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6. Summary of AF circuit
winger UD
Auto focusing block is composed with three ICs 1ICs > +)
IC detects signal from IC; through ICy corresponding to conditions of subject, and calculates in-focus
direction and defocus amount simultaneous with detecting of lens-ROM-information through IC.
AF motor running direction, running amount, running speed are calculated \selected: according to lens:
ROM-information.
Running direction : determined hy in-focus direction
Running amount:
determined by pulse correspond
Running speed";
selected corresponding to defocus amount
9%: Four speeds : No regulation, High speed. Low speed. Step
ICs controls AF motor running.
through IC. monitors by encoder (photo interruptor'.
AF motor running stops after required pulse. corresponding to IC, calculation, is detected.
AF cireuit discriminates whether in-focus o not.
to defocus amount
'© Oparation with exclusive flash mounted
In case that defocus amount is not detected in low li
(flash) — Flash projects AF-assist light ~ Camera detects |
defocus amount.
jon, 1Cy outputs H signal to Fy terminal
t reflected from subject and detects