Display Technology ‘Tradeoffs’

• 11/01/05

EDUCATORS SEEKING to take full advantage of the latest display technologies to enhance the learning experience are faced with a dizzying array of choices. But since display technologies are changing so rapidly, there’s often more than meets the eye, and many educators don’t understand the differences between the technologies or the benefits that each has to offer.

First, every individual school or school district will want to do its own needs assessment based on three main criteria:budget, curriculum, and room environment.

• Budget. Maximizing your budget means spending wisely— balancing both your financial constraints and your technology needs. It is important to consider the cost of ownership over the four - to six-year period before you upgrade again.
• Curriculum. The content that will be presented in a specific classroom is very important. Many times, that alone will help narrow the product category. Some materials are better delivered in a one-on-one environment on a small display placed in a cubical within a learning center, while other content can be delivered successfully on a large display with no restrictions. Content considerations also make selecting the proper resolution important. For example, it may seem strange, but a higher resolution is not always better for looking at data since today’s Web sites basically have an 800 x 600 resolution. Of course, higher resolution is better for high definition video content and for very small handheld devices like mobile phones and PDAs, which require a higher resolution to see the smaller detail. You’ve probably seen a PowerPoint presentation that was impossible to read because the fonts were too small for the projector to display properly. Imagine a projector displaying a 144- inch diagonal image, yet you cannot see it from the back of the room. The bottom line is that displays are really only as good as your source material.
• Room Environment. Check to see how many windows you have in the room. A well-lit room is perfect for learning, so reducing the amount of light merely to accommodate display technology can have a negative effect on student performance. Other considerations include student capacity, room size, and viewing angle.

Display Technology Options
Next, based on your needs assessment, consider the display technology choices currently available. These include plain old picture tubes, front projectors, LCD screens, and plasma displays—all of which make the grade, depending on your specific application.

CRT. CRT stands for “cathode ray tube,” the standard picture tube that has been used since TV was invented more than 65 years ago. Today’s CRTs provide good picture performance at a value price. Significant improvements have been made over the last three or four years in CRT TVs that display computer data for group learning. This is a cost effectiveway to incorporate computer-driven curricula and Internet browsing for group instruction. If you opt for a CRTTV, remember to select a non-scan conversion-type product,because scan-conversion technology actually converts the800 x 600 resolution down to fewer than 250 lines of resolution.Simple math will tell you that with fewer lines of resolution,the picture will be soft or fuzzy, and only large fontsor power points will look acceptable. A true SVGA monitor/TV is a good alternative to those more expensive technologiesand can operate in all lighting conditions.

LCD panel. LCD (liquid crystal display) technology passes a light source through three electronic panels—one each for red, green, and blue—combined to reproduce a great image, perfect for data. The newest LCDs also employ very fast response times to help eliminate so-called “motion artifacts,” which used to plague these flat screens when displaying fast-paced action like a sporting event or movie. For pure data, the LCD panel provides a very stable image with no image-sticking from a static image on the screen. Large LCD panels represent great display technology with rich colors and fabulous image reproduction for data display or signage content. The large 42- and 55-inch displays will see major improvements in both performance and price points over the next year. Most IT professionals are comfortable with this display technology, but it has been cost-prohibitive in the past; however, all that will change within the next year due to lower manufacturing costs and competition.

Projector. In recent years, we’ve seen drastic price reductions from various projector companies. And, as the technology has fallen below the $1,000 price point, demand has skyrocketed. However, low cost d'esn’t always mean better performance, so consider the tradeoffs. For optimum performance, select a projector that has more than 2,000 ANSI lumens. Projectors with low lumens require a more controlled environment to display a good image. Ambient or direct light will wash out your image. You may save money upfront, but the cost of ownership can be quite large due to the recurring expense of bulbs and maintenance. Without a regular“cleaning” schedule, your projector will degrade at a faster pace than one that has a regular maintenance schedule. Plus, to get the best out of your projector, you must purchase a good quality screen, because a quality projector will look even better with a proper screen.

Plasma display panel. The latest technology to enter the education field is plasma, which is almost like a new version of the old CRT technology. Just like conventional color TVs, flat panel plasma displays use phosphors illuminated by electrical charges; however, the difference is that inside a plasma screen you will find gas sandwiched between two glass plates. As for image quality, plasma ranks among the very best. It is well suited for full-motion video and data content. Best of all, it has grown much more affordable. Today’s best plasma displays offer 60,000-hour panels (now comparable to CRTs and LCDs), technologies to prevent image sticking, and advanced features that provide zoom and pan functions.

Display technology is primed for rapid growth in the 2005- 2006 school year, and you owe it to yourself and your schools to learn as much as you can before you commit. Instead of selecting one product type for all classrooms, it’s important to select the right technology for each individual classroom so teachers have the tools they need. And with various teaching styles and differing curricula for each grade, many display choices allow you to match technology to content. That equation will determine the best product for the installation, as well as enhance the learning environment.

The Dawning of Digital Television HDTV holds great promise for the classroom. Digital television is transforming the TV-set landscape, turning our living rooms into home theaters, and making its presence felt in the classroom. By 2007, the Federal Communications Commission (FCC) has mandated that new television sets must include digital tuners. Digital means images free of ghosts and interference. Digital TV’s most advanced form, high-definition television, or HDTV, delivers high-resolution, lifelike realism ina wide screen format.

All new CRT televisions, plasma displays, and LCD screens will either have a built-in digital tuner or take the form of a monitor (no tuner) that will require a set-top box to receive free over-the-air broadcasts. Those schools selecting a TV monitor that doubles as a large computer display will find a flexible, low-cost alternative for small or limited-space classrooms. Primary schools have effectively used 32-inch displays that allow students to sit in a semicircle and view the teacher’s curriculum, which keeps them focused without having to adjust the lights in the classroom. The key is to stay away from the standard old analog television, as it provides only a limited amount of usages (movies and cable channels). And in today’s complex teaching environment, you need a multimedia display in order to reduce the amount of technology outlets within a single classroom.

Todd Moffett is the education sales director for the Commercial Products Division of LG Electronics USA Inc.