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 .
Specification
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Drawings
The drawings were received on Feb. 2, 2026. These drawings are accepted. Therefore, the Examiner withdraws the objection to the drawings.
Double Patenting/Terminal Disclaimer
The terminal disclaimer filed on Feb. 2, 2026 disclaiming the terminal portion of any patent granted on this application which would extend beyond the expiration date of Application No. 18/387,646 has been reviewed and is accepted. The terminal disclaimer has been recorded.
Accordingly, the provisional rejection of claims 1, 15, and 17 on the ground of nonstatutory double patenting as being unpatentable over claims 9 and 10 of copending Application No. 18/387,646 (reference application) in view of Rosenberger et al. (US 2022/0234936A1 – hereinafter Rosenberger) has been withdrawn.
Claim Interpretation
In claim 1, Applicant claims “at least one glass tube” in line 2, and references “the glass tube” in claims 1-5 and 7-18. The Examiner interprets “the glass tube” as representing only one glass tube of the at least one glass tube, in claims 1-5 and 7-18.
In claim 1, Applicant has claimed an inner capillary and in the specification states the tube forms the capillary through which gas flows (PGPUB [0031]). Accordingly, the Examiner is applying this interpretation of the term inner capillary and not the standard term for capillary, which is a tube.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
The amendment to the claims filed Feb. 2, 2026 is sufficient for the Examiner to withdraw the rejection of claims 5-7, 9-14, and 19-20 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph is withdrawn.
EXAMINER’S Comment - Withdrawal of Allowable subject Matter
Upon further review of the prior art and interpretation of the term “inner capillary” in the claims, the Examiner must withdraw allowability of amended claim 1 (previously claim 16) stated in the non-final office action dated Oct. 21, 2025. A new grounds of rejection and allowable subject matter is discussed below.
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 application indicating obviousness or nonobviousness.
Claim(s) 1-3, 6, and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Rosenberger et al. (US 2022/0357506A1 – hereinafter Pub’506) in view of Rosenberger et al. (US 2022/0234936A1 – hereinafter Rosenberger) and as evidenced by Uebel et al. (US 2025/0313504 – hereinafter Uebel).
Regarding claim 1, Pub’506 (abstract and [0039]) discloses a method of producing an anti-resonant hollow core fiber. Pub’506 discloses the method comprising manufacturing a primary preform comprising a cladding tube containing anti-resonance elements. Pub’506 (abstract, Fig. 1, [0012]-[0021], and [0108]) discloses providing a cladding tube (corresponding to a glass outer cladding) and providing and arranging a number of tubular anti-resonance element preforms including tube 4a (corresponding to at least one glass tube) to form the primary preform. Pub’506 ([0016]-[0021]) further discloses collapse of additional material sheath material and a subsequent elongation process and the elongation process as a hot-forming process. Additionally, Pub’506 ([0057]) discloses the anti-resonance element preforms having open ends (corresponding to a first open end and a second open end) and since the anti-resonance elements are tubes that provide the structure for flow within the tube, accordingly, the space in the tube (i.e. anti-resonance element) provides for the claimed inner capillary.
Based on the disclosures by Pub’506 discussed above, the step of arranging tubular anti-resonance elements in a cladding tube provides for positioning at least one glass tube (i.e. tube 4a) in a glass outer cladding to form a preform precursor, the glass tube comprising a first open end and a second open end and the collapse of additional sheath material prior to elongation provides for forming a preform from the preform precursor.
Additionally, Pub’506 (abstract) discloses a process of elongating the primary preform to form a secondary preform or hollow core optical fiber. Pub’506 ([0016]-[0021]) discloses elongation comprising a hot-forming process. Pub’506 ([0048]) discloses during elongation the primary preform is continuously supplied to a heating zone at a feed rate, softens zonally in the heating zone, and is removed from the heating zone at a removal rate. Pub’506 ([0057]) discloses sealing and bonding compound may also advantageously be used to seal open ends of the anti-resonance element preforms and/or individual structural elements of the anti-resonance element preforms when the primary preform is elongated and/or when the hollow-core optical fiber is drawn. Based on the disclosures discussed above, the method of Pub’506 provides for thermally treating a preform, such as a sheathed primary preform, comprising sealing the first open end and the second open end of the glass tube (i.e. any one of the anti-resonance element preforms) to form a closed tube and heating the glass tube. Pub’506 fails to explicitly state heating to manipulate the gas pressure within the closed glass tube. However, Pub’506 ([0057]-[0058]) discloses the sealing and bonding individual components of the primary or secondary preform allows the individual components to be subjected to different internal pressures during elongation or during drawing, and Rosenberger (Figs. 1-6, [0103]) discloses anti-resonance element preforms composed of glass tubes and an outer cladding tube (“cladding tube 2”) and ([0065]) teaches it is known in the art to seal open ends of inner tubes within a preform to affect pressurization or evacuation to provide for positionally accurate defined pressure control in a fiber drawing process. Accordingly, based on the additional teachings by Rosenberger, it would be obvious to a person having ordinary skill in the art, in the method of Pub’506 that the sealed ends of the glass tube to form a closed glass tube with gas within combined with the thermally treating (i.e. elongating) the sheathed primary preform would affect pressurization or evacuation of gas within the closed glass tube, and therefore, the elongation process (i.e. thermally treating) would include heating that will manipulate gas pressure within the closed glass tube.
Pub’506 fails to disclose the thermally treating as heating the glass tube to increase gas pressure. However, Pub’506 ([0048]) discloses during elongation (i.e. hot forming/thermally treating) the primary preform is continuously supplied to a heating zone at a feed rate, softens zonally in the heating zone, and is removed from the heating zone at a removal rate. Additionally discussed in the rejection of claim 1 above, based on the additional teachings by Rosenberger, it would be obvious to a person having ordinary skill in the art, in the method of Pub’506 that the sealed ends of the glass tube to form a closed glass tube with gas within combined with the thermally treating (i.e. elongating) would affect pressurization or evacuation of gas within the closed glass tube, and therefore, the elongation process (i.e. thermally treating) would include heating that will manipulate gas pressure within the closed glass tube, as claimed. Additionally, Pub’506 ([0114]) discloses the heating zone is kept at a temperature of 1600 degrees C during the hot-forming process (i.e. elongating process). Based on the disclosures by Pub’506, the method of Pub’506 provides for the claimed thermally treating the glass tube comprises heating the glass tube comprises gas within the glass tube with a temperature of 1600 degrees C. While Pub’506 in view of Rosenberger fails to disclose the heating of the glass tube increasing gas pressure within the glass tube, based on the elongating process that includes heating of the primary preform that includes gas within the sealed glass tube, and knowledge of the ideal gas law PV=nRT (i.e. P = nRT/V) as evidenced by Brittanica, it would be obvious to a person having ordinary skill in the art, the heating during elongated of the sealed glass tube provides for an environment during hot forming (i.e. elongating) where the volume (V) and number of moles (n) of the of the gas within the tube remains constant, and therefore, increased temperature during the elongating would result an increasing gas pressure within the glass tube as claimed.
Pub’506 fails to disclose heating the glass tube increases an outer diameter of the inner capillary and decreases a wall thickness of the glass tube. However, as discussed above, Pub’506 ([0057]-[0058]) discloses the sealing and bonding individual components of the primary or secondary preform allows the individual components to be subjected to different internal pressures during elongation or during drawing, and Uebel ([0112]) teaches a preform having a capillary with capillary cavities CAP-2 that are similar to the glass tubes (i.e. ARE preforms) of Pub’506 in Fig. 10(b). The capillary cavities are inflated with increased pressure so their outer diameter is increased, and in Fig. 10(c) illustrates the capillary cavity (corresponding to an inner capillary) having an increased diameter and discloses reduced wall thickness of the capillary (corresponding to a glass tube). Accordingly, it would be obvious to a person having ordinary skill in the art, the method of Pub’506 in view of Rosenberger the glass tube (i.e. antiresonance elements) with increased pressure during elongation/drawing would provide for applying gas pressure during heating to increase an outer diameter of the inner capillary and decreasing the glass diameter of the
Regarding claims 2-3, as discussed in the rejection of claim 1 above, Pub’506 discloses thermally treating the glass tube during elongating or drawing of the sheathed primary preform in a hot-forming process. Pub’506 ([0114]) discloses the heating zone is kept at a temperature of 1600 degrees C during the hot-forming process. Accordingly, it would be obvious to a person having ordinary skill in the art, the method of Pub’506 in view of Rosenberger that with a heating zone temperature of 1600 degrees C would provide for thermally treating the glass tube comprising heating the glass tube to a temperature of about 1600 degrees C, which is within Applicant’s claimed range of about 1100 degrees C to about 2200 degrees C, as claimed in claim 2, and within Applicant’s claimed range of about 1100 degrees C to about 1700 degrees C, as claimed in claim 3.
Regarding claim 6, as discussed in the rejection of claim 1 above, Pub’506 (Fig. 1 and [0108]) discloses tubular anti-resonant elements 4a and 4b and hot-forming (i.e. thermally treating) the primary preform. Accordingly, based on the disclosures of Pub’506, the method of Pub’506 provides for a second glass tube, such as tubular anti-resonant element 4b being a nested tube disposed radially interior of the glass tube (i.e. tube 4a) and the hot-forming of the primary preform provides for thermally treating the second glass tube.
Regarding claim 20, as discussed in the rejection of claim 1 above, Pub’506 (Fig. 1 and [0108]) discloses tubular anti-resonant elements 4a and 4b and hot-forming (i.e. thermally treating) the primary preform. Accordingly, based on the disclosures of Pub’506, the method of Pub’506 provides for a second glass tube, such as tubular anti-resonant element 4b being a nested tube disposed radially interior of the glass tube (i.e. tube 4a). Accordingly, the modified method of claim 1 provides for the at least one glass tube comprises a second glass tube. Also discussed above, Pub’506 ([0057]-[0058]) discloses the sealing and bonding individual components of the primary or secondary preform allows the individual components to be subjected to different internal pressures during elongation or during drawing. Accordingly, it would be obvious to a person having ordinary skill in the art, the tubes 4b (corresponding to a second glass tube) taught by Pub’506 as an individual structural element that may be sealed at both ends, and further the hot-forming of the primary preform with the tube 4a (i.e. glass tube) and tube 4b (i.e. second glass tube) provides for heating the second glass tube to a second temperature. Additionally, as taught previously in claim 1, based on the elongating process that includes heating of the primary preform that includes gas within the sealed second glass tube, and knowledge of the ideal gas law PV=nRT (i.e. P = nRT/V) as evidenced by Brittanica, it would be obvious to a person having ordinary skill in the art, the heating during elongated of the sealed second glass tube provides for an environment during hot forming (i.e. elongating) where the volume (V) and number of moles (n) of the of the gas within the tube remains constant, and therefore, increased temperature during the elongating would result an increasing gas pressure within the glass tube as claimed.
Claim(s) 9-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Rosenberger et al. (US 2022/0357506A1 – hereinafter Pub’506) in view of Rosenberger et al. (US 2022/0234936A1 – hereinafter Rosenberger) and as evidenced by Poletti et al. (US 2020/0278491 – hereinafter Poletti) as applied to claim 1 above, and further in view of Adigrat et al. (US 2015/0329403A1 – hereinafter Adigrat) and Han et al. (US 2011/0058780A1 – hereinafter Han).
Regarding claim 9, as discussed in the rejection of claim 1 above, Pub’506 discloses the step of arranging tubular anti-resonance elements in a cladding tube provides for positioning at least one glass tube (i.e. tube 4a) in a glass outer cladding to form a preform precursor, the glass tube comprising a first open end and a second open end and the collapse of additional sheath material prior to elongation provides for forming a preform from the preform precursor. Pub’506 ([0022]) further teaches the sheath made of glass and ([0040]) the addition of sheath material is accomplished by collapsing a collecting cylinder onto the primary preform. Pub’506 fails to disclose consolidating the preform precursor to form the preform and wherein the thermally treating the glass tube is after depositing soot on the preform precursor during the consolidation of the preform precursor. However, Adigrat ([0003]) discloses jacketing a core rod (i.e. preform) by either a rod in tube type method, which is similar to the method of Pub’506, or by depositing soot about the preform and Han ([0031]) teaches depositing an outer cladding by OVD/VAD in lieu of a jacketing tube and ([0017]-[0018]) teaches sintering processes (i.e. consolidating) the outer cladding. Accordingly, based on the additional teachings by Adigrat and Han, it would be obvious to a person having ordinary skill in the art, the sheathing of the preform precursor to form the preform could be substituted by the steps of depositing soot on the preform precursor and sintering (corresponding to consolidating) of the preform, since both the sheathing and depositing and sintering (corresponding to consolidating) provide for depositing a glass sheath around the precursor preform. Further, since the sheathing occurs prior to elongating, the modified method of Pub’506 would provide for the thermally treating (i.e. elongating) the glass tube is after depositing soot on the preform precursor during the consolidation of the preform precursor.
Regarding claim 10, as discussed in the rejection of claim 1 above, the thermal treatment is provided by elongating the preform including the glass tube. Therefore, the glass tube experiences the thermal treatment and the glass tube that experiences the thermal treatment is a glass tube of the preform.
Allowable Subject Matter
Claims 4 and 21 is/are allowed.
Claims 5, 7-8, 11-14, and 19 is/are 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.
The following is a statement of reasons for the indication of allowable subject matter is discussed below.
Regarding claim 5, as discussed above, Pub’506 teaches sheath is added prior to elongation (thermally treating). Accordingly, Pub’506 provides for thermally treating the glass tube after depositing sheath. Accordingly, the prior art fails to disclose or fairly suggest the method of claim 5.
Regarding claim 7, the prior art fails to disclose or fairly suggest wherein during the thermal treatment of the glass tube and the thermal treat of the second glass tube, the glass tube is heated to a different temperature than the second glass tube.
Regarding claim 8, the prior art fails to disclose or fairly suggest the thermally treating the glass tube comprises heating gas in a radially central portion of the glass tube to a higher temperature than gas at a radially peripheral portion of the glass tube.
Regarding claims 11-14, the prior art fails to disclose or fairly suggest the method of claim 9 further comprising redrawing the preform and drawing the preform, wherein the redrawing is before the drawing of the preform and after the thermally treating of the glass tube.
Regarding Claim 19, Pub’506 (Fig. 1 and [0108]) discloses tubular anti-resonant elements 4a and 4b and hot-forming (i.e. thermally treating) the primary preform. Accordingly, based on the disclosures of Pub’506, the method of Pub’506 provides for a second glass tube, such as tubular anti-resonant element 4b being a nested tube disposed radially interior of the glass tube (i.e. tube 4a) the prior art. However, Pub’506 fails to disclose or fairly suggest cooling the second glass tube and sealing both ends of the second glass tube to decrease a gas pressure within the second glass tube.
Regarding claims 21 and 4, the prior art fails to disclose or suggest the method of claim 21, and claim 4 depends from claim 21.
Conclusion
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/LISA L HERRING/ Primary Examiner, Art Unit 1741