User`s guide

4 13800-101-Rev. A
Installation
The AP250 should be installed according to the following
procedures:
1. If using a wall mount, it is best to locate a wall stud to
support the projectors weight.
2. The following distances are important in the set-up of a
refracting room:
REFRACTING DISTANCE (RD) The distance from the
patients eye to the screen.
PROJECTION DISTANCE (PD) The distance from the slide
to the screen.
LETTER HEIGHT (LH) The height of a 20/200 character
should be equal to the refracting distance times the
tangent of 50 minutes of arc or .014545.
LH (inches) or (mm) = RD (inches) or (mm) x .014545
For example, a refracting distance of 240 inches (20 feet)
will require a 20/200 height of 3.49 inches (240 inches x
.014545 = 3.49 inches) or for a 4000 mm (4 m) refracting
distance, you will require a letter height of 58.18 mm (4000
mm x .014545 = 58.18 mm).
3. Determine the refracting distance by measuring the
distance from the patient to the screen. Please refer to
Figures 1 and 2, below, which show combinations of
refracting and projection distances achievable with this
system.
4. Install the projector screen.
6. If attaching the AP250 to a mount, loosen the mounting
screw (see "Instrument Components," p. 3, #8) and insert
the projector mount onto the ball. Tighten screw, allowing
for some movement of the projector for final positioning.
Fully tighten the screw after final adjustment and alignment
of the system.
NOTE: There should be a distance > 5 ft. (1.5 m) between
remote control and the projector. Make sure no objects
that could interrupt remote control signals are located
between remote control and projector.
7. Make sure that voltage indicator number corresponds with
the available local mains.
8. Plug power cord into AC inlet and into a wall power outlet.
Set the power switch to the ON position.
PROJECTION RANGE LIST
Projection Minimum Maximum
Distance Refracting Refracting
Distance Distance
FT M FT M FT M
10 3.0 7.4 2.3 11.6 3.5
11 3.3 8.2 2.5 12.7 3.9
12 3.6 8.9 2.7 13.0 4.2
13 3.9 9.6 2.9 15.0 4.6
14 4.2 10.4 3.2 16.2 4.9
15 4.5 11.1 3.4 17.3 5.3
16 4.8 11.8 3.6 18.5 5.6
17 5.1 12.6 3.8 19.6 6.0
18 5.4 13.3 4.1 20.8 6.3
19 5.7 14.0 4.3 21.9 6.7
20 6.0 14.8 4.5 23.1 7.0
21 6.4 15.5 4.7 24.3 7.4
22 6.7 16.2 4.9 25.4 7.7
23 7.0 17.0 5.2 26.6 8.1
24 7.3 17.7 5.4 27.7 8.4
25 7.6 18.4 5.6 28.9 8.8
26 7.9 19.2 5.8 30.0 9.2
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
REFRACTING DISTANCE (FT.)
5
10
20
15
25
30
PROJECTION DISTANCE (FT.)
PROJECTION RANGE GRAPH
Maximum
Minimum
Figure 1 - Projection Range List in meters and feet. Figure 2 - Projection Range Graph in feet.