Wide range tunable filter
AssigneeOptoplex Corporation
InventorsYung-Chieh Hsieh, Chiayu Ai, Chang-Tsung Lin
Life of this patent
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Abstract
A wide range tunable filter is provided. A randomly polarized incoming beam is converted into two orthogonally polarized beams. A ½ wave plate and filter block turns these two beams into four beams. Two of the four beams have a single range of wavelengths and two beams have the remaining wavelengths. Each pair of beams is orthogonally polarized. A ½ wave plate and birefringent crystal positioned after the filter block combine the two beams having the single range of wavelengths and combines the two beams having the remaining wavelengths. The invention includes a thermal compensator to correct the angle of the filter with respect to the incident light.
Claims28
A tunable filter, comprising:
- means for selecting a range of wavelengths from at least one incident beam of light comprising plurality of wavelengths to produce at least one beam comprising said range of wavelengths and at least one beam comprising the remaining wavelengths, wherein said means for selecting a range of wavelengths is operably rotatable on a pivot of rotation located at about the point where said incident beam of light is incident upon said means for selecting a range of wavelengths to minimize the location variation of said incident beam of light on said means for selecting a range of wavelengths;
- means for maintaining the propagation direction of said at least one beam comprising said range of wavelengths;
- and
- means for maintaining the propagation direction of said at least one beam comprising the remaining wavelengths, upon any range of wavelength selection.
A method, comprising:
- selecting a range of wavelengths with means for selecting a range of wavelengths, wherein said range of wavelengths are selected from at least one incident beam of light comprising a plurality of wavelengths to produce at least one beam comprising said range of wavelengths and at least one beam comprising the remaining wavelengths, wherein said means for selecting a range of wavelengths is operably rotatable on a pivot of rotation located at about the point where said incident beam of light is incident upon said means for selecting a range of wavelengths to minimize the location variation of said incident beam of light on said means for selecting a range of wavelengths;
- maintaining the propagation direction of said at least one beam comprising said range of wavelengths;
- and
- maintaining the propagation direction of said at least one beam comprising the remaining wavelengths, upon any range of wavelength selection.
Dependencies are inferred from the claim text.