A lighting fixture, comprising: a housing (5A, 5B); a longitudinally extending lens (20A, 20B) having a lens first latitudinal end, a lens second latitudinal end opposite said lens first latitudinal end, an interior face, and an exterior face opposite said interior face; a longitudinally extending first support structure (30B, 30A) supported by said housing (5A, 5B); said first support structure (30B, 30A) extending at least partially between said first latitudinal end and said second latitudinal end and supporting said lens (20A, 20B); said first support structure (30B, 30A) including an upper lip structure (33B, 33A) on a first side of said lens (20A, 20B) extending above a portion of said lens (20A, 20B); wherein said interior face of said lens (20A, 20B) generally faces said first side; characterized in that the lighting fixture further comprises: an optical film (40A, 40B) atop said interior face of said lens (20A, 20B), said optical film (40A, 40B) having an optical film first latitudinal end near said lens first latitudinal end and an optical film second latitudinal end near said lens second latitudinal end, said optical film (40A, 40B) extending between at least a portion of said upper lip structure (33B, 33A) and said lens (20A, 20B); and a deformable structure compressed between said upper lip structure (33B, 38B) and said optical film (40A, 40B); wherein said deformable structure exerts force on said optical film (40A, 40B), thereby compressing said optical film (40A, 40B) against said lens (20A, 20B). a housing (5A, 5B); a longitudinally extending lens (20A, 20B) having a lens first latitudinal end, a lens second latitudinal end opposite said lens first latitudinal end, an interior face, and an exterior face opposite said interior face; a longitudinally extending first support structure (30B, 30A) supported by said housing (5A, 5B); said first support structure (30B, 30A) extending at least partially between said first latitudinal end and said second latitudinal end and supporting said lens (20A, 20B); said first support structure (30B, 30A) including an upper lip structure (33B, 33A) on a first side of said lens (20A, 20B) extending above a portion of said lens (20A, 20B); wherein said interior face of said lens (20A, 20B) generally faces said first side; characterized in that the lighting fixture further comprises: an optical film (40A, 40B) atop said interior face of said lens (20A, 20B), said optical film (40A, 40B) having an optical film first latitudinal end near said lens first latitudinal end and an optical film second latitudinal end near said lens second latitudinal end, said optical film (40A, 40B) extending between at least a portion of said upper lip structure (33B, 33A) and said lens (20A, 20B); and a deformable structure compressed between said upper lip structure (33B, 38B) and said optical film (40A, 40B); wherein said deformable structure exerts force on said optical film (40A, 40B), thereby compressing said optical film (40A, 40B) against said lens (20A, 20B). an optical film (40A, 40B) atop said interior face of said lens (20A, 20B), said optical film (40A, 40B) having an optical film first latitudinal end near said lens first latitudinal end and an optical film second latitudinal end near said lens second latitudinal end, said optical film (40A, 40B) extending between at least a portion of said upper lip structure (33B, 33A) and said lens (20A, 20B); and a deformable structure compressed between said upper lip structure (33B, 38B) and said optical film (40A, 40B); wherein said deformable structure exerts force on said optical film (40A, 40B), thereby compressing said optical film (40A, 40B) against said lens (20A, 20B).