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17

Note

• 

The projector lens should be centred in the middle of the screen. If the horizontal line
passing through the lens centre is not perpendicular to the screen, the image will be
distorted, making viewing difficult.

• 

For optimal image, position the screen so that it is not in direct sunlight or room light.
Light falling directly on the screen washes out the colours, making viewing difficult. Close
the curtains and dim the lights when setting up the screen in a sunny or bright room.

• 

A polarising screen cannot be used with this projector.

• 

The graph below is for 100 inches (254 cm) screen with 4:3 normal mode.

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19

• 

Place a translucent screen between the projector and the audience.

• 

Reverse the image by setting “Rear” in “PRJ Mode”.

• 

Place a mirror (normal flat type) in front of the lens.

When using a mirror, be sure to carefully position both the projector and the mirror so the light does not
shine into the eyes of the audience.

• 

It is recommended that you use the optional Sharp ceiling-mount bracket for this
installation. Before mounting the projector, contact your nearest Sharp Authorised
Projector Dealer or Service Centre to obtain the recommended ceiling-mount bracket
(sold separately.) (AN-NV6T ceiling mount bracket, its AN-TK201 and AN-TK202
extension tubes)

• 

Ensure you adjust the position of the projector to match the distance (H) from the lens
centre position to the lower edge of the image, when mounting the projector on the
ceiling.

• 

Invert the image by setting “Ceiling + Front” in “PRJ Mode”. 

20

Positioning a projector is not just a simple case of installing the correct bracket to the ceiling
and hoping for the best. The type of lens that the projector has will affect how big the image
can be. The two most important considerations, in selecting the type of lens your projector
should have, are the desired image size and desired or available throw distance. These two
measurements can be used to calculate the lens ‘Throw Ratio’ that is needed. This is the
throw distance to screen width ratio.

All three measurements are directly related so knowing the throw ratio and desired screen
size, it is easy to determine the throw distance.

The simple calculation triangle below can be used:

So 

D=W x R

W=D ÷ R

R=D ÷ W

Example  A projector has a lens whose throw ratio is 0.9:1, the required screen width is
2m what is the throw distance?

D=W x R 

D = 2 x 0.9 = 1.8m

In order to give more flexibility, most projectors have a zoom control. This allows the image to
be adjusted for size without moving the projector. The figures given here indicate that by
using the zoom control, throw ratios of 1.5:1 through to 1.9:1 can be achieved. 
The amount of zoom available is specified as a multiplier.
A quoted zoom value of 1-1.3x means that the image can be enlarged by up to 30% with the
zoom control.

D

Screen sizes are usually measured diagonally. As the throw ratio is determined from the
throw distance and screen width, the diagonal measurement should not be used in the
calculation.