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 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.
DETAILED ACTION
Claim Rejections - 35 USC § 103
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1 – 4, 6 – 12, and 14 – 20 are rejected under 35 U.S.C. 103 as being unpatentable over Tekolste et al (US 2022/0283371 A1) in view of Schmulen et al (US 2021/0341744 A1).
Regarding claim 11, Tekolste discloses (Figs. 38E; para. 0356 – 0363) a waveguide combiner, comprising (see annotated Fig. 38E below):
a substrate 3810 (para. 0356);
a first device material layer 3812 disposed over the substrate 3810 (a corresponding step is shown in Fig. 33, wherein a first device material layer 3307 disposed over a substrate 3305), the first device material layer 3812 comprising a material (with a higher refractive index, e.g., Si3N4; para. 0328) different from that of the substrate (e.g., glass; para. 0328), wherein a first (left) portion of the first device material layer 3812 comprises a grating 3816 that disposed/formed (e.g., by etching; para. 0328) in the first device material layer 3812 and is configured as a combined pupil expander 3816 (para. 0357); and
a second device material layer disposed on a portion of a top surface of a second (right) portion of the first device material layer 3812, the second device material layer having an input coupling grating 3814 disposed therein, the input coupling grating 3814 having a plurality of blazed device structures (as seen in Fig. 38E; note that, while a single grate is shown, a grating must have a plurality of grates for proper operation by interference; “Diffractive structures, including incoupling grating 3814 and combined pupil expander 3816, which includes variable height nanofeatures in this embodiment,
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are formed on variable thickness film 381” at para. 0357).
Annotated Fig. 38E of Tekolste.
Tekolste states that the grating 3816 is configured as a combined pupil expander and is used for outcoupling light that is launched in a waveguide (defined by the layer 3812) by the input coupling grating 3814 (“outcoupling by combined pupil expander 3816” at para. 0357), but Tekolste does not detail structural particulars of such combined pupil expander with the outcoupling functionality, even though they are well known in the art. For example, Schmulen discloses (Fig. 9C; para. 0114 – 0119) a waveguide combiner comprising an input coupling gratin 700 (para. 0103) and a combined pupil expander 730,800, wherein the latter comprises an output grating 800 disposed adjacent to an intermediate grating 730 (beam expander; “the light distributing elements 730, 740, 750 are orthogonal pupil expanders (OPE's). In some embodiments, the OPE's deflect or distribute light to the out-coupling optical elements 800, 810, 820 and, in some embodiments, may also increase the beam or spot size of this light as it propagates to the out-coupling optical elements” at para. 0113).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the combined pupil expander 3816 in Tekolste can comprise an output grating disposed adjacent to an intermediate grating, as generally rendered obvious by the teachings of Tekolste and expressly taught and explicitly illustrated by Schmulen, in order to enable both functionalities beam expansion and outcoupling, as required by Tekolste (para. 0357).
In light of the foregoing analysis, the Tekolste – Schmulen combination teaches expressly or renders obvious all of the recited limitations.
Regarding claim 1, the teachings of Tekolste and Schmulen combine (see the arguments and motivation for combining, as provided above for claim 1) to teach expressly or render obvious all of the recited step limitations of a corresponding method of forming the contemplated optical device, as detailed above for claim 1. Specifically, the Tekolste – Schmulen combination considers a method for forming an optical device, comprising:
disposing a first device material layer (3812 in Fig. 38E which corresponds to 3307 in Fig. 33) over a substrate (3810 in Fig. 38E; 3305 in Fig. 33), the first device material layer being a different material (e.g., Si3N4) from that of the substrate (e.g., glass; para. 0328);
patterning a (left) portion of the first device material layer 3812 to form a first plurality of device structures 3816 (combined pupil expander) in a top surface of the first device material layer 3812 (as shown in Fig. 38E), the first plurality of device structures 3816 comprising a first plurality of gratings (intermediate beam expander grating 730, as detailed by Schmulen in Fig. 9C) and a second plurality of gratings (outcoupling grating 800, as detailed by Schmulen in Fig. 9C);
disposing a second device material layer on the top surface of an unpatterned portion of the first device material layer 3812, the second device material layer being an uncured imprintable material (e.g., uncured polymeric resin (“In some implementations, the base material can include a cyclic aliphatic epoxy containing resin can be cured using ultraviolet light and/or heat. Further, the base polymer material can include an ultraviolet cationic photoinitiator and a co-reactant to facilitate efficient ultraviolet curing in ambient conditions” at para. 0326); and
patterning the second device material layer (by nanoprinting; “process 3432 can be utilized to imprint diffraction patterns on varied thickness film 3408” at para. 0334; “nanoimprint” at para. 0299; also para. 0329, 0336, 0334, and 0345) to form a second plurality of device structures in the second device material layer, the second plurality of device structures comprising a third plurality of gratings 3814,wherein the third plurality of gratings 3814 comprises a plurality of blazed device structures (as in Fig. 38E of Tekolste and in Fig. 19B of Schmulen) or a plurality of staircase device structures (as in Fig. 19C of Schmulen), and each of the third plurality of gratings 3814 comprises a grating depth extending from the top surface of the first device material layer 3812 to a top surface of each of the respective third plurality of gratings 3814.
Regarding claims 2 and 3, the Tekolste – Schmulen combination considers that the first plurality of gratings correspond to a pupil expansion grating (corresponds to 730 in Fig. 9C of Schmulen) of a waveguide combiner and the second plurality of gratings correspond an output coupling grating (corresponds to 800 in Fig. 9C of Schmulen) of the waveguide combiner, wherein the third plurality of gratings (3814 in Fig. 38E of Tekolste which corresponds to 700 in Fig. 9C of Schmulen) correspond to an input coupling grating of a waveguide combiner.
Regarding claims 4, 14, and 18, the Tekolste – Schmulen combination considers disposing a reflective metal coating (1010 in Figs. 19C and 19C of Schmulen; “a reflective layer 1010 is disposed over an optical grating 1020 (See, e.g., FIGS. 19A-19C)” at para. 0163 of Schmulen; “the reflective layer (e.g., the metal layer) formed” at para. 0160; also para. 0161 and 0164) on the third plurality of gratings.
Regarding claims 6, 7, and 17, the Tekolste – Schmulen combination considers that the first device material layer 3812 (in Fig. 38E which corresponding to 33076 in Fig. 33) comprises a high-index film material, such as silicon nitride (Si3N4), titanium dioxide (TiO2), zirconium dioxide (ZrO2), and zinc oxide (ZnO), having a refractive index between ~ 1.42 and ~ 2.7 (“The thin film coating, referred to as a film herein, can have a similar index of refraction to that of the substrate, for example, silicon oxynitiride (SixOyNz) with an index of refraction in the range of ~ 1.42 to ˜2.0. Additionally, films of ZnO, ZrO2, TiO2, SiC, and the like can be utilized to achieve index of refraction values in the range of ~2.0 to ~ 2.7” at para. 0326 of Tekolste).
Hence, the Tekolste – Schmulen combination considers a range of refractive index values that at least overlaps with the recited range and a prima facie case of obviousness exists (MPEP 2144.05). The Examiner notes that (i) the range limits depend on a particular application; that (ii) the instant application does not provide any criticality for the exact values of the recited range limits; that (iii) it has been held that discovering the optimum or workable ranges of prior art involves only routine skill in the art (In re Aller, 105 USPQ 233); that (iv) it has been held that "A recognition in the prior art that a property is affected by the variable is sufficient to find the variable result-effective." In re Applied Materials', Inc., 692 F.3d 1289, 1297 (Fed. Cir. 2012). It is well settled that it would have been obvious for an artisan with ordinary skill to develop workable or even optimum ranges for result-effective parameters. In re Boesch, 617 F.2d 272, 276 (CCPA 1980); see also In re Woodruff, 919 F.2d 1575, 1577-78 (Fed. Cir. 1990). The Tekolste – Schmulen combination regards the refractive index of first device layer as an result-effective parameter (affecting waveguide properties and diffraction efficiency of the gratings).
Regarding claims 8 and 9, the Tekolste – Schmulen combination considers that the second device material layer (for the input coupling grating 3814 in Fig. 38E of Tekolste) comprises a UV curable adhesive/ polymer or a thermally curable polymer material (“In some implementations, the base material can include a cyclic aliphatic epoxy containing resin can be cured using ultraviolet light and/or heat. Further, the base polymer material can include an ultraviolet cationic photoinitiator and a co-reactant to facilitate efficient ultraviolet curing in ambient conditions” at para. 0326 of Tekolste, emphasis added).
Regarding claims 10 and 16, the Tekolste – Schmulen combination considers that the intermediate grating and the output coupling grating (disposed within 3816 in Fig. 38E of Tekolste and corresponding top 730 and 800 in Fig. 9C of Schmulen) can be formed by performing a lithographic patterning and etch process in the first (left) portion of the first device material layer 3812 (“the films can be shaped in a manner similar to those shown in FIG. 33 using, for example, dry etching methods like reactive ion etching (RIE), Inductively Coupled Plasma enhanced RIE (RIE-ICP), or ion beam etching (IBE)’ at para. 0326 of Tekolste; “The coating or the etched profile can then be patterned using imprint lithography or photolithography to form a diffraction pattern” at para. 0336; “a diffractive structure etched or otherwise formed in variable thickness film 3812” at para. 0361).
Regarding claim 12, the Tekolste – Schmulen combination considers that the input coupling grating (3814 in Fig. 38E of Tekolste) comprises a grating depth extending from the top surface of the first device material layer to a top surface of the input coupling grating (Fig. 38E of Tekolste; Figs. 19B and 19C of Schmulen).
Regarding claim 15, the Tekolste – Schmulen combination considers that the second device material layer is disposed on the second (right) portion of the first device material layer 3812 and can comprise an imprintable material (e.g., uncured polymeric resin; “In some implementations, the base material can include a cyclic aliphatic epoxy containing resin can be cured using ultraviolet light and/or heat. Further, the base polymer material can include an ultraviolet cationic photoinitiator and a co-reactant to facilitate efficient ultraviolet curing in ambient conditions” at para. 0326) that is processed/shaped by a nano imprint lithography process (“process 3432 can be utilized to imprint diffraction patterns on varied thickness film 3408” at para. 0334; “nanoimprint” at para. 0299; “The coating or the etched profile can then be patterned using imprint lithography or photolithography to form a diffraction pattern” at para. 0336; also para. 0329, 0334, and 0345).
Regarding claims 19 and 20, the Tekolste – Schmulen combination considers that the intermediate grating and the output coupling grating (both disposed with combined pupil expander 3816 in Fig. 38E of Tekolste) each comprises lines (binary).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Tekolste in view of Schmulen, in view of Yang et al (US 2021/0041611 A1), and further in view of Sadeghi et al (US 2023/0393325 A1).
Regarding claim 5, the Tekolste – Schmulen combination considers that the second device material layer is disposed on the second (right) portion of the first device material layer 3812 and can comprise an imprintable material (e.g., uncured polymeric resin; “In some implementations, the base material can include a cyclic aliphatic epoxy containing resin can be cured using ultraviolet light and/or heat. Further, the base polymer material can include an ultraviolet cationic photoinitiator and a co-reactant to facilitate efficient ultraviolet curing in ambient conditions” at para. 0326) that is processed/shaped by a nano imprint lithography process (“process 3432 can be utilized to imprint diffraction patterns on varied thickness film 3408” at para. 0334; “nanoimprint” at para. 0299; “The coating or the etched profile can then be patterned using imprint lithography or photolithography to form a diffraction pattern” at para. 0336; also para. 0329, 0334, and 0345). While Tekolste does not detail such process of nano printing, its particulars are well known in the art. For example, Yang discloses (Figs. 13, 21, 22, and 26; Abstract; para. 0118 – 0120 and 0150 – 0167) a nano imprint lithography process for making blazed input coupling gratings and/or blazed output grating gratings (para. 0167) by either direct imprinting (para. 0118) or an imprinted photoresist mask followed by etching (para. 0119), both processes using a master stamp (2104,2116 in Fig. 21; 2204,2212,2220,2116 in Fig. 22) with an inverse/mirrored grating pattern.
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that a nano imprint lithography process, as considered by Tekolste, can use a master stamp, as a means for implementing such imprint process, as generally rendered obvious by Tekolste and expressly taught and explicitly illustrated by Yang.
The Tekolste – Schmulen – Yang combination considers a process wherein patterning the second device material layer (corresponding to 3814 in Fig. 38E of Tekolste and comprising an uncured polymer/epoxy; para. 0326 of Tekolste) comprises patterning with a nano imprint lithography process comprising:
imprinting a master stamp (explicitly illustrated by Yang) into the second device material layer, the imprinting master stamp comprising a plurality of inverse gratings inverse of the third plurality of gratings of the second plurality of device structures (explicitly illustrated by Yang);
subjecting the second device material layer to a cure process (by UV or heat; para. 0326 of Tekolste); and
releasing the master stamp from the second device material layer (explicitly illustrated by Yang).
Schmulen mentions (para. 0149) the use of annealing to improve adhesion of a reflective metal coating on a grating, but the Tekolste – Schmulen – Yang combination does not expressly teach a (final) step of subjecting the second device material layer to an anneal process. However, Sadeghi discloses (para. 0093, 0102, 0103, 0112, and 0124) a process of nano imprinting a patterned thin film of material (para. 0124), the proceeds comprising a step of exposing and curing the material by UV followed by a step of annealing (para. 0102 and 0103).
It would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention that the process of the Tekolste – Schmulen – Yang combination can further comprise, as a final step, subjecting the second device material layer to an anneal process, as expressly taught by Sadeghi, in order to completely solidify the second device material layer and improve its hardness and adhesion.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 2018/0113313 A1 Figs. 2,9
US 10,481,317 B2 Figs. 118,119,124
US 11,435,528 B1 Fig. 12
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT TAVLYKAEV whose telephone number is (571)270-5634. The examiner can normally be reached 10:00 am - 6:00 pm, Monday - Friday.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, William Kraig can be reached on (571)272-8660. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ROBERT TAVLYKAEV/Primary Examiner, Art Unit 2896
