The mirror also independently pivots under {HEAD ~ the bias} of {TAIL ~ a spring} about the mirror pivot axis to an erected operative position wherein its upper and lower parallel edges are disposed perpendicular to the optical axis of the lens 
of
The mirror also independently pivots under { HEAD ~ the bias } of { TAIL ~ a spring } about the mirror pivot axis to an erected operative position wherein its upper and lower parallel edges are disposed perpendicular to the optical axis of the lens
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH