Optical touch control device
Lens collar
Power control in projector
Position prompt device/lens regulation
http://en.wikipedia.org/wiki/Zoom_lens
Projection display system
Light source unit
Adjusting device for projector
Power supply switching device
Backlight lamp bar fixing
http://en.wikipedia.org/wiki/Backlight
Optical touch device
Light-emitting device
http://en.wikipedia.org/wiki/Projector
Optical touch-control display device
en.wikipedia.org/wiki/Power_supply
Light guide plate
