There are two major types of video projectors available: DLP (Digital Light Processing) and LCD (Liquid Crystal Display).
1.DLP projectors employ a light source in combination with a color wheel and chip that contains microscopic tilting mirrors. The light passes through the color wheel, reflects off the mirrors, and is then projected onto a screen.
2.LCD projectors utilize a light source that passes light through 3 LCD Chips (assigned to primary colors red, green, and blue) to create and project images.
In addition to LCD and DLP technology, you should consider whether the light source used in the projector is a lamp, LED, or laser. All three options have their advantages and disadvantages:
1.Video projectors that use lamps need to be changed after about 3,000 to 4,000 hours of viewing. However, some projectors deliver upwards of 5,000 hours of viewing.
2.Video projectors that use LEDs and/or lasers as a light source have a much longer life—often as much as 20,000 hours or more.
Compare video projector light source life with an LED/LCD or OLED TV, which can last over 60,000 hours, albeit with smaller screen size.
Without sufficient light, a projector will not be able to display a bright image. If light output is too low an image will look muddy and soft, even in a dark room. The best way to determine if a projector outputs enough light to produce bright images, check the ANSI Lumens rating. This will tell you how much light that a projector can put out.
Relatively speaking, projectors with 1,000 ANSI Lumens or greater have sufficient brightness for home theater use. Room size, screen size/distance, and ambient room light connections will also affect the need for more or fewer lumens. Although video projectors’ light output capabilities have improved, they still work best in a darkened room.
Contrast ratio complements brightness. Contrast is the ratio between the black and white portions of an image. High contrast ratios deliver whiter whites and blacker blacks. A projector may have a great Lumens rating, but if the contrast ratio is low, your image will look washed out. In a darkened room, a contrast ratio of at least 1,500:1 is good, but 2,000:1 or higher is considered excellent.
Pixel Density (aka display resolution) is important. LCD and DLP projectors both have a fixed number of pixels.
1.If most of your viewing is HDTV, get as high a native pixel count as possible (preferably 1920×1080).
2.A native pixel count of 1024×768 is sufficient for DVD. However, 720p HDTV signals require a 1280×720 pixel count for native display, while a 1080i HDTV input signal needs a native pixel count of 1920×1080.
3.If you have a Blu-ray Disc player, consider a projector with 1920×1080 native pixel resolution and the ability to display the 1080p format.
If you want to jump into 4K territory, aside from the higher price tag, not all 4K projectors project true 4K resolution. It is important that you understand how 4K video projectors work and how they are labeled so that you can make the right choice for a home theater setup.
Color reproduction is another important factor to consider. Check for natural flesh tones and color depth. Check how colors look in the brightest and darkest areas of the image. Check the degree of color stability from input to input, and that you get familiar with the types of picture settings that video projectors offer. Everyone has a slight difference in color perception and what looks pleasing to them. So look carefully.
Make sure the projector has the inputs you need. All video projectors these days provide HDMI inputs, and most projectors also have VGA or DVI inputs for computers.
However, if you have older source components with composite, S-video, or component video outputs, know that many newer video projectors no longer offer these options or may offer just composite video inputs. This means that when shopping for a projector, it is definitely important to make sure that it has the connections you need.
Portability is important, not just in terms of moving or traveling with your projector, but in simplifying the installation and setup. It also makes it easier to try out different screen sizes, distances, and rooms to see which arrangement works best. If your projector is portable you can even hang a sheet on an outside wall (or garage door) in the summertime and enjoy your own drive-in movies! Watching movies outdoors using a video projector can be a great experience.