DETAILED ACTION
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 .
Claim Interpretation
In claim 1, the Examiner interprets a glass preform and optical fibre as the material worked upon in the apparatus. Applicant recites a claim limitation directed towards the glass preform diameter, the Examiner interprets, this limitation as representing a size limitation of the apparatus. The Examiner will broadly interpret the limitation “wherein the sealing felt is retrofitted on the optical fibre without additional adjustments” in claim 1.
In claim 8, the Examiner interprets a glass preform and optical fiber as the material worked upon in the apparatus.
In claim 8, the Examiner interprets lines 1-5 after the term “a sealing felt” up to the term “comprising” as the preamble of the claim. Therefore, the optical fibre draw furnace has not been positively recited and is not required in claim 8. Further, the positioning of the sealing felt with the pre-defined distance above the optical fibre draw furnace is in the preamble of the claim, and the positioning is interpreted as intended use and does not further limit the claim, since the optical fibre draw furnace is recited in the preamble of the claim and not positively recited in the claim. The Examiner interprets lines 6-13 as the body of the claim.
Additionally, the wherein statement in lines 11-13 in the body of the claim recites limitations based on the intended use of the apparatus, and is therefore, interpreted as such.
In claim 11, Applicant has recited a property of the material worked upon by the apparatus (i.e. the drawn optical fiber), and is therefore, interpreted as manner of operating the device/intended use of the apparatus.
Claim Objections
The amendment to the claims filed Jun. 11, 2026, is sufficient for the Examiner to withdraw the objection to claim 1.
Claim Rejections - 35 USC § 112
Applicant’s remarks filed Jun. 11, 2026, are sufficient for the Examiner to withdraw the rejection of claims 1, 4, and 5 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph. As stated in the Claim interpretation section above, the Examiner will broadly interpret the limitation “wherein the sealing felt is retrofitted on the optical fibre without additional adjustments”
Claim Rejections - 35 USC § 102/Claim Rejections - 35 USC § 103
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
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 application indicating obviousness or nonobviousness.
Claim(s) 1 and 4-5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cheng et al. (CN106746592A – hereinafter Cheng) in view of Ponader (US 2020/0369553), Fujimaki et al. (JP06279045A – hereinafter Fujimaki), and Argaw et al. (US 2019/0359517 – hereinafter Argaw).
Regarding claim 1, Cheng (Figs. 1-3, [0032], and [0042]) discloses a sealing felt (“graphite felt baffle ring 2” and “graphite felt 3”) positioned on top of a support 61 of the optical fiber draw furnace (“fiber drawing furnace 6”). Cheng illustrates the sealing felt (i.e. graphite felt baffle ring and graphite felt) positioned at a pre-defined distance above the optical fiber draw furnace. Cheng (Figs. 1-3, [0029]-[0030], and [0044]) discloses the sealing felt as having an opening of the enclosure (“sealing fitting hole 31”) (corresponding to a first opening) utilized to hold a glass preform as the glass preform is inserted in the optical fiber draw furnace and discloses a second opening of the enclosure (“inert gas introduction hole 22”), wherein the second opening facilitates input of a gas or gases inside the optical fiber draw furnace. Alternatively, if it is interpreted the second opening (i.e. inert gas introduction hole 22) does not sufficiently provide for input of a gas or gases inside the optical furnace, it would be obvious to a person having ordinary skill in the art, based on the structure of the base 1, and the drawing furnace support 61, gases introduced into the second introduction hole diffused into the graphite felt is introduced into the furnace.
Regarding wherein the sealing felt is retrofitted on the optical fiber draw furnace without additional adjustments, Cheng (Figs. 1-3, [0013], and [0029]) illustrates a base 1 having a mating cavity for the sealing felt (“graphite felt baffle ring 2” and “graphite felt 3”) and states the base is a disc-shaped base arranged on drawing furnace support 61 that is placed at the top entrance of optical fiber drawing 6. Based on the structure disclosed by Chen, it would be obvious to a person having ordinary skill in the art, the arrangement of the sealing felt at the top of the entrance of the drawing furnace within base 1 arranged on drawing furnace support 61 with a disc-shaped base having a mating cavity provides for the sealing felt is retrofitted on the optical fiber draw furnace with additional adjustments to the drawing furnace.
Cheng fails to disclose details of the optical fiber draw furnace, such as the claimed hollow cylindrical structure or one or more heating elements. However, Ponader (Fig. 1, [0003], and [0030]) teaches a drawing furnace is provided with a tube and a heater and heating elements in a drawing furnace. Therefore, based on the additional teachings by Ponader, it would be obvious to a person having ordinary skill in the art, the fiber drawing furnace of Cheng comprising a tube (corresponding to a hollow cylindrical structure) comprising a glass preform positioned inside the hollow cylindrical structure and one or more heating elements for melting the glass preform.
As discussed above, Chen discloses the sealing felt is positioned at a pre-defined distance on top of a drawing furnace support 61 at the top entrance of the optical fiber draw furnace. The Examiner interpreted the top of support 61 as the top of the draw furnace. Cheng is silent as to the exact positioning of the sealing felt relative to the top of the optical fiber draw furnace, and therefore, fails to disclose the pre-defined distance is in a range of 10-20 cm above the optical fiber draw furnace. However, Cheng ([0029]-[0030]) further teaches the sealing felt requires cooling (i.e. by base 1) and Fujimaki (Fig. 3 and [0011]) teaches temperature distribution characteristics of a drawing furnace including that temperature decreases as the distance from the heater increases. Therefore, based on the additional disclosure by Cheng, specifically cooling of the sealing felt, and teachings by Fujimaki, specifically temperature decreases as distance from the heater increases, it would be obvious to a person having ordinary skill in the art, the cooling of the sealing felt can be affected by the distance of sealing felt from the drawing furnace, since it would be obvious to a person having ordinary skill in the art, the temperature experienced by the sealing felt is relative to the pre-defined distance from drawing furnace, and therefore, it would be obvious to optimize.
Cheng fails to disclose the glass preform diameter is greater than 50 mm. As stated in the claim interpretation above, the Examiner interprets the glass preform as the material worked upon by the apparatus, and the size of the preform as a size limitation of the apparatus. Ponader ([0035]) teaches conventional optical fiber preforms having an outer diameter ranging from 90 to 150 mm. Therefore, based on the additional teachings by Ponader, it would be obvious to a person having ordinary skill in the art to provide for a sealing felt and optical fiber draw furnace that supports glass preforms having a diameter ranging from 90 mm to 150 mm, which overlaps Applicant’s claimed range of greater than 50 mm.
Cheng fails to disclose the optical fiber draw furnace supports high speed drawing of the glass preform at a drawing speed in a range of 2500 meters per minute to 3500 meters per minute. However, Argaw ([0038]) discloses to meet market demand for optical fiber and reduce fiber manufacturing costs, there is a need to increase fiber draw speeds. Argaw discloses drawing speeds of greater than 50 m/s including for example draw speeds ranging from 50 m/s to 80 m/s (3000 m/min to 4800 m/min). Based on the additional teachings of Argaw, it would be obvious to a person having ordinary skill in the art to provide for an optical fiber draw furnace of Cheng to support increased drawing speeds to meet market demand and reduce fiber manufacturing costs, such as greater than 50 m/s including for example draw speeds ranging from 50 m/s to 80 m/s. This modification provides for a draw furnace that can support high speed drawing of the glass preform at a drawing speed with a range that overlaps Applicant’s claimed range of 2500 meters/min to 3500 meters/min.
Regarding claim 4, as discussed in the rejection of claim 1 above, obviousness of Cheng in view of Ponader provides for a sealing felt and optical fiber draw furnace that supports glass preforms having a diameter ranging from 90 mm to 150 mm, which overlaps Applicant’s claimed range of about 100 mm to 150 mm.
Regarding claim 5, as discussed in the rejection of claim 1 above, Cheng (Figs. 1-3, [0029]-[0030], and [0044]) discloses a second opening of the enclosure (“inert gas introduction hole 22”), wherein the second opening facilitates input of a gas or gases inside the optical fiber draw furnace. Cheng ([0030]) further discloses an inert gas, such as argon. Therefore, it would be obvious to a person having ordinary skill in the art, the modified apparatus of Cheng wherein the gas comprises argon or other inert gases.
Claim(s) 8 and 10-11 is/are rejected under 35 U.S.C. 102(a)(1) as anticipated by or, in the alternative, under 35 U.S.C. 103 as obvious over Cheng et al. (CN106746592A – hereinafter Cheng).
Regarding claim 8, Cheng (Figs. 1-3, [0032], and [0042]) discloses a sealing felt (“graphite felt baffle ring 2” and “graphite felt 3”) positioned on top of a support 61 of the optical fiber draw furnace (“fiber drawing furnace 6”). Cheng illustrates the sealing felt (i.e. graphite felt baffle ring and graphite felt) is positioned at a pre-defined distance above the optical fiber draw furnace. Cheng (Figs. 1-3, [0029]-[0030], and [0044]) discloses the sealing felt as having an opening (corresponding to a first opening) of enclosure along the optical fiber preform (“sealing fitting hole 31”) utilized to hold a glass preform and a second opening of the enclosure (“inert gas introduction hole 22”), wherein the second opening facilitates input of a gas or gases inside the optical fiber draw furnace. Alternatively, if it is interpreted the second opening (i.e. inert gas introduction hole 22) does not sufficiently provide for input of a gas or gases inside the optical furnace, it would be obvious to a person having ordinary skill in the art, based on the structure of the base 1, and the drawing furnace support 61, gases introduced into the second introduction hole diffused into the graphite felt introduced into the furnace.
As stated in the claim interpretation above, the Examiner interprets the position of the sealing felt at a predefined distance in a range of 10-20 cm above the optical fiber draw furnace such that drawing breaks per 10,000 km length of drawn optical fiber has an upper control limit of about 1.47, as intended use of the sealing felt or manner of operating. Per MPEP 2144.II. the manner of operating the device does not differentiate the apparatus claim from the prior art, if the prior art teaches all the structural limitations of the claim. Accordingly, Cheng provides for the structure required for a sealing felt claimed in claim 8.
Regarding claim 10, as discussed in the rejection of claim 8 above, Cheng (Figs. 1-3, [0029]-[0030], and [0044]) discloses a second opening of the enclosure (“inert gas introduction hole 22”), wherein the second opening facilitates input of a gas or gases inside the optical fiber draw furnace. Cheng ([0030]) further discloses an inert gas, such as argon. Therefore, it would be obvious to a person having ordinary skill in the art, the modified apparatus of Cheng wherein the gas comprises argon or other inert gases.
Regarding claim 11, as stated in the claim interpretation above, Applicant has recited a property of the material worked upon by the apparatus (i.e. the drawn optical fiber), and is therefore, interpreted as manner of operating the device/intended use of the apparatus. Per MPEP 2144.II. the manner of operating the device does not differentiate the apparatus claim from the prior art, if the prior art teaches all the structural limitations of the claim. Accordingly, Cheng provides for the structure required for a sealing felt claimed in claim 11.
Response to Arguments
Applicant's arguments filed Jun. 11, 2026, have been fully considered but they are not persuasive.
Response to Arguments of Claims 1, 4, and 5
Applicant argues the combination of Cheng and Fujimaki. Applicant argues the Examiner’s obviousness of optimizing the distance of the sealing felt is a matter of routine experimentation based teaches by Cheng that the sealing felt requires cooling and teachings by Fujimaki of the general furnace temperature distribution of the draw furnace based on distance from the heater. Applicant alleges that optimization in high speed optical fiber drawing fluid dynamics and gas-entrainment profiles change exponentially compared to lower speeds and the distance is not a generic “cooling” gap, since it defines a critical, pressurized chamber volume necessary to maintain laminar flow of glass to prevent turbulent air from being sucked into the furnace. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., pressurized chamber volume) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
In response to applicant's argument that the distance is not a generic cooling gap but defines critical, pressurized chamber volume necessary to maintain laminar flow of gases, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985). As the Examiner has stated, since Cheng teaches cooling of the sealing felt and Fujimaki teaches temperature distribution of the furnace based on distance from the heater, the Examiner still maintains, based on the additional disclosure by Cheng, specifically cooling of the sealing felt, and teachings by Fujimaki, specifically temperature decreases as distance from the heater increases, it would be obvious to a person having ordinary skill in the art, the cooling of the sealing felt can be affected by the distance of sealing felt from the drawing furnace, since it would be obvious to a person having ordinary skill in the art, the temperature experienced by the sealing felt is relative to the pre-defined distance from the drawing furnace, and therefore, it would be obvious to optimize.
Applicant argues Hindsight combination of Argaw, since Argaw’s high-speed drawing mechanisms rely on an entirely different thermal and atmospheric environment. And simply running Cheng’s setup at Argaw’s speed while guessing a 10-20 cm distance based on Fujimaki’s thermal profiles would result in catastrophic turbulent air entrainment destroying the fiber’s structural integrity. In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971). This argument is not persuasive, as the Examiner merely relies on teachings by Argaw, specifically, Argaw ([0038]) discloses to meet market demand for optical fiber and reduce fiber manufacturing costs, there is a need to increase fiber draw speeds. Argaw discloses drawing speeds of greater than 50 m/s including for example draw speeds ranging from 50 m/s to 80 m/s (3000 m/min to 4800 m/min). Based on the additional teachings of Argaw, it would be obvious to a person having ordinary skill in the art to provide for an optical fiber draw furnace of Cheng to support increased drawing speeds to meet market demand and reduce fiber manufacturing costs, such as greater than 50 m/s including for example draw speeds ranging from 50 m/s to 80 m/s. This modification provides for a draw furnace that can support high speed drawing of the glass preform at a drawing speed with a range that overlaps Applicant’s claimed range of 2500 meters/min to 3500 meters/min. The Examiner relies on teachings by Argaw to modify the apparatus of Cheng for high speed drawing, since increased drawing speeds reduce fiber manufacturing costs.
Additionally, in response to Applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., thermal and atmospheric environments) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Accordingly, the Examiner maintains the rejection of claim 1. Additionally, claim 5 hinges upon the arguments against claim 1, and therefore, the Examiner also maintains the rejection of claim 5.
For claim 4, Applicant argues structural mismatch of large preforms, and states the Examiner combines Chen with Ponader for obviousness of handling 90-150 mm preforms. Applicant argues scaling a generic graphite felt baffle ring (like Cheng’s) to accommodate a massive 100-150 mm preform alters mechanics of the system. Applicant argues a preform of mass and size introduces massive thermal radiation upward toward the sealing felt, and argues placing the massive preform in a structure combined haphazardly from four separate references would cause the sealing felt to fail via degradation or gas bypass, because none of the cited references solve the combined problem of high-speed gas sealing and massive preform thermal management simultaneously. Applicant's arguments fail to comply with 37 CFR 1.111(b) because they amount to a general allegation that the claims define a patentable invention without specifically pointing out how the language of the claims patentably distinguishes them from the references. The Ponader reference is applied to teach optical fiber preforms having an outer diameter ranging from 90 to 150 mm. Therefore, based on the additional teachings by Ponader, it would be obvious to a person having ordinary skill in the art to provide for a sealing felt and optical fiber draw furnace that supports glass preforms having a diameter ranging from 90 mm to 150 mm, which overlaps Applicant’s claimed range of greater than 50 mm, as claimed in claim 1 and 100-150 mm, as claimed in claim 4. The Examiner maintains, it would be obvious to size the Cheng reference for known diameters of preforms, such as 90-150 mm, as taught by Ponader. Additionally, it is noted the Cheng reference teaches cooling of the sealing felt, so it is mere allegation that the sizing of Cheng for larger preforms would result in sealing felt degradation, as claimed. In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., gas bypass and high-speed gas sealing or what entails high-speed gas sealing) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Accordingly, the Examiner maintains the rejection of claim 4.
Response to Arguments of Claims 8, 10, and 11
Applicant traverses the interpretation by the Examiner. As stated in the claim interpretation section, the Examiner interprets lines 1-5 after the term “a sealing felt” up to the term “comprising” as the preamble of the claim. Therefore, the optical fibre draw furnace has not been positively recited and is not required in claim 8. Further, the positioning of the sealing felt with the pre-defined distance above the optical fibre draw furnace is in the preamble of the claim, and the positioning is interpreted as intended use and does not further limit the claim, since the optical fibre draw furnace is recited in the preamble of the claim and not positively recited in the body of the claim. The Examiner maintains the interpretation of lines 6-13 as the body of the claim. Accordingly, the Examiner maintains there is no patentable weight given to the positioning of a sealing felt in the apparatus of claims 8 and 10-11, as the positioning in the preamble is interpreted as intended use/manner of operating the apparatus.
Accordingly, arguments against the positioning of the sealing felt 10 to 20 cm above the furnace as adding patentable weight and arguments directed towards the manner of operating, such as an upper control limit of 1.457 drawing breaks as a result of drawing the material worked upon, is not persuasive as functional language that should be given patentable weight. Accordingly, the Examiner still maintains these limitations are not given patentable weight to the structure claimed in apparatus claims 8 and 10-11. As stated in the rejection of claims 8 and 10-11 above, Chen discloses the claimed structure of a sealing felt having the claimed first opening and second opening (see rejection of claims 8 and 10-11 above). Accordingly, the Examiner maintains the rejections of claims 8 and 10-11.
Summarized Table
Applicant summarizes in a table features and metrics, the present invention, what the primary art teaches and secondary art teaches. This summary appears to reiterate the arguments in tabular form discussed in the Response to Arguments of Claims 1, 4, and 5 and Response to Arguments of Claims 8, and 10-11. Accordingly, the Examiner maintains the rejections of claims 1, 4, 5, 8, and 10-11 as discussed in the Response sections above.
Conclusion
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to LISA HERRING whose telephone number is (571)270-1623. The examiner can normally be reached M-F: EST 8:15am-4:15pm.
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/LISA L HERRING/ Primary Examiner, Art Unit 1741
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