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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 10/9/2025 has been entered.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 10/09/2025 is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Interpretation
Claim 30 recites condition (i) on an initial estimated arrangement of discrete volumes of the multitude and “n3(λ0) …. the bulk refractive indices of … a third optical medium”. Further, Claim 30 limits an intermediate optical element as having a substrate, a first optical medium, and a second optical medium though there is no inclusion of a third optical medium. The broadest reasonable interpretation of the claim extends to an arbitrary third optical medium and an arbitrary third bulk refractive index. As the third optical medium is not required to be related to the intermediate optical element, the breadth of the claim extends far beyond that described explicitly in the disclosure. Condition (i) provides a relationship between bulk indices of media in the intermediate optical element, fractional areas, and an arbitrary value n3(λ0-).
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.
Claims 30-31, 33-35, 37-38, and 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over “Anti-reflecting and photonic nanostructures” by Chattopadhyay et al. (hereinafter Chattopadhyay).
Regarding claim 30, Chattopadhyay discloses a method for making an optical element to modify a reflection of an optical signal having an operational wavelength λ0 (Section 2. Theory of anti-reflection), the method comprising: (A) specifying a design net power reflectivity of a transmissive layer (Equation (4) or (5)); (B) forming an intermediate optical element supported by a substrate, the intermediate optical element having an intermediate transmissive layer by spatially selectively processing a layer comprising a first optical medium to replace, in selected volumes of the layer, the first optical medium with the second optical medium, in accordance with an estimated arrangement of discrete volumes to form a contiguous multitude of the discrete volumes (Section 2.2.1 Rough Surface, 2.2.2 Porous Layers, 2.2.3 Moth eye, 2.2.4 Surface-relief grating, 2.2.6 Textured Surface and Section 3 Nanostructure in anti-reflection: fabrication and performance); (C) measuring an intermediate net power reflectivity of the intermediate transmissive layer of the intermediate optical element (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c); (D) altering the estimated arrangement of the discrete volumes of the multitude in accordance with a difference between the measured net power reflectivity and the specified design net power reflectivity (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c); and (E) forming at least one additional intermediate optical element by repeating steps (B) and (C) using the altered estimated arrangements of the discrete volumes of the multitude until the measured net power reflectivity of the at least one additional intermediate optical element is less than or about equal to the specified design net power reflectivity (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c),(F) wherein the optical element is the at least one additional intermediate optical element having the measured net power reflectivity that is less than or about equal to the specified design net power reflectivity (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c) ), for an initial estimated arrangement of the discrete volumes of the multitude: (i) f1[(n1(λ0) - n3(λ0))/(n1(λ0) + n3(λ0))] + f2[(n2(λ0) - n3(λ0))/ (n2(λ0) + n3(λ0))] ≈ f1[(nsub(λ0) – n1(λ0))/(nsub(λ0) + n1(λ0))] + f2[(nsub(λ0) – n2(λ0))/ (nsub(λ0) + n2(λ0))]
(ii) D~λo / [4(f1 x n1(λ0) + f2 x n2(λ0))], (iii) where f1 and f2 are fractional areas of the transmissive layer occupied by the first and second optical media, respectively, f1 + f2 ~ 1, wherein n1(λ0),n2(λ0), n3(λ0) and nsub are, respectively, the bulk refractive indices of the first optical medium, the second optical medium, a third optical medium and the substrate at the operational wavelength, and the transmissive layer has as substantially uniform thickness D (Fig. 2.6.6, 2.6.c, 2.8.a, 2.10.a, 2.12.a-e).
For a surface-corrugated structure, as disclosed in Chattopadhyay, n1 = nsub and n2 = n3. Under these conditions, condition (i) reduces to f1 ≈ f2. Given the further condition that f1 + f2 ≈ 1, the conditions on the fractional areas is that they are approximately 50%. In Chattopadhyay, there are various cross-sections of embodiments exhibiting approximately 50% values of the respective f1 and f2 fractional areas (see Fig. 2.8(a) and 2.9(a)) and various other geometries necessitating the fill factor (e.g. pyramidal structures ranging from a f1/f2 = 1 to f1/f2 = 0.
Thicknesses D in Chattopadhyay ranges in fractions of the operational wavelength (see Fig. 2.9(e) and 2.11 for example). In the Si pyramidal structures in air, the claimed numerical condition is met as D ~ λo / [4x(0/5 x 3.48 + 0.5 x 1)], where D is 50nm to 250nm and λo is 400nm to 800nm in the data shown.
Chattopadhyay discloses various critical features (i.e. geometry, material, etc.) of various intermediate optical elements that are iteratively tested to provide a reflectance characteristic. Further Chattopadhyay discloses “In order to optimize the ARG design, generally theoretical calculations are performed based on the rigorous coupled-wave analysis, first proposed by Moharam in 1981 [57]. This widely used analytical model is a relatively straightforward technique for obtaining the exact solution of Maxwell’s equations for the accurate analysis of the diffraction of electromagnetic waves by periodic structures” (Section 2.2.5). Further comparison of modeling and manufactured products is shown in, for example, Fig. 3.10.c.
Chattopadhyay generically discloses materials thusly: “for all practical purposes of optical AR, it is desirable to have a medium of low RI as close to 1.0 as possible. Few examples of such media are MgF2, CaF2 and SiO2 having n = 1.39, 1.44, 1.46 …a composite with a ‘material’ and ‘air’ as the two main components mixed in a definite ratio… a porous material ‘A’, say silicon (n = 3.8), will have a certain fraction (f) of silicon and (1 − f) fraction of air with n = 1.0. Effectively, porous silicon will have an RI in between 1.0 and 3.8 depending on the volume fraction ‘f’” and specifically discloses materials in Section 2.2 as a substrate mixed with air and Section 2.2.3 “the surface layer varies gradually from air to substrate”. It is unclear if each of the embodiments depicted in Figs. 2.8, 2.9, and 2.11 are necessarily surface structures on a substrate in air. As Chattopadhyay recognizes the use of the optical structures in air and a person having ordinary skill in the art would understand the ease and ubiquity of optical structure in a free-space (i.e. air environment), the claimed conditions met by the embodiments of Chattopadhyay in are would have been obvious.
Regarding claim 31, Chattopadhyay discloses calibrating an arrangement of the variously sized and distributed discrete volumes of the multitude (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c) so that the net power reflectivity exhibited by the transmission layer is less than or about equal to a design net power reflectivity that is in turn less than the power reflectivity that would be exhibited by an interface between a substrate and a third optical medium without the transmissive layer therebetween (Section 2.2.1 Rough Surface, 2.2.2 Porous Layers, 2.2.3 Moth eye, 2.2.4 Surface-relief grating, 2.2.6 Textured Surface and Section 3 Nanostructure in anti-reflection: fabrication and performance
Regarding claim 34, Chattopadhyay discloses performing step (B) multiple times to form a plurality of intermediate optical elements for multiple different estimated arrangements of the discrete volumes simultaneously on multiple corresponding distinct areas of a common substrate (Fig. 3.4.e, 3.4.f, 3.5.f, 3.6.e, 3.7.g, 3.9.b, 3.9.d, 3.9.f, 3.9.h, 3.10.c, 3.10.d, 3.12.c).
Regarding claim 35, Chattopadhyay discloses step (D) includes (i) altering the thickness D of the transmissive layer (Fig. 2.6.b-c, 2.8.c, 2.9.e), (ii) altering ft and f 2,where ft and f2 are fractional areas of the transmissive layer occupied by the first and second optical media, respectively, and fi + f2 1, or (iii) altering D, fi, and f2.
Regarding claim 37, Chattopadhyay discloses providing a third optical medium (air, e.g. Fig. 3.7 and 3.9.e,g) configured to be substantially transparent to the operational wavelength (e.g. λ0 = 1.5µm) and having a bulk refractive index at the operational wavelength of n3 (nair = 1); wherein the substrate is substantially transparent to the operational wavelength and has a bulk refractive index at the operational wavelength of nsub (nSi = 3.8) wherein the transmissive layer has a substantially uniform thickness D (Fig. 3.7 and 3.9.e,g), a first surface of the transmissive layer faces the substrate, a second surface of the transmissive layer is positioned against the third optical medium, whereby the transmissive layer is interposed between the substrate and the third optical medium (Fig. 3.7 and 3.9.e,g); wherein each discrete volume of the first optical medium is less than a first distance d1 in transverse extent in one or both transverse dimensions and is separated from at least one other discrete volume of the first optical medium by a transverse distance less than a second distance d2 through an intervening discrete volume of the second optical medium, and a relationship of the first and second distances d1 and d2 is defined as a sum of the first and second distances (d1 + d2) being less than a ratio of the operational wavelength to which the first, second, andthird optical media and the solid substrate are configured to be substantially transparent, relative to a sum of the bulk refractive indices at the operational wavelength for the solid substrate and the third optical medium (nsub(λ0) + n3(1)), whereby d1 + d2 <
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(d1+d2 ~ 200nm < λ0 / (1 = 3.8); Fig. 3.7 and 3.9.e,g) or (ii) each discrete volume of the second optical medium is less than a second distance d2 in transverse extent in one or both transverse dimensions and is separated from at least one other discrete volume of the second optical medium by a transverse distance less than a first distance d1 through an intervening discrete volume of the first optical medium, and a relationship of the first and second distances dl and d2 is defined as a sum of the first and second distances (d1 + d2) being less than a ratio of the operational wavelength
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to which the first, second, and third optical media and the solid substrate are configured to be substantially transparent, relative to a sum of the bulk refractive indices at the operational wavelength for the solid substrate and the third optical medium (nsub(Q) + n3
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), whereby d1 + d2 <
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the discrete volumes of the multitude are sized and distributed on the transmissive layer so that, for the optical signal within the operational wavelength λ0 and incident on the transmissive layer, the optical element exhibits (i) a first field amplitude reflectivity r1 from the first surface, (ii) a phase delay Δφ for single-pass propagation through the transmissive layer, and (iii) a second field amplitude reflectivity r2 from the second surface, each of which is substantially constant and non-zero, when averaged with a sampling area about equal in transverse extent to the operational wavelength a in both transverse dimensions, as a function of two-dimensional transverse position along the transmissive layer; and the substantially constant values of r1,Ap, and r2 result in a net power reflectivity of the transmissive layer that differs from a power reflectivity exhibited by an interface between the substrate and the third optical medium without the transmissive layer therebetween (Fig. 3.7 and 3.9).
Regarding claim 38, Chattopadhyay discloses propagating the optical signal to the optical element (e.g. Fig. 2.3).
Regarding claim 4, Chattopadhyay discloses over at least the operational wavelength range, nsub(λ0) ≠ n3(λ0) (e.g. index of silicon is not the same as the index of air, Fig. 2.11), and the substantially constant values of r1, Acp, and r2 result in net power reflectivity of the transmissive layer that is less than power reflectivity that would be exhibited by an interface between the substrate and the third optical medium without the transmissive layer therebetween (Fig. 2.11).
Regarding claim 5, Chattopadhyay discloses a net power reflectivity of the transmissive layer is less than about one fourth of the power reflectivity that would be exhibited by the interface between the substrate and the third optical medium without the transmissive layer therebetween (Fig. 2.11).
Regarding claim 6, Chattopadhyay discloses the optical element is structurally arranged so as to receive the optical signal at non-normal incidence or at substantially normal incidence (Section 2.2.1 Rough Surface, 2.2.2 Porous Layers, 2.2.3 Moth eye, 2.2.4 Surface-relief grating, 2.2.6 Textured Surface and Section 3 Nanostructure in anti-reflection: fabrication and performance).
Response to Arguments
Applicant's arguments filed 9/15/2025 have been fully considered but they are not persuasive.
On page 9 of the Remarks, Applicant arguments that the Chattopadhyay teachings do not address “the specific optimized (or starting) dimensions of discrete volumes to obtain the benefits … with respect to spatial averaging across multiple refractive indices”. Examiner respectfully disagrees as the lack of index modulation is presented in the “Basic Principles” section explaining vector method of AR design and implied in the single- and double-layer AR sections of design. In topographical design approaches, there is an optimization of discrete volumes for anti-reflection design. These approaches are described generically in Section 2.2 in terms of rough layers, porous layers, Moth eye structures, and surface-relief gratings in which discrete volumes vary refractive index in space. Specific embodiments of the discrete volumes are shown in Figs. 2,8, 2.9, and 2.11 at least.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CHRISTOPHER J STANFORD whose telephone number is (571)270-3337. The examiner can normally be reached 8AM-4PM PST M-F.
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/CHRISTOPHER STANFORD/Primary Examiner, Art Unit 2872