DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Response to Amendment
The following addresses applicant’s remarks/amendments dated 1 July 2026.
The amendment is sufficient to overcome the rejection of claim 4 under 35 U.S.C. 112(d).
Claims 1, 4, 6-9, were amended. Claim 2 was cancelled. Claims 3, 12-13, and 15-16 were previously withdrawn. New claim 17 was added. Therefore, claims 1, 4-11, 14, and 17 are currently pending in the current application and are addressed below.
Response to Arguments
Applicant’s arguments, see Remarks, filed 1 July 2026, with respect to the rejection of claim 1 under 35 U.S.C. 102 have been fully considered and are persuasive. Therefore, the rejection has been withdrawn. However, upon further consideration, a new ground of rejection is made in view of Seo et al., US 20060126161 A1 in view of Aozasa et al., US 20220344888 A1.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the appliSecation indicating obviousness or nonobviousness.
Claims 1, 4-9, and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Seo et al., US 20060126161 A1 (“Seo”) in view of Aozasa et al., US 20220344888 A1 (“Aozasa”).
Regarding claim 1, Seo discloses an optical fiber amplifier that amplifies a plurality of wavelength bands (Fig. 1, optical fiber 1, Paragraph [0034]), the optical fiber amplifier comprises
a rare-earth-doped optical fiber (Fig. 1, optical fiber 1, Paragraph [0033], [0035]), wherein a cross-section of the rare-earth-doped optical fiber comprises a main propagation region for signal light (Fig. 1, optical fiber 1, core 10 Paragraph [0033]), and a doped region doped with rare-earth ions, and the doped region exists other than the propagation region (Fig. 1, optical fiber 1, cladding 20 Paragraph [0033]); and […].
Seo does not teach: wherein the rare-earth-doped optical fiber is divided into a plurality of sections, and an arrangement of the doped region is different for each of the sections and the doped region in one of the sections is configured to amplify a C-band signal, and the doped region in another of the sections is configured to amplify an L-band signal.
However, Aozasa teaches an amplification fiber that divides an amplification fiber into two sections (Fig. 3, amplification fiber 10, first amplification fiber 10-1, second amplification fiber 10-2, Paragraph [0041]-[0043]). The first section of the amplification fiber is doped with concentric cores that amplify both the C-band and L-band frequencies (Fig. 2A, first amplification fiber 10-1, cores 11b-1 – 11b-b, Paragraph [0035]-[0036]). The second section of the amplification fiber is doped with concentric cores that amplify just L-band frequencies (Fig. 2B, second amplification fiber 10-2, cores 11b-1 – 11b-b, Paragraph [0035]-[0036]).
It would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have modified Seo’s optical fiber amplifier by adding a second section with a different arrangement of doped regions which amplifies only the light in the L-band, which is disclosed by Aozasa. One of ordinary skill in the art would have been motivated to make this modification in order to improve amplification efficiency, as suggested by Aozasa (Paragraph [0043]).
Regarding claim 4, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare-earth-doped optical fiber has a doping concentration of the rare-earth ions in at least one of the doped regions different from a doping concentration of the rare-earth ions in other of the doped regions (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0036]).
Regarding claim 5, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare-earth-doped optical fiber has a population inversion state formed for each of the doped regions (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], Paragraph [0037]: pump beam excites erbium ions; See also: [0052]), and the population inversion state used for each of the wavelength bands is different (Seo, Paragraph [0037], [0052]: erbium ions used to amplify C-band signal while remaining pump beam not used to excite erbium ions used to amplify S-band; Aozasa, Fig. 2B, second amplification fiber 10-2, cores 11b-1 – 11b-b, Paragraph [0035]-[0036]).
Regarding claim 6, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare- earth-doped optical fiber, within a cross-section of an optical fiber, has a central core in the propagation region and a core region concentrically arranged with respect to the central core (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0038]), and in at least one of the sections, the core region is the doped region (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033]).
Regarding claim 7, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare- earth-doped optical fiber has a central core in the propagation region within a cross- section of an optical fiber (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033]), and in at least one of the sections, the doped region is concentrically arranged with respect to the central core (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0038]).
Regarding claim 8, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare-earth-doped optical fiber, within a cross-section of an optical fiber, has a central core in the propagation region and a core region concentrically arranged with respect to the central core, and the doped region has the central core and the core region (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0038]).
Regarding claim 9, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 1, wherein the rare-earth-doped optical fiber has a central core that is the propagation region, within a cross-section of the optical fiber, and the doped region is arranged at a position of the central core and arranged concentrically with respect to the central core (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0038]).
Regarding claim 11, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to any one of claim 1, wherein the rare-earth-doped optical fiber has a plurality of sets of the propagation region and the doped region within a cross-section of the optical fiber (Seo, Fig. 1, optical fiber 1, core 10, cladding 20, Paragraph [0033], [0038]; Aozasa, Fig. 2B, second amplification fiber 10-2, cores 11b-1 – 11b-b, Paragraph [0035]-[0036]), and the sets are non-correlated with each other in amplification of the wavelength band (Seo, Paragraph [0037]; Aozasa, Paragraph [0036]).
Claims 10 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Seo in view of Aozasa in further view of Nishihara et al., US 20080013904 A1 (“Nishihara”).
Regarding claim 10, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 8.
Seo, as modified in view of Aozasa, does not teach: wherein the doped region located at the position of the central core and the doped region arranged concentrically with respect to the central core have different doping concentrations of the rare-earth ions.
However, Nishihara teaches an erbium doped fiber with a first and second core portion that are doped with different concentration of erbium ions (Figs. 6-7, Er ion concentrations Nt1 in first core portion 1, Er ion concentrations Nt2 in second core portion 2, Paragraph [0095], [0129]).
It would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have modified Seo and Aozasa’s optical fiber by using different rare earth doping concentrations between to core and cladding, which is disclosed by Nishihara. One of ordinary skill in the art would have been motivated to make this modification in order to “suppress an occurrence of the FWM by reducing the length of the fiber as an interaction length of action of the FWM while maintaining an amplification gain, thereby improving an amplification performance of the fiber as a whole”, as suggested by Nishihara (Paragraph [0030]).
Regarding claim 14, Seo, as modified in view of Aozasa, discloses the optical fiber amplifier according to claim 9.
Seo, as modified in view of Aozasa, does not teach: wherein the doped region located at the position of the central core and the doped region arranged concentrically with respect to the central core have different doping concentrations of the rare-earth ions.
However, Nishihara teaches an erbium doped fiber with a first and second core portion that are doped with different concentration of erbium ions (Figs. 6-7, Er ion concentrations Nt1 in first core portion 1, Er ion concentrations Nt2 in second core portion 2, Paragraph [0095], [0129]).
It would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have modified Seo and Aozasa’s optical fiber by using different rare earth doping concentrations between to core and outer core, which is disclosed by Nishihara. One of ordinary skill in the art would have been motivated to make this modification in order to “suppress an occurrence of the FWM by reducing the length of the fiber as an interaction length of action of the FWM while maintaining an amplification gain, thereby improving an amplification performance of the fiber as a whole”, as suggested by Nishihara (Paragraph [0030]).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Leplingard et al., US 6687046 B2 in view of Aozasa.
Regarding claim 17, Leplingard discloses An optical fiber amplifier that amplifies a plurality of wavelength bands, the optical fiber amplifier comprises
a rare-earth-doped optical fiber having a central core surrounded by a cladding portion (Fig. 1, core 13, inner cladding layer 14, outer cladding 15, Col. 2 lines 48-65) and divided along a longitudinal axis of the optical fiber into at least a front stage and a rear stage (Fig. 3, first amplifying stage A1, second amplifying stage A2, Col. 3 line 61 – Col. 4 line 6), where the front stage is configured to amplify signals in C band and has a first doped region substantially coinciding with the central core (Fig. 1, core 13, Col. 2 line 66 – Col. 3 line 18; Fig. 3, first amplifying stage A1, Col. 3 lines 65-66; Col. 3 lines 31-38), and the rear stage is
Leplingard does not teach: the rear stage is
However, Aozasa teaches an amplification fiber that divides an amplification fiber into two sections (Fig. 3, amplification fiber 10, first amplification fiber 10-1, second amplification fiber 10-2, Paragraph [0041]-[0043]). The second section of the amplification fiber is doped with concentric cores that amplify just L-band frequencies (Fig. 2B, second amplification fiber 10-2, cores 11b-1 – 11b-b, Paragraph [0035]-[0036]).
It would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have modified Leplingard’s second stage amplifier by amplifying only the light in the L-band, which is disclosed by Aozasa. One of ordinary skill in the art would have been motivated to make this modification in order to improve amplification efficiency, as suggested by Aozasa (Paragraph [0043]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Minelly et al., US 6459526 B1 discloses a two stage L band amplifier with a doped concentric ring.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL N NGUYEN whose telephone number is (571)270-5405. The examiner can normally be reached Monday - Friday 8 am - 5:30 pm ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Yuqing Xiao can be reached at (571) 270-3603. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/RACHEL NGUYEN/Examiner, Art Unit 3645
/YUQING XIAO/Supervisory Patent Examiner, Art Unit 3645
