The image detecting module 230 can detect {HEAD ~ a first optical information} about {TAIL ~ the touch point C} and the mirror point C1 
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The image detecting module 230 can detect { HEAD ~ a first optical information } about { TAIL ~ the touch point C } and the mirror point C1
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH