NEC
Solutions
(America),
Inc.
Visual Systems
LT240 Installation Guide
Desktop and Ceiling Mount
v3.0
www.necvisualsystems.com
Page 3 of 7
Projection Distance and Screen Size for Desktop
The following diagram shows the relationship between projector position and the screen.
Distances are in inches. For millimeters multiply by 25.4.
Desktop Setup
C
Throw Distance
D
Screen Bottom
B
Screen Ctr
Lens Ctr
3.27"
α
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.
