Movement or presence signaling device, has oblong detecting area limiting device with inner hollow space and opened at two sides lying opposite to each other for limiting detecting area of lens for arrangement of lens

摘要

The movement or presence signaling device (1) has a lens (30) to bundle incident ray beams, particularly infrared rays on a detector. An oblong detecting area limiting device (10,11) with an inner hollow space and opened at two sides lying opposite to each other is provided for limiting the detecting area of the lens for arrangement of the lens. The detecting area limiting device is tubular shaped. Independent claims are also included for the following: (1) a detecting area limiting device for the movement or presence signaling (2) a set of movement or presence signaling device and a set of detecting area limiting device (3) a method for determining the length of the detecting area limiting device. device.