Multilayer optical bodies

An article, comprising:

• a mirror comprising
• a plurality of first optical layers, each first optical layer being oriented and comprising a polyester having terephthalate comonomer units and ethylene glycol comonomer units, and
• a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers, each second optical layer comprising a copolymer of polymethyl methacrylate that contains comonomer units that depress a glass transition temperature of the copolymer below a glass transition temperature of the polyester of the first optical layers,
• the mirror being configured and arranged to reflect at least a portion of light over at least one wavelength region.

An article, comprising:

• a light source;
• and
• an optical body disposed to receive light from the light source, the optical body comprising
• a plurality of first optical layers, each first optical layer being oriented and comprising a polyester having terephthalate comonomer units and ethylene glycol comonomer units, and
• a plurality of second optical layers disposed in a repeating sequence with the plurality of first optical layers, each second optical layer comprising a copolymer of polymethyl methacrylate that contains comonomer units that depress a glass transition temperature of the copolymer below a glass transition temperature of the polyester of the first optical layers,
• the optical body being configured and arranged to reflect at least a portion of light over at least one wavelength region.