Planar lightwave wavelength blocker devices using micromachines

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).

I claim:  
     
         1 . A planar optical device for filtering a multiple wavelength optical signal comprising two or more wavelength channels, the optical device comprising: 
 an input waveguide for carrying said multiple wavelength optical signal;    an output waveguide for carrying one or more wavelength components of said multiple wavelength optical signal; and    a plurality of wavelength selective mechanical shutters for coupling said input and output waveguides, 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 block or pass 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 . (Amended) 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 two or more mechanical shutters in and out of said lightpath.  
     
     
         8 . A method for filtering a multiple wavelength optical signal in a planar optical device, said method comprising the steps of: 
 receiving one or more wavelength components of said multiple wavelength optical signal on an input waveguide;    coupling said input waveguide to an output waveguide; and    selectively blocking or passing one or more wavelength spectral portion of said multiple wavelength optical signal using a plurality of wavelength selective mechanical shutters, each of said mechanical shutters having an associated wavelength spectral portion of said multiple wavelength optical signal.    
     
     
         9 . The method according to  claim 8 , wherein said multiple wavelength optical signal is a wavelength-division multiplexed (WDM) signal comprising N wavelength channels and wherein said method further comprises the step of producing a plurality of demultiplexed output signals from said input WDM signal using a demultiplexer.  
     
     
         10 . The method according to  claim 9 , wherein a plurality of said waveguides carry each of said N wavelength channels.  
     
     
         11 . The method according to  claim 9 , 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.  
     
     
         12 . The method according to  claim 8 , wherein said plurality of mechanical shutters are opaque.  
     
     
         13 . The method according to  claim 8 , wherein said plurality of mechanical shutters are reflective surfaces.  
     
     
         14 . The method according to  claim 8 , wherein said plurality of mechanical shutters are controlled by a micromachine control element that positions said two or more mechanical shutters in and out of said lightpath.