AMS RESEARCH CORPORATION

Patent Trials and Appeals Board

Mar 17, 2022

2021004761 (P.T.A.B. Mar. 17, 2022)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 15/558,572 09/15/2017 Honggang YU 11900-0041-00000 8808 109610 7590 03/17/2022 Bookoff McAndrews, PLLC 2020 K Street, NW Suite 400 Washington, DC 20006 EXAMINER EISEMAN, LYNSEY C ART UNIT PAPER NUMBER 3792 NOTIFICATION DATE DELIVERY MODE 03/17/2022 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): Kross@bomcip.com eofficeaction@appcoll.com usptomail@bomcip.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte HONGGANG YU, RONGWEI JASON XUAN, and JIAN JAMES ZHANG Appeal 2021-004761 Application 15/558,572 Technology Center 3700 Before BENJAMIN D. M. WOOD, BRETT C. MARTIN, and WILLIAM A. CAPP, Administrative Patent Judges. WOOD, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1-5, 11-15, 21-23, 28, and 31. Claims 6, 8-10, 20, 24-27, 28, and 30 have been canceled. Appeal Br. 19-22 (Claims App.). Claims 7 and 16-19 have been withdrawn. Final Act. 1 (Summary). We have jurisdiction under 35 U.S.C. § 6(b). 1 “Appellant” refers to the applicant as defined in 37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as Boston Scientific Scimed, Inc. Appeal Br. 2. Appeal 2021-004761 Application 15/558,572 2 We REVERSE. CLAIMED SUBJECT MATTER The claims are directed to a side-fire laser fiber having a molded reflective surface. Claim 1, reproduced below, is illustrative of the claimed subject matter: 1. A side-fire laser fiber comprising: an optical fiber having a distal end and a distal facing surface at the distal end; and a fiber cap having a proximal end and a proximal facing surface at the proximal end, the fiber cap being coupled to the distal end of the optical fiber via a non-fused connection, and the fiber cap comprising a molded reflective surface and a sealed cavity, wherein the distal facing surface at the distal end of the optical fiber is flush against the proximal facing surface at the proximal end of the fiber cap; wherein: the molded reflective surface defines a wall of the cavity; and laser energy discharged from the distal end along a central axis of the optical fiber is reflected off the molded reflective surface in a direction that is transverse to the central axis. REFERENCES The prior art relied upon by the Examiner is: Name Reference Date Brekke US 5,537,499 July 16, 1996 Griffin US 7,909,817 B2 Mar. 22, 2011 Adler US 2014/0249407 A1 Sept. 4, 2014 Appeal 2021-004761 Application 15/558,572 3 REJECTIONS Claims Rejected 35 U.S.C. § References 1-5, 11, 21, 31 103 Adler, Brekke 12-15, 22, 23, 28 103 Adler, Brekke, Griffin OPINION Claims 1-5, 11, 21, and 31-§ 103-Adler and Brekke Independent claim 1 recites a side-fire laser fiber comprising an optical fiber and a fiber cap coupled to the distal end of the optical fiber “via a non-fused connection,” the fiber cap comprising a molded reflective surface and “a sealed cavity.” Appeal Br. 18 (Claims App.). Independent claim 31 similarly recites a side-fiber laser fiber comprising an optical fiber and a cap attached to the distal end of the fiber via a “non-fused connection,” the cap having an “internal cavity” that is: (i) “sealed at the distal end of the cap with a cover member”; (ii) sealed at the proximal end by a total internal reflection surface; and (iii) and “filled with air.” Id. at 22-23. Claims 2-4, 11, and 21 depend from claim 1. Id. at 18-20. The Examiner relies on Adler to teach a side-fire laser fiber comprising an optical fiber and a fiber cap sealed to the fiber via a non-fused connection, but acknowledges that Adler does not teach the sealed cavity of claim 1 or the air-filled and sealed cavity of claim 31. Final Act. 4, 6 (citing Adler ¶¶ 12, 15, 70, 77, 124-126, Figs. 1, 11). The Examiner finds, however, that “there are many known beam directing means, one of which is using total internal reflection.” Id. at 4-5, 6 (citing Adler ¶ 5). The Examiner further finds that Brekke teaches that “by sealing/fusing cavity (324), such that air is always located within the cavity/chamber, total Appeal 2021-004761 Application 15/558,572 4 internal reflection occurs at the inclined surfaces.” Id. at 5, 6 (citing Brekke 1:45-2:18, 8:54-67, Fig. 22); see Brekke, Fig. 24. The Examiner determines that it would have been obvious to one of ordinary skill in the art: [T]o substitute one type of beam directing means (reflective coating 142) taught by Adler for another type of beam directing means (total internal reflection), specifically by sealing cavity shown in Fig. 11 [of Adler], to create an air/silica interface as taught by Brekke, as a simple substitution of one beam directing means for another to achieve substantially similar results.” Id. Appellant responds, inter alia, that Adler teaches avoiding total internal reflection (“TIR”), because “in many embodiments an air gap must be provided in order to use TIR for beam redirection, which ‘requires a tight seal to be maintained between the fiber and the other element to maintain the air gap.’” Appeal Br. 15 (quoting Adler ¶ 7). Appellant points to Adler’s teaching that “[t]his can be problematic when the device is immersed in water, blood, or stomach acid, or when the device is rotated or translated at high speed in order to form an image.” Id. (quoting Adler ¶ 7). Thus, according to Appellant, “[t]o proceed with the proposed combination even based on Adler’s disclosure could only be based on hindsight and would also be contrary to the teachings of Adler.” Id. In the Answer the Examiner counters that “Adler’s discussion of TIR merely mentions potential problems that CAN occur with TIR, specifically sealed cavities that provide TIR, when used in certain environments/ applications.” Ans. 4. The Examiner further contends that Adler’s own invention explicitly contemplates an embodiment with a sealed cavity filled with air.” Id. (citing Adler ¶ 103). According to the Examiner: Appeal 2021-004761 Application 15/558,572 5 While a sealed chamber filled with air (that provides TIR) may have some drawbacks in certain situations and may not be Adler’s preferred choice for a beam direction mechanism, it cannot be considered hindsight or teaching away to include such a beam direction mechanism in Adler, as Adler themselves include an embodiment with a sealed chamber filled with air. Id. at 4-5. Appellant replies that “Adler discloses problems associated with total internal reflectance (TIR), including maintaining an air gap between the fiber and other elements.” Reply Br. 2. Appellant further contends that while the Examiner is correct that Adler teaches an embodiment that includes an air gap, “this trapped air does not provide TIR.” Reply Br. 2-3. A prior art reference must be considered in its entirety, including portions that would lead or teach away from the claimed invention. W.L. Gore & Assoc., Inc. v. Garlock, Inc., 721 F.2d 1540, 1550 (Fed. Cir. 1983). “A reference may be said to teach away when a person of ordinary skill, upon reading the reference . . . would be led in a direction divergent from the path that was taken by the applicant.” In re Haruna, 249 F.3d 1327, 1335 (Fed. Cir. 2001) (quoting Tec Air, Inc. v. Denso Mfg. Mich. Inc., 192 F.3d 1353, 1360 (Fed. Cir. 1999)). A reference’s “mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed.” In re Fulton, 391 F.3d 1195, 1201 (Fed. Cir. 2004). A medical side-fire laser fiber generally comprises an optical fiber and a fiber cap over a distal end of the optical fiber. See Spec. ¶ 3 (describing a prior-art embodiment). A laser source generates laser energy that is transmitted through the optical fiber, reflected laterally off of a beveled Appeal 2021-004761 Application 15/558,572 6 surface at the distal end of the optical fiber, and discharged from a side port in the fiber cap to targeted tissue. Id. ¶¶ 3, 6, Fig. 13. As the Examiner correctly notes, Adler teaches several means by which light may reflected, or “redirect[ed],” relative to the optical-fiber axis. Final Act. 4-5, 6 (citing Adler ¶ 5). Relevant to this case, a side-fire laser fiber may: (1) use a reflective coating on the distal reflecting surface; or (2) use total internal reflection (TIR) of light from the angled end face of the fiber. Adler ¶ 5; see also Brekke 1:17-21, 24-26. Adler teaches that “to use TIR for beam redirection,” in “many embodiments an air gap must be provided.” Id. ¶ 7; see Spec. ¶ 6 (“An air cavity 322 surrounds the surface 320 to promote total internal reflection of laser energy 310 off the surface 320.”). As the Specification makes clear, the air gap is provided distal to the reflective surface. Spec. ¶ 6, Fig. 13. According to Adler, an air gap “requires a tight seal to be maintained between the fiber and the other element to maintain the air gap,” which “can be problematic when the device is immersed in water, blood, or stomach acid, or when the device is rotated, or translated at high speed in order to form an image.” Adler ¶ 7. The effect of this and other “drawbacks” is that “certain miniature optical systems are expensive, difficult to manufacture, prone to damage, and do not produce a circular output at the focal plane.” Id. Adler’s device uses a reflective coating on its distal reflective surface rather than TIR. Adler ¶¶ 11-13, 70, Figs. 1, 11. We agree with Appellant that Adler teaches away from using TIR- with-air-gap redirecting means in place of its reflective-coated-surface redirecting means. Adler teaches that maintaining the air gap required for TIR is “problematic” in certain operating conditions, and at least partially as Appeal 2021-004761 Application 15/558,572 7 a result, optical systems that use TIR are “expensive, difficult to manufacture, [and are] prone to damage.” Adler ¶ 7. Such characterizations can readily be understood as criticisms of TIR (and particularly the required air gap/sealed cavity) that would discourage its use and, more specifically, discourage using Brekke’s TIR/sealed cavity with Adler’s probe. The Examiner notes that Adler discusses potential problems that “can” occur with TIR “when used in certain environments/applications.” Ans. 4 (emphasis omitted). It is true that Adler does not categorically dismiss the use of TIR (with a sealed cavity) in all cases. But Adler deems using TIR/sealed cavity sufficiently problematic to at least contribute to devices using it being “expensive, difficult to manufacture, [and] prone to damage,” which, as stated above, constitutes criticism sufficient to be considered teaching away. The Examiner also notes that Adler teaches an embodiment with a sealed cavity filled with air. Ans. 4 (citing Adler ¶ 103). The air gap to which the Examiner refers does not appear to be related to TIR, however. It is found on an embodiment that employs a cap with “a different cavity shape because of the additional lensed surface 83.” Adler ¶ 102, Fig. 5. In this embodiment, “light radiat[es] from the fiber tip [and] expands into a gap G” that “may be filled with air to allow more rapid beam expansion.” Id. ¶ 103. The light then passes through lensed surface 83 and impinges on reflective surface 25’, where it is reflected laterally. Id. ¶¶ 102-103, Fig. 5. The gap is therefore positioned between the optical fiber tip and the reflective surface, rather than distal to the reflective surface, as would be the case for air gaps used in conjunction with TIR. See Spec. ¶ 6, Fig. 13; Brekke 1:17- 21, 24-26. Therefore, we are not persuaded that Adler’s teaching of an Appeal 2021-004761 Application 15/558,572 8 embodiment with this particular air gap is inconsistent with Adler’s criticism of an air gap used in conjunction with TIR. For the above reasons, we are not persuaded that one of ordinary skill in the art would have combined Adler and Brekke in the proposed manner, and therefore do not sustain the Examiner’s rejection of claims 1-5, 11, 21, and 31 as unpatentable over Adler and Brekke. Claims 12-15, 22, 23, and 28-§ 103-Adler, Brekke, and Griffin Claims 12-15 depend from claim 31. Appeal Br. 19-20 (Claims App.). Griffin is not relied on to cure the deficiency discussed above with respect to the combination of Adler and Brekke. Final Act. 7-9. Therefore, for the reasons discussed above, we do not sustain the Examiner’s rejection of claims 12-15 as unpatentable over Adler, Brekke, and Griffin. Similar to claim 31, independent claim 22 recites a side-fiber laser fiber comprising an optical fiber and a molded glass cap attached to the distal end of the fiber via a “non-fused connection,” the cap having an “internal cavity” that is sealed at the distal end “with a biocompatible material” and “filled with air.” Id. at 21. Claims 23 and 28 depend from claim 22. Id. at 22. As with claims 1 and 31, the Examiner relies on the combination of Adler and Brekke to teach these limitations. As discussed above, however, we are not persuaded that one of ordinary skill in the art would have combined Adler and Brekke in the proposed manner. Accordingly, we do not sustain the Examiner’s rejection of claims 22, 23, and 28 as unpatentable over Adler, Brekke, and Griffin. Appeal 2021-004761 Application 15/558,572 9 DECISION SUMMARY Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 1-5, 11, 21, 31 103 Adler, Brekke 1-5, 11, 21, 31 12-15, 22, 23, 28 103 Adler, Brekke, Griffin 12-15, 22, 23, 28 Overall Outcome 1-5, 11-15, 21-23, 28, 31 REVERSED