... 2.low price 3.USB and RS-232 port control Digital High Pixels CCD Visualizer and visual presenter ,document camera Main ... mmmaximum 380×270 mmZoomOptical 22 times, digital 8 timesOptical 22 times, digital 8 timesOptical 22 times, digital 8 timesFocusAutomaticAutomaticAutomaticApertureAutomaticAutomaticAutomaticVideo systemCamera1 / 4 "CCD Colorful1 ...