Choosing an LCD Projector Company
Whether you’re looking for a portable projector for presentations or a 1080p business/education workhorse for permanent installation, you can expect rich color saturation and image sharpness from LCD-based models.
Unlike DLP, LCoS models can support native 4K content. These models use pixel shifting to double the number of pixels projected onto the screen from their native 1080p imagers.
History
Whether you’re watching a business presentation or settling in for a home movie night, chances are you’re viewing an image projected on a LCD (Liquid Crystal Display) projector screen. In spite of their relatively recent introduction, these projectors have already made significant inroads into the market and are poised to replace older projection technologies.
The technology behind an LCD projector is a bit more complicated than a standard overhead projector. First patented in 1888, the technology was used in wristwatches and calculators lcd projector wholesale before being adopted for use in computer monitors. Eventually, LCD screens were developed that were much smaller and more efficient than the old overhead projectors, with some companies even producing portable models.
New York inventor Gene Dolgoff began working on the LCD projector concept in 1968 as a means of creating brighter, more modern video projection devices than the then-available 3-CRT projectors. He settled on the idea of using liquid crystals to modulate light in 1971, but it took him until 1984 to develop a digitally-addressable LCD matrix device with enough resolution and contrast to create a projector.
The first LCD projects used a single backlit LCD panel that had to be manually adjusted for each frame of video. In more recent times, however, LCD and DLP projectors have employed lasers and Light Emitting Diodes to separate white light into red, green and blue beams which are then directed onto dedicated RGB LCD or DMD micro-mirror arrays where they are recombined into an aligned beam of full-color video.
Technology
When shopping for a new projector, there are several different technologies to consider. LCD (“Liquid Crystal Display”) is one of the most popular choices among consumers, schools and businesses due to its rich color saturation and sharp image projection. Most models in the category utilize three LCD panels that reflect red, green and blue wavelengths of light after receiving an electrical signal. The result is a single image made up of 16.7 million colors that are then combined through a prism for projection onto a screen.
The pixel grid in an LCD projector is relatively dense, which helps reduce the noticeable “screen-door effect” seen in older projectors. Higher-resolution models employ a technique called pixel-shifting, which doubles the number of pixels on the final image by shifting them diagonally by half a pixel once per frame. This technique eliminates the visible “staircase” effect seen in lower-resolution projectors, but may introduce noticeable artifacts in some scenes.
White light sources paired with color-splitting optics are used in most projectors today, but advanced luminaries such as lasers and Light Emitting Diodes are being employed in some products for their superior performance and energy autofocus 4k projector efficiency. These devices emit a discrete light stream for each of the red, green and blue color channels, and then combine them on a chip to create full-color images.
Imagers
The LCD (Liquid Crystal Display) technology that made its way from wristwatches and calculators to television screens and computer monitors finally found its way into projectors in the 1980s. Using a combination of LCD panels, lenses and light sources, LCD projectors offered significant improvements in image size and resolution over older projection technologies.
LCD projectors use three separate small LCD-based imagers to create the projected image, each with its own dedicated red, green and blue color channels that are combined to form a full-color video beam by dichroic mirrors and then passed through a prism. The imagers are illuminated with a metal-halide lamp that is often supplemented by a blue laser and yellow phosphor wheel in high-end models to produce brighter, more natural colors.
DLP, which uses a digital micro-mirror device instead of LCD cells, has become more popular in consumer projectors, and some manufacturers have used it to offer true UHD (3840×2160) resolution in a variety of home-theater models. DLP also offers the advantages of higher brightness for a given lamp wattage, sealed optics and a long lifespan.
LCoS (Liquid Crystal on Silicon) uses a similar process to generate the image, but the imagers are smaller and the gap between cells is filled with liquid-crystal molecules that can virtually eliminate the screen-door effect. As with LCD, some models of LCoS projectors use a technique called e-Shift that doubles the number of pixels on the screen by shifting the imagers back and forth diagonally 120 times per second.
Installation
A projector requires a powerful light source to illuminate the image on the screen. It also needs a display device to process the input signals and a system that can deliver audio. The final piece of the puzzle is software that manages these devices and other components to ensure a seamless, synchronized experience. This is called audio-visual integration, and it includes ensuring hardware compatibility and using compatible software to control the setup.
LCD projectors work a little differently than older projection technologies, which use a beam of light to pass through a frame of translucent film. They have a similar end result, however, and they’re often used in home theaters, presentations, and events. First, the lamp emits a beam of high-intensity light that passes through thousands of shifting pixels in an LCD display. It then recombines in a prism to create a crisp, colorful image that’s projected on the screen.
As you compare different projectors, pay particular attention to contrast ratio specs. While these can vary based on the manufacturer, higher numbers generally mean better performance. In addition, consider the input resolution of the source material you’ll be using most frequently. While it may seem like a good idea to purchase a model that supports the highest resolution possible, this can lead to visible pixelation and may not be a good fit for your current or future needs.