US4720160A — Optical resonant cavity filters

Claim 1

Independent Claim 57 words

A filter system for coupling an input optical waveguide to an output optical waveguide, said system comprising a resonant waveguide cavity formed with a dispersive couple providing a wavelength dependent filter whereby the effective length of said cavity determines a plurality of resonant wavelengths and said dispersive couple is more selective of one of said resonant wavelengths.

Claim 2

Dependent Claim 57 words

A filter system for coupling an input optical waveguide to an output optical waveguide, said system comprising a resonant waveguide cavity formed with a dispersive couple providing a wavelength dependent filter whereby the effective length of said cavity determines a plurality of resonant wavelengths and said dispersive couple is more selective of one of said resonant wavelengths.

Claim 3

Dependent Claim 23 words

The filter system of claim 1 wherein said cavity comprises first and second optical waveguide segments with at least one dispersive coupling therebetween.

Claim 4

Dependent Claim 32 words

The filter system of claim 2 wherein said input waveguide is laterally coupled to said first optical waveguide and wherein said output optical waveguide is lateraly coupled to said second optical waveguide.

Claim 5

Dependent Claim 25 words

The filter system of claim 2 wherein said first and second optical segments are linear segments disposed generally parallel to and coupled to each other.

Claim 6

Dependent Claim 66 words

The filter system of claim 4 wherein said first optical segment includes a reflective arrangement at one end and said second optical segment includes a reflective arrangement at an end opposite from said one end of said first segement to provide a resonant cavity whose length is twice the distance from said one end of said first segment to said opposite end of said second segment.

Claim 7

Dependent Claim 38 words

The filter system of claim 3 wherein said first and second optical segments together define a closed-loop cavity formed by opposite ends of one of said segments being coupled to opposite ends of the other of said segments.

Claim 8

Dependent Claim 46 words

The filter system of claim 6 wherein the effective lengths of said first and second segments are such that essentially all energy for a select wavelength is transferred between said segments at each of said couplings to provide a continuous closedloop path for said select wavelength.

Claim 9

Dependent Claim 105 words

An optical filter system for transferring light energy from an input optical waveguide to an output optical waveguide, said system comprising a block of optical waveguide material drawn with a plurality of optical fibers embedded therein extending along a given axis thereof, at least a given portion of said block having a pair of generally parallel end faces extending normal to said axis and in intercepting relation to one or more of said embedded optical fibers, and reflective means located at each end of said given portion of said block to form a linear optical resonator cavity comprising at least one of said embedded fibers.

Claim 10

Dependent Claim 105 words

An optical filter system for transferring light energy from an input optical waveguide to an output optical waveguide, said system comprising a block of optical waveguide material drawn with a plurality of optical fibers embedded therein extending along a given axis thereof, at least a given portion of said block having a pair of generally parallel end faces extending normal to said axis and in intercepting relation to one or more of said embedded optical fibers, and reflective means located at each end of said given portion of said block to form a linear optical resonator cavity comprising at least one of said embedded fibers.

Claim 11

Dependent Claim 30 words

The invention of claim 8 including coupling means formed in said block for facilitating the lateral coupling of said input and output waveguides to select ones of said embedded fibers.

Claim 12

Dependent Claim 48 words

The invention of claim 9 wherein said input and output waveguides are fibers and said coupling means includes at least one indentation formed in said block in close proximity to at least one of said embedded fibers for receiving at least one of said input and output waveguides.

Claim 13

Dependent Claim 113 words

An optical filter system for transferring at least one select wavelength of optical energy from an input optical waveguide supporting a broad range of wavelengths within a given wavelength band to an output optical waveguide, said system comprising an optical waveguide filter coupled to said waveguides, said filter having an optical waveguide resonator arrangement for resonating a plurality of wavelengths within said given band including said select wavelength and said resonator arrangement including wavelength dependent means for discriminating against unwanted wavelengths and for preferentially resonating said select wavelength for transfer to said output waveguide whereby energy of said select wavelength is transferred thereto and other wavelengths within said input waveguide are relatively uneffected.

Claim 14

Dependent Claim 113 words

An optical filter system for transferring at least one select wavelength of optical energy from an input optical waveguide supporting a broad range of wavelengths within a given wavelength band to an output optical waveguide, said system comprising an optical waveguide filter coupled to said waveguides, said filter having an optical waveguide resonator arrangement for resonating a plurality of wavelengths within said given band including said select wavelength and said resonator arrangement including wavelength dependent means for discriminating against unwanted wavelengths and for preferentially resonating said select wavelength for transfer to said output waveguide whereby energy of said select wavelength is transferred thereto and other wavelengths within said input waveguide are relatively uneffected.

Claim 15

Dependent Claim 19 words

The system of claim 11 wherein said wavelengths dependent means comprises a dispersive couple providing a wavelengths dependent filter.

Claim 16

Dependent Claim 18 words

The system of claim 12 wherein said resonator arrangement includes a waveguide loop closed by said dispersive couple.

Claim 17

Dependent Claim 45 words

The system of claim 11 wherein said resonator arrangement includes at least one resonator cavity coupled to said output waveguide near a proximate end thereof, and said output waveguide includes reflective means located at said proximate end for reflecting energy directed toward said proximate end.

Claim 18

Dependent Claim 56 words

The system of claim 11 wherein said resonator arrangement includes a pair of waveguide resonators intercoupled to each other, and said wavelength dependent means being defined by each of said resonators having a different effective length to resonate at different groups of wavelengths but with said one select wavelengths being generally coresonant in both said resonators.

Claim 19

Dependent Claim 25 words

The filter system of claim 15 wherein said resonators are integrally formed with one of said resonator including portions of the other of said resonators.

Claim 20

Dependent Claim 16 words

The filter system of claim 16 wherein said one resonator is coupled to said input waveguide.

Claim 21

Dependent Claim 16 words

The filter system of claim 17 including means for providing amplification in one of said resonators.

Claim 22

Dependent Claim 62 words

The filter system of claim 16 wherein said other resonator is a first waveguide segment formed as a first closed loop and said one resonator is a second waveguide segment coupled to said first closed loop at two spaced apart points with the waveguide portion between said spaced points and portions of said first closed loop form a second closed loop resonator.

Claim 23

Dependent Claim 20 words

The filter system of claim 19 wherein said waveguide portion between said spaced points is coupled to said input waveguide.

Claim 24

Dependent Claim 21 words

The filter system of claim 19 wherein said second waveguide segment is coupled to both said input and said output waveguide.

Claim 25

Dependent Claim 52 words

The filter system of claim 19 wherein said waveguide portion between said spaced points is coupled to both said input and output waveguides with said output waveguide spaced downstream of said input guide as viewed in the direction of travel of the wave input to said second loop by said input waveguide.

Claim 26

Dependent Claim 16 words

The filter system of claim 22 including amplifying means for providing gain in said second loop.

Claim 27

Dependent Claim 27 words

The filter system of claim 23 wherein said amplifying means includes means for injecting light energy in one end of said second segment forming said second loop.

Claim 28

Dependent Claim 33 words

The filter of claim 15 wherein said resonators are formed as at least two fiber cores spaced apart within a single cladding arrangment to form multiple resonators within an integral multiresonant cavity waveguide.

Claim 29

Dependent Claim 31 words

The filter of claim 25 wherein said resonators are formed as preform cores spaced apart within a single cladding arrangment and drawn down to form said multiple resonators in one waveguide.

Claim 30

Dependent Claim 15 words

The system of claim 11 including means for providing amplification in one of said resonators.

Claim 31

Dependent Claim 28 words

The system of claim 11 wherein said resonators are waveguide loops formed of optical fibers, and the diameter of said loops is from about 0.5 to 5.0 cm.

Claim 32

Dependent Claim 18 words

The system of claim 11 wherein said resonators are intercoupled to each other through an intermediate waveguide section.

Claim 33

Dependent Claim 72 words

An optical waveguide fiber cavity comprising an optical fibers segment of fixed length having substantially parallel end faces and a longitudinally extending optical fiber core surrounded by cladding material, said segment having opposed, longitudinally extending flats to provide reduced cladding thickness between the core and the surface of the flats for enhanching lateral coupling there at, and reflective means located at each of said end faces to effect an optical resonant cavity.

Claim 34

Dependent Claim 72 words

An optical waveguide fiber cavity comprising an optical fibers segment of fixed length having substantially parallel end faces and a longitudinally extending optical fiber core surrounded by cladding material, said segment having opposed, longitudinally extending flats to provide reduced cladding thickness between the core and the surface of the flats for enhanching lateral coupling there at, and reflective means located at each of said end faces to effect an optical resonant cavity.

Claim 35

Dependent Claim 19 words

The cavity of claim 30 wherein said end faces of said segment are mirrored for providing said reflective means.

Claim 36

Dependent Claim 53 words

An optical waveguide cavity arrangement comprising at least a pair of resonant cavities formed of optical waveguides with the optical path of one of said cavities including a waveguide section forming a portion of the optical path of the other of said cavities whereby the resonance of each of said cavities is interrelated.

Claim 37

Dependent Claim 53 words

An optical waveguide cavity arrangement comprising at least a pair of resonant cavities formed of optical waveguides with the optical path of one of said cavities including a waveguide section forming a portion of the optical path of the other of said cavities whereby the resonance of each of said cavities is interrelated.

Claim 38

Dependent Claim 45 words

The cavity of claim 32 wherein said one cavity is a loop cavity formed by a waveguide segment coupled at spaced apart points to said waveguide section of said other cavity so as to form a closed loop which includes portions of said other cavity.

Claim 39

Dependent Claim 23 words

The cavity of claim 33 wherein said other cavity is also a resonant loop with said segment coupled to generally opposing sides thereof.

Claim 40

Dependent Claim 122 words

An optical filter system comprising an elongated input optical waveguide mounted in generally spaced parallel relation to an elongated output waveguide to define an elongated gap therebetween, a plurality of optical waveguide resonator arrangements located along said elongated gap and coupled to said input and output waveguides so as to transfer energy from said input to said output waveguide at the location of each resonator arrangement, and said resonator arrangements are located along said gap in relation to each other such that energy transferred to the output waveguide for travel in a backward direction opposite to the flow of energy in said input waveguide is different in phase from one resonator arrangement to another so as to reduce such backward flowing energy.

Claim 41

Dependent Claim 122 words

An optical filter system comprising an elongated input optical waveguide mounted in generally spaced parallel relation to an elongated output waveguide to define an elongated gap therebetween, a plurality of optical waveguide resonator arrangements located along said elongated gap and coupled to said input and output waveguides so as to transfer energy from said input to said output waveguide at the location of each resonator arrangement, and said resonator arrangements are located along said gap in relation to each other such that energy transferred to the output waveguide for travel in a backward direction opposite to the flow of energy in said input waveguide is different in phase from one resonator arrangement to another so as to reduce such backward flowing energy.

Claim 42

Dependent Claim 62 words

The system of claim 35 wherein the phase between energy transferred in a backward direction by a first resonator arrangement is displaced from that transferred by second resonator arrangement by approximately twice the phase length of the section of output waveguide between the couplings of said first and second resonator arrangements to provide destructive interference between the backward directed energy transferred thereby.

Claim 43

Dependent Claim 98 words

The system of claim 35 wherein said input and output waveguides are optical fibers, and said system includes a body for supporting linear portions of the output and input fibers in spaced parallel relation, said body carrying a longitudinal recess between said input and output fibers, and said system including means receivable in said recess for supporting said resonators adjustably along said slot, said means for supporting said resonators comprising a plurality of blocks having at least a portion conforming to and receivable in said slot with one of said resonators being supported in each said block portion.

Claim 44

Dependent Claim 53 words

The system of claim 37 wherein each said block portion has a pair of generally parallel end faces as measured along the axis of said reecess, a waveguide fiber extending between said end faces, and a mirror arrangement on said end faces to provide a linear resonant cavity extending within said block portion.

Claim 45

Dependent Claim 69 words

The system of claim 38 wherein said body provides a resonantor support surface adjoining an exterior end of said recess, and each said block is T-shaped, having a depending leg providing said block portion such that each said T-shaped block is configured to be supported on said resonator support surface of said body with its depending, resonator carrying leg carried within said slot for adjustment of its location therealong.

Claim 46

Dependent Claim 108 words

An optical filter system comprising an input optical waveguide, an output optical waveguide, a waveguide cavity resonator coupled to said input and output waveguides so as to transfer from said input to said output waveguide wavelengths resonant in said resonator, said resonator being laterally coupled to said output waveguide near a proximate end thereof such that transferred energy in said output waveguide is directed both toward and away from said proximate end, and said output waveguide including a reflective arrangement at its said proximate end to reflect energy directed toward said end to increase the energy in said output waveguide which is directed away from said proximate end.

Claim 47

Dependent Claim 108 words

An optical filter system comprising an input optical waveguide, an output optical waveguide, a waveguide cavity resonator coupled to said input and output waveguides so as to transfer from said input to said output waveguide wavelengths resonant in said resonator, said resonator being laterally coupled to said output waveguide near a proximate end thereof such that transferred energy in said output waveguide is directed both toward and away from said proximate end, and said output waveguide including a reflective arrangement at its said proximate end to reflect energy directed toward said end to increase the energy in said output waveguide which is directed away from said proximate end.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1991-01-18	1991-07-20	1992-01-19	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1995-01-18	1995-07-20	1996-01-19	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1999-01-18	1999-07-20	2000-01-19	$7700.00	Window Closed / Lapsed

Optical resonant cavity filters

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