Sharp VL-C780S Serviceanleitung Seite 210

VL-C780S/H/X
Vi.-C7400E
VL-CG90S/H/X
VL-CG400E
5. Focus position detection circuit
Detection of the focus position is performed using the two photo reflectors and the reflecting plate stuck
around the focus ring. The photo reflector output is inputted in comparator 1C910 pin (3) and (5). The IC910
pin (1) and (7) outputs are sent to A/F microcomputer 1C€901 (39) and (40) respectively as focus position
information.
When the pin (40) input signal is "H", the AVF microcomputer judges that the focus lens is
located at the end and reverses the rotating direction of the lens.
PHOTO
REFLECTOR
C91 R97
COMPARATOR
LENS UNIT
RELAY PWB
Figure 7-2 (h). Focus Position Detection Circuit
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