Patent ID: 8742312

Claim:
A planar detector intended for use in light curtains, comprising: a flexible layered structure that includes a multi-layer planar optical waveguide, wherein at least one layer of the planar optical waveguide has photoluminescent properties; a plurality of photoelectric sensors that form tapping points in the layered structure that are arranged at a distance from edges of the layered structure; and electrical connection lines connected to the photoelectric sensors and connected over their longitudinal course to the layered structure of the detector; wherein an external light impinging on the layered structure causes luminescence in the waveguide from an area of impingement outward toward the tapping points, wherein electrical signals are generated at the tapping points in a manner dependent on absorbed light, wherein a magnitude of the signals at the individual tapping points is dependent on their distance from the area of impingement, and wherein magnitude ratios between the signals at a plurality of the tapping points enables a calculation of distance ratios of the respective tapping points in relation to those points or areas at which light is impinging on the detector.