Front Screen Installations; Rear Screen Installations; Screen Size - Christie J Series User Manual

Rear Screen / Floor Mount with Mirror
ADVANTAGES
Projector is completely hidden
Usually good ambient light rejection.
Requires less space behind screen than other

rear screen installations.

2.2.3 Front Screen Installations

In front screen installations, the projector and audience are positioned in front of the screen, which can be flat
or curved.
Flat screens offer a gain of about 1.0 with a viewing angle just less than 180 degrees. This type of screen
reflects incident light equally in all directions so the audience can see the display from various angles.
Curved screens have a gain greater than 1.0 with a viewing angle much less than 180 degrees. This type of
screen does not reflect incident light equally in all directions; instead it is concentrated in a viewing cone. The
audience sitting within the viewing cone area will see a brighter image than those sitting just outside the area.
2.2.4 Rear Screen Installations
There are two basic types of rear screens:
• Diffused: A diffused screen has a surface which spreads the light that strikes it. Purely diffused screens have
a gain of less than 1.0. The advantage of the diffused screen is its wide viewing angle, similar to that of a flat
screen for front screen projection. This type of screen is suitable when a wide viewing angle is required but
there is low ambient room lightening.
• Optical: Optical screens take light from the projector and redirects it to increase the light intensity at the
front of the screen and reduce it in other areas. A viewing cone, similar to that of a curved front screen
installation is created. This type of screen is better suited for brightly lit rooms where the audience is situated
within the viewing cone.

2.2.5 Screen Size

Choose a screen size appropriate for your lens and application. If the projector will be used to display text
information, the image size must allow the audience to recognize all text clearly. The eye sees a letter clearly if
eye-to-text distance is less than 150 times the height of the letter. Small text located too far from the eye will be
illegible at a distance no matter how sharply and clearly it is displayed.
To fill a screen with an image, the aspect ratio of the screen should be equal to the aspect ratio of the image
(expressed as the ratio of its width to its height). Standard video from a VCR has a 4:3 or 1.33:1 aspect ratio.
For example, to display a VCR output with a 4:3 aspect ratio onto a 10-foot (3m) high screen, the width of the
screen must be at least 13.3 feet (4m).
J Series 2.0, 2.4 and 3.0 kW User Manual
020-100707-03 Rev. 1 (02-2014)
CONSIDERATIONS
Requires separate room or enclosure.
Installation cost is usually higher.
More involved to perform setup.
Section 2: Installation and Setup
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