Planar lightwave wavelength blocker devices using micromachines

• US 20050025426A1
• Filed: 08/26/2004
• Published: 02/03/2005
• Est. Priority Date: 03/15/2001
• Status: Active Grant

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Doerr, Christopher Richard
• Granted Patent: US 6,956,987 B2
• Time in Patent Office: Days
• US Class Current: 385/46
• CPC Class Codes: G02B 6/12011 characterised by the arrayed waveguides, e.g. comprising a filled groove in the array section
• CPC Class Codes: G02B 6/12014 characterised by the wavefront splitting or combining section, e.g. grooves or optical elements in a slab waveguide
• CPC Class Codes: G02B 6/12021 Comprising cascaded AWG devices; AWG multipass configuration; Plural AWG devices integrated on a single chip
• CPC Class Codes: G02B 6/3518 the reflective optical element being an intrinsic part of a MEMS device, i.e. fabricated together with the MEMS device MEMS devices in general B81B; manufacture of MEM devices in general B81C; micromechanical devices controlling the direction of light G02B26/0833
• CPC Class Codes: G02B 6/352 the reflective optical element having a shaped reflective surface, e.g. a reflective element comprising several reflective surfaces or facets that function together
• CPC Class Codes: G02B 6/353 the optical element being a shutter, baffle, beam dump or opaque element absorbers on light guide termination G02B6/243
• CPC Class Codes: G02B 6/356 in an optical cross-connect device, e.g. routing and switching aspects of interconnecting different paths propagating different wavelengths to (re)configure the various input and output links switching polarized beams G02B6/3594; power equalizers G02B6/356 and G02B6/3594; path selecting means H04Q11/0001
• CPC Class Codes: G02B 6/3596 With planar waveguide arrangement, i.e. in a substrate, regardless if actuating mechanism is outside the substrate

Abstract

A method and apparatus are disclosed for selectively passing or blocking an optical signal using an opaque or reflective shutter that is selectively positioned in or out of the light path. The disclosed wavelength blocker can be employed to filter input wavelength-division multiplexed (WDM) signal comprised of N wavelength channels, where a mechanical shutter array selectively passes each of the N wavelength channels. Each mechanical shutter may be controlled, for example, by a micromachine control element that physically lifts the shutter into or out of the lightpath. The disclosed wavelength blockers may be utilized in wavelength-selective cross connects, as well as other optical devices. In an exemplary wavelength-selective cross connect, an array of mirrors are employed in a planar waveguide having two sets of waveguide gratings intersecting at an angle. The mirrors and waveguide gratings are positioned such that if the mirror for a given channel is up (removed from the light path), then that channel passes across the device and exits the corresponding output port (bar state), otherwise the light is reflected by the mirror and exits the opposite output port (bar state).

Claims

1. A planar optical device for filtering a multiple wavelength optical signal, comprising:

a star coupler for receiving a multiple wavelength optical signal;

a plurality of waveguides coupling said star coupler to a free space region to generate a phased array of said optical signal within said free space region; and

a plurality of wavelength selective mechanical shutters positioned in said free space region at a focal plane of said phased array, each of said mechanical shutters having an associated wavelength spectral portion of said multiple wavelength optical signal and wherein said mechanical shutters are selectively positioned in or out of a light path to selectively transmit said associated wavelength spectral portion of said multiple wavelength optical signal.

2. The optical device according to claim 1, wherein said multiple wavelength optical signal is a wavelength-division multiplexed (WDM) signal comprising N wavelength channels and wherein said optical device further comprises a demultiplexer for producing a plurality of demultiplexed output signals from said input WDM signal, a multiplexer for producing an output WDM signal, and a mechanical shutter associated with each of said N wavelength channels.

3. The optical device according to claim 2, wherein a plurality of said waveguides carry each of said N wavelength channels.

4. The optical device according to claim 2, wherein said demultiplexer is embodied as a waveguide grating and wherein an aperture of said waveguide grating is substantially larger than an aperture of any one of said plurality of mechanical shutters.

5. The optical device according to claim 1, wherein said plurality of mechanical shutters are opaque.

6. The optical device according to claim 1, wherein said plurality of mechanical shutters are reflective surfaces.

7. The optical device according to claim 1, wherein said plurality of mechanical shutters are controlled by a micromachine control element that positions said plurality of mechanical shutters in and out of said lightpath.

8. A planar lightwave circuit, comprising:

a star coupler for receiving a multiple wavelength optical signal;

a plurality of waveguides coupling said star coupler to a free space region to generate a phased array of said optical signal within said free space region; and

a plurality of mechanical shutters positioned in said free space region at a focal plane of said phased array to selectively control transmission of portions of said multiple wavelength optical signal.

9. The planar lightwave circuit according to claim 8, further comprising a second planar lightwave circuit.

10. The planar lightwave circuit according to claim 8, wherein said plurality of mechanical shutters are opaque.

11. The planar lightwave circuit according to claim 8, wherein an aperture of each waveguide in said plurality of waveguides is substantially larger than an aperture of any one of said plurality of mechanical shutters.

12. The planar lightwave circuit according to claim 8, wherein said plurality of waveguides have different path lengths.

13. The planar lightwave circuit according to claim 8, wherein one or more of said plurality of shutters includes a mirror for reflecting said corresponding portion of said multiple wavelength optical signal back into said free space region.

14. A planar lightwave circuit, comprising:

an I/O waveguide for receiving a multiple wavelength optical signal;

a plurality of waveguides coupling said I/O waveguide to a free space region to generate a phased array of said optical signal within said free space region; and

a plurality of mechanical shutters positioned in said free space region at a focal plane of said phased array to selectively control reflection of portions of said multiple wavelength optical signal to a desired one of a plurality of waveguide arrays to provide switching of the multiple wavelength optical signal.

15. The planar lightwave circuit according to claim 14, further comprising at least one additional I/O waveguide, and wherein the planar lightwave circuit provides optical add/drop multiplexing of signals propagated on said I/O waveguides.

16. The planar lightwave circuit according to claim 14, wherein at least one of said plurality of waveguide arrays demultiplexes said multiple wavelength optical signal.

17. The planar lightwave circuit according to claim 14, wherein said plurality of waveguides have different path lengths.