33208bae_ning_101___Desktop_Engineering__0
[1] Contact [2] Absolute [3] Center of a spherical tip mounted with light-emitting or passive targets contacts surface [4] Center of all visible light-emitting or passive targets affixed on contact probe [5] Tracks reflective or emitting targets [6] Portable; tracker is brought near the part to measure [0] 
Portable CMM: Optical Tracker
3D Scanning 101 - Desktop Engineering
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