The No-Maintenance Projector
If you hate climbing on ladders to periodically change burned-out projector lamps and clogged air filters, Acer’s K520 is for you. Not only does the projector not have an air filter, but its innovative hybrid illumination engine has a rated lifetime of 20,000 hours of use, or about 12.5 years of harsh daily school use.
At 3.4- by 12.6- by 9.1-inches, the K520 is a mid-sized projector that stands at the border between portable and installation units; it comes with a padded case. The projector has adjustable feet front and back as well as four threaded mounting points underneath for a permanent set up. Weighing 9-pounds, the K520 can easily be handled by a single installer.
Inside the white and silver projector is a Texas Instruments Digital Light Processing (DLP) chip that projects XGA (1,024 by 768) resolution in 30-bit color. This is a step down from current WXGA projectors that put out a wide-screen 1,280 by 800 image, but more than adequate for most classroom uses. It has a 1.1X optical zoom lens and a 2X digital zoom.
Rather than a traditional high-pressure lamp and a prism that splits the light into its red, blue and green components for the DLP chip to turn into the projector’s image, the K520 uses an innovative hybrid arrangement that is a combination of LEDs and lasers. Red and blue light come from banks of LEDs, while the beam of a blue laser is bounced off of a phosphorescent disc that converts it to green light. These red, blue and green beams of light are then aimed at the DLP imaging chip and on through complicated lenses to project the image on the screen.
Not only is the solid state illumination engine in the K520 more rugged than a conventional quartz bulb, but it is rated to last 20,000 hours of use, or roughly 12.5 years of use for 8 hours every school day. Compared to the typical high-pressure lamp that lasts roughly 2,500 hours and costs $250, a school can save a lot of money over its projected life, plus have the peace of mind of knowing that you’ll never have to interrupt a lesson because of a lamp blow-out.
Because of the complex illumination technology, the K520 has a calibration routine that takes roughly 30 seconds to cycle through all the colors and make sure they’re balanced. Happily, you don’t have to perform the calibration more than once or twice a year. On the other hand, the projector lacks a test pattern that can help ease aiming and optimizing a projector.
The projector’s simple control panel is matched by its minimum of inputs, including HDMI, VGA, S- and composite-video ports, but does without either a wired LAN jack or WiFi connection. The projector also lacks a VGA-out link for streaming video from the K520 to another projector. There’s also audio-in and -out as well as an RS-232 and USB ports for monitoring and remotely controlling the projector.
In addition to turning the projector on and off, setting up the source and fine-tuning the image, the K520’s remote control can start or stop media on a notebook if the projector is connected using a USB cable; it’s not included. The remote has the creature comfort of a backlit keypad, making it particularly good for lights-off lessons, but lacks a laser pointer.
The projector starts up in 13-seconds and shuts itself down in 5-seconds, making it particularly good for stop and go lessons during the school day. On the downside, it emits an annoyingly loud beep when turning it on or off. Plus, when you start up or change the source, it takes the projector a couple of seconds to display the material.
It’s quick to warm-up and the K520 puts 2,068 lumens of light onto a screen in Bright mode. Unfortunately, the entire image takes on a greenish cast, and I prefer using the Standard or Presentation modes. There are also Video, Picture and Education modes as well as the ability to create your own custom set-up by dialing-in the brightness, contrast, gamma and other settings. Overall, the projector delivered smooth video and can project 3-D material, but you’ll have to get the special glasses.
In addition to working with a conventional white screen, the projector can be tuned to different colored backgrounds, including yellow, pink, blue and green. This makes the K520 particularly appropriate for quick set up in non-traditional teaching areas. The projector can create up to a 25-foot image, has a sharp focus and a 96-percent brightness uniformity. While its reds and blues are rich and flesh tones are realistic, the K520’s greens are a little weak. It delivered a nearly perfect bright white and showed excellent grayscale imaging. On the other hand, when using an analog source, there’s a slight rippling to the images.
While it’s on, the projector uses an economical 133 watts or about half that of comparable traditional projectors. Using the system’s Eco setting can reduce that to only 97 watts but the image starts to wash out with the lights on. The projector keeps its cool with a 98-degree Fahrenheit exhaust temperature. On the other hand, its fan runs loud at 41dBA, 3-feet from the projector’s exhaust.
The projector’s warranty might be a little troubling for an educational institution. It comes with the standard 1-year coverage for the system as well as the expected 90-day warranty on the bulb. But, the K520 doesn’t have a traditional bulb and its solid state illumination engine should outlive a lamp by years. It’s all new technology without a track record and I’d be more comfortable with projectors of this type if they included a four- or five-year warranty on the illumination engine. After all, it’s rated to last many times more than that.
Because it doesn’t ever need to have its lamp changed, the K520 is potentially the most thrifty classroom projector I’ve seen. It has estimated operating expenses of only $23 per year if it’s used for 8 hours every school day during the school year. That’s roughly one-tenth the cost of many of its competitors.
At $1,200, the K520 may cost twice as much as traditional projectors, but its ace in the hole is that it has low operating expenses and will never need to have its lamp changed. That can save seven or eight lamps over its projected lifetime, or as much as $2,000. That alone makes the K520 a bargain.
+ No lamps or filters to change
+ Backlit remote control
+ Uses half the power of conventional projector
+ Low operating expenses
+ Sharp focus
- XGA resolution