrower 4:3 resolution, the screen will be “letterboxed,” meaning black bars will appear on the unused portions of the screen.
Projectors come in a much wider variety of resolutions, and many of them claim to be high definition. Technically, any projector that matches or exceeds a resolution of 1280 × 720 can be called high definition. Higher resolutions will generally offer more sharpness, but do not expect a perfectly arithmetic increase in quality. Factors like display technology, brightness, color reproduction, refresh rate, and projection surface have significant impacts on picture quality. Below is a partial list of projector resolutions (and their aspect ratios) that meet this criterion:
- 720p – 1280 × 720 (16:9)
- WXGA – 1280 × 768 (5:3)
- WXGA – 1280 × 800 (16:10)
- SXGA – 1280 × 1024 (5:4)
- SXGA+ – 1400 × 1050 (4:3)
- UXGA – 1600 × 1200 (4:3)
- 1080p – 1920 × 1080 (16:9)
- WUXGA – 1920 × 1200 (16:10)
- 2K – 2048 × 1080 (17:9)
- QXGA – 2048 × 1536 (4:3)
- WQXGA – 2560 × 1600 (16:10)
- QSXGA – 2560 × 2048 (5:4)
When using a projector to watch high definition programming, the screen will typically letterbox the unused portion of the screen, like a television.