A projector is an output device that is capable of connecting to a computer, which may be an other option for a monitor or television in terms of displaying pictures to a large number of people. It takes images generated by a Blu-ray player or a computer and projects them onto a large surface like a wall or white screen. Projectors come in many shapes and sizes and are used in conditions like a classroom, home cinemas, office training or presentation sessions, etc. The projector looks like the below picture.
Commonly, projectors come a few inches tall and about a foot long and wide. They may be portable and freestanding and can be mounted on ceilings. Ceiling-mounted projectors come in a large size with a long-distance like 30 feet or more. The main applications of these kinds of projectors are places of worship, conference rooms, classrooms, and auditoriums.
On the other hand, some of the projectors have the potential to support Wi-Fi and Bluetooth conectivity, and most projectors are designed in a way that they can have different input sources, such as VGA ports for older devices and HDMI ports for newer equipment.
How a Projector Works
A projector is an optical gadget that projects a picture (or moving images) onto a surface, usually a projection screen. Most projectors create a photo through projecting a bright light via a small lens. However, some newer types of projectors can project the image directly, by using the usage of lasers.
A digital retinal display, or retinal projector, is a projector that projects a photograph at once on the retina as a substitute of using an external projection screen.
Now, Pico Projectors are also in great demand as they are very small (handheld) in size and offers high quality image.
Types of Projector
The LCD (liquid crystal display) and DLP (digital light processing) are two common types of projectors. However, CRT (cathode ray tube) projector is another type of projector, which was popular in the earlier times of projectors. In modern times, CRT projectors are no longer in use; because they provided low light output and came in a large size.
Cathode Ray Tube (CRT)
A CRT, which stands for Cathode Ray Tube projector, is a video projecting device that uses a cathode ray tube (which is small and high-brightness) as the image generating element. A Lens is kept in front of the CRT face through which the image is focused and enlarged onto a screen. In the early 1950s, color CRT projectors came on the market for the first time. Instead of a single-color CRT, most of the modern CRT projectors have colored (red, green, and blue) CRT tubes and their own lenses to generate color images and commonly come with color features. An example picture of a CRT projector is given below.
CRT projectors are not commonly in use today, as they consume high electricity and are heavy in weight, and large in size. Also, they are not portable. Although according to users, the picture quality of CRT projectors is brilliant, it may be tricky and difficult to set up a CRT projector at the initial stage. As compared to newer technologies, the projectors are capable of compatible with new improvements; hence, they are nevertheless.
Liquid Crystal Display (LCD)
An LCD projector is a type of projector based on liquid crystal displays, which is widely used in business seminars, presentations, and meetings. They utilize liquid crystal to display images, data or video, and function on transmissive technology. LCD projectors have excellent color reproduction and are cheaper to produce, which makes them more popular as compared to many alternatives. Generally, these kinds of display panels are used in many devices, such as cell phones, portable video games, Laptops, computers, and TVs. Comparing with CRT technology, the display in LCD technology is much thinner. The below picture represents how looks an LCD projector.
Digital Light Processing (DLP)
DLP projectors are utilized for front and back projection units and can be classified as one-chip or three-chip. Over 16 million colors can be produced by one-chip DLP projectors, whereas more than 35 trillion colors can be produced by three-chip models, which makes the projector capable of providing more lifelike and natural images. It is used in organizations and classrooms in terms of front projectors and also utilized for back projection in TVs. The below image is an example of a DLP projector.
What to Look for in a Projector
When picking a projector, it’s all about determining your specific goals or applications, the price you can afford, the available devices you have to accompany it like a sound system, BD player, or Wi-Fi, and so forth. Your budget is your best bet in making a shortlist of viable projectors to buy.
You can further narrow things down by your personal preferences, whether you’re willing to splurge for a specific projector-type, or if you need a low-latency projector for online first-person shooter gaming purposes. Your financial circumstances and personal tastes should serve as your guide to getting the right projector for you.
One of the most important specifications for projectors is “lumens,” which describes how much light a projector can create. This, in turn, determines how bright the image is and how big you can make it. There are a lot of problems with this spec. For one, other than the distinct “ANSI lumens” there’s no agreed-upon way to measure lumens. One company’s 3,000 might be another’s 3,500. Most manufacturers don’t specify ANSI lumens, which would be easier to compare across brands.
You can compare broad strokes however. Generally speaking a 3,000-lumen projector is probably brighter than a 2,000 model. But if you’re trying to choose between 3,000 and 3,100 lumens, good luck. Even if those numbers were accurate, that little of a difference probably won’t be visible anyway.
Laser, lamp or LED?
Projectors create light and image separately. A light source creates the light, which is then focused on an image-creating chip. Modern projectors use one of three technologies as light sources: LEDs, lasers and UHP (ultra high pressure) lamps.
UHP lamps, which are basically high-powered light bulbs, are by far the most common. These are capable of creating a lot of light and have the added bonus of being fairly inexpensive. The downside is they degrade over time. A UHP projector will never be as bright as that first time you turn it on — until you replace the lamp.
This aging is a slow process though. We’ve reviewed several that, in certain modes, have lamps that can last 15,000 hours before you need to replace them. So if you watch the projector for four hours every night, that means the lamp will last over 10 years. Prices vary, but typically a new lamp will run you $100-$300. More expensive projectors have more expensive lamps.
Light Output and Brightness
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.
Color reproduction is another important factor to consider. Check for natural flesh tones and color depth, how colors look in the brightest and darkest areas of the image, and 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.