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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-23 and 31 in the reply filed on September 02, 2026 is acknowledged.
Claims 24-30 and 32-41 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on September 02, 2026.
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.
Claim 7 is rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The claimed limitation “…the Zns and/or the ZnSe optically are polycrystalline” is indefinite. The examiner cannot determine if polycrystalline is a required part of the claim. For the purpose of examination, the examiner will interpret the claim to mean Zns and/or Znse are not polycrystalline.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1, 4-17, 19 and 23 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Nagl Nathalie: "A New Generation of Ultrafast Oscillators for Mid-Infrared Applications", Ludwig-Maximilians-Universität München, 30 October 2020 (2020-10-30), XP055888732, München, ISSN: 2190-5053, ISBN: 978-1-4471-4923-1, Retrieved from the Internet: URL:https://edcc.ub.uni-muenchen.de/27405/ 1/Nagl_Nathalie.pdf.
Regarding claim 1, Nagl discloses: a laser oscillator system comprising: a resonator cavity (cavity including mirrors M1, M2 and two 4f telescopes) to configured to confine an intra-cavity laser beam (Fig. 5.6, pages 100-104); a Cr-doped II-VI gain medium (Cr:Zns gain medium) arranged within the resonator cavity (Fig. 5.6, pages 100-104); and an imaging unit forming part of the resonator cavity (two 4f telescopes), wherein the imaging unit is configured to decouple a spot size of the intra-cavity laser beam at the gain medium from an intra-cavity length of the resonator cavity, and wherein the resonator cavity and the imaging unit are configured such that the laser oscillator system emits laser pulses at a repetition rate of 50 MHz or less (25 MHz) (Fig. 5.6, pages 100-104).
PNG
media_image1.png
532
668
media_image1.png
Greyscale
Fig. 5.6 of Nagl
Regarding claim 4, Nagl discloses: wherein the imaging unit comprises one or more telescopes for imaging the intra-cavity laser beam, and wherein the one or more telescopes optionally contain one or more 4 f-telescopes (two 4f telescopes) (Fig. 5.6, pages 100-104).
Regarding claim 5, Nagl discloses: wherein an end minor of the resonator cavity is arranged in one of the imaging planes of the one or more telescopes (Fig. 5.6, pages 102).
Regarding claim 6, Nagl discloses: wherein the resonator cavity and optionally the imaging unit comprise one or more multipass-cells, and wherein the one or more multipass-cells optionally comprise one or more Herriott-type cells (page 116).
Regarding claim 7, Nagl discloses: wherein the Cr-doped II-VI gain medium comprises or consists of ZnS and/or ZnSe, and wherein the ZnS and/or the ZnSe optionally are polycrystalline (Cr:Zns gain medium) (Fig. 5.6, pages 100-104).
Regarding claim 8, Nagl discloses: wherein the gain medium is oriented at a Brewster angle at the central wavelength of the intra-cavity laser beam or at a normal incidence angle of the intra-cavity laser beam (normal incidence) (Fig. 5.6).
Regarding claim 9, Nagl discloses: wherein the resonator cavity and the imaging unit are configured such that the laser oscillator system emits laser pulses at a repetition rate of 40 MHz or less (page 107).
Regarding claim 10, Nagl discloses: wherein the laser oscillator system is configured to emit the laser pulses having a pulse duration of 30 fs FWHM or less and/or a peak power of at least 0.75 MW and optionally of at least 1 MW (peak power of 1 MW) (page 113).
Regarding claim 11, Nagl discloses: wherein the emitted laser pulses cover a spectral range from at least 2.0 μm to 2.8 μm (Fig. 5.23, page 127).
Regarding claim 12, Nagl discloses: wherein the laser oscillator system is configured as a Kerr-lens mode-locked laser oscillator system (pages 102-103).
Regarding claim 13, Nagl discloses: wherein the gain medium is configured to provide a functionality of a Kerr medium for Kerr-lens mode locking (pages 102-103).
Regarding claim 14, Nagl discloses: further comprising a Kerr medium, wherein the Kerr medium is provided separately from the gain medium (pages 115-116).
Regarding claim 15, Nagl discloses: wherein the Cr-doped II-VI gain medium is directly diode-pumped (Fig. 5.6, pages 100-101).
Regarding claim 16, Nagl discloses: wherein the laser oscillator system is configured to emit laser pulses having a peak power of at least 0.75 MW; a nonlinear optical element (ZGP) having a thickness of 1 mm or less (pages 117-118); wherein the laser system is configured to irradiate the nonlinear optical element with the laser pulses emitted by the laser oscillator system to spectrally broaden the laser pulses such that the spectrally broadened laser pulses span at least half an optical octave (Fig. 5.23, page 123).
Regarding claim 17, Nagl discloses: wherein the laser system is configured to focus the laser pulses onto the nonlinear optical element (pages 117-119).
Regarding claim 19, Nagl discloses: wherein the nonlinear optical element comprises an anti-reflection coating at the surface facing the incident laser pulses (broadband AR coating) (page 124).
Regarding claim 23, Nagl discloses: further comprising a second nonlinear optical element for spectral broadening in the mid-infrared spectral range, wherein the second nonlinear optical element optionally comprises or consists of ZnGeP2, and wherein the laser system is configured such that the laser pulses propagating through the second nonlinear optical element experience nonlinear frequency conversion (page 117).
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 2 and 3 are rejected under 35 U.S.C. 103 as being unpatentable over Nagl Nathalie: "A New Generation of Ultrafast Oscillators for Mid-Infrared Applications", Ludwig-Maximilians-Universität München, 30 October 2020 (2020-10-30), XP055888732, München, ISSN: 2190-5053, ISBN: 978-1-4471-4923-1, Retrieved from the Internet: URL:https://edcc.ub.uni-muenchen.de/27405/ 1/Nagl_Nathalie.pdf in view of Holton (US PG Pub 2011/0170566).
Regarding claim 2, Nagl does not explicitly disclose: wherein the imaging unit is configured to provide a tunable intra-cavity length.
Holton discloses: adjusting cavity length by adjust cavity mirror separation ([0085]). 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 Nagl by designing the cavity to be adjustable in order to adjust the pulse width of the device.
Regarding claim 3, Nagl as modified disclose: wherein the spot size of the intra-cavity laser beam at the gain medium is adjustable (as cavity length is changed, beam spot size in the gain medium tends to increase because beam size is a function of cavity geometry. The increased beam spot size is associated with increased laser output power in mode locked operation.) (Holton, [0085]).
Claims 18 and 31 are rejected under 35 U.S.C. 103 as being unpatentable over Nagl Nathalie: "A New Generation of Ultrafast Oscillators for Mid-Infrared Applications", Ludwig-Maximilians-Universität München, 30 October 2020 (2020-10-30), XP055888732, München, ISSN: 2190-5053, ISBN: 978-1-4471-4923-1, Retrieved from the Internet: URL:https://edcc.ub.uni-muenchen.de/27405/ 1/Nagl_Nathalie.pdf.
Regarding claim 18, Nagl does not disclose: wherein the laser system is configured such that the spectrum of the laser pulses supports a pulse duration of 15 fs or less after propagating through the nonlinear optical element.
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 laser system configured to irradiate a nonlinear optical element, the laser system outputs a laser pulse having a pulse duration after propagating through the nonlinear optical element. 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 pulse duration by routine experimentation.
Regarding claim 31, Nagl discloses: a method for generating supercontinuum light pulses, the method comprising: utilizing the a laser system according to claim 16, wherein the supercontinuum light pulses cover a spectral range at least from 1.5 μm to 3.5 μm (page 91).
Nagl does not disclose: have a pulse duration of 15 fs FWHM or less.
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 laser system used to generate supercontinuum light pulses, the light pulses having a pulse duration. 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 FWHM of the pulse duration by routine experimentation.
Claims 20 -22 are rejected under 35 U.S.C. 103 as being unpatentable over Nagl Nathalie: "A New Generation of Ultrafast Oscillators for Mid-Infrared Applications", Ludwig-Maximilians-Universität München, 30 October 2020 (2020-10-30), XP055888732, München, ISSN: 2190-5053, ISBN: 978-1-4471-4923-1, Retrieved from the Internet: URL:https://edcc.ub.uni-muenchen.de/27405/ 1/Nagl_Nathalie.pdf in view of Chuang et al. (US PG Pub 2021/0389643) and Ma (CN 111725298 A).
Regarding claim 20, Nagl does not disclose: wherein the nonlinear optical element is arranged in a Brewster angle with respect to a direction of incidence of the laser pulses at a central wavelength of the laser pulses, and wherein the nonlinear optical element is formed of a birefringent crystal cut at an angle, such that a k-vector of the incident laser pulses is parallel to an optical axis of the birefringent crystal.
Chuang et al. disclose: nonlinear optical element is arranged in a Brewster angle ([0062]). 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 Nagl by orienting the nonlinear optical element so that the input face and output face are at a Brewster angle with respect to a direction of incidence of the laser pulses in order to reduce reflections at the input and output faces.
Nagl as modified do not disclose: wherein the nonlinear optical element is formed of a birefringent crystal cut at an angle, such that a k-vector of the incident laser pulses is parallel to an optical axis of the birefringent crystal.
Ma discloses: the rutile titanium dioxide used as a nonlinear material (page 2 of translation). 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 Nagl as modified by using rutile titanium dioxide as the nonlinear element in order to improve optical confinement of the input laser pulses. The device as modified disclose: wherein the nonlinear optical element is formed of a birefringent crystal cut at an angle, such that a k-vector of the incident laser pulses is parallel to an optical axis of the birefringent crystal.
Regarding claim 21, Nagl as modified disclose: wherein the nonlinear optical element comprises or consists of TiO2 (see the rejection of claim 20).
Regarding claim 22, Nagl as modified disclose: wherein the nonlinear optical element comprises or consists of rutile TiO2 (see the rejection of claim 20).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. Franjic et al. (US PG Pub 2006/0153254) disclose: a laser system capable of efficient production of high energy sub-nanosecond pulses in the 2-15 .mu.m spectral region is disclosed. Diode pumped solid state lasers are used as pump sources. The system design is simple, reliable and compact allowing for easy integration. The laser system includes a combination of compact solid-state .about.1 micron laser sources, producing high power picosecond pulses, with optical parametric amplification and a quasi-continuous wave laser for seeding the amplification process that enables the efficient conversion of the high power .about.1 micron laser radiation to tuneable mid-infrared sub-ns pulses. New parametric processes are presented for achieving high gains in bulk nonlinear crystals. Furthermore, a method of exceeding the fundamental conversion efficiency limit of direct three wave mixing is presented. The compact and robust nature of this novel laser system opens up the use of high power and high peak power mid-infrared laser pulses to a wide variety of important medical and dental applications. Zanger et al. (US PG Pub 2006/0176916) disclose: An optically pumped, in particular diode-pumped, continuous solid-state laser produces a primary laser beam whose frequency is converted into the visible or ultraviolet spectral range by means of one or more downstream passive resonators with non-linear crystals. At relatively low cost and complication it is provided that precisely two longitudinal laser modes of approximately equal amplitude are excited in the laser resonator. That achieves a high level of efficiency for the overall system and a very low noise level of the resulting frequency-converted laser beam. In one embodiment of the invention the frequency-converted radiation contains three or more adjacent frequencies. In another embodiment of the invention the frequency-converted laser radiation contains only one single frequency and therefore corresponds to the radiation of a monomode laser (Abstract).
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.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Minsun Harvey can be reached at 571-272-1835. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/XINNING(Tom) NIU/Primary Examiner, Art Unit 2828
