BenQ HT1070 User Manual page 14

Remote control effective range
Infra-Red (IR) remote control sensor is located on the
front and the rear of the projector. The remote control
must be held at an angle within 30 degrees
perpendicular to the projector's IR remote control
sensor to function correctly. The distance between the
remote control and the sensor should not exceed 8
meters (~ 26 feet).
Make sure that there are no obstacles between the
remote control and the IR sensor on the projector that
might obstruct the infra-red beam.
14 Overview