Tuesday, June 16, 2009

The latest in projection screens

How often do you project visuals on a screen and the images are so pale, they can hardly be seen? Did you know that different projection screens give you different images? There is more to these devices than meets the eye.

Classroom applications
Front projection screens are the most common type of screen found in education. These screens are ideal for projecting LCD projector images. Teachers simply shine the LCD projector image onto the specialty designed screen and the image is clearly visible to large classes. Front projection screens include the following types:

  • Wall-mounted
  • Ceiling mounted
  • Recessed (hidden above the ceiling, with a slot or trap door through which the screen descends)
  • Fixed (mounted to the wall in frame)
  • Motorized or manually-operated (pull down or using a crank)

The biggest benefit of using a projection screen is size. With the proper screen and projector combination, an image can be six feet wide, eight feet wide, or more. The screens also make projected images brighter than a wall or standard pull-down materials since they have white or glass bead surfaces to better illuminate surfaces.

At the New Castle Middle School in New Castle, IN, projection screens are used in many ways. Teachers use the screens to introduce their web pages at the beginning of the school year. By pointing to various features on the projected image, students learn how to use homework helpers, get their grades or e-mail questions to the teacher.

Since individual computers may not necessarily be in use during a class period, websites can be reviewed and discussed with a whole class by projecting sites onto a screen from an LCD projector. The screens are also used for staff training and meetings.

Selecting the right screen
There are many types of screen surfaces and sizes, so choosing the right surface depends on several variables. Sizes and materials depend on room size, how much ambient light there is in the classroom, what kind of projector is being used (and if the projector is ceiling mounted or on a cart on the floor) and what kind of images are going to be projected.

In a classroom, fiberglass matt surface white wall or ceiling mounted screens are usually best. When overhead projections is being used, the glass beaded surface is not recommended. The reflective material, plus the bright white background, will cause a bright hot spot in the center of the screen. Matt white also has the major benefit of being washable.

Choose a screen that best handles your room’s needs such as size, operation (i.e. fixed frame, manual roll-up or electric roll-up) and mounting (i.e. ceiling mounted, wall mounted, or floor mounted). Determine if the seating area will require the viewers to watch the projected image from a narrow versus a wider angle of more than 30 degrees from either side of the center of the screen. A screen with a wider viewing angle – with a more uniform presentation across the screen – means more people can see clearly.

Whether you are using a state-of-the-art multimedia projector or a ten-year-old overhead projector, the right screen definitely affects any school presentation and bring it to glorious life.

Projection screen distributors

Audio Video Associates
888/435-1519 www.avaonline.com
Circle Number 320

Da-Lite Screen Co., Inc.
Circle Number 321

Draper Inc.
Circle Number 322

PolyVision Corporation
Circle number 324

Vultec Corp.
Circle number 325

By Greg Allen
Greg Allen is a social studies teacher at New Castle Middle School, New Castle District in New Castle, Inc.

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