Light control film for use in viewing holograms and related method

A laminated light control film assembly, comprising:

• a back film sheet having a first series of alternating opaque and transparent parallel lines extending across the surface thereof;
• a front sheet having a third series of alternating transparent and opaque lines extending across the surface thereof;
• and
• a core film sheet disposed intermediate said back film sheet and said front sheet, said core sheet having a second series of alternating opaque and transparent lines extending across the surface thereof;
• wherein said first, second, and third series of lines are arranged with respect to one another such that light traveling in a direction substantially orthogonal to the plane of the assembly is substantially impeded from passing through said assembly, and further wherein a predetermined band width of light is configured to pass through said assembly, said predetermined band width defining a predetermined angle of incidence with respect to the plane of said assembly.

A method of assembling a composite light control film laminate for use in conjunction with a light source and a diffraction grating interposed between said light source and said laminate useful in viewing holograms, comprising the steps of:

• providing a first light control film sheet comprising a first series of alternating opaque and transparent lines extending across the surface of said first sheet;
• providing a second sheet on top of said first sheet, said second sheet comprising a second series of alternating opaques and transparent lines extending across the surface of said second sheet;
• manipulating said second sheet with respect to said first sheet such that said opaque lines of said first series overlap said opaque lines of said second series by approximately fifty percent (50%);
• disposing a third sheet, having a third series of alternating opaque and transparent lines, on top of said second sheet;
• manipulating said third sheet until substantially all zero order light is blocked by the combination of said first, said second, and said third sheets;
• and
• thereafter manipulating one or both of said second and third sheets, while maintaining parallelism among said first, second, and third series of lines, to achieve predetermined wavelength selectivity of the first order light which passes through said laminate.