Asus S1 - Manual (Page 14)

14 LED projector E-Manual
Front view
Lens
The lens projects video or image files onscreen from your input
device.
WARNING! Do not touch the lens using your hands or any sharp
object.
Lens cover lever
Move this lever to the left to open the lens cover and to the
right to cover the lens when the LED projector is not in use.
Lens cover
The lens cover protects the lens from scratches and possible
dirt build-up.
IMPORTANT! Remove the lens cover before using your LED
projector.