Hughes JVC 100, User Manual

Page: 22 / 128

Chapter 2—Installation
2-6
Hughes-JVC Technology Company
2.5. Lens Throw Distance and Screen Width
The distance from the closest point of the screen to the projector is known
as the throw distance.
Table 2.0-3 Lens Definitions
Phrase Definition
Throw distance Distance from the projector lens to the closest point on the screen.
Screen width Maximum width of picture that can be displayed.
To determine the throw distance from the projector to the screen, multiply the
screen width by the lens ratio.
For instance, if the projection lens being used is the 1.5:1 lens and the desired
screen width is 3.65 meters (12 feet), the distance from the closest point of the
screen to the projector lens is 5.48 meters (18 feet), as illustrated in Table 2.0-4.
Table 2.0-4 Throw Distance Calculation
Screen Width x Lens Ratio = Throw Distance
3.65 meters x 1.5 = 5.48 meters
12 feet x 1.5 = 18 feet
A pictorial illustration of throw distance and screen width is shown in Figure 2.0-7.
A graphical model is shown in Figure 2.0-8 on page 2-8. Refer to these figures for
calculating the throw distance required using the different projection lenses
available for the HJT Model 100 Projector.
WARNING!!!
Lens installation should be performed only
by factory Certified Technicians. Please contact your dealer or distributor
of the product for lens installation.
For special applications where the projector is not positioned orthogonally to the
screen, more detailed calculations are required to obtain more accurate throw
distances. Special HJT Lens Calculator software can be downloaded from HJT’s
Web page at www.hjt.com