DETAILED ACTION
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 .
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.
Response to Arguments
Applicant’s amendment to claim 1 filed 04/13/2026 has overcome the rejections under 35 U.S.C. 112. Those rejections have been withdrawn.
Applicant has cancelled claim 15. Accordingly, the rejection under 35 U.S.C. 112d has been withdrawn.
Applicant's arguments filed 04/13/2026 with respect to the rejections under 35 U.S.C. 103 have been fully considered but they are not persuasive.
On pages 8 and 9 of the response, applicant contends that Fujita does not disclose “the angled end…prevents backward propagating light in the first multi-clad fiber from coupling into the light source”. However, the Office relies on Kashiwagi does not disclose "the filter prevents at least a portion of backward-propagating optical radiation at a second wavelength from coupling into a first light source." Kashiwagi at [0113] recites "The filter 119 is constituted by an optical filter (e.g., a SWPF (Short Wavelength Pass Filter) or BPF (Band Pass Filter) that has a pass band in a visible light range and a cut-off band in an infrared light range) that transmits visible light outputted by the visible light LD 11 and attenuates the return light propagated in a reverse direction in the core from the wavelength selective coupling-splitting element 112 while irradiating invisible laser light." Return light in the infrared light range is understood to be "backward-propagating optical radiation at a second wavelength". As described in [0114] "The wavelength selective coupling-splitting element 112 also separates the return light propagating through the optical fiber 31 in the reverse direction in response to the wavelength, emits the visible light on the filter 119 side, and emits the non-visible light on the optical fiber 30 side." Accordingly, a person of ordinary skill in the art understands Kashiwagi to disclose "the filter prevents at least a portion of backward-propagating optical radiation at a second wavelength from coupling into a first light source."
Furthermore, Fujita discloses that angling an end of the fiber allows for light propagating in an outgoing direction (e.g. away from the light source) and an incoming direction opposite the outgoing direction (e.g. backward-propagating optical radiation) to be easily separated. The separated light is directed towards a receiving unit and as such cannot enter the laser diode. Accordingly, a person of ordinary skill in the art understands Fujita to teach the angled end of the fiber allows any emitted radiation in the backwards propagating direction to be directed away from the laser light source.
On pg. 9, applicant also states “Fujita et al. describes a system that differs so significantly form the claimed invention to cast doubt as to its applicability to the claims as now drafted”. The Office disagrees. To rely on a reference under 35 U.S.C. 103, the reference must be analogous art to the claimed invention. A reference is analogous art to the claimed invention if: (1) the reference is from the same field of endeavor as the claimed invention (even if it addresses a different problem); or (2) the reference is reasonably pertinent to the problem faced by the inventor (even if it is not in the same field of endeavor as the claimed invention). MPEP 2141.01(a). Here, Fujita is both in the same field of endeavor as the claimed invention and is reasonably pertinent to the problem faced by the inventor. Specifically, both the claimed invention and Fujita are in the laser assembly field. Additionally, both the claimed invention and Fujita are concerned with the coupling of light into and out of a fiber. Since Fujita is analogous art, it may be properly used in a rejection under 35 U.S.C. 103.
The rejections under 35 U.S.C. 103 have been updated for applicant’s amendments but are otherwise maintained.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 2, and 4-7 are rejected under 35 U.S.C. 103 as being unpatentable over Kashiwagi et al. (US20130299474A1), hereafter Kashiwagi, in view of Hao et al. (CN105375249), hereafter Hao, in further view of Fujita et al. (US20030169979A1), hereafter Fujita, in further view of Sung et al. (KR20170022807), hereafter Sung.
Regarding claim 1, Kashiwagi discloses a laser assembly (Title) comprising: a first fiber (Fig. 9 line connecting element 11 to element 13) optically coupled to a first light source (Fig. 9 element 11) configured to emit a first optical radiation at a first wavelength in the visible spectrum (Fig. 9 element 11; [0112]; [0113]), wherein the first fiber transmits the first optical radiation toward a workpiece (Fig. 9 line connecting element 11 to element 13; [0126]); a second fiber (Fig. 9 element line connecting element 19 to element 13) optically coupled to a second light source (Fig. 9 element 19) configured to emit a second optical radiation as laser light at a second wavelength (Fig. 9 element 19; [0064]), wherein the second fiber transmits the second optical radiation toward the workpiece (Fig. 9 line connecting element 19 to element 13; [0126]); a protective element disposed between the first light source and the first fiber (Fig. 9 element 119), wherein the protective elements prevents at least a portion of backward-propagating optical radiation at the second wavelength from coupling into the first light source ([0113]); a combiner connected to the first fiber and the second fiber (Fig. 9 element 13); and a third fiber (Fig. 9 element 15) connected to the combiner (Fig. 9 element 13), wherein the combiner combines the first optical radiation from the first fiber and the second optical radiation from the second fiber into the third fiber such that the first optical radiation is coupled into a core of the third fiber (Abstract), the second optical radiation is coupled into a cladding of the third fiber ([0121]), thereby permitting the third fiber to guide the first optical radiation and the second optical radiation to the workpiece ([0072]). Kashiwagi does not explicitly disclose the first fiber is a multi-clad fiber or the protective element is applied to an angled output end of the first multi-clad fiber and prevents at least a portion of backward-propagating optical radiation from exiting the output end. However, Hao discloses using multi-clad fiber as a fiber pigtail ([0076]). An advantage is to use a known component. Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Kashiwagi with the fiber pigtail is the multi-clad fiber as disclosed by Hao in order to use a known component and since the Court has held simply substituting one known element (a fiber pigtail) with another known element (a multi-clad fiber pigtail) to obtain predictable results (both pigtails carry light to a fiber laser) requires only ordinary skill in the art. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007). Kashiwagi in view of Hao do not explicitly disclose the protective element is applied to an angled output end of the first multi-clad fiber and prevents at least a portion of backward-propagating optical radiation from exiting the output end. However, Fujita discloses the output end of the fiber is angled (Fig. 5(b) element 29). An advantage is to help prevent the returning light from affecting the laser diode ([0108]). Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Hao with the output end of the fiber is angled as disclosed by Fujita in order to help prevent the returning light from affecting the laser diode. Kashiwagi in view of Hao in further view of Fujita do not explicitly disclose the protection element is applied to an end face of the first fiber and prevents at least a portion of backward-propagating optical radiation from exiting the output end. However, Sung discloses the protection element is applied to an end face of the first fiber (Fig. 6 element 122), wherein the protective element is disposed between the first light source and the first fiber ([0025]; Fig. 6) and prevents at least a portion of backward-propagating optical radiation from exiting the output end ([0025]). An advantage is to use a known component ([0049]) to protect a guide laser from damage ([0025]). Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Kashiwagi in view of Hao in further view of Fujita with the protective element is applied to an end face of the first fiber wherein the protective element is disposed between the first light source and the first fiber and prevents at least a portion of backward-propagating optical radiation from exiting the output end as disclosed by Sung in order to use a known component to protect a guide laser from damage and since the Court has held simply substituting one known element (the filter of Kashiwagi) with another known element (the end face filter of Sung) to obtain predictable results (both filters prevent unwanted light from entering and damaging the light source) requires only ordinary skill in the art. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 2, Kashiwagi further discloses the light source is a diode laser (Fig. 9 element 11; [0112]).
Regarding claim 4, Kashiwagi does not explicitly disclose the first multi-clad fiber is double-clad fiber comprising a core, a cladding, and a buffer layer, wherein the core has a higher refractive index than the cladding and the cladding has a higher index than the buffer layer. However, the Office takes Official Notice that the first multi-clad fiber is double-clad fiber comprising a core, a cladding, and a buffer layer, wherein the core has a higher refractive index than the cladding and the cladding has a higher index than the buffer layer are well known in the art. Some advantages include higher power with improved beam quality. Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Hao in further view of Fujita in further view of Sung with the first multi-clad fiber is double-clad fiber comprising a core, a cladding, and a buffer layer, wherein the core has a higher refractive index than the cladding and the cladding has a higher index than the buffer layer as is known in the art in order to provide a smaller diameter pump cladding resulting in stronger coupling of the pump light to the fiber core.
Regarding claim 5, Kashiwagi does not explicitly disclose the multi-clad fiber is a triple-clad fiber comprising a core, a first cladding, a second cladding and a buffer layer, wherein the core has a higher refractive index than the first cladding, the first cladding has a higher index than the second cladding and the second cladding a higher index than the buffer layer. However, the Office takes Official Notice that triple-clad fibers comprising a core, a first cladding, a second cladding and a buffer layer, wherein the core has a higher refractive index than the first cladding, the first cladding has a higher index than the second cladding and the second cladding a higher index than the buffer layer are well known in the art. Some advantages known in the art include a smaller diameter pump cladding resulting in stronger coupling of the pump light to the fiber core. Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Hao in further view of Fujita in further view of Sung with the multi-clad fiber is a triple-clad fiber comprising a core, a first cladding, a second cladding and a buffer layer, wherein the core has a higher refractive index than the first cladding, the first cladding has a higher index than the second cladding and the second cladding a higher index than the buffer layer as is known in the art in order to provide a smaller diameter pump cladding resulting in stronger coupling of the pump light to the fiber core.
Regarding claim 6, Kashiwagi does not explicitly disclose the protective element is a reflector or an absorber or a combination thereof. However, Sung discloses the protective element is a reflector or an absorber or a combination thereof (Abstract). An advantage is to use a known component ([0049]) to protect a guide laser from damage ([0025]). Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify Kashiwagi with the protective element is a reflector or an absorber or a combination thereof as disclosed by Sung in order to use a known component to protect a guide laser from damage and since the Court has held simply substituting one known element (the filter of Kashiwagi) with another known element (the reflective filter of Sung) to obtain predictable results (both filters prevent unwanted light from entering and damaging the light source) requires only ordinary skill in the art. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 7, Sung further discloses the protective element is a dichroic filter configured to transmit optical radiation at the first wavelength and to reflect optical radiation at the second wavelength ([0014]).
Claims 8, 9, and 17-21 are rejected under 35 U.S.C. 103 as being unpatentable over Kashiwagi in view of Hao in further view of Fujita in further view of Sung, as applied to claim 1 above, in further view of Yamaguchi et al. (US20020039227A1), hereafter Yamaguchi.
Regarding claim 8, Hao further disclose the fiber is a multi-clad fiber ([0076]). Sung further discloses the protective element is a dichroic filter configured to reflect optical radiation at the second wavelength ([0025]; [0027]). Kashiwagi in view of Hao in further view of Fujita in further view of Sung do not explicitly disclose the protective element is a dichroic filter configured to reflect optical radiation at the second wavelength in such a way as to couple a portion of the backward-propagating optical radiation into one or more cladding layers of the fiber. However, Yamaguchi discloses a dichroic filter configured to reflect optical radiation at the second wavelength in such a way as to couple a portion of the backward-propagating optical radiation into one or more cladding layers of the fiber (Fig. 2B element 12A; [0043]). An advantage is to help reduce the amount of light returned to the resonator ([0043]). Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Hao in further view of Fujita in further view of Sung with the protective element is a dichroic filter configured to reflect optical radiation at the second wavelength in such a way as to couple a portion of the backward-propagating optical radiation into one or more cladding layers of the fiber as disclosed by Yamaguchi in order to help reduce the amount of light returned to the resonator.
Regarding claim 9, Sung further discloses the dichroic filter is applied to an output end of the fiber (Fig. 6 element 122)
Regarding claim 17, Kashiwagi further discloses a fiber pigtail configured to be optically coupled (Fig. 9 Fiber connecting elements 11 to 112) to an input fiber (Fig. 9 element 32) of a fiber laser (Fig. 9 elements 14-16). Kashiwagi in view of Yamaguchi do not explicitly disclose the fiber pigtail is the multi-clad fiber. However, Hao discloses using multi-clad fiber as a fiber pigtail ([0076]). An advantage is to use a known component. Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Yamaguchi with the fiber pigtail is the multi-clad fiber as disclosed by Hao in order to use a known component and since the Court has held simply substituting one known element (a fiber pigtail) with another known element (a multi-clad fiber pigtail) to obtain predictable results (both pigtails carry light to a fiber laser) requires only ordinary skill in the art. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 18, Kashiwagi further discloses the pigtail is further configured to couple the optical radiation at the first wavelength from the light source to the input fiber (Fig. 9 fibers connecting elements 11 and 32), wherein the first wavelength is in the visible spectrum ([0112]) and the fiber laser is configured to propagate the optical radiation through an output fiber to a workpiece (Abstract).
Regarding claim 19, Kashiwagi further discloses the fiber laser is a diode pumped fiber laser (Fig. 9 element 19).
Regarding claim 20, Kashiwagi in view of Yamaguchi in further view of Hao do not explicitly disclose the fiber laser is a counter-pumped fiber laser. However, the Office takes Official Notice that counter-pumped fiber lasers are well known in the art. An advantage, as is known in the art, is lower ASE losses in counter-pumped fiber lasers. Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to further modify Kashiwagi in view of Hao in further view of Fujita in further view of Sung in further view of Yamaguchi with the fiber laser is a counter-pumped fiber laser as is known in the art in order to provide lower ASE losses and since the Court has held that choosing from a finite number of identified (counter-pumping, co-pumping, or bidirectional pumping), predictable (all three function to pump a laser device with various known considerations) solutions, with a reasonable expectation of success (all three have created viable fiber laser devices) requires only ordinary skill in the art. KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007).
Regarding claim 21, Kashiwagi does not explicitly disclose the protective element is configured to reflect optical radiation at the second wavelength in such a way as to direct the optical radiation away from the core. However, Yamaguchi discloses the protective element is configured to reflect optical radiation at the second wavelength in such a way as to direct the optical radiation away from the core(Fig. 2B element 12A; [0043]). An advantage is to help reduce the amount of light returned to the resonator ([0043]). Accordingly, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention further modify Kashiwagi in view of Hao in further view of Fujita in further view of Sung with the protective element is configured to reflect optical radiation at the second wavelength in such a way as to direct the optical radiation away from the core as disclosed by Yamaguchi in order to help reduce the amount of light returned to the resonator.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. See attached Notice of References Cited. US20130020474A1 discloses a bidirectional pumping configuration. US20100202481 discloses known double and triple cladding fibers.
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 JOSHUA KING whose telephone number is (571)270-1441. The examiner can normally be reached Monday to Friday 10am-5pm MT.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Min Sun Harvey can be reached on (571) 272-1835. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Joshua King/Primary Examiner, Art Unit 2828 06/22/2026
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