Back Focus Adjustment - Ricoh Sargas-PJ1 Field Service Manual

Criteria
• Unbalance<=50cm
The focus unbalance of the projected image must be 50 cm or less. If [A] (see below) is over
50 cm, perform focus adjustment according to the following procedure:

Back focus adjustment

1. Project the full screen pattern with the lens at the maximum zoom position.
2. Measure the distance [A] between the most frontal best focus point and the most rear best
focus point along the optical axis direction.
Specifically, adjust the focus to the most frontal best focus point and shift the focus by small degrees
to the rear side to determine the most rear best focus point.
Adjustment
83