Projection Distance And Screen Size For Ceiling Mount; Ceiling Mount Installation; Distance Chart - NEC LT157 Installation Data

LT157/158 Installation Data
Desktop and Ceiling Mount

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

Screen Top
D
Lens Ctr
B
Screen Ctr

Distance Chart

Screen Size (4:3)
Diagonal Width(H)
inches inches
25 20
40 32
60 48
67 53.6
72 57.6
84 67.2
90 72
100 80
120 96
150 120
180 144
210 168
240 192
270 216
300 240
Note: For screen sizes not indicated on the projection tables, use the formulas on page 1.
Throw Distance
B
Height (V)
inches inches
15 6.0
24 9.5
36 14.3
40.2 16.0
43.2 17.2
50.4 20.1
54 21.5
60 23.9
72 28.6
90 35.8
108 43.0
126 50.1
144 57.3
162 64.5
180 71.6
C
C
wide - tele
inches
NA - 45.9
62.1 - 75.0
94.4 - 113.8
105.7 - 127.4
113.8 - 137.1
133.2 - 160.4
142.9 - 172.0
159.1 - 191.4
191.4 - 230.3
240.0 - 288.5
288.5 - 346.7
337.0 - 404.9
385.5 - 463.1
434.0 - NA
482.5 - NA
4.75"
5.5"
α
Lens Offset from
Mount Pipe
1.57"
α
D
wide - tele
degrees
inches
1.5 NA - 7.4
2.5 8.7 - 7.3
3.7 8.6 - 7.2
4.1 8.6 - 7.2
4.4 8.6 - 7.1
5.1 8.6 - 7.1
5.5 8.5 - 7.1
6.1 8.5 - 7.1
7.4 8.5 - 7.1
9.2 8.5 - 7.1
11.0 8.5 - 7.1
12.9 8.5 - 7.1
14.7 8.5 - 7.1
16.5 8.4 - NA
18.4 8.4 - NA
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