obtaining a focus position of the object with {HEAD ~ respect} to the optical system based on {TAIL ~ the evaluation function calculation values} 
obtaining a focus position of the object with { HEAD ~ respect } to the optical system based on { TAIL ~ the evaluation function calculation values }
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL