Holographic sensor
AssigneeDublin Institute of Technology
InventorsIzabela Naydenova, Hosam Sherif, Suzanne Martin, Raghavendra Jallapuram, Vincent Toal
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Abstract
A sensor device comprising a holographic element comprises a grating or hologram recorded in a holographic recording medium wherein at least one physical and/or chemical and/or optical characteristic of the holographic element or the image produced by it varies as a result of variation in relative humidity or moisture content in the air surrounding the element. Also provided is an acrylamide-based photopolymer and an acrylamide-based reflection hologram.
Claims38
A reflection hologram recorded in a dry, acrylamide based photopolymer material, the hologram having a diffraction efficiency between about 25% and about 30% at spatial frequencies greater than 4500 lines mm−1, the photopolymer material comprising polyvinyl alcohol as a polymeric binder, the polyvinyl alcohol having a percentage hydrolysis of less than 85%.
A reflection hologram recorded in a dry, acrylamide based photopolymer material, the hologram having a diffraction efficiency between about 25% and about 30% at spatial frequencies greater than 4500 lines mm−1, the photopolymer material comprising polyvinyl alcohol as a polymeric binder, the polyvinyl alcohol having a percentage hydrolysis of about 80%.
Dependencies are inferred from the claim text.