The Japanese manufacture Optex was founded in 1979 and is now becoming a world-leading company In the area of security detectors with its unique Infrared detectlon technology.(security manufacturer,security,sensor,security sensor,outdoor,indoor,outdoor sensor,indoor sensor,detector)

Visible light disturbance protection will prevent a false alarm when a 60W halogen lamp is turned on close to the detector. No false alarm is triggered even when a car flashes its headlights at the detector at a distance of 30cm (If a car passes through the detector range, of course, the exhaust heat of the car will trigger the alarm).
Also no false alarm will be triggered by sunlight up to an illumination of 100,000 lux. False alarms are most likely caused when early morning or evening sunlight pours into the room, and enters the field of view of the PIR either directly or by reflection. In such a case, however, the illumination reaches only about 50,000 lux. This prevents false alarm, due to double conductive shielding.

RFI protection has been improved to 20V/m and 30V/m or more by utilizing the double conductive shielding.
A field strength of 20V/m means that even if a 10W transmitter is placed within 1 meter of the detector and interference is produced, it will not cause false alarm. With a field strength of 30V/m, a 10W transmitter can be placed within 30-35cm of the detector and not cause a false alarm.