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 .
Claim Objections
Claims 1 and 9–12 are objected to because of the following informalities: the term “granting” should be “grating”. It appears to be a typographical error. Appropriate correction is required.
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 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:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
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 1–8, 13, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over U.S. Patent Application Publication No. 2023/0359050 to Glik et al.1 in view of CN 113721320 A to Sun, et al. (machine translation attached with this Office action, citations are to the provided translation).
Regarding Claim 1, Glik discloses (e.g., Fig. 4 and its description) a grating structure, comprising a base 402, and a plurality of grating portions 404 provided on a surface of the base, the plurality of grating portions being arranged at intervals along an extension direction of the base (Fig. 4; paragraphs [0014], [0016], and [0036], periodic structure), wherein a surface of each of the plurality of grating portions comprises an enhancement layer 406 whose refractive index is greater than a refractive index of the plurality of grating portions (paragraph [0032]).
Glik does not explicitly disclose that the enhancement layer of a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions.
Sun discloses a diffractive optical waveguide useful for VR/AR devices, similar to Glik, and Sun teaches that an enhancement layer 40 has a varying thickness in order to achieve homogenization and a uniform display in the final image (e.g., Fig. 4 and its description including paragraphs [n0049]–[n0050]).
It would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the device of Glik such that the enhancement layer of a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions, as suggested by Sun, for improved display uniformity.
Regarding Claim 2, the combination of Glik and Sun would have rendered obvious wherein in an arrangement direction of the plurality of grating portions, the thickness of the enhancement layer on the surfaces of the plurality of grating portions gradually increases (paragraph [n0050] of Sun, “the thickness of the multiple homogenizing regions of the homogenizing film layer 40 on the folding grating 20 gradually decreases along the direction away from the coupling grating 10”).
Regarding Claim 3, the combination of Glik and Sun would have rendered obvious wherein the surface of each of the plurality of grating portions comprises a top portion parallel to the surface of the base and a side portion connecting the top portion to the surface of the base, and the enhancement layer on the top portion and the side portion differs in thickness (e.g., Figs. 4, 6, and 7 of Sun).
Regarding Claim 4, the combination of Glik and Sun would have rendered obvious wherein in an arrangement direction of the plurality of grating portions, height of the grating portions is greater than width of the plurality of grating portions, and thickness of the enhancement layer coated on the top portion is greater than thickness of the enhancement layer on the side portion (e.g., Figs. 4, 6, and 7 of Sun, also where selecting the specific relative thicknesses would have been obvious as a matter of design choice, based on desired homogenization, yielding predictable results, as suggested by paragraphs [n0049]–[n0050] of Sun, absent evidence of criticality or otherwise unobvious results from the claim features).
Regarding Claim 5, the combination of Glik and Sun would have rendered obvious wherein the enhancement layer is made of one of titanium dioxide, aluminum oxide, and magnesium oxide (paragraph [n0055] of Sun).
Regarding Claim 6, the combination of Glik and Sun would have rendered obvious wherein thickness of the enhancement layer coated on the surfaces of the plurality of grating portions ranges from 20nm to 30nm (e.g., paragraph [n0054] of Sun, teaching an overlapping range).
Regarding Claim 7, the combination of Glik and Sun would have rendered obvious wherein the enhancement layer is configured to be coated through Atomic Layer Deposition, Chemical Vapor Deposition, Physical Vapor Deposition, or Magnetron Sputtering (e.g., paragraph [n0056] of Sun).
Regarding Claim 8, the combination of Glik and Sun would have rendered obvious wherein the base is made of silica or resin (paragraph [0031] of Glik); and/or, the plurality of grating portions are made of silica or resin (paragraph [0031] of Glik); and/or, the grating structure is a binary grating, a blazed grating, an inclined grating, or a multi-step grating (paragraph [0016] of Glik; Figs. 4, 6, and 7 of Sun).
Regarding Claim 13, the combination of Glik and Sun would have rendered obvious a lens, comprising a substrate and a grating structure according to claim 1, wherein a surface of the base facing away from the grating portions attaches to a surface of the substrate (e.g., Fig. 2 and its description in Glik).
Regarding Claim 14, the combination of Glik and Sun would have rendered obvious a head mounted display, comprising an image source and the lens according to claim 13, wherein the lens is located on a light-emergent side of the image source (e.g., Figs. 1 and 2, paragraph [0018], of Glik).
Claims 9–12 are rejected under 35 U.S.C. 103 as being unpatentable over Glik and Sun, further in view of U.S. Patent Application Publication No. 2024/0230969 to Hansson.
Regarding Claim 9, the combination of Glik and Sun would have rendered obvious a processing method for the grating structure according to claim 1, comprises: providing a base, with a plurality of grating portions arranged at intervals along an extension direction of the base on one surface thereof; and coating an enhancement layer on a surface of each of the plurality of grating portions, with a uniform coating thickness (e.g., see Claim 1 above, Fig. 4 of Glik).
The combination of Glik and Sun does not explicitly disclose coating a photoresist on the enhancement layer; partially covering the photoresist with a mask, and sequentially performing an exposure and development on the photoresist to obtain a retained photoresist; changing the coating thickness of the enhancement layer not covered by the retained photoresist so that the enhancement layer for a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions.
Hansson teaches a method of etching to achieve different thicknesses or depths of etching in a grating structure, the method including (e.g., Figs. 1A–1F and their description) steps of coating a photoresist 16 on the layer to be etched; partially etching the photoresist to achieve a photoresist pattern with varied thicknesses; and etching with the modified photoresist pattern to achieve different depths or thicknesses of etching.
It would have been obvious to one of ordinary skill in the art at the time of effective filing to modify the device/method of Glik and Sun to include steps of coating a photoresist on the enhancement layer; partially covering the photoresist with a mask, and sequentially performing an exposure and development on the photoresist to obtain a retained photoresist; changing the coating thickness of the enhancement layer not covered by the retained photoresist so that the enhancement layer for a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions, as suggested by Hansson, as a suitable configuration for achieving the desired different thicknesses of Sun (e.g., MPEP §§ 2144.06–07).
Regarding Claim 10, the combination of Glik, Sun, and Hansson would have rendered obvious wherein the surface of each of the plurality of grating portions comprises a top portion parallel to the surface of the base and a side portion connecting the top portion to the surface of the base (e.g., Fig. 4 of Glik); the partially covering the photoresist with a mask, and sequentially performing an exposure and development on the photoresist to obtain a retained photoresist comprises: using the mask to cover the photoresist corresponding to the side portion and the surface of the base, or using the mask to cover the photoresist corresponding to the top portion; after performing the exposure and development, filling a groove space enclosed by the side portion and the surface of the base with the retained photoresist or locating the retained photoresist on a surface of the enhancement layer coated on the top portion; and, the changing the coating thickness of the enhancement layer not covered by the retained photoresist so that the enhancement layer for a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions comprises: increasing thickness of the enhancement layer coated on the top portion, or reducing thickness of the enhancement layer coated on the side portion, so that the enhancement layer on the top portion and side portion of one of the grating portions differs in thickness (e.g., Figs. 1A–1F of Hansson; also using known etching techniques that would yield predictable results, absent evidence of criticality or otherwise unobvious results from the claim features).
Regarding Claim 11, the combination of Glik, Sun, and Hansson would have rendered obvious wherein when filling a groove space enclosed by the side portion and the surface of the base with the retained photoresist, the changing the coating thickness of the enhancement layer not covered by the retained photoresist so that the enhancement layer for a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions comprises: controlling the retained photoresist to protrude from the groove space and be higher than thickness of the enhancement layer coated on the top portion; re-coating an enhancement layer through evaporation or magnetron sputtering on the top portion of at least one of the grating portions, wherein thickness of a re-coated enhancement layer is less than a height by which the retained photoresist protrudes from the groove space (e.g., paragraph [n0056] of Sun; also Figs. 1A–1F of Hansson; also using known etching techniques that would yield predictable results, absent evidence of criticality or otherwise unobvious results from the claim features).
Regarding Claim 12, the combination of Glik, Sun, and Hansson would have rendered obvious wherein when locating the retained photoresist on a surface of the enhancement layer coated on the top portion, changing the coating thickness of the enhancement layer not covered by the retained photoresist so that the enhancement layer for a first of the plurality of grating portions is different in thickness than the enhancement layer for a second of the plurality of grating portions comprises: in the arrangement direction of the plurality of grating portions, controlling width of the retained photoresist to be less than width of the enhancement layer coated on the top portion, and setting a width difference between the enhancement layer coated on the top portion and the retained photoresist as t; thinning thickness of the enhancement layer on the side portion of at least one of the grating portions, such that the thickness of the enhancement layer on the side portion is less than or equal to t (e.g., Figs. 1A–1F of Hansson; also using known etching techniques that would yield predictable results, absent evidence of criticality or otherwise unobvious results from the claim features).
Conclusion
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/RYAN CROCKETT/Primary Examiner, Art Unit 2871
1 Note that US 2025/0020928 to Liu et al. teaches similar features as Glik; and should Applicant traverse the teachings of Glik, the teachings of Liu should also be considered, and/or an appropriate statement made on the record disqualifying Liu as prior art if applicable.
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