| 20100208348 | TUNABLE SPECTRAL FILTRATION DEVICE - A tunable spectral filtration device comprises at least one optical filter for intersecting a first path of converging or diverging light comprising an axis at a first angle of incidence and at least one device positioned to enable a second path of the converging or diverging light to pass through the at least one optical filter at a second angle of incidence. The optical filter comprises at least one coating and is tiltable over a plurality of angles with respect to the axis. The first angle of incidence is opposite in sign to the second angle of incidence, such that the positioning of the at least one optical filter and the at least one device substantially cancels angle-of-incidence dependent spectral broadening and/or polarization dependent spectral broadening of the converging or diverging light. | 08-19-2010 |
