85'' Optical whiteboards 32768x32768 resolution Dual touch Finger,stylus input optical imaging technology High quality 85'' Optical whiteboards Features: 1. Positioning sensor technology:Optical Imaging Technology 2 Dual touch and dual user writing supported, 3.Fit for roduct size:78'',84'' and 88'' 4.Resolution: ≥32768×32728 5.Very easy to maintain and repair (just have 2 CCD cameras to replace ...