NEC
Solutions
(America),
Inc.
Visual Systems
LT240 Installation Guide
Desktop and Ceiling Mount
v3.0
www.necvisualsystems.com
Page 2 of 7
Projection Distance and Screen Size for Ceiling Mount
The following shows the proper relative position of the projector and screen. Refer to the table for installation data.
Distances are in inches. For millimeters multiply by 25.4.
Ceiling Mount Installation
Throw Distance
D
Screen Top
B
α
Screen Ctr
Lens Ctr
2.9"
Lens Offset from
Mount Center
7.6"
*7.2" pipe base
C
*5.6" flush base
*See page 6 for mount base info
Distance Chart
B
D
Diagonal
Width(H)
Height(V)
wide - tele
wide - tele
inches
inches
inches
inches
inches
30
24
18
12.6
35.7 - 43.4
3.6
19.4 - 16.2
40
32
24
16.8
48.2 - 58.4
4.8
19.2 - 16.0
60
48
36
25.2
73.2 - 88.5
7.2
19.0 - 15.9
67
53.6
40.2
28.1
81.9 - 99.0
8.0
19.0 - 15.9
72
57.6
43.2
30.2
88.1 - 106.5
8.6
18.9 - 15.8
84
67.2
50.4
35.3
103.1 - 124.6
10.1
18.9 - 15.8
90
72
54
37.8
110.6 - 133.6
10.8
18.9 - 15.8
100
80
60
42.0
123.1 - 148.6
12.0
18.8 - 15.8
120
96
72
50.4
148.1 - 178.7
14.4
18.8 - 15.8
150
120
90
63.0
185.5 - 223.8
18.0
18.8 - 15.7
180
144
108
75.6
223.0 - 268.9
21.6
18.7 - 15.7
210
168
126
88.2
260.4
314.0
25.2
18.7
15.7
240
192
144
100.8
297.9
359.1
28.8
18.7
15.7
270
216
162
113.4
335.4
404.1
32.4
18.7
15.7
300
240
180
126.1
372.8
449.2
36.1
18.7
15.7
350
280
210
147.1
435.2
524.4
42.1
18.7
15.7
400
320
240
168.1
497.7
599.6
48.1
18.7
15.7
450
360
270
189.1
560.1
674.7
54.1
18.7
15.7
500
400
300
210.1
622.5 - 749.9
60.1
18.6 - 15.7
Screen Size (4:3)
C
inches
α
degrees
Note:
For screen sizes not indicated on the projection tables, use the formulas on page 1.
