Optical element and display with transparent tensioned supporting films

An optical element comprising a stack of at least three juxtaposed films with at least one inner optical film and two outer transparent films exhibiting high dimensional stability, wherein a controlled tensile force is applied in at least one direction to the two outer films but not the at least one inner film, wherein the tensile force is provided from a tensioning mechanism comprising an elongated structure which protrudes through the holes or slots in the two outer transparent films and has at least one surface that is normal to the direction of the tensile force.

An optical element comprising a stack of at least three juxtaposed films with at least one inner optical film and two outer transparent films exhibiting high dimensional stability, wherein a controlled tensile force is applied in at least one direction to the two outer films but not the at least one inner film wherein the tensile force can be substantially maintained for each mechanism over the expected film dimensional change for the design temperature and humidity range of the optical element and wherein the maximum change in applied tensile force for each mechanism is less than 50% of the highest force over the expected film dimensional change for the design temperature and humidity range of the optical element.

An optical element comprising a stack of at least three juxtaposed films with at least one inner optical film and two outer transparent films exhibiting high dimensional stability, wherein a controlled tensile force is applied in at least one direction to the two outer films but not the at least one inner film wherein the tensile force can be substantially maintained for each mechanism over the expected film dimensional change for the design temperature and humidity range of the optical element and wherein the maximum change in applied tensile force is less than 25% of the highest force over the expected film dimensional change for the design temperature and humidity range of the optical element.

An optical element comprising two outer transparent films wherein at least a portion of the outer transparent films is maintained dimensionally stable by the presence of a mechanism for application of a controlled tensile force to the films wherein the maximum change in applied tensile force for each mechanism is less than 50% of the highest force over the expected film dimensional change for the design temperature and humidity range of the optical element.

An optical element comprising a stack of at least three juxtaposed films with at least one inner optical film and two outer transparent films exhibiting high dimensional stability, wherein a controlled tensile force is applied in at least one direction to the two outer films but not the at least one inner film wherein the tensile force is provided by a tensioning mechanism comprising a tensioning strap protruding through holes or slots in the outer transparent films.