Adhesive film and optical device including the same

An optical device, comprising:

• a lower device;
• an upper device;
• and
• an adhesive layer between the upper device and the lower device,
• wherein the adhesive layer includes a first adhesive layer adhered to the lower device, and a second adhesive layer on the first adhesive layer and adhered to the upper device,
• wherein the first adhesive layer includes a first acrylic resin, a first photoinitiator, and a monofunctional monomer and is without a multifunctional monomer, and the second adhesive layer includes a second acrylic resin, a second photoinitiator, and two or more multifunctional monomers, and is without the monofunctional monomer,
• wherein, by UV irradiation, the adhesive strength of the first adhesive layer is increased and the adhesive strength of the second adhesive layer is reduced,
• wherein the first acrylic resin is a copolymer of methyl methacrylate and phenyl methacrylate, and
• wherein the second acrylic resin is a copolymer of comonomers, wherein one of the comonomers is phenyl methacrylate,
• wherein the two or more multifunctional monomers include 1,3-butanediol diacrylate and glycidyl penta triacrylate, and
• wherein the monofunctional monomer in the first adhesive layer is one or more of a fluorinated monomer, MMA (methyl methacrylate), and 2HEA (2-hydroxyethylacrylate).