All fiber wavelength selective optical switch

• US 5,446,809 A
• Filed: 09/23/1994
• Issued: 08/29/1995
• Est. Priority Date: 09/23/1994
• Status: Expired due to Term

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Bailey, Timothy J., Ball, Gary A., Fritz, Daniel J.
• Primary Examiner(s): FONT, FRANK G
• Application Number:
  US08/311,644
• Time in Patent Office: 340 Days
• Field of Search: 385/16, 385/17, 385/24, 385/37
• US Class Current: 385/17
• CPC Class Codes: G02B 6/2932 comprising a directional router, e.g. directional coupler, circulator
• CPC Class Codes: G02B 6/29322 Diffractive elements of the tunable type G02B6/02195 takes precedence; optical modulation devices based on a change of the optical properties of the medium G02F1/00
• CPC Class Codes: G02B 6/351 involving stationary waveguides with moving interposed optical elements G02B6/3538 takes precedence; interposed waveguides G02B6/3502
• CPC Class Codes: G02B 6/3534 the optical element being diffractive, i.e. a grating
• CPC Class Codes: G02B 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• 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 6/3578 Piezoelectric force piezoelectric forces controlling reflecting elements in general G02B26/0858; piezo-optic devices G02F1/0131
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0009 using wavelength filters
• CPC Class Codes: H04Q 2011/0015 using splitting combining
• CPC Class Codes: H04Q 2011/0022 using fibre gratings
• CPC Class Codes: H04Q 2011/0026 using free space propagation (e.g. lenses, mirrors)
• CPC Class Codes: H04Q 2011/0039 Electrical control
• CPC Class Codes: H04Q 2011/0052 Interconnection of switches

Abstract

An all fiber wavelength selective optical switch has one or more 1×N input optical couplers 20,120, each having an input signal with a plurality of wavelengths λ₁, λ₂, λ₃. The output signals from the couplers 20,120 are connected to fibers 26,32,126,158 having Bragg gratings impressed therein, each having a central reflection wavelength, and each having a tuner attached thereto for detuning a central reflection wavelength of the gratings from a base wavelength corresponding to a wavelength of the input signal. For a given grating to pass a particular wavelength of the input signal that grating must be detuned. The fibers 26,32,126,158 are also connected to one or more N×1 couplers 66,98 to combine input signals from to different input couplers. The switch allows any combination of input wavelengths from any input signal to be selectively switched to one or more output ports.

Claims

1. A wavelength selective optical switch, comprising:

input optical coupling means, having an input port and at least one output port, for optically coupling an input signal at said input port to at least one output port, said input signal having at least one input wavelength;

an optical waveguide attached to each of said at least one output port;

at least one optical reflective element located along said optical waveguide, said reflective element reflecting a predetermined wavelength band of light centered at a predetermined central wavelength;

said central wavelength being at a base wavelength when said reflective element is not detuned, said base wavelength corresponding to a corresponding wavelength of said input signal;

tuning means, attached to said reflective element, for detuning said central wavelength away from said base wavelength so as to pass said corresponding wavelength of said input signal; and

thereby allowing any combination of the wavelengths of said input signal to be passed through all of said reflective elements along a given one of said waveguides as an optical output signal along an associated optical output waveguide.

2. The optical switch of claim 1 further comprising:

a plurality of said input optical coupling means;

at least one output coupling means, having a plurality of input combining ports each port connected to one of said output waveguides, for combining said output signals and providing a combined optical output signal indicative thereof; and

thereby allowing any combination of the wavelengths of said input signals of said plurality of said input coupling means to be part of said combined output signal at any of said output coupling means.

3. The optical switch of claim 1 wherein said reflective element is a Bragg grating.

4. The optical switch of claim 1 wherein said input coupling means comprises 1×

N optical couplers.

5. The optical switch of claim 1 wherein said output coupling means comprises N×

1 optical couplers.

6. A wavelength selective optical switch, comprising:

input optical coupling means, having an input port and at least one output port, for optically coupling an input signal at said input port to at least one output port, said input signal having at least one input wavelength;

an optical waveguide attached to each of said at least one output port;

at least one optical reflective element located along said optical waveguide, said reflective element reflecting a predetermined wavelength band of light centered at a predetermined central wavelength;

said central wavelength being at a base wavelength when said reflective element is not detuned, said base wavelength being different from a corresponding wavelength of said input signal;

tuning means, attached to said reflective element, for detuning said central wavelength away from said base wavelength so as to reflect said corresponding wavelength of said input signal; and

thereby allowing any combination of the wavelengths of said input signal to be passed through all of said reflective elements along a given one of said waveguides as an optical output signal along an associated optical output waveguide.

7. The optical switch of claim 6 further comprising:

a plurality of said input optical coupling means;

at least one output coupling means, having a plurality of input combining ports each port connected to one of said output waveguides, for combining said output signals and providing a combined optical output signal indicative thereof; and

thereby allowing any combination of the wavelengths of said input signals of said plurality of said input coupling means to be part of said combined output signal at any of said output coupling means.

8. The optical switch of claim 6 wherein said reflective element is a Bragg grating.

9. The optical switch of claim 6 wherein said input coupling means comprises 1×

N optical couplers.

10. The optical switch of claim 6 wherein said output coupling means comprises N×

1 optical couplers.