WO2003007032A1 - Dispositif a reseau de diffraction de guide d'ondes optiques et procede de fabrication correspondant - Google Patents
Dispositif a reseau de diffraction de guide d'ondes optiques et procede de fabrication correspondant Download PDFInfo
- Publication number
- WO2003007032A1 WO2003007032A1 PCT/JP2002/006868 JP0206868W WO03007032A1 WO 2003007032 A1 WO2003007032 A1 WO 2003007032A1 JP 0206868 W JP0206868 W JP 0206868W WO 03007032 A1 WO03007032 A1 WO 03007032A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- refractive index
- optical waveguide
- diffraction grating
- optical axis
- index modulation
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
- G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
- G02B6/02123—Refractive index modulation gratings, e.g. Bragg gratings characterised by the method of manufacture of the grating
- G02B6/02133—Refractive index modulation gratings, e.g. Bragg gratings characterised by the method of manufacture of the grating using beam interference
- G02B6/02138—Refractive index modulation gratings, e.g. Bragg gratings characterised by the method of manufacture of the grating using beam interference based on illuminating a phase mask
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
- G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
- G02B6/0208—Refractive index modulation gratings, e.g. Bragg gratings characterised by their structure, wavelength response
- G02B6/02085—Refractive index modulation gratings, e.g. Bragg gratings characterised by their structure, wavelength response characterised by the grating profile, e.g. chirped, apodised, tilted, helical
Definitions
- the present invention relates to an optical waveguide type diffraction grating device having a refractive index modulation portion formed along the longitudinal direction of an optical waveguide, and a method for manufacturing the same.
- the optical waveguide type diffraction grating element has a refractive index modulation portion formed over a predetermined range along the longitudinal direction of an optical waveguide (for example, an optical fiber).
- an optical waveguide for example, an optical fiber.
- a straight line perpendicular to the refractive index equalizing surface is parallel to the optical axis of the optical waveguide.
- the index modulation period is
- the light having the reflection wavelength ⁇ reflected by the refractive index modulation section propagates through the optical waveguide in a direction opposite to that at the time of incidence.
- an optical waveguide type diffraction grating element (hereinafter, referred to as an “inclined type diffraction grating element”) in which a straight line perpendicular to the refractive index equipotential plane is not parallel to the optical axis of the optical waveguide (for example, References: M. J. Holmes, et al., "Ultra Narrow-Band Optical Fiber Sidetap Filters", ECOC '98, pp. 137-138 (1998)).
- 1A and IB are explanatory diagrams of a conventional tilted diffraction grating device.
- FIG. 1A is a cross-sectional view taken along a plane including the optical axis of the tilted diffraction grating element
- FIG. 1B is a cross-sectional view taken along a plane perpendicular to the optical axis.
- the conventional tilted diffraction grating element 9 shown in this figure is an optical fiber 90 having a high-refractive-index core region 91 and a low-refractive-index cladding region 92.
- the refractive index modulator 93 is formed over a predetermined range along the axis.
- a straight line A perpendicular to the refractive index isotropic plane L in the refractive index modulation section 93 is parallel to the optical axis of the optical fiber 90 (the X axis in the figure). And the angle ⁇ between the straight line A and the optical axis is not zero.
- the light having the reflection wavelength ⁇ reflected by the refractive index modulator 93 is radiated outside the optical fiber 90 without propagating through the optical fiber 90. That is, the tilt type diffraction grating element 9 functions as a low reflection loss filter. Therefore, the tilt type diffraction grating element 9 can be suitably used, for example, as a gain equalizer for equalizing the gain of an optical fiber amplifier.
- the loss characteristics of the conventional tilted diffraction grating element 9 have polarization dependence. That is, a polarization mode having a polarization plane parallel to the polarization plane ⁇ (the Xy plane in FIGS. 11A and 11B) formed by the straight line ⁇ and the optical axis, and a polarization mode perpendicular to the polarization plane M.
- the loss characteristics are different from those of the polarization mode having a wavefront.
- the optical fiber is made of glass and is fragile.
- the refractive index modulation section must be long. is necessary.
- an extra length section is required for fusion splicing, so that the entire refractive index modulation section becomes long.
- the conventional tilt type diffraction grating element is short and cannot reduce the polarization dependent loss.
- the present invention has been made to solve the above problems, and has been made in consideration of an optical waveguide type diffraction grating. It is an object of the present invention to provide a slave element (inclined diffraction grating element) and a method for manufacturing the same. Disclosure of the invention
- N is an integer not smaller than 2 refractive index modulation section
- N is an integer not smaller than 2 refractive index modulation section
- N pieces of The straight line perpendicular to the refractive index equalization plane of each of the refractive index modulation sections is not parallel to the optical axis of the optical waveguide
- 3 ) the straight line perpendicular to the refractive index equalization plane of each of the N refractive index modulation sections is The declination planes formed by the optical axis of the waveguide do not coincide with each other, and (4) at least a part of the formation regions of any two of the N refractive index modulation portions overlap each other. It is characterized by
- the method of manufacturing an optical waveguide type diffraction grating device comprises the steps of: (1) N (N is an integer of 2 or more) refractive index modulating sections along the longitudinal direction of the optical waveguide perpendicular to the refractive index equal plane. In addition, di and di are not formed in parallel with the optical axis of the optical waveguide and are sequentially formed.
- N N is an integer of 2 or more
- di and di are not formed in parallel with the optical axis of the optical waveguide and are sequentially formed.
- optical waveguide type diffraction grating element is manufactured such that the formation regions of any two of the N refractive index modulating portions at least partially overlap each other. I do.
- the optical waveguide type diffraction grating device according to the present invention and the optical waveguide type diffraction grating device manufactured by the optical waveguide type diffraction grating device manufacturing method according to the present invention, have an even refractive index modulation portion.
- the straight line perpendicular to the refractive index equipotential surface of each refractive index modulating section is not parallel to the optical axis of the optical waveguide, and the deflector planes of each refractive index modulating section do not match each other. At least a part of the formation region of each of the modulation portions overlaps each other. With this configuration, the optical waveguide type diffraction grating element is short and has reduced polarization dependent loss.
- the optical waveguide type diffraction grating element according to the present invention has N refractive index modulating portions. Are deviated by 180 degrees / N around the optical axis of the optical waveguide.
- the method of manufacturing an optical waveguide type diffraction grating device according to the present invention comprises the steps of: shifting the deflected surface of each of the N refractive index modulation portions by 180 degrees ZN around the optical axis of the optical waveguide; It is characterized in that a grating element is manufactured.
- the optical waveguide type diffraction grating element is one in which the polarization dependent loss is efficiently reduced.
- the optical waveguide type diffraction grating element according to the present invention is characterized in that the deflector planes of the N refractive index modulation portions are shifted by 360 ° ZN around the optical axis of the optical waveguide.
- the method of manufacturing an optical waveguide type diffraction grating device according to the present invention comprises the steps of: shifting the declination plane of each of the N refractive index modulation portions by 360 ° / N around the optical axis of the optical waveguide; It is characterized in that a diffraction grating element is manufactured.
- N may be an odd number, but is preferably an even number. If N is an even number, the birefringence due to the non-axial symmetry of each pair of the refractive index modulators whose declination planes differ by 180 degrees from each other is canceled out. In the optical waveguide type diffraction grating element, the polarization dependent loss is further reduced efficiently.
- each of the N refractive index modulating portions has the same angle between a straight line perpendicular to the refractive index equalizing surface and the optical axis of the optical waveguide.
- the lengths of the formation regions along the longitudinal direction of the optical waveguide are the same, the refractive index modulation periods are the same, and the refractive index modulation amplitudes are the same.
- the method for manufacturing an optical waveguide type diffraction grating device is characterized in that, when forming each of the N refractive index modulating portions, an angle formed between a straight line perpendicular to the refractive index isotope plane and the optical axis of the optical waveguide.
- the characteristics are the same, the lengths of the formation regions along the longitudinal direction of the optical waveguide are the same, the refractive index modulation periods are the same, and the refractive index modulation amplitudes are the same.
- the optical waveguide type diffraction grating element is one in which the polarization dependent loss is efficiently reduced.
- the optical waveguide type diffraction grating element according to the present invention is characterized in that the polarization dependent loss is 1/10 or less of the maximum transmission loss at the wavelength where the transmission loss is maximum.
- the optical waveguide type diffraction grating element is suitably used as an optical device (or a part thereof) which is required to have a small polarization dependent loss in the field of optical communication.
- each of the N refractive index modulation portions is formed while monitoring transmission loss.
- each of the N refractive index modulators is formed while monitoring the polarization dependent loss.
- the manufactured optical waveguide type diffraction grating element has the polarization dependent loss reduced efficiently.
- FIGS. 1A and 1B are explanatory diagrams of a conventional tilted diffraction grating element.
- FIG. 2 is an explanatory diagram of the optical waveguide type diffraction grating device (tilted diffraction grating device) according to the present embodiment.
- FIG. 3 is a perspective view for explaining the optical waveguide type diffraction grating device manufacturing method according to the present embodiment.
- FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D are cross-sectional views for explaining the optical waveguide type diffraction grating device manufacturing method according to the present embodiment.
- FIGS. 5A and 5B are diagrams showing the transmission characteristics of the optical waveguide type diffraction grating device (tilted type diffraction grating device) of the present embodiment.
- FIG. 5A shows the completion of the formation of the first refractive index modulation section.
- FIG. 5B is a diagram illustrating transmission characteristics at a time point, and
- FIG. 5B is a diagram illustrating transmission characteristics at a time point when the formation of the second refractive index modulation section is completed.
- FIGS. 6A and 6B are diagrams showing the transmission characteristics and polarization dependent loss characteristics of the optical waveguide type diffraction grating device (tilted diffraction grating device) of the present example, respectively.
- FIGS. 7A and 7B are diagrams showing transmission characteristics and polarization dependent loss characteristics of the optical waveguide type diffraction grating device (tilted diffraction grating device) of the comparative example, respectively.
- FIG. 8 shows an optical waveguide type diffraction grating device (tilt type diffraction grating device) according to another embodiment.
- FIG. 8 shows an optical waveguide type diffraction grating device (tilt type diffraction grating device) according to another embodiment.
- 9A and 9B show the transmittance T and the polarization-dependent loss PDL of the tilted diffraction grating element in which the refractive index change inducing light is irradiated from only one direction to form one refractive index modulation unit.
- 4 is a graph showing wavelength dependence.
- 1OA and 1OB are the transmittance T and the polarization of the tilted diffraction grating element 1 in which two refractive index modulating portions are formed by irradiating the refractive index change inducing light from two directions different from each other by 90 degrees.
- 6 is a graph showing the wavelength dependence of each dependent loss PDL.
- FIGS. 11A and 11B show the transmittance of the tilted diffraction grating element 2 having four refractive index modulation portions formed by irradiating the refractive index change inducing light from four directions different from each other by 90 degrees.
- 9 is a graph showing the wavelength dependence of each of T and polarization dependent loss PDL.
- FIG. 2 is an explanatory diagram of an optical waveguide type diffraction grating device (tilted diffraction grating device) 1 according to the present embodiment.
- a cross-sectional view taken along a plane including the optical axis and a cross-sectional view taken along a plane perpendicular to the optical axis are shown.
- the inclined diffraction grating element 1 has N (N is an integer of 2 or more) refractive index modulation sections along the longitudinal direction of the optical fiber 10 as an optical waveguide. 13 to 13 N are formed.
- Optical fiber 1 0 includes a one that the quartz glass base, and the core region 1 1 G e 0 2 is added, and a cladding region 1 2 surrounding the core region 1 1.
- the refractive index isotropic surface is denoted by L n, and is perpendicular to the refractive index isotropic surface L n .
- the straight line intersects the optical fiber 1 0 of the optical axis (X-axis) represents the a n there, represents the angle formed by the straight line a n and the optical axis and theta eta, linear Alpha eta and declination plane and the optical axis forms the representative of the ⁇ ⁇ .
- each refractive index modulation section 1 3 eta in which the refractive index modulation in a linear Alpha eta inclined by an angle theta eta respect to the optical axis along connection period lambda eta is formed in Koa region 1 1. Also, the declination plane of each refractive index modulating unit 13 ⁇ ! ⁇ . Do not match each other.
- any two of the refractive index modulation section 1 3 nl, 1 3 n2 each formation region of the N refractive index modulation unit 1 3i ⁇ l 3 N overlaps at least a part from one another.
- forming region of the refractive index modulation unit 1 3A_ are partially overlapped and forming region of the refractive index modulation section 1 3 2, partially overlaps with formation region of the refractive index modulation section 1 3 3 and which, also, it is partially overlapped with formation region of the refractive index modulation section 1 3 N.
- the N refractive index modulating sections 1 Sil 3 N are formed, and the angle ⁇ ⁇ of each refractive index modulating section 13 n is 0. without no declination surface Micromax eta each refractive index modulation section 1 3 eta coincide with each other, any two of the refractive index modulation section 1 3 ⁇ 1, 1 3 ⁇ 2 is at least a portion each forming regions from each other overlapping.
- the tilt type diffraction grating element 1 configured as described above is short and has reduced polarization dependent loss.
- each of the ⁇ refractive index modulation sections 13i to l3 1 ⁇ be deflected by 180 ° / N around the optical axis of the optical fiber 10 for each of the declination planes 1 to ⁇ . is there.
- N 2
- the deflected plane Mi Ms is shifted by 60 degrees around the optical axis of the optical fiber 10.
- each of the N refractive index modulation unit 1 3i ⁇ l 3 N, straight / sickle A n and the angle between the optical axis theta eta are the same and, in the formation region along the longitudinal direction of the optical fiber 10 length
- D n are the same
- the refractive index modulation periods are the same
- the refractive index modulation amplitudes are the same.
- the polarization dependent loss is 1 Z 10 or less of the maximum value of the transmission loss at the wavelength where the transmission loss is the maximum.
- Such a tilted diffraction grating element 1 is suitably used as an optical device (or a part thereof) which is required to have a small polarization dependent loss in the field of optical communication.
- the gain of an optical fiber amplifier is equalized. It can be suitably used as a gain equalizer that performs
- FIGS. 3 and 4A to 4D are views for explaining the method of manufacturing the optical waveguide type diffraction grating element according to the present embodiment.
- FIG. 3 is a perspective view
- FIGS. 4A to 4D are cross-sectional views taken along a plane perpendicular to the optical axis.
- an optical fiber 10, a phase grating mask 20, and a light source 30 are prepared.
- the optical fiber 10 is based on quartz glass,
- the phase grating mask 20 is formed by forming a phase grating composed of groove-like irregularities with a period of 2 mm on one surface of a quartz glass flat plate.
- the light source 30 outputs light having a wavelength that induces a change in the refractive index of the core region 11 of the optical fiber 10 (hereinafter referred to as “refractive index change-inducing light”).
- a KrF excimer laser light source that outputs n ni laser light as refractive index change inducing light is used.
- the phase grating mask 20 is arranged on the side of the optical fiber 10 such that the surface on which the phase grating is formed faces the optical fiber 10. At this time, the direction of the groove in the phase grating of the phase grating mask 20 is
- the refractive index change inducing light UV output from the light source 30 is irradiated perpendicularly to the phase grating mask 20. Due to the irradiation of the refractive index change inducing light UV, the diffraction action of the phase grating mask 20 generates + 1st-order and 1st-order diffraction lights, and these + 1st-order and 1st-order diffraction lights interfere with each other. Then, an interference fringe having a period ⁇ is generated.
- the refractive index modulating section 1 is defined as follows: When a straight line perpendicular to the refractive index isotropic plane 1 ⁇ and intersecting with the optical axis of the optical fiber 10 is represented by A, the angle between the straight line and the optical axis is Si. And the declination plane formed by the straight line and the optical axis is parallel to the plane of the phase grating mask 20 (see FIGS. 3 and 4A).
- the first refractive index modulation section 13 is formed by irradiating the refractive index change inducing light UV for a fixed time in the arrangement state shown in FIG. 4A.
- the irradiation of the refractive index change inducing light UV is interrupted, and during that time, the optical fiber 10 is rotated around the optical axis by a certain angle, and the arrangement state shown in FIG. 4B is obtained.
- 4 refractive index modulation section 1 3 2 of the second by being irradiated only between the refractive index change inducing light UV gar scheduled in the arrangement state shown in B is formed.
- the first second refractive index modulation section 1 3 2 formed by a straight line intersecting a perpendicular to the refractive index or the like proximal surface L 2 and the optical axis of the optical fiber 1 0 is taken as A 2
- the angle formed by the straight line A 2 and the optical axis is ⁇ 2
- the declination plane ⁇ 2 formed by the straight line ⁇ 2 and the optical axis is parallel to the plane of the phase grating mask 20.
- Declination surface Micromax 2 of the second refractive index modulation section 1 3 2 no longer coincide with the deflection angle plane Mi of the first refractive index modulation section 1 3 E formed.
- Third refractive index modulation section 1 3 3 formed in this manner, bending Assuming that a straight line perpendicular to the refractive index equipotential plane L 3 and intersecting the optical axis of the optical fiber 10 is A 3 , the angle between the straight line A 3 and the optical axis is ⁇ 3 , and the straight line ⁇ An angle plane 3 formed by 3 and the optical axis is parallel to the plane of the phase grating mask 20. Third refractive index modulation section 1 3 3 declination surface Micromax 3 of is not already match the polarization angle surface of the first refractive index modulation section 1 3 formed, also already formed the second refractive index modulation section 1 3 2 do not match both declination plane M 2.
- second N-th refractive index modulation unit 1 3 4 to 1 3 N are sequentially formed.
- the N-th refractive index modulation section 1 3 N is the N-th refractive index in the refractive index change inducing light UV with placement state shown in FIG. 4 D is irradiated for a certain time
- a modulation section 13N is formed.
- N-th refractive index modulation section 1 3 N formed in this way, a straight line intersecting a perpendicular to the refractive index or the like proximal surface L N to the optical axis of the optical fiber 1 0 is taken as A N, the straight line a N and the angle between the optical axis is the theta New, declination plane formed by the straight line Alpha New and the optical axis Micromax New is parallel to the plane of the phase grating mask 2 0.
- the declination plane ⁇ ⁇ of the ⁇ th refractive index modulator 13 ⁇ is the first to ( ⁇ — 1) th refractive index modulators 13 31 to 1 ⁇ ⁇ already formed. Does not match any of the above.
- each ⁇ ⁇ has the same value.For each force S, each ⁇ ⁇ is different because the phase grating mask 20 is rotated on its surface. be able to. Further, one be employed as a phase grating mask 2 0, all the refractive index modulation periods along line Alpha eta at each refractive index modulation section 1 3 eta is the same value, different phase grating mask of the phase grating period by being exchanged, ⁇ Tsuta refractive index modulation period in a linear Alpha eta at each refractive index modulation section 1 3 eta may be different in.
- the straight lines ⁇ ⁇ perpendicular to n are sequentially formed so that they are not parallel to the optical axis of the optical fiber 10 (that is, the angle ⁇ ⁇ ⁇ 0).
- the formation regions of any two of the N refractive index modulation sections 1 to 3N are formed such that at least a part thereof overlaps each other.
- the tilted diffraction grating element 1 according to the present embodiment is manufactured.
- the optical fiber 10 is rotated around the optical axis by a fixed angle of 18 O ZN after the (n-1) th refractive index modulation section 13-is formed, and the nth refractive index modulation is performed.
- the part 13 n is formed.
- the tilt type diffraction grating element 1 manufactured as described above has a structure in which the deflector planes ⁇ N of the N refractive index modulators 13 i to l 3 N are arranged around the optical axis of the optical fiber 10. Since it is shifted by 80 degrees, the polarization-dependent loss is efficiently reduced.
- the tilt type diffraction grating element 1 manufactured in this manner has a polarization-dependent loss that is efficiently reduced.
- each of the refractive index modulators 13 n it is preferable to monitor the transmission loss or the polarization dependent loss of the tilted diffraction grating element 1 during the manufacture. By doing so, the polarization-dependent loss in the manufactured tilted diffraction grating element 1 is efficiently reduced.
- the optical waveguide type diffraction grating element (tilted type diffraction grating element) 1 according to the present embodiment and a method of manufacturing the same will be described.
- the optical fiber 1 0 been filed in which G e 0 2 in the cladding region 1 2 not only Koa region 1 1 is added.
- the period is not constant, but changes gradually along the direction perpendicular to the groove direction, the center period is 1.065 6 ⁇ , and the period change rate is 1 0. It was OnmZcm.
- the light source 30 used was a KrF excimer laser light source that outputs laser light having a wavelength of 248 nm as refractive index change inducing light.
- the manufactured tilted diffraction grating element 1 of the present example had two refractive index modulating sections 13 1 ⁇ 13 2 . 1 3 2 each of the two refractive index modulation unit 1 3h, the length of the forming area is 5 mm, formed by superposed each other at all.
- the deflection angle plane of the refractive index modulation section 1 3 ⁇ and declination surface M 2 of the refractive index modulation section 1 3 2 was also of the mutually orthogonal.
- the first refractive index modulation section 13i is formed, and thereafter, while the irradiation of the refractive index change inducing light UV is interrupted, the optical fiber 10 is moved by 90 degrees along the optical axis. It is rotated about, followed by a second refractive index modulation section 1 3 2 are formed. Further, at the time of forming each of the two refractive index modulation portions 13 13 32, the transmission loss of the tilted diffraction grating element 1 during the manufacturing was monitored.
- the target value of the transmission loss at the wavelength at which the transmission loss is the maximum is 1 dB. Then, when the first refractive index modulation section 13 is formed, when the monitored transmission loss becomes 1/2 (0.5 dB) of the target value, the refractive index change inducing light UV Irradiation was interrupted. Further, subsequent to the time of the second refractive index forming the modulation unit 13 2, when the monitored transmission loss became the target value (l dB), is terminated irradiation of the refractive index change induced Okoshiko UV Was.
- FIG. 5A is a graph showing the transmission characteristics of the formation termination point of the first refractive index modulation section 1 3 ⁇ , Figure 5B, at the second refractive index modulation section 1 3 2 forming end
- FIG. 4 is a diagram showing transmission characteristics of the hologram.
- the maximum value of the transmission loss of the inclined grating element 1 of this embodiment is a 0. 5 dB in the first forming end of the refractive index modulation section 1 3 1, the At the end of the formation of the second refractive index modulation section 132, it was 1.0 dB.
- FIG. 6A is a diagram illustrating transmission characteristics of the tilted diffraction grating element of the present embodiment
- FIG. 6B is a diagram illustrating polarization dependent loss characteristics of the tilted diffraction grating device of the present embodiment
- FIG. 7A is a diagram showing transmission characteristics of the tilted diffraction grating element of the comparative example
- FIG. It is a figure which shows the polarization dependent loss characteristic of the inclination type diffraction grating element of a comparative example.
- the tilt type diffraction grating element of the comparative example had only one refractive index modulation section without being overwritten .
- the tilted diffraction grating element of the present example and the tilted diffraction grating element of the comparative example each have a similar transmission spectrum shape, and In each case, the maximum value of the transmission loss was about 0.6 dB. However, as can be seen by comparing FIG. 6B and FIG. 7B, the maximum value of the polarization dependent loss of the tilted diffraction grating element of the comparative example is about 0.125 dB. The maximum value of the polarization dependent loss of the tilted diffraction grating element of this example was about 0.03 dB.
- the maximum value of the polarization dependent loss of the tilted diffraction grating element of the present example is about 1/4 compared to the maximum value of the polarization dependent loss of the tilted diffraction grating element of the comparative example.
- the transmission loss was about 1/20 compared with the maximum value of the transmission loss of the tilted diffraction grating element of the example.
- FIG. 8 is an explanatory diagram of an optical waveguide type diffraction grating device (tilted diffraction grating device) 2 according to another embodiment.
- This figure shows a cross-sectional view when cut along a plane including the optical axis and a cross-sectional view when cut along a plane perpendicular to the optical axis.
- the inclined diffraction grating element 2 according to the present embodiment shown in this figure has N (N is an integer of 2 or more) refractive index modulation sections along the longitudinal direction of the optical fiber 20 as an optical waveguide.
- 23 i to 23 N are formed.
- Optical fiber 2 0 includes a one that the quartz glass base, a core region 2 1 G E_ ⁇ 2 is added, and a cladding region 2 2 surrounding the core region 2 1.
- the refractive index isotropic surface is denoted by L n, and the refractive index is perpendicular to the refractive index isotropic surface L n .
- the straight line intersects the optical fiber 2 0 of the optical axis (X-axis) represents the a n there, represents the angle formed by the straight line a n and the optical axis and theta eta, linear Alpha eta and declination plane and the optical axis forms And.
- each refractive index modulating section 23 n The formation region of each refractive index modulating section 23 n , the refractive index equipotential surface L n , the straight line An, and the angle ⁇ ⁇ are as described above.
- the optical waveguide type diffraction grating element 2 further has The polarization dependent loss is reduced efficiently.
- the non-axial symmetry referred to here means that the refractive index modulation section 23 formed by irradiating the optical fiber 20 with the refractive index change inducing light has a refractive index on the incident side of the refractive index change inducing light. Say that the rise is getting bigger.
- This tilted diffraction grating element 2 also preferably has a polarization dependent loss of 1/10 or less of the maximum transmission loss at the wavelength where the transmission loss is maximum.
- Such a tilted diffraction grating element 2 is also suitably used as an optical device (or a part thereof) that is required to have a small polarization dependent loss in the field of optical communication.
- the gain of an optical fiber amplifier is equalized. It can be suitably used as a gain equalizer that performs
- FIGS. 9A to 11B are graphs showing the wavelength dependence of the transmittance T and the polarization dependent loss PDL of three types of tilted [II-fold grating elements, respectively.
- FIGS. 9A and 9B show an oblique diagonal diffraction grating element in which one refractive index modulation section is formed by irradiating the refractive index change inducing light only from one direction.
- FIGS. 9A and 9B show the tilted diffraction grating element 1 in which two refractive index modulating portions are formed by irradiating the refractive index change inducing light from two directions different from each other by 90 degrees.
- FIGS. 11A and 11B show an inclined diffraction grating element 2 in which four refractive index modulating portions are formed by irradiating refractive index change inducing light from four directions different from each other by 90 degrees.
- Each of the tilt type diffraction grating elements 1 and 2 has a refractive index modulation
- the wavelength dependence of the transmittance T of each of the three types of tilted diffraction grating elements was substantially the same.
- the polarization dependent loss PDL of the tilted diffraction grating element with one refractive index modulation section reached 0.127 dB.
- the polarization dependent loss PDL of the tilted diffraction grating element 1 was as small as 0.023 dB, and the polarization dependent loss PDL of the tilted diffraction grating element 2 was even smaller as 0.016 dB.
- N is an integer of 2 or more refractive index modulating portions are formed, and a straight line perpendicular to the refractive index equipotential surface of each refractive index modulating portion is formed.
- the deflected surfaces of the respective refractive index modulators do not coincide with each other, and the formation regions of any two refractive index modulators at least partially overlap each other .
- the optical waveguide type diffraction grating element thus configured is short and has a reduced polarization dependent loss.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Diffracting Gratings Or Hologram Optical Elements (AREA)
- Optical Integrated Circuits (AREA)
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR10-2003-7003393A KR20030026364A (ko) | 2001-07-10 | 2002-07-05 | 광도파로형 회절 격자 소자 및 그 제조방법 |
EP02741421A EP1406098A4 (en) | 2001-07-10 | 2002-07-05 | OPTICAL SHAFT BENDING GRILLE ELEMENT AND METHOD FOR THE PRODUCTION THEREOF |
JP2003512743A JPWO2003007032A1 (ja) | 2001-07-10 | 2002-07-05 | 光導波路型回折格子素子およびその製造方法 |
CA002453533A CA2453533A1 (en) | 2001-07-10 | 2002-07-05 | Optical waveguide diffraction grating device and its fabrication method |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001-209826 | 2001-07-10 | ||
JP2001209826 | 2001-07-10 | ||
JP2002-012017 | 2002-01-21 | ||
JP2002012017 | 2002-01-21 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2003007032A1 true WO2003007032A1 (fr) | 2003-01-23 |
Family
ID=26618465
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2002/006868 WO2003007032A1 (fr) | 2001-07-10 | 2002-07-05 | Dispositif a reseau de diffraction de guide d'ondes optiques et procede de fabrication correspondant |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP1406098A4 (ja) |
JP (1) | JPWO2003007032A1 (ja) |
KR (1) | KR20030026364A (ja) |
CN (1) | CN1526079A (ja) |
CA (1) | CA2453533A1 (ja) |
TW (1) | TW550400B (ja) |
WO (1) | WO2003007032A1 (ja) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7946137B2 (en) | 2002-01-02 | 2011-05-24 | United Technologies Corporation | Long period fiber Bragg gratings written with alternate side IR laser illumination |
CN112601990A (zh) * | 2018-03-13 | 2021-04-02 | 交互数字Ce专利控股公司 | 包括双材料结构的衍射光栅 |
US11604363B2 (en) | 2018-03-13 | 2023-03-14 | Interdigital Ce Patent Holdings | Image sensor comprising a color splitter with two different refractive indexes |
US11972508B2 (en) | 2018-07-02 | 2024-04-30 | Interdigital Ce Patent Holdings, Sas | Image sensor comprising a color splitter with two different refractive indexes, and different height |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102183488B (zh) * | 2011-03-04 | 2013-06-19 | 北京交通大学 | 基于闪耀长周期光纤光栅的折射率传感器 |
JP6460637B2 (ja) * | 2014-03-31 | 2019-01-30 | 富士通株式会社 | 半導体光導波路装置 |
CN104777535B (zh) * | 2015-03-25 | 2017-05-24 | 东南大学 | 一种复用体全息光栅 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0672922A2 (en) * | 1994-02-17 | 1995-09-20 | AT&T Corp. | Method of controlling polarization properties of a photo-induced device in an optical waveguide and method of investigating structure of an optical waveguide |
JPH1184117A (ja) * | 1997-09-09 | 1999-03-26 | Fujikura Ltd | 反射型光導波路グレーティング |
JP2000266945A (ja) * | 1999-01-25 | 2000-09-29 | Alcatel | 傾斜および線形チャープを有するフィルタ光導波路 |
JP2001021738A (ja) * | 1999-07-12 | 2001-01-26 | Sumitomo Electric Ind Ltd | 光導波路型フィルタ及びその製造方法並びに光ファイバ増幅器 |
EP1111415A1 (en) * | 1999-12-21 | 2001-06-27 | Agilent Technologies, Inc., a corporation of the State of Delaware | Process and device for making gratings in optical fibres |
-
2002
- 2002-07-05 CN CNA028137426A patent/CN1526079A/zh active Pending
- 2002-07-05 WO PCT/JP2002/006868 patent/WO2003007032A1/ja not_active Application Discontinuation
- 2002-07-05 CA CA002453533A patent/CA2453533A1/en not_active Abandoned
- 2002-07-05 JP JP2003512743A patent/JPWO2003007032A1/ja active Pending
- 2002-07-05 KR KR10-2003-7003393A patent/KR20030026364A/ko not_active Application Discontinuation
- 2002-07-05 EP EP02741421A patent/EP1406098A4/en not_active Withdrawn
- 2002-07-08 TW TW091115062A patent/TW550400B/zh not_active IP Right Cessation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0672922A2 (en) * | 1994-02-17 | 1995-09-20 | AT&T Corp. | Method of controlling polarization properties of a photo-induced device in an optical waveguide and method of investigating structure of an optical waveguide |
JPH1184117A (ja) * | 1997-09-09 | 1999-03-26 | Fujikura Ltd | 反射型光導波路グレーティング |
JP2000266945A (ja) * | 1999-01-25 | 2000-09-29 | Alcatel | 傾斜および線形チャープを有するフィルタ光導波路 |
JP2001021738A (ja) * | 1999-07-12 | 2001-01-26 | Sumitomo Electric Ind Ltd | 光導波路型フィルタ及びその製造方法並びに光ファイバ増幅器 |
EP1111415A1 (en) * | 1999-12-21 | 2001-06-27 | Agilent Technologies, Inc., a corporation of the State of Delaware | Process and device for making gratings in optical fibres |
Non-Patent Citations (3)
Title |
---|
HOLMES M.J. ET AL.: "Ultra narrow-band optical fibre sidetap filters", 24TH EUROPEAN CONFERENCE ON OPTICAL COMMUNICATION, vol. 1, 20 September 1998 (1998-09-20) - 24 September 1998 (1998-09-24), MADRID, SPAIN, pages 137 - 138, XP000858670 * |
See also references of EP1406098A4 * |
WESTBROOK P.S., STRASSER T.A., ERDOGAN T.: "In-line polarimeter using blazed fiber gratings", IEEE PHOTONICS TECHNOLOGY LETTERS, vol. 12, no. 10, October 2000 (2000-10-01), pages 1352 - 1354, XP000970132 * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7946137B2 (en) | 2002-01-02 | 2011-05-24 | United Technologies Corporation | Long period fiber Bragg gratings written with alternate side IR laser illumination |
CN112601990A (zh) * | 2018-03-13 | 2021-04-02 | 交互数字Ce专利控股公司 | 包括双材料结构的衍射光栅 |
US11573356B2 (en) | 2018-03-13 | 2023-02-07 | Interdigital Ce Patent Holdings | Diffraction grating comprising double-materials structures |
US11604363B2 (en) | 2018-03-13 | 2023-03-14 | Interdigital Ce Patent Holdings | Image sensor comprising a color splitter with two different refractive indexes |
US11972508B2 (en) | 2018-07-02 | 2024-04-30 | Interdigital Ce Patent Holdings, Sas | Image sensor comprising a color splitter with two different refractive indexes, and different height |
Also Published As
Publication number | Publication date |
---|---|
TW550400B (en) | 2003-09-01 |
KR20030026364A (ko) | 2003-03-31 |
JPWO2003007032A1 (ja) | 2004-11-04 |
EP1406098A1 (en) | 2004-04-07 |
CA2453533A1 (en) | 2003-01-23 |
EP1406098A4 (en) | 2005-09-21 |
CN1526079A (zh) | 2004-09-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP3377728B2 (ja) | 光導波路からなる装置 | |
US6430342B1 (en) | Fiber grating and fiber optic devices using the same | |
US7376307B2 (en) | Multimode long period fiber bragg grating machined by ultrafast laser direct writing | |
US7340132B2 (en) | Polarization insensitive microbend fiber gratings and devices using the same | |
US7515803B2 (en) | Optical element, manufacturing method thereof, and optical device | |
US9696476B1 (en) | Volume Moiré Bragg gratings in a photosensitive material | |
CA2240903A1 (en) | Multi-path interference filter | |
EP1195633B1 (en) | Optical transmission module and optical communication system using the same | |
WO2003007032A1 (fr) | Dispositif a reseau de diffraction de guide d'ondes optiques et procede de fabrication correspondant | |
US6411755B1 (en) | Cladding-assisted single-mode fiber coupler | |
JP2002169028A (ja) | 光損失フィルタ | |
EP2224269A1 (en) | Optical waveguide-type wavelength dispersion compensation device and manufacturing method thereof | |
JPH1184117A (ja) | 反射型光導波路グレーティング | |
US6278817B1 (en) | Asymmetric low dispersion bragg grating filter | |
JP2002530691A (ja) | 光デバイスおよび方法 | |
TW569041B (en) | Reflection-grid optical waveguide-path type and its production method | |
JPH1090546A (ja) | 平面導波路の製造方法及び平面導波路 | |
JP3011140B2 (ja) | ファイバ型光アイソレータ及びその製造方法 | |
WO2022130515A1 (ja) | 三次元ハイブリッド光導波路およびその製造方法 | |
AU777481B2 (en) | Optical waveguide structure | |
JP4437951B2 (ja) | 光ファイバグレーティングの製造装置および製造方法 | |
US20040252944A1 (en) | Apparatus and method of manufacturing optical waveguide type diffraction grating device | |
CN115248473A (zh) | 基于飞秒激光刻写技术的可调谐光纤布拉格光栅的制备方法 | |
JP2001051134A (ja) | 光導波路型フィルタおよび光ファイバ増幅器 | |
JP2002169048A (ja) | 自己導波光回路 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AU CA CN JP KR |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LU MC NL PT SE SK TR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1020037003393 Country of ref document: KR |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWP | Wipo information: published in national office |
Ref document number: 1020037003393 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002741421 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2003512743 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 20028137426 Country of ref document: CN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002315792 Country of ref document: AU Ref document number: 2453533 Country of ref document: CA |
|
WWP | Wipo information: published in national office |
Ref document number: 2002741421 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 2002741421 Country of ref document: EP |