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 .
DETAILED ACTION
Response to Amendment
Applicant’s Amendment filed April 27, 2026 has been fully considered and entered. The arguments presented are persuasive and as such, this action will be non-final.
Claim Rejections - 35 USC § 103
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 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.
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 of this title, 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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claims 1, 2, 5 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Sano et al. (“Crosstalk-Managed High Capacity Long Haul Multicore Fiber…” from Applicant’s July 18, 2023 Information Disclosure Statement) in view of Bickham et al (US 2021/0294029 A1).
Regarding claim 1, Sano discloses a system for bidirectionally linking optical transceivers (Fig. 3c; abstract), comprising: a first optical transceiver including a first transmitter optical port and a first receiver optical port (“Tx”, “Rx” on one side); a second optical transceiver including a second transmitter optical port and a second receiver optical port (“Tx”, “Rx” on opposite side); and a multicore optical fiber (Fig. 4) including a common cladding, a first core disposed in the common cladding, and a second core disposed in the common cladding, wherein, the first transmitter optical port is operatively coupled to the second receiver optical port by the first core of the multicore optical fiber, and the first receiver optical port is operatively coupled to the second transmitter optical port by the second core of the multicore optical fiber (see “II. Crosstalk Managed Transmission Using Propagation Direction Interleaving”).
Still regarding claim 1, Sano teaches the claimed invention except for specifically stating the mode field diameter, cable cutoff wavelength and crosstalk. Bickham discloses a multicore optical fiber (Figs. 8A-9), wherein each of the first core and the second core of the multicore optical fiber is configured to have a mode field diameter greater than 8.2 µm at 1310 nm (paragraph 0082), a cable cutoff wavelength of less than 1260 nm (paragraph 0082), and an inter-core separation distance sufficient to produce an inter core crosstalk of less than -30 dB/km in a 1550 nm wavelength window (paragraph 0159). Since both inventions relate to optical fibers, one of ordinary skill in the art at the time of the invention would have found it obvious to use the cores disclosed by Bickham in the system of Sano for the purpose of reducing crosstalk which leads to reduced transmission loss. Further, Bickham discloses the relationship between crosstalk and core spacing in Fig. 10 and as such, it would have been obvious to one having ordinary skill to arrive at an inter core counter-propagating crosstalk at both 1310 nm wavelength window and a 1550 wavelength window in order to ensure reduced crosstalk in a wide wavelength range, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 2, Sano discloses the first core and the second core of the multicore optical fiber are arranged in a 1x2 configuration in Fig. 4.
Regarding claim 5, the proposed combination of Sano and Bickham teaches the claimed invention except for specifically stating the inter-core distance. However, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed inter-core distance, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 9, Sano discloses the multicore optical fiber further includes a third core and a fourth core each disposed in the common cladding, and further comprising: a third transceiver including a third transmitter optical port and a third receiver optical port; and a fourth transceiver including a fourth transmitter optical port and a fourth receiver optical port, wherein, the third transmitter optical port is operatively coupled to the fourth receiver optical port by the third core of the multicore optical fiber, and the third receiver optical port is operatively coupled to the fourth transmitter optical port by the fourth core of the multicore optical fiber in Figs. 3c and 4.
Claims 3, 4, 6, 8, 10-12 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over Sano et al. (“Crosstalk-Managed High Capacity Long Haul Multicore Fiber…” from Applicant’s July 18, 2023 Information Disclosure Statement) in view of Bickham et al (US 2021/0294029 A1), further in view of Hayashi (US 2013/0243381 A1).
Regarding claims 3, 4 and 12, the proposed combination of Sano and Bickham teaches the claimed invention except for specifically stating each core having a step index core and a trench assisted core design. Hayashi discloses a multicore optical fiber (100 in Fig. 1), wherein each of the first core and the second core of the multicore optical fiber has a core relative refractive index of less than 0.4% (Fig. 2; paragraph 0203 discloses characteristics of Example (i) with Δ1=0.26%), a core radius larger than 4 µm (Example (i) has 2a = 12.8 µm, a = 6.4 µm), a core alpha of greater than 5 (Fig. 2 and paragraph 0181 disclose step index core, which is known to require a core alpha greater than 5), and the multicore optical fiber further includes: a first inner cladding and a second inner cladding (120) that respectively encircle the first core and the second core, and that each have a relative refractive index of 0% (paragraph 0203 discloses Example (i) with Δ2=0%) and a radius between 8 µm and 12 µm (see Fig. 1 showing Ra = a/b; since Ra = 0.6 and a = 6.4 µm, b = 10.67 µm); and a first trench region and a second trench region (130) that respectively encircle the first inner cladding and the second inner cladding, and that each have a relative refractive index of less than -0.2% (paragraph 0203 discloses Example (i) with Δ3=-0.55%) and a radius between 12 µm and 20 µm (see Fig. 1 showing Rb = b/c; since Ra = 0.819 and b = 10.67 µm, c = 13.03 µm); wherein the common cladding (140) surrounds the first trench region and the second trench region. Since all of the inventions relate to optical fibers, one of ordinary skill in the art at the time of the invention would have found it obvious to use the multicore fiber disclosed by Hayashi in the system of the proposed combination of Sano and Bickham for the purpose of ensuring sufficient transmission capacity in each core with a reduced transmission loss.
Regarding claims 6 and 29, the proposed combination of Sano, Bickham and Hayashi teaches the claimed invention except for specifically stating a protective coating. However, Hayashi discloses a multicore fiber comprising a coating covering the cladding (paragraph 0177). As such, one of ordinary skill in the art at the time of the invention would have found it obvious to use a coating surrounding the common cladding for the purpose of providing protection to the optical fiber. Further, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed diameters in order to reduce the size of the fiber, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 8, the proposed combination of Sano, Bickham and Hayashi teaches the claimed invention except for specifically stating the crosstalk. However, Bickham discloses the relationship between crosstalk and core spacing in Fig. 10 and paragraph 0160. As such, it would have been obvious to one having ordinary skill to arrive at the claimed inter core counter-propagating crosstalk in order to ensure reduced crosstalk in a wide wavelength range, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 10, Hayashi further discloses each of the first core and the second core of the multicore optical fiber has a core relative refractive index of less than 0.45% (Fig. 2; paragraph 0203 discloses characteristics of Example (i) with Δ1=0.26%) and a core alpha of greater than 5 (Fig. 2 and paragraph 0181 disclose step index core, which is known to require a core alpha greater than 5). The proposed combination of Sano, Bickham and Hayashi teaches the claimed invention except for specifically stating a core radius less than 5 µm. However, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed core diameter in order to reduce the size of the fiber, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Regarding claim 11, Hayashi further discloses a core alpha of greater than 5 (Fig. 2 and paragraph 0181 show a step index core, which is known to require a core alpha greater than 5). The proposed combination of Sano, Bickham and Hayashi teaches the claimed invention except for specifically stating a core alpha less than 12. However, it would have been obvious to one having ordinary skill in the art at the time of the invention to arrive at the claimed core alpha in order to reduce crosstalk between fibers, and since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233.
Response to Arguments
Applicant's arguments, see pages 9-14, with respect to claims have been considered but are moot in view of the new grounds of rejection.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRIS H CHU whose telephone number is (571)272-8655. The examiner can normally be reached on Mon-Fri 9AM-5PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Uyen-Chau Le can be reached on 571-272-239797. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Any inquiry of a general or clerical nature should be directed to the Technology Center 2800 receptionist at telephone number (571) 272-1562.
Chris H. Chu
/CHRIS H CHU/Primary Examiner, Art Unit 2874 July 16, 2026
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