Light shield

摘要

Disclosed is a sensor shield for use in a multi-shelf merchandise display unit including a plurality of sensors mounted on a wall of the unit and opposite a source of illumination, in which each sensor corresponds to a single shelf and in which the shelves are at least semi-porous to the illumination. The shield comprises i) a plate having a length that is sufficient substantially to reduce or prevent incident illumination from the shelf above reaching the sensor; and ii) means to attach the plate to casing of or around the sensor or the wall of the unit. The plate is opaque to the illumination detected by the sensor. Also disclosed is a method to reduce the interference of light in a multi-shelf merchandise display unit from shelves above a shelf on which stock levels are being measured and a method for monitoring stock levels in a retail display cabinet by measuring light entering the retail display cabinet.

主权项

1. A sensor shield for use in a multi-shelf merchandise display unit including a plurality of sensors mounted on a wall of the unit and opposite a source of illumination, in which each sensor corresponds to a single shelf and in which the shelves are at least semi-porous to the illumination, the shield comprising:
a plate having a length or shape that is sufficient substantially to reduce or prevent incident illumination from the shelf above reaching the sensor; and means to attach the plate to casing of or around the sensor or the wall of the unit,wherein the plate is opaque to the illumination detected by the sensor.