Choosing the Right Type of Projector for School, Business or Home

Choose Right Projector for your School, Business or Home

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Choose the Right Projector for your School or Business

There are several different types of projectors and it can be quite confusing when purchasing the right type of projector for your School, Business or Educational Institute. A school might require a different type of projector for a particular class or conference room or laboratory depending upon the room space, lighting and type of environment. Below are some basic classification of projectors based on the type of use rather than technical specifications. 
  1. Ultra Short Throw Projectors 
  2. Portable Projectors 
  3. Laser-LCD Projectors
  4. Entry Installation Projectors 
  5. Installation Projectors 
  6. Laser-DLP-Digital Light Processing (1 Chip or 3 Chip)
  7. LCoS - Liquid Crystal on Silicon

Ultra Short Throw Projectors

Ultra Short Throw Projectors

This type of projector has lenses that can create a much larger picture from shorter distances. Hence these projectors are a clear winner when you have a small space like a classroom or room in an apartment. However, they work perfectly fine in large areas. Unlike most projectors, which need to be about an inch away from the wall for every inch of diagonal screen size they project, Ultra Short Throw  Projector can sit up against (or within 3 to 4 inches of) the wall and still project a large image. This lets you enjoy a bigger image in a smaller space.

The ultra-short throw projectors mount only inches from the presentation (screen) wall, ideal for interactive presentations as the teacher or student can avoid being blinded by the projector light.  Very short-throw projectors tend to be significantly less, still have the advantage of mounting to the “screen” wall, rather than the ceiling (less installation cost), but aren’t as good as keeping the projection light out of the user’s eyes.

The Ultra Short Throw Projector also works well on a tabletop or shelf, so you don’t have to mount it on the ceiling to keep people from walking in between the projector and the screen. 

The ultra-short throw projector is the next major advancement in projector technology. Ultra short throw projector virtually eliminates shadows and eye glare. Ultra-short throw projection refers to a distance between 0 to 4 feet away from the projector to screen

  • Ultra Short Throw Projector can project a 100-inch image from a distance of 3 feet, better use of all available lumens.
  • It minimizes the cost as you won’t have to spend a lot of money on buying extension cables especially for HDMI which is very costly.
  • Better for a non-light controlled environment. Ambient light has less effect on the screen.
  • It can achieve a highly bright image with immense clarity from low lumens number which is not possible when using a standard projector.
  • Ultra Short Throw Projector Virtually eliminates shadows and eye glare

Portable Projectors

Maybe you’d like to project it up against the white siding of the house. Or you want to wow clients with a large presentation. Perhaps you want to view to create a movie night for your school or local church. Whatever your reasoning, you need a portable projector. Projectors have come a long way in recent years. Gone are the days where you needed to buy something as long as a log and as heavy as a car battery for decent picture quality. Now, you can pick up a light and yet highly effective portable projector for any professional or personal project you might have. Best of all, you no longer have to drop several thousand dollars for a quality picture either. But with all the different portable projectors now on the market, which one is right for you?

A portable projector can use any of the technologies but the whole idea behind a portable projector is that it should give you the flexibility to place it anywhere and use it. One of the main things a portable projector must have is a ZOOM feature. You can read more about zoom function in the section (Other things you need to know)

 

DLP Digital Light Processing Projectors


DLP projectors contain an array of microscopic mirrors that tilt either toward the light source in the projector or away from it to create a light or dark pixel on the projection screen. DLP projectors are available in single-chip and three-chip versions. Single-chip versions are cheaper than three-chip version.

Single-chip DLP offers the sharpest image you can usually find in a home projector. While all other types of projectors use three chips, also called “panels” (one for each primary colour in an image), DLP projectors use a single chip. This means there are no panel alignment problems and the image is razor-sharp. To accomplish this, a single-chip DLP projector uses a colour wheel that rotates between the three primary colours. For many people this is fine, but some users might notice a “rainbow effect.” A rainbow effect breaks up the image into separate red, green, and blue images. For example, if there is white text on the screen and you move your head, you will see the same text in red, blue, and green. Some people never see these multiple images; but others do, so be sure to watch a movie on a DLP projector before buying one.

Three-chip DLP projectors do not suffer from this rainbow effect because they use a DLP chip for each color instead of a color wheel. The drawback is that getting all three panels in perfect alignment is harder and therefore requires a more complex and expensive design. Three-chip DLP projectors are often what movie theaters use. They are capable of producing bigger, brighter images than other projector technologies. They are also available in resolutions up to 4K, and have the ability to produce more colors than other types of projectors.

DLP projectors are usually the best for watching 3D movies. Since the mirrors turn completely on or off, 3D is free of the faint double images that LCD and LCoS projectors can sometimes produce. This instant on/off ability also makes them a good choice for sports with its fast action. Video games are another good area for DLP projectors because of their fast response and lower lag times.

DLP Advantages

  • Sharpness
  • 3D
  • Fast motion
  • Brightness

DLP Disadvantages

  • Muddy rendering of black colors
  • Limited placement flexibility
  • Possible rainbow effect

LCD (Liquid Crystal Display)


LCD projectors fall right in the middle of DLP and LCoS projectors. They aren’t as bright as DLP projectors, but they are usually brighter than a LCoS projector. They don’t produce the deep blacks that LCoS projectors do, but they are better at it than DLP projectors. Motion is not as sharp and fast as what a DLP projector can produce, but motion from an LCD projector trumps that of a LCoS projector. 3D images produced by an LCD projector can be less accurate (faint double images) than 3D images produced by a DLP projector, but an LCD projector can outperform a LCoS projector due to its ability to produce bright images. LCD projectors are affordable, starting at the same price as a single-chip DLP projector. At the high-end, an LCD projectors costs just a few thousand dollars.

LCD Advantages

  • High brightness
  • Good rendering of blacks
  • Good handling of motion

LCD Disadvantages

  • Noisy dynamic iris
  • No LED or laser light engine options

Most of the above projectors, no matter which technology they employ, use high-powered light bulbs, called lamps, to produce the light that forms the images on the screen. These bulbs start at $200 and often last for 2,000 to 5,000 hours, depending on usage. If you watch a projector in the Eco mode, which usually produces more than enough light for a dedicated theater room, the bulb will last much longer. If you watch a lot of 3D movies or in a room with a lot of natural and/or ambient light, the bulb will burn out faster. Lamps also dim over time so even if the lamp life is 5,000 hours, you may find that after 2,000 to 3,000 hours of use it is dim enough to warrant buying a new bulb.

LED and Laser
If you’d rather not deal with the maintenance of replacing bulbs in your projector, consider an LED or laser video projector. The LEDs used in a projector boast much longer lifespans (20,000 hours or more) than traditional projector bulbs. There are other benefits: Red, blue, and green LEDs replace the projector’s lamp, which means no color wheel is necessary (as it is with a traditional DLP projector). Minus the color wheel, the rainbow effect is eliminated, and so is the noise generated by the movement of the wheel. LED projectors, like the Optoma HD91+, start at around $4,000 and quickly rise from there.

LED Advantages

  • 20,000+ hour lifespan
  • No color wheel
  • Fast to power up and down
  • Quiet operation
  • Energy efficient
  • Large color gamut

LED Disadvantages

  • Cannot replace the light engine if it eventually dies
  • Lower maximum brightness than bulb-based projectors
  • Expensive

Laser projectors are also relatively new. As the name implies, this type of projector uses lasers with a DLP or LCoS engine to produce their images. Just like LEDs, lasers last for 20,000 to 30,000 hours and do not dim over time. Lasers are also fast so they can turn off and on almost instantly to produce darker blacks than a traditional lamp can. Once a laser projector dies, you resurrect it by putting in a new lamp. However, with 30,000 hours of life you could use a laser projector six hours a day for 14 years before it would quit. Expect to pay at least $6,000 (the Epson LS9600e) for a laser projector.

Laser Advantages

  • 20,000+ hour lifespan
  • Infinite contrast ratio
  • Light output consistent over time
  • Quiet operation

Laser Disadvantages

  • Cannot replace the light engine if it eventually dies
  • Lower maximum brightness than bulb-based projectors
  • Expensive

LCoS (Liquid Crystal on Silicon) Projectors


Like an LCD projector, LCoS projectors shine light through a panel to create an image. Unlike LCD projectors which shine a light through a single LCD panel, the light from a LCoS projector reflects off three individual LCoS panels, which are then combined to produce the image. By reflecting the light off the panel instead of shining light through it, LCoS projectors offer the darkest black levels and contrast ratios of any technology. Better black levels make the film more immersive when viewed in a dark room. Plus, the letterbox bars on CinemaScope-format movies disappear and shadows look much better. Darker blacks also help increase the contrast ratio, which gives the image more pop. However, LCoS projectors usually cannot offer the same brightness levels of DLP and LCD projectors (which makes these two types of projectors ideal for rooms where there is a high degree of ambient light, or if you simply like to watch video with the lights on).

Because LCoS projectors usually offer lower levels of light output, they often don’t work well when paired with gigantic screens. For screens measuring less than 130 inches diagonally, they are able to produce enough light to fill the entire screen; anything larger and it’s best to use a brighter projector. They also exhibit more image blurring on fast-moving images than DLP and some LCD projectors. For film, this isn’t an issue, but it makes them problematic when watching sports and 3D content. For watching films in a dedicated room, they offer the best blacks and contrast ratios currently available. LCoS projectors start at around $2,500 and top out at $12,000 for 1080p and $25,000 for 4K.

LCoS Advantages

  • Dark blacks
  • High contrast ratio
  • Film-like images

LCoS Disadvantages

  • Low maximum brightness
  • Noisy 3D
  • Blurry fast-motion scenes
  • Expensive

Other Things you Need to Know About Projectors

Aspect Ratio

A projector's aspect ratio refers to the ratio between its width and height. For example, a 4:3 display produces an image that is more square, where a 16:9 ratio produces an image that is more rectangular in shape.

The three most common video projector aspect ratios are 4:3 (XGA & SXGA), 16:10 (WXGA & WUXGA) and 16:9 (standard HDTV, 1080p).

Aspect Ratio of Projectors

Throw Distance

Throw distance is the distance from the tip of the projector's lens to the screen.

This distance determines where the projector will sit in your classroom relative to the projection screen. For any given projector, the width of the image (W) relative to the throw distance (D) is know as the throw ratio D/W. So for example, the most common projector throw ratio is 2.0. This means that for each foot of image width, the projector needs to be 2 feet away or D/W = 2/1 = 2.0. So if I'm using a projector with a throw ratio of 2.0 and I have an image width of 5 feet, then my throw distance must be 10 feet. Conversely, if my distance from the screen is 20 feet then my image must be 10 feet wide. So the throw ratio is a simple formula that lets you easily compute throw distance or image width is given that you know one of these measurements. If the projector you choose has a different throw ratio, use this formula to compute throw distance or image width.

Zoom Function

If you've ever owned a camera or camcorder, you have no doubt had the ability to zoom in or out on the object you're trying to photograph. It essentially lets you make the object bigger or smaller without you moving. A projector zoom lens is no different. It allows you to increase or decrease the size of the projected image without moving the projector.

So why would you want to do that? There are several reasons. First, if this is a mobile projector, a zoom lens is extremely handy for setting up in rooms where you have little control over the size of the screen or where you must place the projector. Second, if you are using it in a fixed installation, a zoom lens gives you greater flexibility on where you can install the projector. And finally, if you should decide to switch to a smaller or larger screen in a fixed installation, you have a reasonable chance of making this change without having to move the projector.

Types of projector zoom lenses

Projectors usually offer two types of zoom lens, either manual zoom lenses or motorized zoom lenses. A manual zoom lens forces the user to adjust the size of the image by standing next to the projector and physically adjusting the lens by hand. Motorized or power zoom lenses allow the user to remotely press a switch, for example on a remote control, causing the projector to automatically zoom in or out and correct the size of the image.
While a motorized zoom lens makes a smooth, focused image easily attainable from anywhere in the room, manual zoom lenses have their advantage in that they allow for subtle corrections to the framing of the image. Regardless, both are preferable to projectors without a zoom lens.

Optical Zoom

Optical zoom allows the projector to enlarge the size of a projected image by extending the lens to magnify the image, without forcing the user to move the projector or to suffer a decrease in the quality of the displayed image. Projectors boasting optical zoom capabilities can often enlarge the image by twice its size without a loss in image quality.
The primary benefit of this feature is that it allows for the projector to be placed at a further distance away from the screen without reducing the quality of the image. The added benefit of the screen being further away is that cables can be shorter, meaning less cost and less signal degradation.

Digital Zoom

Digital projector zoom functions by cropping the image and then enlarging the pixels to increase the size of the projected picture. This allows for the projector to be placed further away from the screen whilst projecting a larger image. The increased throw distance provides the user with greater flexibility when positioning their projector, but the down side is that the more an image is digitally zoomed, the greater the pixilation, and the greater the reduction in quality of the image. Furthermore, it is important to note that digital zoom can only make small changes to the projector's throw ratio since factory lenses only allow for small variations in the throw distance.

When a projector's specification of 1.3 x digital zoom you may be getting a 30% larger image and with a 1.2 x optical zoom projector will give you 20% larger image.

How far do you put a projector from the screen?

A projector's distance from a screen and the size of the image it produces are proportional to each other based on the optics of the lens. As you increase the distance between the projector and a screen the image will also increase. If your projector has a zoom lens, the lens can be adjusted to change the size of the screen image without changing the distance of the projector. Since each projector lens is different, an online projection calculator tool will help you calculate the size of an image on a screen relative to how far the projector is placed from screen.