How to adjust the lens (continued)
How to adjust the lens mounter for addressing
unevenness of focusing
About the focus balance
zRelation between the orientation of the lens and focus surface on the screen side
If the projection lens is tilted in relation to the surface on which the images are formed, and the front (screen side) of the projection lens points downward (direction of broken arrow line) as shown in the example in the figure 1, the focus surface on the screen side is tilted so that its top is at the back of the screen and its bottom is in front of the screen.
Figure 1: Illustration of influence of lens orientation
Projection lens
Image formation surface
Focus surface on screen side
Procedure for adjusting the focus balance (adjusting the tilt with the lens mounter)
There are focus adjustment screws in three places on the lens mounter of the projector that can be used as a correction function when evenness of the whole screen cannot be obtained even after adjusting the lens focus.
zStructure of lens mounter (Figure 2, Figure 3)
Turning the focus adjustment screws in three places on the lens mounter has the effect of moving the lens slightly forward or backward. Furthermore, tightening the fixing screws in three places locks the lens bracket to stop it from moving.
Figure 2 : Front view of lens mounter (when viewed from screen side)
Lens bracket a
c
(Adjust the focus adjustment screws a, b and c after installing the lens.)
Figure 3 : Cross-section view of lens mounter part
Lens tilt direction | Screen direction |
(when adjustment screws | |
turned counterclockwise) |
|
Lens bracket Adjustment Fixing screws | Lens |
screw |
|
Hole for Allen hex socket driver Spring
