| US 7,539,371 B2 | ||
| Optical apparatus with reduced effect of mirror edge diffraction | ||
| Massimo Martinelli, Santa Clara, Calif. (US); Long Yang, Union City, Calif. (US); Mark H. Garrett, Morgan Hill, Calif. (US); Robert Ostrom, Fremont, Calif. (US); and Joseph E. Davis, Morgan Hill, Calif. (US) | ||
| Assigned to Capella Photonics, Inc., San Jose, Calif. (US) | ||
| Filed on Apr. 21, 2008, as Appl. No. 12/107,014. | ||
| Application 12/107014 is a continuation in part of application No. 11/469394, filed on Aug. 31, 2006, granted, now 7,362,930. | ||
| Application 11/469394 is a continuation in part of application No. 11/317450, filed on Dec. 22, 2005, granted, now 7,346,234. | ||
| Application 11/317450 is a continuation in part of application No. 11/104143, filed on Apr. 11, 2005, granted, now 7,352,927. | ||
| Prior Publication US 2008/0266637 A1, Oct. 30, 2008 | ||
| Int. Cl. G02B 6/26 (2006.01) | ||
| U.S. Cl. 385—18 [385/16; 385/17; 385/19] | 50 Claims |
| 43. Optical apparatus for switching multi-channel optical signals having spectral channels of different wavelengths, comprising:
a plurality of input and output ports for optical signals having one or more of said spectral channels;
an optical beam expander and relay system adapted to receive the optical signals from one or more of the input ports, the
optical beam expander and relay system being configured to convert the optical signals to spectral beams having a predetermined
elongated beam profile;
a wavelength separator configured to spatially separate the spectral beams into constituent spectral channels; and
an array of channel micromirrors, each channel micromirror of the array being positioned to receive one of said constituent
spectral channels, the micromirrors being rotatable about a switching axis to switch said one spectral channel to a selected
output port;
wherein each channel micromirror is rotatable about an attenuation axis to vary a coupling of a corresponding spectral channel
to the selected output port to control a power level of the spectral channel output at such selected port, wherein the attenuation
axis is different from the switching axis,
wherein one or more of the channel micromirrors includes an edge that is substantially parallel to the attenuation axis,
wherein the edge includes one or more edge features that protrude above a plane of the micromirror surface and/or are submerged
below the plane of the micromirror surface, and/or have an edge shape that deviates from a straight line in a way that reduces
an increase in signal intensity of a spectral channel near side edges of a passband for a spectral channel reflected from
the micromirror relative to a central portion of the passband due to diffraction of that spectral channel from the edge when
the spectral channel is attenuated by rotating the channel micromirror about the attenuation axis.
|