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 .
Response to Arguments
Applicant's arguments filed September 02, 2025 have been fully considered but they are not persuasive. The applicant has argued on page 5 of the arguments that “…The Office Action maps the feature "the first reflectivity profile and the second filter profile being spectrally detuned from one another" recited in independent claims 1 and 26 to Fig. 1 and col. 3, lines 15-57, of Kim. Respectfully, this mapping is no longer applicable in view of the new claim language. Indeed, Kim describes an optical fiber amplifier which is meant to be used as a gain-adjustable amplifier for an external seed signal with a narrow spectrum. More specifically, in Kim, the resonant cavity serves to establish a continuous wave (CW) oscillation of light at a specific wavelength, which in turns can saturate the gain medium and thus stabilize the gain for other signals amplified by the same gain medium (make it independent of the intensity fluctuations of these other signals). The overlapping of the two optical fiber gratings 3 and 6 shown in Fig. 1 is adjusted to control the resulting gain. This overlapping is shown and described with reference to Fig. 2 of Kim. As shown in this figure, the reflectivity profiles of the two optical fiber gratings 3 and 6 may be spectrally detuned from one another, but they are substantially overlapping with one another. It is known from plain reading of Kim that the reflectivity profiles should always have a spectral overlap to induce a continuous laser emission which can change the gain level by reducing the population inversion. It is respectfully submitted that should the reflectivity profiles of the two optical fiber gratings 3 and 6 be spectrally non-overlapping or spectrally overlapping only to the extent that adjacent tails of the two reflectivity profiles overlap with one another, then no continuous emission could be induced within Kim's cavity thereby defeating its optical amplification purpose. Kim thereby does not teach this feature of independent claims 1 and 26.”
The examiner does not agree. Fig. 2 of Kim shows adjacent tails of the first reflectivity profile (right side of reflectivity peak of curve R1 ) and the second filter profile (left side of reflectivity peak of curve R2) overlap with one another (Figs. 1 and 2, col. 3, lines 15 to col. 4, line 26). The overlap shown in Fig. 2 of Kim forms a resonant cavity and serves to establish a continuous wave (CW) oscillation of light at a specific wavelength.
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 (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.
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.
Claims 1-6, 9-11, 16-18 and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 6,137,932) in view of Reed et al. (US 5,815,518), Kuksenko (US PG Pub 2004/0091000) and Jain et al. (US 6,510,167).
Regarding claim 1, Kim et al. disclose: a fiber laser system comprising: a pump laser (7) generating a pump laser beam (Fig. 1, col. 3, lines 15-37); and a length of optical fiber (4) optically coupled to the pump laser, the length of optical fiber having: a cavity having a cavity path (cavity formed between fiber gratings 3 and 6) (Fig. 1, col. 3, lines 15-37), a first fiber Bragg grating (3) having a first reflectivity profile, a second filter (grating 6) having a second filter profile (fiber grating 3 can be tuned using a fine movement mechanism, fiber grating 3 and 6 have different peak reflectivities) (Fig. 1, col. 3, lines 15-57), and an optical gain region (erbium doped fiber 4) between the first fiber Bragg grating and the second filter along the cavity path, the first reflectivity profile being spectrally detuned from the second filter profile (fiber grating 3 can be tuned using a fine movement mechanism and can therefore be detuned from the reflectivity profile of the grating 6) (Fig. 1, col. 3, lines 15-57), the first reflectivity profile and the second filter profile being one of: spectrally non-overlapping, and spectrally overlapping only to the extent that adjacent tails of the first reflectivity profile and the second filter profile overlap with one another (Fig. 2 shows adjacent tails of the first reflectivity profile (right side of reflectivity peak of curve R1 ) and the second filter profile (left side of reflectivity peak of curve R2) overlap with one another) (Figs. 1 and 2, col. 3, lines 15 to col. 4, line 26).
Kim et al. do not disclose: laser cavity, the first fiber Bragg grating having a first refractive index profile comprising a full width at half maximum bandwidth of at least 0.2 nm and a Gaussian-like apodization, wherein, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Reed et al. disclose: at least some of the fiber Bragg gratings such that their reflectivity has full width at half maximum in the range 0.8-2.0 nm (Abstract). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim by forming the first fiber grating so that the full width at half maximum bandwidth is at least 0.2 nm in order to obtain the desired output pulse waveform.
Kim as modified do not disclose: laser cavity, a Gaussian-like apodization, wherein, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Kuksenko discloses: fiber grating with Gaussian-like apodization ([0033]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by forming the first fiber grating with Gaussian-like apodization in order to improve side mode suppression.
Kim as modified do not disclose: laser cavity, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Jain et al. disclose: mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses (Fig. 1, col. 5, lines 19-35). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by using the gratings to mode lock the laser pulses in order to output a consistent and controllable output pulse train. The device as modified disclose: a laser cavity, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Regarding claim 2, Kim as modified disclose: wherein the first reflectivity profile of the first fiber Bragg grating has a full width at half maximum bandwidth is of at least 0.5 nm (Reed, Abstract).
Kim as modified do not disclose: a maximal reflectivity value of at least 40%.
However, In accordance with MPEP 2144.05 II, Optimization of Ranges: Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In the prior art the general conditions are disclosed, a first fiber Bragg grating having a first reflectivity profile with a maximal reflectivity value. Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to obtain a workable range of values for the maximal reflectivity value of the first fiber Bragg grating by routine experimentation.
Regarding claim 3, Kim as modified do not disclose: wherein the maximal reflectivity value of the first reflectivity profile is at least 50%.
However, In accordance with MPEP 2144.05 II, Optimization of Ranges: Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In the prior art the general conditions are disclosed, a first fiber Bragg grating having a first reflectivity profile with a maximal reflectivity value. Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to obtain a workable range of values for the maximal reflectivity value of the first fiber Bragg grating by routine experimentation.
Regarding claim 4, Kim as modified do not disclose: wherein the full width at half maximum bandwidth of the first reflectivity profile is between about 4 nm and about 5 nm.
However, In accordance with MPEP 2144.05 II, Optimization of Ranges: Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In the prior art the general conditions are disclosed, a first fiber Bragg grating having a first reflectivity profile with a full width half maximum bandwidth. Therefore, it would have been obvious to one of ordinary skill in the art at the time of the invention to obtain a workable range of values for the full width half maximum bandwidth by routine experimentation.
Regarding claim 5, Kim as modified disclose: wherein the first refractive index profile has a varying grating period (chirped grating) (Kuksenko, [0033]).
Regarding claim 6, Kim as modified disclose: wherein the varying grating period of a respective one of the first and second refractive index profile varies in a linear manner, thereby offering a linear group delay dispersion across the respective one of the first reflectivity profile and the second filter profile (linear period chirp of 3 nm/cm) (Kuksenko, [0033]).
Regarding claim 9, Kim as modified disclose: wherein the second filter profile has a maximal reflectivity or transmissivity value being smaller than a maximal reflectivity value of the first reflectivity profile (reflectivity R2 of grating 6 is less than reflectivity R1 of grating 3), the output being optically coupled to the second filter (output port 8 coupled to grating 6) (Kim, Figs 1 and 2, col. 3, lines 46-50 and col. 4, lines 1-10).
Regarding claim 10, Kim as modified disclose: wherein the second filter is a second fiber Bragg grating (grating 6), the second filter profile being a second reflectivity profile spectrally detuned from the first reflectivity profile (Figs. 1 and 2, col. 3, lines 37-41, col. 4, lines 37-52).
Regarding claim 11, Kim as modified disclose: wherein the first and second fiber Bragg gratings sandwich at least a portion of the optical gain region along the cavity path, the cavity path thereby being a linear path along which the optical pulses are reflected in back-and-forth between the first and second fiber Bragg gratings (Kim, Fig. 1, col. 3, lines 15-57).
Regarding claim 16, Kim as modified do not disclose: wherein the second refractive index profile has a varying grating period.
Kuksenko discloses: chirped fiber grating with Gaussian-like apodization ([0033]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by forming the second fiber grating with a varying grating period in order to control the dispersion of the output signal.
Regarding claim 17, Kim as modified disclose: further comprising a mode locking device (fine movement mechanism) coupled to the length of optical fiber and contributing to said mode locking of said laser cavity (Kim, col. 3, lines 37-50).
Regarding claim 18, Kim as modified disclose: wherein the mode locking device has a stretching element (optical fiber grating 3 can be made tensile by means of a fine movement mechanism) longitudinally stretching at least one of the first fiber Bragg grating and the second filter, thereby modifying a spectral detuning between the first reflectivity profile and the second filter profile (Kim, col. 3, lines 37-50, col. 4, lines 37-45).
Regarding claim 25, Kim as modified do not disclose: further comprising a tilted fiber Bragg grating in the cavity path within the laser cavity.
The examiner takes official notice that a tilted fiber Bragg grating was well known in the art before the time of filing. For example, see Nicholson et al. (US 7,949,215), col. 7, lines 47-54. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by forming a tilted fiber Bragg grating in the cavity path in order to couple light orthogonally out of the fiber.
Claims 26 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 6,137,932) in view of Kuksenko (US PG Pub 2004/0091000) and Jain et al. (US 6,510,167).
Regarding claim 26, Kim et al. disclose: a laser system comprising: a pump laser (7) generating a pump laser beam (Fig. 1, col. 3, lines 15-37); a cavity optically coupled to the pump laser, the laser having a cavity path (laser cavity formed between fiber gratings 3 and 6) (Fig. 1, col. 3, lines 15-37), a first filter (grating 3) having a first filter profile, a second filter having a second filter profile, and an optical gain region (erbium doped fiber 4) between the first and second filters along the cavity path, the first and second filter profiles being spectrally detuned from one another (fiber grating 3 can be tuned using a fine movement mechanism and can therefore be detuned from the reflectivity profile of the grating 6) (Fig. 1, col. 3, lines 15-57), the first reflectivity profile and the second filter profile being one of: spectrally non-overlapping, and spectrally overlapping only to the extent that adjacent tails of the first reflectivity profile and the second filter profile overlap with one another (Fig. 2 shows adjacent tails of the first reflectivity profile (right side of reflectivity peak of curve R1 ) and the second filter profile (left side of reflectivity peak of curve R2) overlap with one another) (Figs. 1 and 2, col. 3, lines 15 to col. 4, line 26), the first filter being dispersive (a grating is dispersive) thereby imparting a dispersive profile across at least at portion of the first filter profile (Fig. 1, col. 3, lines 15-57).
Kim et al. do not disclose: a laser cavity; a first filter having a first filter profile of a Gaussian-like shape; wherein, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Kuksenko discloses: fiber grating with Gaussian-like apodization ([0033]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim by forming the first fiber grating with Gaussian-like apodization in order to improve side mode suppression.
Kim as modified do not disclose: a laser cavity; wherein, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Jain et al. disclose: mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses (Fig. 1, col. 5, lines 19-35). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by using the gratings to mode lock the laser pulses in order to output a consistent and controllable output pulse train. The device as modified disclose: a laser cavity, upon pumping of the optical gain region with the pump laser beam and mode locking of the laser cavity, optical pulses are circulated along the cavity path; and an output optically coupled to the laser cavity and outputting at least a portion of the optical pulses.
Regarding claim 29, Kim as modified disclose: wherein at least a portion of the laser cavity is fibered (Kim, Fig. 1, col. 3, lines 15-57).
Claims 27 and 28 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 6,137,932) in view of Kuksenko (US PG Pub 2004/0091000), Jain et al. (US 6,510,167) and Reed et al. (US 5,815,518),.
Regarding claim 27, Kim as modified disclose: a Gaussian-like apodization (see the rejection of claim 26).
Kim as modified do not disclose: wherein the first filter is a fiber Bragg grating has an refractive index profile comprising a full width at half maximum bandwidth of at least 0.2 nm.
Reed et al. disclose: at least some of the fiber Bragg gratings such that their reflectivity has full width at half maximum in the range 0.8-2.0 nm (Abstract). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Kim as modified by forming the first fiber grating so that the full width at half maximum bandwidth is at least 0.2 nm in order to obtain the desired output pulse waveform.
Regarding claim 28, Kim as modified disclose: wherein the refractive index profile has a varying grating period (chirped grating) (Kuksenko, [0033]).
Allowable Subject Matter
Claims 7, 8 and 23 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.
Claim 7 is allowable as the prior art fails to anticipate or render obvious the claimed limitations including “…wherein the linear group delay dispersion is steeper than ±0.5 ps2.”
Claim 8 is allowable as the prior art fails to anticipate or render obvious the claimed limitations including “…wherein the linear group delay dispersion of the varying grating period is at least twice as steep as a linear group delay dispersion offered by the optical gain region.”
Claim 23 is allowable as the prior art fails to anticipate or render obvious the claimed limitations including “…wherein the outputted optical pulses have a similariton-like profile having a linearly varying instantaneous frequency and a pulse duration below 100 fs after compression.”
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 XINNING(TOM) NIU whose telephone number is (571)270-1437. The examiner can normally be reached M-F: 9:30am-6:00pm.
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/XINNING(Tom) NIU/Primary Examiner, Art Unit 2828