NOVELTY - The optical assembly comprises an optical device having an optical surface, and a pre-formed encapsulant film that entirely covers the optical surface, where the encapsulant comprises a first layer (106) and a second layer (108) each including first and second silicone-containing hot melt composition, a first major surface (110) and a second major surface (112). The first major surface of the second layer is in contact with the first major surface of the first layer. The first and the second silicone-containing composition is a reactive silicone-containing hot melt composition.    USE - The optical assembly is useful in e.g. photovoltaic panel, an optocoupler, a household appliance, a toys/games instrumentation, a security equipment, switches, an architectural lighting, emergency lighting, monochrome message boards, mobile phones, personal digital assistants, digital cameras, bar code readers, and optical switches.    ADVANTAGE - The optical assembly exhibits thermal stability and/or long term durability.    DETAILED DESCRIPTION - The optical assembly comprises an optical device having an optical surface, and a pre-formed encapsulant film that entirely covers the optical surface, where the encapsulant comprises a first layer (106) and a second layer (108) each including first and second silicone-containing hot melt composition, a first major surface (110) and a second major surface (112). The first major surface of the second layer is in contact with the first major surface of the first layer. The first and the second silicone-containing composition is a reactive or non-reactive silicone-containing hot melt composition. One of the first layer and the second layer has a shore A hardness gradient from the first major surface to the second major surface of the first layer or from the first major surface to the second major surface of the second layer. A thickness of the encapsulant is 0.5-5000 mu m. One of the layers is cured. The assembly further comprises a tie layer made of resin. An INDEPENDENT CLAIM is included for a method for manufacturing an optical assembly.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic side view of a layered polymeric structure utilized as an encapsulant in an optical assembly.    Release liner (104)    First layer (106)    Second layer (108)    First major surface (110)    Second major surface. (112)