A modern video projector serves as a display medium akin to a TV monitor but instead of directly showing you the imagery, it projects it unto a blank screen, particularly when you wish to showcase a huge image or video to a larger audience or through a projection bigger than the biggest flat-screen TVs currently available.
With that said, what exactly is a projector and what should you look for in a projector?
- 1 What is a Projector?
- 2 Projector specifications explained (Projector Technology and Terminology 101)
- 2.1 Brightness
- 2.2 Contrast Ratio
- 2.3 Resolution and Native Resolution
- 2.4 Aspect Ratio
- 2.5 Throw ratio
- 2.6 Lens Zoom
- 2.7 Keystone Corrections and Lens Shift
- 2.8 Light sources
- 2.9 HDR
- 2.10 3D Technology
- 2.11 4K Projector
- 2.12 Wireless Projectors and Adapters
- 2.13 Built-In Speakers
- 2.14 MHL
- 2.15 Networking
- 3 Choosing the Right Projector
- 4 Projectors by Display Type
- 5 What Type of Projector Connectivity Do You Need?
- 6 Conclusion
What is a Projector?
A projector is an output device used to display pictures on a screen, wall, or other surfaces, typically from a computer or Blu-ray player. You could use a projector to display movies, a presentation (PowerPoint), or slide images on a large screen so that everyone in the room can see it. Today, a projector uses an HDMI cable, USB-C cable, Wifi, or VGA cable from a computer or smartphone as its input source.
It works by shining a light through a small transparent lens. However, there is a new projector technology available that allows you to project the image in a direct manner using lasers instead. This article is mostly concerned with the video projector that replaced the slideshow projector around the 1990s and 2000s.
Projector specifications explained (Projector Technology and Terminology 101)
Here are some projector terminology, technology, innovations, and specifications explained for your convenience. This should help you buy the best possible projector out there when push comes to shove.
Projector brightness or light intensity is measured by lumens. A lumen is a measure of the amount of light the lamp is capable of producing. The more lumens a lamp produces then the brighter the projector. Typically, a halide lamp produces more lumens than an LED lamp. In water terms, lumens are to light what liters per second are to water flow from the water tap.
When using a projector, optimize the room light in accordance with projector brightness. A dim projector with 1,000 to 1,200 lumens needs to dim light sources or a darkened room with all the lights out to be seen clearly. A projector with higher lumens of about 2,500 or more is also needed when you’re in brighter, larger areas where you can’t dim the lights.
Contrast is the amount of difference between the darkest and brightest areas of a picture. The better the contrast of your projector’s picture quality, the more details you get to see from the resulting image. It’s also the ratio of light reflected from an all-black image and all-white image.
Therefore, if you have a projector with a 3000:1 contrast ratio, this means the white parts are 3000 times brighter than the black image, resulting in a more detailed and less muddy or faded picture from your device. You’ll be able to better see things like motion from a video or text, graphs, pictures, and numbers from a still image.
Read more: Learn All About The Projector Contrast Ratio
Resolution and Native Resolution
Resolution is the number of horizontal pixels on a screen multiplied by the number of vertical pixels. For an HD projector, this means it must have a 1920 x 1080 resolution in order to be considered HD. Meanwhile, 4K projectors have an output of 3840 x 2160. The more pixels are available the clearer and high-fidelity the resulting digital picture will be.
In regards to native resolution, it’s the actual pixel number contained on the LCD or DLP chip of the device. Resolution refers to the resolution of the picture projected on the screen. Meanwhile, the native resolution means the real resolution of the picture element being projected by the projector.
The aspect ratio of a projector refers to the ratio between height and width. For instance, a 4:3 ratio display produces a square image usually associated with standard definition (SD) cathode-ray tube (CRT) television sets. Meanwhile, an aspect ratio of 16:9 has a rectangular screen reminiscent of movie screens in cinemas. When showing a 4:3 video on a 16:9 projector you tend to see black bars or a stretched image.
The most common aspect ratios for video projectors include 16:9 (1080p standard HDTV), 16:10 (WUXGA and WXGA), and 4:3 (SXGA and XGA). What’s the best aspect ratio projector for your needs? It depends on what’s the aspect ratio of the DVD or BD videos you watch or the presentations you present through your laptop.
The throw ratio tells you how wide the image will be when you place the projector at a certain distance from the screen. In other words, it’s the distance between the screen where the video is projected and the lens of the projector in question. For instance, a 2.4:1 throw ratio refers to a projector needing 24 feet of space to project its video on a 10-foot widescreen.
As mentioned earlier, a short-throw projector allows you to project near the screen. A traditional projector like those used in movie houses has a lengthy throw ratio that reaches the back of the audience. Throw distance and screen size matter because it tells you how far you have to place the device from a screen to get a full-sized image.
The lens zoom enables your projector to make the picture on its screen smaller or larger without moving the projector. Lens zoom is also better than digital zoom due to its high-fidelity accuracy in maintaining picture clarity and details. Although digital zooms are achievable, it typically results in pixilated results or blurring from the digital image.
It’s better to achieve an optical zoom that involves the rearrangement of lenses within the projector’s lens assembly to get a more consistently clear picture, especially when it comes to HD or 4K resolution video. The projector’s zoom feature is quite convenient in orienting your projector when you don’t have enough throw ratio space between lens and screen to work with.
When your projector isn’t in line with the center of the screen, the projection forms a “keystone” or imperfect angled rectangle shape. For example, when the projector is off the centerline horizontally, a horizontal keystone fault occurs. These keystone images or the “keystoning” effect happens because the projector image isn’t aligned at a 90° to the screen’s plane.
This is why most projectors have automatic keystone correction. This feature is available on the remote of the projector and allows the device to detect and correct the “keystoned” image automatically. This is different from the lens shift. This feature allows the lens to move itself from up and down or left to right through a dial or joystick to correct projection misalignment without moving the projector itself.
Read more: Projector Keystone Correction and Lens Shift
A projector requires a light source in order to project the image or video it has to display on a blank wall or screen. This was the case of “ancient” overhead projectors that used clear cellophane sheets and the like to project messages, letters, images, and slides on a page-sized sheet. This is also the case of the most modern projectors. In particular, all projector types use standard metal halide lamps, including the big three of LCD, DLP, and LCoS.
However, only ⅓ of the white light lumens of these lamps can be used by single-chip DLP projectors because it only has that one chip to process the three colors of the RGB spectrum as derived from the Color Wheel. Therefore, a 3,000-lumen lamp will only have a 1,000-lumen output for the RGB color lumens of a single-chip DLP projector. You need three chips to process the colors and lumens at 100%.
A standard lamp typically includes metal halide lamps such as high-intensity discharge (HID) lamps and ultra-high performance (UHD) lamps. These light sources work using a high-pressure glass bulb that contains metal halide (typically sodium iodide) and mercury vapor. These lamps are known for their efficiency, with them capable of producing 75-100 lumens of white light per watt.
3,000 hours is the average lifetime of this lamp. The lifespan of a projector lamp is rated by “half-life” or the lifetime of the lamp until its brightness is half of what it used to be. The cost for replacing a projector lamp has gone down significantly in recent times thanks to online retailers and eCommerce that sell cheap OEM or generic projector lamps as a fraction of their price.
Laser technology has also been included in projector tech due to its controlled intensity and image fidelity. Furthermore, Laser or LASER is actually an acronym for “Light Amplification by Stimulated Emission of Radiation”. It amplifies light particles in a focused beam the same way making the hole of a hose smaller makes the water pressure more powerful and concentrated.
This narrow beam of parallel light rays is useful when it comes to projectors because laser light is of the same wavelength of color and doesn’t interfere with one another. This allows the light to travel far without losing its vibrancy or strength. Projector-wise, this results in good, high-contrast picture quality with high fidelity to boot. Also, the lamp life of a projector range from 30,000 hours and above. Naturally, it’s quite expensive.
LED Projector Lamp:
LED lamps are also renowned for how long-lasting they are. They make use of the RGB or Red, Green, and Blue colors and don’t need to split weight light into individual colors in order to work. They’re like RGB displays, in a sense. As a result, the projector body is more compact with all the space saved from the simplified technology, allowing an LED projector to be smaller and lighter than standard lamp projectors.
Therefore, it’s also not unusual for a pico or pocket projector to make use of an LED lamp for the very same space-saving reasons. The half-life for an LED projector lamp is over 20,000 to 60,000 hours. Because these bulbs are solid-state devices, LED projectors are known for their sturdiness and hardiness. They can take more bumps without damage compared to standard lamp projectors.
Dual Lamp or Multi-Lamp:
A typical dual lamp projector, as its name suggests, makes use of two lamps instead of one lamp in order to make brighter, sharper, and more high-fidelity projections than their single-lamp counterparts. What’s more, if one lamp goes out, the other lamp will work harder to get the optimum brightness needed out of your device until you get a replacement lamp fitted unto it.
A dual lamp might make use of dual standard bulbs or dual LED bulbs. Some multi-lamp projectors are so advanced that they can mix and match bulb types as reserve bulbs for what’s essentially a “hybrid” projector. Speaking of which, there also exist hybrid projectors that make use of both lasers and LED technology. These projectors work by having laser-generated green that boosts LED projection brightness. They’re also not as expensive as full laser projectors.
High-dynamic-range imaging (HDR) or high-dynamic-range imaging (HDRI) is a technique used in photography and image or video displays in order to create a bigger dynamic range of luminosity than what’s possible with standard photographic or imaging techniques. Simply put, it’s another method of producing high-definition images.
In the context of projectors, duplicating HDR tech can be tricky. HDR for digital TV sets is quite different from HDR for projectors. After all, projectors are closer to movie theater displays or screens than TV screens. For instance, while the brightness for HDR is absolute brightness, projector brightness will depend on-screen material, environment, size, and distance. A calibration process is needed to achieve HDR for projectors.
3D technology in projectors is currently available in cinemas everywhere. You simply need 3D glasses in order to watch a movie that’s been given the 3D gimmick or treatment. This modern-day version of the old red-and-blue 3D movies of yesteryear works roughly the same way—to turn the picture into anaglyph images viewable by 3D glasses.
The idea here is to deliver different images to each of your eyes to give what you’re watching the illusion of having a more 3-dimensional or voluminous appearance even though it remains as flat as the screen it’s projected on otherwise. These overlapping images, to your brain, will look like what it’s looking it has depth.
4K projector technology used to be exorbitantly expensive but late 2017, it all changed. The first 4K projectors costing less than $2,000 became available in the market, some even costing as cheaply as $1,500. There’s naturally a catch to all this. The 4K of a 4K television is different for these 4K projectors.
An expensive projector with true 4K picture quality has 3840 x 2160 resolution, with each pixel serving as discrete little picture units. When you use a magnifying glass, you’ll see each pixel at the same time. These “fake” 4K projectors have lower-resolution imaging chips then offset each pixel slightly so it appears as a different pixel onscreen. The offset happens so quickly the human eye merely sees a seemingly 4K or 3840 x 2160 image from a 1920 x 1080 LCD chip!
Wireless Projectors and Adapters
There are projectors available that allow you to use them without wires or cables. They’re particularly handy as displays for networked media available through Internet streams and the like. You can even convert your existing cabled projectors and turn them into wireless projectors as well through wireless adapters.
Pocket projectors tend to be wireless as well, using the same technologies found in mobile devices in order to do away with plugs and connections. As for traditionally wired devices, they depend on an app and hardware to mirror the screen of a computer or HDTV unto the projector through a wireless signal sent by the adapter.
Some projectors double more as video or movie displays so sometimes it makes sense for the projector itself to give out sound coming from the main media player. You’ll typically see them in pico or pocket projectors so you’d have a portable video player in your hands.
Instead of having the sound come from desktop or notebook PC speaker or your home entertainment system’s stereos, you can instead use the projector speaker to play the sound. This typically necessitates the projector having a 3.5-millimeter audio jack or just a single HDMI connection since that sends both video and audio in one cable.
MHL unchains your media from your tablet or phone so that you can display photos, videos, and games on the big screen through a projector-type display. It’s a liberating type of technology involving an MHL cable that plugs into the micro-USB port of your phone or tablet. From there, the other end plugs to the HDMI port of your projector
It also works with other display media like an HDTV or computer monitor with HDMI connectivity. In other words, it’s a type of mobile to HDMI adapter that serves as an optimized connectivity solution for mobile devices to get larger displays. You also don’t need as many cables or adapters in order to make your smartphone work with your projector.
You can also deliver content to your projector through a network. This is mostly handy in business applications, such as the need to showcase real-time presentations that are updated by the second or digital signage apps. Your projector either has native networking capabilities or requires an adapter to gain such services.
For example, networking software that runs with an adapter can enable you to connect to up to 16 computers in one projector or share the same device to other presenters without changing cables since all your laptops or desktops are linked to it already. It’s also possible to share multiple different images, videos, or slides to multiple compatible projectors using one computer.
Choosing the Right Projector
There are several types of video projectors for consumers to look out for. They include the following.
Home theater projectors are video (formerly side and overhead) projectors you can use at home as an alternative to a widescreen television for your home theater needs. You can get to view movies in widescreen and full detail HD with these devices. They’re also all fully digital at this point, making them fully compatible with video players like the Blu-ray Disc or DVD player.
The advent of the video projector has made it easier to play home or commercial movies at a much larger screen than your flatscreen or even CRT TV. Old analog standard definition (SD) projectors connected to VCRs using RCA cables back in the 1990s. Nowadays, modern high definition (HD) projectors use HDMI connectors instead.
Business projectors are video projectors mostly used for video or slideshow presentations on your computer or video player. They’re also commonly seen in multimedia rooms, amphitheaters, or conferences. They’re pretty much like the home theater projector, but at times they’re capable of projecting clear pictures on much bigger screens in order to accommodate a wider audience.
Some projectors are no bigger than a home projector that you can connect to a laptop for your slideshow presentation with the help of a USB connection. Others have movie theater-quality projection abilities. There are even those that make use of laser tech to showcase high-fidelity pictures and graphics. How high-tech the business projector in question is all depends on how big the conference is.
A pico projector is a type of video projector that is designed to project content from your notebook PC, tablet, camera, or smartphone. It’s much smaller than the conference or presentation projectors from the A/V or multimedia department of your school or company. It’s supposed to be a more personalized type of projector for mainstream home use not unlike personal printers or personal computers.
It can project images on any flat surface or wall as well as a screen. These are also known as pocket/mobile/handheld projectors because of their small size. There are different types of this projector available as well, such as standalone models with HDMI and USB connectivity, USB pico projectors, embedded models included in your mobile device, and media player projectors used to play video on it via microSD cards.
A short-throw or short-throw projector is a projector capable of filling white space or a screen up close. Originally, you need a bit of distance in order to blow up an image through a projector. The farther the projector the bigger the projection that most everyone can see from afar. In contrast, a short-throw projector projects the image from nearby the screen.
It’s a new breed of projector that allows your laptop and projector—the usual combination for mobile projection or off-the-cuff presentations—to remain close to the screen in order to project the image or video rather than at the back of the audience. This also keeps audience members from accidentally casting a shadow over the projection for maximum convenience.
- Buyer’s Guide – How to Choose the Right Backyard Theater Projector
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Projectors by Display Type
Aside from projector variants sorted by size, purpose, and capabilities, there are also other projector types that are sorted out by the type of display or processing tech they use in order to work.
LCD (Liquid Crystal Display)
A Liquid Crystal Display (LCD) projector makes use of LCD technology in order to project data, images, or videos. It specifically uses transmissive technology in order to work. It’s quite a popular video projector even in the 21st Century because it’s cheaper to manufacture and its color reproduction is quite excellent. They’re common in seminars, meetings, and presentations.
A standard lamp is used as the light source for this projector type. Additionally, this device enables the light source to pass its rays through three colored LCD light panels. The panels then allow some colors to pass through them while blocking others in order to form whatever image you want to present to your audience with amazing fidelity for a device of its price range.
DLP (Digital Light Processing)
The Digital Light Processing (DLP) projector projects light beams through a color wheel, reflection mirrors, and a lens in order to work. It also uses the LCD projector’s modus operandi of allowing certain colors to pass through and blocking the rest in order to create still or moving images it then projects to the screen.
The DLP chip responsible for making the DLP projector work was originally developed by Texas Instruments. The chip is also known as the digital micro-mirror device (DMD). The DMD or DLP chip makes the DLP projector different from LCD projectors. This chip is as large as a red blood cell and is responsible for manipulating light to make images by changing mirror positions on a microscopic suspension hinge at mind-boggling speeds of 16 million cycles per second.
LCoS (Liquid Crystal on Silicon)
As for the Liquid Crystal on Silicon (LCoS) projector, it’s a device normally included in state-of-the-art commercial and home theater settings. If you’ve got a high-end video projector for the 2010s, chances are it’s an LCoS projector. They’re renowned for their ability to produce high-resolution or HD moving images unto a screen with film or digital fidelity found in movie theaters. It’s also quite pricey at $3,500 to $12,000.
The reason for its HD excellent and high price point is because it plays 4K. There are Sony 4K projectors available even back in 2013 costing about $25,000. There are also JVC LCoS projectors at the same price range. It’s known for its accurate performance, excellent black levels, least amount of pixel structure, and color vibrancy. It works by mixing LCD and DLP tech together to get the best of both worlds in microscopic suspension and liquid crystal technology.
What Type of Projector Connectivity Do You Need?
There are many types of connectors you can use in order to connect your projector to your DVD or Blu-Ray video player, laptop, smartphone, tablet, and so forth. Here are among the most common. This list even includes connections for non-HDMI legacy or vintage systems considered obsolete nowadays.
High-Definition Media Interface (HDMI) is the current audio/video interface standard for HDTVs and media players of today’s generation. It’s known for transmitting uncompressed digital video data and compressed or uncompressed digital audio data through a device that complies with the HDMI standard, such as a computer monitor, DTV, HDTV, digital audio device, and (of course) a video projector.
Many modern projectors of all types—from LCD to DLP to LCoS—make use of the HDMI format in order to produce HD 1080p to 4K resolution projections with the highest possible video fidelity that a projector can provide. Many of these projectors lack audio though, but some have speakers that take advantage of the A/V transmissions possible through an HDMI cable.
The D-sub 15 type of VGA D-plug is the most common plug used to connect to video projectors of that generation. The standard D-plug has two interlaced rows of pins spaced about a tenth of an inch, with one row missing one pin compared to the other row, thus forming a D-shaped connector.
Meanwhile, the D-sub 15 plug is notable for having a third row of pins while still maintaining the shape of the Letter D. VGA’s release allows the 15-pin plug to proliferate over the standard 9-pin monitor connector. Many video projectors required the 15-pin plug variant for maximum image fidelity.
The Digital Visual Interface (DVI) is the perfect HD connection for the projector in light of the fact that most projectors, like most computer monitors, lack a speaker. Sure, the HDMI format is more ubiquitous, but the DVI came first and it’s a more perfect fit for the silent projector. It also has analog, digital, and analog plus digital variants.
Like HDMI, it’s used to connect an uncompressed HD video source like a media player or computer to a display device like a projector. It was intended to become the digital video content standard but publishers and hardware manufacturers opted for HDMI (and, to a lesser extend, DP) due to the popularity of HDTVs and its anti-piracy safeguards that DVI lacks.
The RCA or composite video connection is the connection used for the generation of A/V where SD resolution of 480i to 576i on a single channel was the norm. You might need a projector with a composite port in order to play video from vintage VCR player, camcorder, DVD, or computer technology.
The composite video has three variants known as SECAM, PAL, and NTSC. It also has data encoded on one channel compared to the two-channel S-video and three-channel component video that are both covered below. It’s possible to play a composite video device on an HDMI projector through the use of an adapter or converter, but usually vintage devices best work with each other.
S-video is the superior standard to composite RCA that’s also known as Y/C. This projector connection format and signaling standard is used mainly to project SD video that’s 480i and 576i just like with RCA. However, it has several advantages to RCA due to its ability to separate coloring and black-and-white signals.
It produces quality SD video and images superior to composite video but not as high resolution as HDMI formats and with lower color resolution compared to component formats. SD analog TV signals travel through a number of processing steps before broadcasting, which lowers the quality of the image as info is discarded.
Component video, also known as YPbPr, is an A/V format that uses a color space—YPbPr—in order to properly render images in three channels as opposed to two with S-video and one with composite RCA video. Component video used the analog version of the YCbCr color space. YPbPr and YCbCr are numerically equal but the former is designed for analog use.
At one point, the component video was able to compete against HDMI’s 1080p with its own 1080i until the introduction of 4K HD resolutions. It also offers projector benefits like the ability to cover luminance and color information in a single cable. It also transmits a cleaner signal with more accurate color reproduction compared to S-video by separating it into different components at the source (hence the name).
A projector is also capable of connecting to a Local Area Network (LAN). As covered in the networking entry, certain projectors have connections, adaptors, or apps that allow it to network through different computers. By the way, LAN is a local network that spans a small area.
Usually, LAN connects computers within a building to either one or more projectors. This is different from a Metropolitan Area Network (MAN), which connects several building networks or LANs together to form a bigger network. Or a Wide Area Network (WAN) that isn’t geo-restricted and can connect networks within a country or state.
USB-A is the standard Universal Serial Bus (USB) port found almost in every modern computer and similar device since 1996. USB is the current industry standard for hardware connections between computers and accessories linked to it like printers, scanners, WACOM tablets, and (of course) projectors. If you want to connect your projector to a PC, it probably needs a USB port.
The USB port establishes specifications for protocols, connectors, and cables for linkages, communication, and power supply between PCs, peripherals, and so forth. USB-A is currently at version 4.0, which was recently released back in September 2019. The most ubiquitous USB-A version currently is USB-A 3.1 though.
USB Type B is less ubiquitous than the world-famous USB-A and USB-C, which covers connections for every mobile device from certain brands of smartphones to laptops. With that said, many projectors had USB-B instead of USB-C as its alternative to the standard USB-A connection port. Standard-B connectors are shaped as squares.
It’s like how B batteries are less well-known than AA and AAA batteries and are mostly used in lanterns and bicycle lamps in Europe. These connectors are characterized by its slight rounding or big square protrusion up top. They’re also colored blue instead of black to differentiate themselves further from Type A. Aside from projectors, they’re also used in floppy disk drives and hard drive enclosures.
Audio In (3.5mm)
As mentioned earlier, certain projectors had speakers in them in order to make them into a portable TV or cinema. Just find a wall or get a big enough screen and you can watch the latest movies or marathon your favorite shows with a much bigger audience than a flatscreen or a laptop could accommodate.
Additionally, aside from HDMI cables and ports that stream audio along with the video in one cable, older projectors with speakers needed a phone connector or a 3.5-millimeter audio input jack in order to play the sounds of the video along with the video itself. These ports are usually available for older legacy systems that make use of component, RCA, or S-video connections.
Although this is quite the obscure A/V connection format akin to SCART, it’s a common port found in many a vintage projector as well as radio and TV equipment. The 5BNC or 5-BNC cable is capable of sending data from one device to another by electrical signal transmission. 5BNC makes use of an insulated cable known as coaxial.
This 5BNC coaxial is composed of copper wire with tube insulation than a metal tube also made of copper. These multiple safeguards to the copper wiring is supposed to keep its signal from being disturbed by electromagnetic interference. This cable ends in 5 male BNC connectors on each side. They’re composed of a metal plug surrounding the copper wire.
Projectors have indeed come a long way since their introduction. From the camera obscura to Chinese magic mirrors, quite a lot of technological advancements all the way back to prehistoric shadow plays had to happen before a human could conceive and make use of a device to view presentations or even movies.
In summary, picking a projector depends on your specific application or goals, the available devices you’re supposed to connect to the device, and the price point you consider as perfectly affordable for your needs. Let your budget define your purchase and get the best projector your money can buy, whether it’s a DLP laser projector, a pocket LCD projector, or a hybrid using LCoS tech.