The arguments submitted 09/12/2025 have been considered. The merits of the claims, however, remain unpatentable over the prior art as set forth below.
Claim Interpretation
The following is a quotation of 35 U.S.C. 112(f):
(f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.
The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked.
As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph:
(A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function;
(B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and
(C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function.
Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function.
Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function.
Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action.
This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are:
a device for adjusting the orientation of the laser radiation emitted by the monolithic mode-locked laser diode
a device for adjusting the intensity of the laser radiation emitted by the monolithic mode-locked laser diode
Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof.
If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph.
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, 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 1-3 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Surkamp (“Mode-locked diode lasers as sources for two-photon polymerization”; Surkamp N, Zyla G, Gurevich E L, Esen C, Klehr A, Knigge A, Ostendorf A, Hofmann M R; SPIE Proceedings; 20200414; pp. 113490G1-113490G-8, previously made of record on an IDS filing) in view of Matheu (US PG Pub 2018/0257297) and Peng (CN 106853554A, with text citations to attached translation).
Regarding claim 1, Surkamp teaches a laser system for producing an object by way of two-photon polymerization (Abstract, section 2.1), comprising:
a monolithic mode-locked laser diode (“a hybrid mode-locked double quantum well laser diode” per the first sentence of section 2.1, wherein it is implicit that the micron scale layers can only be fabricated monolithically),
a microscope objective that is configured and arranged to focus laser radiation generated by the monolithic mode-locked laser diode (second paragraph in Abstract).
Surkamp does not explicitly teach that the laser system is a write head.
However, the use of a write head for producing an object by way of two-photon polymerization and using a laser and microscope objective is known in the prior art, as taught for example by Matheu (paras. 0003 and 0134; and 110 in Fig. 1).
Furthermore, in the absence of any unexpected results, the courts have found that making an integral one-piece article from separate items is prima facie obvious to one of ordinary skill in the art. See MPEP § 2144.04.V.B and In re Larson, 340 F.2d 965, 968, 144 USPQ 347, 349 (CCPA 1965).
In view of Matheau’s teachings and the considerations above, it would have been obvious to one of ordinary skill in the art at the time of filing to modify Surkamp’s laser system to place the laser diode, microscope objective, and the other optical elements in a write head to predictably obtain an integral and/or more compact system for producing an object via two-photon polymerization.
Neither Surkamp nor Matheau explicitly teaches the monolithic mode-locked laser diode has a pulse duration in the range from 2 picoseconds to 10 picoseconds. However, Surkamp teaches that the output of the monolithic mode-locked laser diode is “guided...and compressed in a single pass grating compressor resulting in…a pulse duration of 440 fs”, which implies that the laser pulse duration prior to directing the beam through the single pass grating compressor must be longer than the 440 fs duration resulting after the beam passes through the single pass grating compressor.
In addition, it is known in the prior art, as taught for example by Peng, that lasers with ultra-short pulse duration in the picosecond range (“Ultra-short pulse lasers include femtosecond lasers and picosecond lasers with pulse widths less than 10 picoseconds” per the last paragraph on pg. 1 with emphasis added by examiner) are useful for two-photon polymerization to achieve cold fine processing (“the use of cold laser, such as the use of ultra-short pulse laser treatment of brittle materials do not produce thermal effects, no heat affected zone (HAZ)” per the last paragraph on pg. 1 with emphasis added by examiner) and high precision in 3D materials (“…There are two ways of material processing and processing using ultrashort pulsed lasers: material modification and material ablation (ablation). The material modification is the local absorption of femtosecond laser after the refractive index changes, the use of two-photon polymerization and photochemical reaction mechanism to achieve fine processing” per the last paragraph on pg. 1). In particular, Peng teaches that a pulse duration of 0.2 to 10 ps is useful in these laser systems (11th paragraph on pg. 2 and claim 3), thus encompassing the claimed range and rendering it obvious. A prior art range which encompasses, partially overlaps, or touches the claimed range is sufficient to establish a prima facie case of obviousness, in the absence of any unexpected results. See MPEP § 2144.05.I and In re Harris, 409 F.3d 1339, 74 USPQ2d 1951 (Fed. Cir. 2005); In re Peterson, 315 F.3d 1325, 1330, 65 USPQ2d 1379, 1382-83 (Fed. Cir. 2003).
In view of the teachings of Surkamp and Peng, it would have been obvious to one of ordinary skill in the optical polymerization arts to modify Surkamp’s laser system and the write head of Surkamp as modified by Matheau by simply omitting Surkamp’s single pass grating compressor and instead utilizing a monolithic mode-locked laser diode with a pulse duration of 2 to 10 picoseconds to predictably obtain a write head suitable for cold, high resolution processing of materials without adverse thermal effects or heat damage. Furthermore, this modification predictably provides the additional advantage of a reduced size footprint for the laser system, thereby providing space savings and/or reduction of size needed for the write head containing the laser diode.
Regarding claim 2, Surkamp teaches a camera and a beam splitter that is configured and arranged to allow the laser radiation emitted by the monolithic mode-locked laser diode to pass through and to deflect counter-propagating radiation to the camera (second paragraph in Abstract).
Regarding claims 3 and 11, Surkamp teaches a device for adjusting the orientation of the laser radiation emitted by the monolithic mode-locked laser diode (2D galvo-scanner in first sentence of the second paragraph in Abstract).
Claims 4-5 and 12-16 are rejected under 35 U.S.C. 103 as being unpatentable over Surkamp in view of Matheu and Peng, as applied to claim 1 (and 2 for claims 12-13) above, further in view of Saha (US PG Pub 2019/0126537).
Regarding claims 4, 12, and 14, Surkamp, Matheu, and Peng do not explicitly teach this feature.
However, Saha teaches a laser system for producing an object by way of two-photon polymerization comprising a device for adjusting the intensity of the laser radiation emitted by the laser (neutral density filter of para. 0048).
In view of Saha’s teachings and/or KSR rationale A, it would have been obvious to combine Saha’s ND filter(s) with the write head of Surkamp in view of Matheu and Peng to predictably obtain this capability for irradiation power control and adjustment.
Regarding claims 5, 13, and 15-16, Surkamp, Matheu, and Peng do not explicitly teach this feature.
However, Saha teaches the laser system comprises collimating optics between the laser and the microscope objective (collimating lenses 114 and 115 in Fig. 2).
In view of Saha’s teachings and/or KSR rationale A, it would have been obvious to combine Saha’s collimating optics with the write head of Surkamp in view of Matheu and Peng to predictably obtain beam collimating for compatibility with the objective.
Response to Arguments
Applicant's arguments filed 09/12/2025 have been fully considered and are not persuasive for the reasons given below. It is noted that Applicant’s remarks include citations to four non-patent references which have not been supplied by Applicant. Therefore, these NPL references have not been fully considered in this response.
Regarding claim 1, Applicant presents a line of argument contending that pulse durations of 2-10 picoseconds are not known in the prior art to be useful for two-photon polymerization and instead are useless for two-photon polymerization on the basis of the record as a whole (Remarks sections 1-4 and 9).
However, this line of argument is not persuasive for the following reasons. First, this line of argument completely ignores Peng’s explicit teachings about the utility of laser pulses of 0.2 to 10 picoseconds to produce two-photon polymerization and the benefits thereof, as described in the rejection above, which would have made use of a picosecond laser an obvious modification to Surkamp. Secondly, the utility and advantages of picosecond laser pulse durations for write systems to produce an object by two-photon polymerization have, in fact, been recognized by others in the prior art. For example, Malinauskas (“Three-dimensional micro-/nano-structuring via direct write polymerization with picosecond laser pulses”, Optics Express, Vol. 19, No. 6, March 2011, pp. 5602-5610, and made of record herein) teaches that “the two-photon nonlinear absorption is still distinguishable at … shorter pulses (≤ 8 ps)” per the abstract on pp. 5602, with such picosecond laser systems providing the advantages of lower cost and smaller footprint per Section 4: Conclusions on pp. 5610, in comparison to femtosecond laser systems.
Regarding claim 1, Applicant presents a line of argument contending that Surkamp does not teach a mode-locked laser diode (Remarks sections 5-6).
However, this line of argument is not persuasive because it completely ignores Surkamp’s explicit teachings of a mode-locked laser diode, as described in the rejection above.
Regarding claim 1, Applicant presents a line of argument contending that Surkamp does not teach that the mode-locked laser diode is monolithic (Remarks section 7).
However, this argument is not persuasive for the following reasons. First, no special definitions have been given in the disclosure for the term monolithic mode-locked laser diode. Thus, in the absence of any special definitions, claims must be “given their broadest reasonable interpretation consistent with the specification” and therefore a prior art reference does not need to satisfy an ipsissimis verbis test. See MPEP § 2111 and In re Bond, 910 F.2d 831, 15 USPQ2d 1566 (Fed. Cir. 1990) for further details. Surkamp teaches that the mode-locked laser diode is a double quantum well laser diode with a 1080 micron thick gain section (first sentence of section 2.1), and it is well-known that quantum well laser diodes are a type of monolithic laser diode, as evidenced by para. 0093 in Liu (US PG Pub 2012/0239016, made of record previously). Furthermore, double quantum well laser diodes are necessarily monolithic because they require very thin (e.g. typically microns scale or smaller) layers of differing semiconductor materials in a stack to form the quantum wells, which provide quantum confinement effects, as taught for example, by para. 0066 of Zachreson (US PG Pub 2019/0013178, made of record previously), and which can only be fabricated by sequential depositions of these layers on a substrate (e.g. per para. 0067), thus implicitly forming a monolithic device.
Regarding claim 1, Applicant presents a line of argument contending that the rejection relies upon the notion that Surkamp’s laser diode inherently outputs laser pulses with a duration longer than the 440 femtosecond pulses which are output by Surkamp’s single pass grating compressor and that without this notion substitution of a mode-locked laser producing longer picosecond pulses would not have been obvious (Remarks sections 8-9).
However, this line of argument is not persuasive for the following reasons. First, the rejection above does not state or rely upon the notion that Surkamp’s laser diode inherently outputs laser pulses with a duration longer than the 440 femtosecond pulses, but instead simply points out that the laser pulse duration prior to directing the beam through a single pass grating compressor is longer than the 440 fs resulting from directing the beam through a single pass grating compressor which compresses the pulse duration. Secondly, regardless of what the duration of Surkamp’s laser pulses are prior to being passed through the single pass grating compressor, one of ordinary skill in the art would have been motivated to substitute a picosecond laser from Peng’s teachings of the benefits thereof, as cited in the rejection above.
Regarding claim 1, Applicant presents a line of argument contending that Surkamp’s mode-locked laser diode is not monolithic because Surkamp teaches the laser diode is used with an external cavity (Remarks section 10).
However, this line of argument is not persuasive because claim 1 does not, in fact, exclude the combination of a monolithic mode-locked laser diode together with an external cavity in the write head for the following reasons: First, the monolithic mode-locked laser diode in the Surkamp reference, and indicated as component LD in Fig. 1 of the journal article "Mode-locked diode laser-based two-photon polymerization", previously made of record on the IDS filed 2/16/23 and cited within the Surkamp reference, is a complete and fully-functioning laser diode (LD) producing laser light, as evidenced by Fig. 2 in the article "What is a Quantum Well Laser", previously made of record. This laser light is then fed into the external cavity shown to the right of the laser diode in Fig. 1 of the journal article for further refinement. Secondly, the preamble of claim 1 recites "Write head...comprising:", and the term comprising is open-ended and allows other components besides the ones recited in the claim to be present.
Regarding claim 1, Applicant presents a line of argument contending that modifying Surkamp’s apparatus to make a more compact apparatus is not suggested by the prior art viewed as a whole and would render the write head of Surkamp in view of Matheu more difficult to move precisely and quickly (Remarks sections 11-13).
However, this line of argument is not persuasive for the following reasons. First, the desirability of making a more compact apparatus for producing an object by two-photon polymerization is known in the prior art, as evidenced by Malinauskas, and readily appreciated by an engineer of ordinary skill in the art. Secondly, the claim does not recite that the write head must move precisely and quickly and define what is meant by moving precisely and quickly.
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.
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/JRS/
Examiner
Art Unit 1745
/PHILIP C TUCKER/Supervisory Patent Examiner, Art Unit 1745