www.necvisualsystems.com
LT245
Page 1 of 7
NEC
Solutions
(America),
Inc.
Visual Systems
LT245 Installation Guide
Used
with
4:3
and
16:9
screens
v1.1
Contents
Product Description, Lens Specs,
Screen/Aspect Ratio, Notes and Formulas
Pg. 1
Diagrams and Distance Charts, 4:3 Screens
Pg. 2
16:9 Screens
Pg. 3
Cabinet
Dimensions,
Top,
Front
and
Right
Pg. 4
Bottom,
Back
and
Left Pg. 5
Ceiling
Mount
Dimensions Pg. 6
Input
Panel
and
Control
Codes
Pg. 7
Product Description
Type:
1chip
DMD
TM
projector,
Color
Wheel:
4
segment
Resolution: 1024
x
768
(4:3)
Dimensions:
10.24”(W)
x
4.84”(H)
x
12.40”(D)
1024
x
576
(16:9)
Weight: 7.1
lbs
Brightness:
2200 ANSI lumens
Lens Specifications
Throw Ratio: 1.5 - 1.9:1(for 100” diagonal)
Focal
Length:
22.1mm
–
26.5mm
Offset Angle: 15.7
°
-18.7
°
(for
100”
diagonal)
F/#: 2.2
–
2.5
Screen
Sizes:
30”-500”
diagonal
(4:3)
Manual
Zoom
/
Focus
Screen/Aspect Ratio
Both 4:3 and 16:9 screens are fully supported
with proper aspect ratio control for both type sources using NEC developed
scaling technology. By selecting the screen type in the menus, Aspect Ratio control is reconfigured for that screen type.
•
For a 4:3 screen; select “4:3” in the “Screen” menu for proper aspect ratio control of 4:3 and 16:9 sources.
•
For a 16:9 screen; select “16:9” in the “Screen” menu for proper aspect ratio control of 4:3 and 16:9 sources.
*Factory default “Screen” setting is “4:3”.
Notes
For screen sizes not indicated on the projection charts, use the formulas below.
The ceiling must be strong enough to support the projector and the installation must be in accordance with any local
building codes.
Distances are in inches, for millimeters multiply by 25.4.
Distances may vary
±
5%.
Formulas
The Projection Formulas use the image width for calculation. Image width is the same for all aspect ratios, only vertical image size
varies. For proper projector placement, determine the image width for a desired screen size. Use the Screen Formulas below to
calculate all screen dimensions. Plug in the image width for “W” in the Projection Formulas.
Refer to the diagrams and charts for popular screen sizes on page 2 and 3.
Definitions:
4:3 Screen Formulas:
W
=
Image
Width
W
= H x 4/3
H
=
Image
Height
(Size)
H
= W x 3/4
B
= Vertical distance between lens center and screen center
Screen Diagonal
= W x 5/4
C
= Throw distance
D
= Vertical distance between lens center and screen top
16:9 Screen Formulas:
(screen bottom for desktop application).
W
= H x 16/9
α
= Projection angle
H
= W x 9/16
Screen Diagonal
= W x 18.35756/16
Projection Formulas:
B
= 0.5248W - 0.053
Vertical Position for a 16:9 screen: The Vertical Position adjustment moves the 16:9
C
(wide) = 1.5692W – 1.978
image up and down in the unused portion of the 4:3 panel. This adjustment is only
C
(tele) = 1.8836W – 1.9
available when the projector is set for ‘16:9’ in the
‘
Screen’ menu. The range of Vertical
D(4:3)
= 0.1498W - 0.053
Position is dependent on aspect ratio and 3D Reform used. If 3D Reform is not used,
D(16:9)
= 0.24355W - 0.053
the approximate range of Vertical
P
osition is +/-0.167H (H=Screen Height) when using
α
(wide) = tan
-1
(B/C(wide))
a 16:9 screen.
α
(tele) = tan
-1
(B/C(tele))
