DETAILED ACTION
1. This Office Action is responsive to claims filed for No. 18/519,189 on July 27, 2026. Please note Claims 1, 2 and 5-22 are pending.
Notice of Pre-AIA or AIA Status
2. The present application is being examined under the pre-AIA first to invent provisions.
Allowable Subject Matter
3. Claims 14-22 allowed.
Claims 14 and 20 recite aspects of Claim 11, which, as discussed below, contain allowable subject matter.
4. Claims 9 and 11 objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 9 recites a specific doping concentration of multiple sublayers and this level of detail, as a whole, is not taught by the prior art.
Claim 11 recites a specific formula for doping concentration and this level of detail, as a whole, is not taught by the prior art.
Claim Rejections - 35 USC § 103
5. 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.
6. 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 application indicating obviousness or nonobviousness.
7. Claims 1, 3, 4, 6, 7, 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Zhu ( US 2014/0307304 A1 ).
Zhu teaches in Claim 1:
An erbium-doped fiber ( Figure 1A, [0029] discloses a Erbium-doped fiber (EDF) ), comprising:
a fiber core ( Figure 1A, [0029] discloses DC-MC-EDF 100 ),
wherein the fiber core of the erbium-doped fiber includes a first layer ( Figure 1, [0029] discloses cores 105a-105g ) and a second layer ( Figure 1A, [0029] discloses inner cladding 110 and outer cladding 115 (read together as a second layer, consistent with Applicant’s specification and claims. Please note 115) )
the first layer includes a center of the fiber core ( Figure 1A, [0029] discloses the cores 105 are in the center of the fiber ),
the second layer is an annulus ( Figure 1A shows 110/115, notably 115, is a circular form, i.e. annulus ),
an outer ring of the annulus is an outer ring of the fiber core ( Figure 1A shows 110/115, notably 115, is an outer ring of 100 ), and
an average doping concentration of erbium ions of the first layer is higher than an average doping concentration of erbium ions of the second layer [by M percent, and M ranges from 30 to 75.6] ( Figure 7, [0059] discloses cladding concentration of Erbium (for layers 110/115) is lower than concentrations of the more highly doped core regions (for 105a-105g). To clarify, the concentration of Erbium decreases from the center going outward ); but
Zhu may not explicitly teach wherein the average doping concentration of erbium ions of the first layer is higher than the average doping concentration of erbium ions of the second layer “by M percent, and M is greater than or equal to 30.”
However, Zhu teaches in [0059] of the cladding regions may being more prone to detrimental effects and as a result, the erbium concentration is less here. As for it being greater than or equal to 30 percent, respectfully, this is a design choice/obvious to optimize issue. While doping is useful for signal amplification/transmittance, there are limits to this and one of ordinary skill in the art would realize to design the concentrations to achieve transmission while still avoiding detrimental effects. Specifically for a range from 30 to 75.6, respectfully, this range is wide enough (not specific for a reason/unexpected benefit) to fall under the same reasoning
Therefore, it would have been obvious to one of ordinary skill in the art, at the effective filed date of the invention, to implement the percentage of concentrations relative to each other, with the motivation that it is an obvious to optimize issue, ( Zhu, [0059] ).
Zhu teaches in Claim 6:
The erbium-doped fiber according to claim 1, wherein
a cross-sectional area of the first layer is within N percent of a cross-sectional area of the fiber core, and N is less than or equal to 50. ( Figure 1A, considering the core 105a-105g, either added individually or an arbitrary shape to encompass them, regardless, would result in less than or equal to 50 percent of 100 )
Zhu teaches in Claim 7:
The erbium-doped fiber according to claim 6, wherein N is between 20 and 50. ( Figure 1A, to expand on the above reasoning, upon visual inspection, the area reasonably falls within this claimed range )
As per Claim 12:
Zhu does not explicitly teach “wherein a radius of the fiber core is between 0.01 micrometers and 0.3 micrometers.”
However, Zhu teaches in Figure 1, [0029] of various diameters of the parts of the fiber 100, including d3 for the diameter/radius of the fiber core. Respectfully, given the various sizing and dimensioning shown, it is clear Zhu is concerned with the design aspects of the fiber and as such, the particular radius, etc, is a design choice issue.
Therefore, it would have been obvious to one of ordinary skill in the art, at the effective filed date of the invention, to implement the radius sizing, with the motivation that it is a design choice issue, ( Zhu, [0029] ).
Zhu teaches in Claim 13:
The erbium-doped fiber according to claim 1, wherein the erbium-doped fiber includes the fiber core and cladding from inside to outside. ( Figure 1A shows the core 105a-105g on the inside and cladding 110/115 from inside to outside )
8. Claims 2 and 10 are rejected under 35 U.S.C. 103 as being unpatentable over Zhu
( US 2014/0307304 A1 ), as applied to Claim 1, further in view of Takasaka et al.
( US 2023/0123319 A1 ).
As per Claim 2:
Zhu does not explicitly teach “wherein the erbium-doped fiber is used in an L band.”
However, optical amplification in different wavelengths (bands) is well known in the art. To emphasize, in the same field of endeavor, optical fiber cables, Takasaka teaches of optical amplifications in various bands, such as C and L bands, ( Takasaka, [0033] ).
Therefore, it would have been obvious to one of ordinary skill in the art, at the effective filed date of the invention, to implement the transmission in the L band, as taught by Takasaka, with the motivation that this is a well known band and can be used depending on the desired level of optical amplification, ( Takasaka, [0033] ).
As per Claim 10:
Zhu does not explicitly teach “wherein a doping concentration of erbium ions at the center of the fiber core is between 1500 ppm and 4000 ppm.”
However, in the same field of endeavor, optical fiber cables, Takasaka teaches in a core portions 1A, ( Takasaka, Figure 1, [0027] ), similar to Zhu. Notably, Takasaka teaches in [0028] of an erbium concentration in a range of 250 pm to 2000 ppm (included within the claimed range). Furthermore, given the core regions are normally doped with Erbium, the exact concentration is a design choice issue.
Therefore, it would have been obvious to one of ordinary skill at the effective filed date of the invention, to implement the erbium concentration range, as taught by Takasaka, with the motivation that the concentrations can vary and is a design choice issue.
9. Claim 5 rejected under 35 U.S.C. 103 as being unpatentable over Zhu
( US 2014/0307304 A1 ), as applied to Claim 1, further in view of Anderson et al.
( US 2003/0145629 A1 ).
As per Claim 5:
Zhu does not explicitly teach “wherein the average doping concentration of erbium ions of the first layer is between 2742 parts per million (ppm) and 2966 ppm, and the average doping concentration of erbium ions of the second layer is between 1560 ppm and 2280 ppm.”
However, in the same field of endeavor, optical fiber cables, Anderson teaches of an optical fiber 10 with a core 12, ( Anderson, Figure 4, [0044] ). Notably, the core 12 can be doped with a concentration of erbium in a range of 15 ppm to 3000 ppm (inclusive of the claimed range). Furthermore, given the core regions are normally doped with erbium, the exact concentration is a design choice issue. Furthermore, Zhu teaches to have the erbium concentration of the interpreted second layer to be less, consistent with the claim language for the concentration of the second layer relative to the first layer.
Therefore, it would have been obvious to one of ordinary skill at the effective filed date of the invention, to implement the erbium concentration range, as taught by Anderson, with the motivation that the concentrations can vary and is a design choice issue.
10. Claim 8 rejected under 35 U.S.C. 103 as being unpatentable over Zhu
( US 2014/0307304 A1 ), as applied to Claim 1, further in view of Ainslie et al.
( US 5,278,850 ).
Zhu teaches in Claim 8:
The erbium-doped fiber according to claim 1, wherein
[the first layer includes K sublayers, K is an integer greater than 1,]
the second layer includes P sublayers, P is an integer greater than 0 ( Zhu, Figure 1A shows 110 and 115, at least ), and
doping concentrations of erbium ions of the K sublayers and the P sublayers gradually decrease along the center of the fiber core from inside of the fiber core to outside of the fiber core ( Zhu, [0059] discloses the erbium concentration is less in 110/115 than in 105, and as such, decreases from the center to the outside of 100, as shown ); but
Zhu does not explicitly teach “the first layer includes K sublayers, K is an integer greater than 1”.
However, in the same field of endeavors, optical fiber cables, Ainslie teaches of a core region comprising inner region 14 and outer region 13, ( Ainslie, Figures 1 and 2, Columns 4-5, Lines 64-5. Please note this is interpreted as a plurality of sublayers.
Therefore, it would have been obvious to one of ordinary skill in the art, at the effective filed date of the invention, to implement the multiple sublayers, as taught by Ainslie, with the motivation that different amounts of erbium can be dosed as well as different compositions can be used to design the core, ( Ainslie, Columns 4-5, Lines 64-5 ).
Response to Arguments
11. Applicant’s arguments considered, but are respectfully not persuasive.
Please note the updated rejection, notably for Claim 1.
Zhu teaches to have a different concentration between the interpreted first and second layers, for the erbium ions, as noted in Figure 7, [0059]. Respectfully, it is well known to have the concentration of Erbium decrease from the center going outward, for a variety of reasons. The exact percentage difference between the two layers is an optimization issue/design choice issue. One of ordinary skill realizes the benefits of erbium doping in the inner cladding and realizes the diminishing concentration in the outer cladding and the exact percentage difference is not a patentable distinction as a result. Furthermore, the claimed range is wide enough such that one of ordinary skill would be able to adjust the concentrations accordingly simply through design choice/optimization.
Conclusion
12. THIS ACTION IS MADE FINAL. 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.
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/DENNIS P JOSEPH/Primary Examiner, Art Unit 2621
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