Multilayer optical adhesives and methods of making same

An optical adhesive comprising:

• a first release film having a first release surface;
• a viscoelastic or elastomeric adhesive layer immediately adjacent the first release surface;
• a hardcoat layer immediately adjacent the viscoelastic or elastomeric adhesive layer opposite the first release film ,the hardcoat layer having a refractive index of n1, a refractive index of air being n2;
• a second release film having a second release surface, the second release surface immediately adjacent the hardcoat layer, the second release film having an unstructured surface opposite the second release surface;
• wherein a first interface between the second release film and the hardcoat layer comprises a grating having a peak to valley height h and a pitch and wherein h multiplied by |n1−n2| is in a range of about 150 nm to about 350 nm and the pitch is in a range of about 2 microns to about 50 microns, and
• wherein each of the viscoelastic or elastomeric adhesive layer and the hardcoat layer are substantially transmissive.