Optical routing mechanism with integral fiber input/output arrangement on MEMS die

1. A wavelength router for receiving, from an input fiber, light having a plurality of spectral bands and directing subsets of the spectral bands to respective ones of a plurality of output fibers, the wavelength router comprising:

a free-space optical train disposed to provide optical paths for routing the spectral bands between the input fiber and the output fibers; and

an optical routing mechanism integrally mated by a common surface with end portions of the input and output fibers, the optical routing mechanism having a plurality of dynamically configurable routing elements, each such routing element being configured to direct a given spectral band to different output fibers depending on a state of such routing element.

2. The wavelength router recited in claim 1 further comprising a plurality of fiber folding elements disposed over the common surface, each such fiber folding element oriented to direct light between a respective one of the fibers and a path parallel to an optical axis of the free-space optical train.

3. The wavelength router recited in claim 2 wherein:

the dynamically configurable routing elements comprise tiltable micromirrors formed over the common surface; and

the optical routing mechanism further has a plurality of fixed mirrors, each such fixed mirror disposed to encounter the given spectral band depending on the state of such routing element.

4. The wavelength router recited in claim 1 wherein ends of the input and output fibers are disposed in a common plane orthogonal to an optical axis of the free-space optical train.

5. The wavelength router recited in claim 4 further comprising a common fiber folding element disposed over the common surface and oriented to direct light between each of the fibers and paths parallel to an optical axis of the free-space optical train.

6. The wavelength router recited in claim 5 wherein:

the dynamically configurable routing elements comprise tillable micromirrors formed over the common surface; and

the optical routing mechanism further has a first fixed mirror disposed to encounter each spectral band and a plurality of second fixed mirrors, each such second fixed mirror disposed to encounter the given spectral band depending on the state of such routing element.

7. The wavelength router recited in claim 6 wherein the first fixed mirror and the plurality of second fixed mirrors are disposed to encounter the given spectral band at points substantially lying along a conic-surface envelope.

8. The wavelength router recited in claim 7 wherein the conic-surface envelope comprises a parabolic-surface envelope.

9. The wavelength router recited in claim 7 wherein the conic-surface envelope comprises an elliptical-surface envelope.

10. The wavelength router recited in claim 4 wherein ends of the fibers are disposed substantially according to the relationship x 1 ≃x 2 +½x 3 , where each x i measures a distance along an axis parallel to the common plane and orthogonal to a symmetry axis along which the dynamically configurable routing elements are disposed, x 1 representing a distance between the symmetry axis and the input fiber, x 2 representing a distance between the symmetry axis and a nearest of the output fibers to the symmetry axis, and X 3 representing a distance between the nearest output fiber and a farthest of the output fibers from the symmetry axis.

11. The wavelength router recited in claim 5 further comprising a window disposed substantially orthogonally to the optical axis and adapted for hermetically sealing the optical routing mechanism.

12. The wavelength router recited in claim 4 wherein the common plane is substantially parallel to the common surface.