Video Projectors

Definition

Although video projectors are more commonly seen in the business world for presentations and the educational world for lectures, there is growing interest in the use of video projectors in home theater setups. Video projectors are considered the superior choice for home theaters due to their ability to play media in different locations as long as a screen is present. They are also valued for their ability to create a video screen vastly larger than what is possible with a traditional television.

Though there are multiple Internet sites claiming that a "do-it-yourself" video projector is possible, thanks to a growing consumer base for these products, it is best to research and comparison shop instead of risking money on parts.

Choosing Your Projector

Type

The most common types of video projectors are LCD and DLP. LCD stands for "liquid crystal display." The system is the simplest of projector systems, similar to a slide projector. The system can open and close pixels in the three color panels, which are the familiar red, green and blue of traditional television. This lets the LCD system display a vast range of colors and shades. The drawback is that, because the system relies on open and closed cells, the projected image can appear pixelated or blocky. The DLP (Digital Light Processing) system uses a matrix of micromirrors as pixels, which can direct light either towards the viewing screen or into a light sink. Colors are achieved by shining light through a rapidly rotating color wheel or by using individual lights like LEDs. Be careful when looking at a DLP system that uses a wheel: Some consumers experience a "rainbow effect" when moving their eyes while watching an image. Most newer models have eliminated this problem.

Video Resolution

Resolution for projection systems can range from 800x600 pixels all the way up to 1920×1080 pixels. The highest resolution, considered "HD," is becoming more useful as programming and videos are available in higher resolution formats. However, cost goes up with resolution, so it is not always necessary to invest in the highest level. Video quality and cost also depend on its light output: This can range from 1500 to over 4000 lumens. Brighter lights are necessary for larger screens and viewing areas with more ambient light. 

Input Connectivity

Standard inputs for projectors include HDMI, VGA, component video, composite video and PC I/O. Most models allow multiple input sources. It is best to opt for a projector with multiple HDMI (High-Definition Multimedia Interface) connections, as HDMI is used for a multitude of video sources including DVD players, Blu-ray players, the PlayStation 3, Xbox 360, Wii U and many tablets. Ensuring that a projector can accommodate multiple sources of HDMI allows for use of most popular devices without switching cables.

Usage Differences

Video projectors can be used in the home, a business or in the classroom although their high cost makes them a rare educational tool. Business use for video projectors is generally limited to presentations, which may be a series of images and graphics rather than one continuous video. Because of this, video quality is less important. While specialized firms may require notably crisp images and smooth frames, the average business presentation will not. Business use is also more limited in time. While home use can reach into hours per day, an office video projector is unlikely to be used so heavily. For this reason, expensive replacement bulbs and wear concerns are less applicable to a business video projector. Consumers looking to create a home theater experience will also need to consider throw ratio, which relates the size of the projected image to the projector's distance from the screen. Those wanting a larger display size will either need to move the projector farther away from the screen or find a projector with a lower throw ratio.

Noise Level

If noise is a concern, opt for one of the LCD models. LCD and DLP models both have fan noise that averages around 30 dB, but older DLP models that use a moving color wheel can have a significantly louder level of operation. Remember that 30 dB is the equivalent to a whisper, from six feet away, in a quiet room. Most models are marked with a fan noise, so as long as the number does not reach 60 dB, which is equivalent to a normal conversation, fan noise is negligible.

Lens Shift

Lens shift and digital keystone correction are the types of tools available for a consumer to shift or move the projected image. However, digital keystone correction changes the pixels of the image that is projected and can lead to distortions that are especially noticeable when watching videos. Lens shift is when the lens physically moves within the projector housing. Most models will be able to shift their lens vertically, but more expensive models can move the lens horizontally or even diagonally. If a video projector is going to be stationary, these adjustments are not as necessary. But if the projector is intended for multiple viewing locations, or if space is a concern, then lens shift allows a video projector to be more versatile. 

3D

There are already many models available that are 3D-compatible. Both LCD and DLP types can support 3D, though older LCD models could not. However, most Blu-ray DVD players use the HDMI 4.1a video mode. Unless a model specifies that it accepts this specific input mode, a converter box is needed to connect the DVD player to the projector. As the 3D video format becomes more popular, more projectors will not need a converter.

Which Projector for Which Use?

For business use, the most basic video projector will suffice. Extras like lens shift and 3D compatibility are not needed for most basic presentations. It is best to find a simple model with low power consumption and multiple input types.

If the video projector is intended for home theater use, extra features are usually worth it. Lens shift ability and multiple inputs make setup easy, and 3D compatibility is a must nowadays. Look for a projector with a quiet fan and a bright light. And for the best video quality, make sure that the theater setup is optimized for a projector by creating a dark room that can provide enough space for your desired screen size.