An optical sensor having a cover layer, an emitter disposed on a first side of the cover, a detector disposed on the first side of said cover, and a plurality of stacked independent adhesive layers disposed on the same first side of the cover, wherein the top most exposed adhesive layer is attached to...http://www.google.de/patents/US20030109775?utm_source=gb-gplus-sharePatent US20030109775 - Stacked adhesive optical sensor
