The GUARDIAN 1 is an overhead sensor for pedestriansliding doors. The sensorhas combined motion andpresence (safe) detectionzones. The sensor is basedon CMOS camera technology and detection on imageprocessing. The motion zonereacts only on movementwhereas the presence zonereacts on both movementand presence. The motionzone can be blanked in 3directions (front, left andright) in order to avoid detection of unwanted objects.The presence zone is taughtinto the sensor by recognition of some standard testtargets in the setup phase.The presence zone alsoadapts to the surroundingsto work in different weatherconditions. The sensor hasseparate outputs for themotion and presence zonesas well as a test input to testthe sensor function for eachdoor cycle.