`DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 February 5, 2026 has been entered. Claims 1-6, 9-13, and 15-23 are under consideration.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-6, 9-13, and 15-23 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
The original disclosure does not contain any description regarding the relationship between a second refractive index and a third refractive index as currently claimed. The Remarks filed on February 5, 2026 referenced support for the amendments can be found in at least Paras [0023], [0031], and Fig. 2B. Para [0023] discusses the device angle ϑ, Para [0031] discusses the refractive index of the device portion (216A) having a first refractive index and the impedance matching portion (216B) having a second refractive index, and material for a hard mask layer. However, there is no discussion of “a third refractive index” that corresponds with an “anti-reflective material”. The examiner finds a reference to a “third” refractive index N3 in Para [0033], but this refractive index is the “refractive index of air (or another medium surrounding the waveguide 100)” The second impedance matching formula does not sufficiently describe “the third refractive index of about 1.4 to about 2.0” in the terms as recited in the independent claims. N1 is the refractive index of the device portion, Nsubstrate is the refractive index of the substrate, and Nanti-reflective is the refractive index of the anti-reflective portion. There is no disclosure of the refractive index of the impedance matching portion in the second impedance matching formula that includes the anti-reflective material and an impedance matching portion. Fig. 2B does not have any refractive index values labeled.
For these reasons, the examiner determined the amendment—an anti-reflective material disposed on a second side of the optical device substrate opposite the first side of the optical device substrate, the anti-reflective material having a third refractive index of about 1.4 to about 2.0, where the third refractive index is different from the second refractive index—to be new matter.
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, 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 1-6, 9-13, and 15-23 are rejected under 35 U.S.C. 103 as being unpatentable over Godet et al. (US 2020/0194217 A1, herein “Godet”) in view of Greiner et al. (US 2012/0275746 A1, herein “Greiner”).
Regarding claim 1 Godet discloses an augmented reality waveguide (Para [0024]) comprising:
an optical device substrate (100 in Fig. 1) of the augmented reality waveguide; and
at least one output coupling grating (112) grating disposed on a first side the optical device substrate (100), the at least one output coupling grating (112) having a plurality of device structures (fins of slant angle gratings), of the plurality of device structures defining a gap therebetween (slant angle gratings or surface relief gratings). Godet further discloses a device portion (output coupling region 106) disposed on the optical device substrate 100, Figs. 1-2, and 4A-4C.
However, Godet does not explicitly disclose a device portion, the device portion including a device material having a first refractive index of about 1.9 to about 4.0; and an impedance matching portion disposed over the device portion, the impedance matching portion having a second refractive index of about 1.4 to about 2.0. Godet further does not teach an anti-reflective material disposed on a second side of the optical device substrate opposite the first side of the optical device substrate, the anti-reflective material having a third refractive index of about 1.4 to about 2.0 where the third refractive index is different from the second refractive index.
Greiner teaches highly efficient optical gratings with reduced thickness requirements and impedance matching layers. The gratings (corresponds with “the device portion”) including a device material having a first refractive index of about 1.9 to about 4.0 (n = 2.2, Para [0068]); and an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the chosen refractive index is to recreate an alternating high and low electric field nodes, which translates to the phase velocities of fast and slow modes of the grating layer. This techniques improves the grating efficiency (Para [0047]-[0048]). Greiner further teaches impedance matching layer (1202) an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the impedance matching layer further improves grating efficiency by reducing the reflection of the optical signal transmitted through the grating layer (Abstract).
The embodiment shown in Fig. 9 has a first impedance matching layer (903) provided on the first surface of the grating layer (901) and a second impedance matching layer (905) provided on the second surface of the grating layer (901).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to recognize the highly efficient optical gratings as described in Greiner’s invention would have been modifiable to the Godet’s invention since Greiner’s grating is capable of being formed on a thin substrate such as an augmented reality waveguide (“lens”). One would be motivated to adopt the grating characteristics and impedance matching layers in Greiner’s waveguide for increasing grating efficiency (Figs. 4D, 4E, and 4F). The impedance matching grating structures with antireflective coatings improve augmented head-up displays by maximizing light transmission efficiency, enhancing image brightness, and reducing unwanted internal reflections (AKA ghost images).
Claim 2. Godet in view of Greiner teach the duty cycle of the waveguide is between about 5% and about 95% (Greiner: duty cycle of 54%, Para [0054]).
Claim 3. Godet in view of Greiner teach a thick layer (1201) has a refractive index n=2.2 and an impedance matching layer (1202) having a refractive index of 1.444. The refractive index difference is 0.756, which is with the range of 0.45 and 1.15 (Para [0068]).
Claim 4. Godet in view of Greiner teach the plurality of device structures (fins) are formed at a device angle ϑ defined by the substrate and a sidewall of each device structure of the plurality of device structures, wherein the device angle ϑ is an acute angle (Godet: Figs. 2 and 4A-4C, Para [0042], [0047], and [0052]).
Claim 5. Godet in view of Greiner teach the device material includes materials containing germanium, silicon, titanium oxide, niobium oxide, silicon nitride, hafnium oxide, tantalum oxide, scandium oxide, or combinations thereof (Figs. 14 and 21, Para [0071], [0075]).
Claim 6. Godet in view of Greiner teach the impedance matching portion includes impedance matching materials containing silicon nitride, silicon oxide, aluminum oxide, or combinations thereof (Figs. 14 and 21, Para [0071], [0075]).
Claim 9. Godet in view of Greiner teach the invention of claim 1, but do not explicitly teach the impedance matching formula is: N2 ≈ (N1 x N3)0.5, wherein N2 is the second refractive index, N1 is the first refractive index, and N3 is the refractive index of air or a surrounding medium.
However, Greiner teaches the general condition for optimizing the impedance matching layers for one or the other polarization states. Optimizing the impedance matching layer can be modifying the index and thickness for an impedance matching layer to minimize reflection of one polarization state (Para [0064]). Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to optimize the refractive indices of the impedance matching layer, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art, In re Aller, 105 USPQ 233 (C.C.P.A. 1955).
Regarding claim 10, Godet discloses an augmented reality waveguide (Para [0024]) comprising:
an optical device substrate (100 in Fig. 1) of the augmented reality waveguide; and
at least one output coupling grating (112) grating disposed over the optical device substrate (100), the at least one output coupling grating (112) having a plurality of device structures, (fins of slant angle gratings) of the plurality of device structures defining a gap therebetween (slant angle gratings or surface relief gratings). Godet further discloses a device portion (output coupling region 106) disposed on the optical device substrate 100, Figs. 1-2, and 4A-4C. Furthermore, Godet discloses the device portion (fins) having a first sidewall and a second sidewall that are both oriented at the same acute angle (Para [0042], [0047], and [0052]) relative to a surface of the optical device substrate (Fig. 2).
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However, Godet does not explicitly disclose a device portion including a device material having a first refractive index of about 1.9 to about 4.0; and an impedance matching portion disposed over the device portion, the impedance matching portion having a second refractive index of about 1.4 to about 2.0, wherein a difference between the first refractive index and second refractive index is about 0.45 to about 1.15. Godet further does not teach an anti-reflective material disposed on a second side of the optical device substrate opposite the first side of the optical device substrate, the anti-reflective material having a third refractive index of about 1.4 to about 2.0 where the third refractive index is different from the second refractive index.
Greiner teaches highly efficient optical gratings with reduced thickness requirements and impedance matching layers. The gratings (corresponds with “the device portion”) including a device material having a first refractive index of about 1.9 to about 4.0 (n = 2.2, Para [0068]); and an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the chosen refractive index is to recreate an alternating high and low electric field nodes, which translates to the phase velocities of fast and slow modes of the grating layer. This techniques improves the grating efficiency (Para [0047]-[0048]). Greiner further teaches impedance matching layer (1202) an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the impedance matching layer further improves grating efficiency by reducing the reflection of the optical signal transmitted through the grating layer (Abstract).
The embodiment shown in Fig. 9 has a first impedance matching layer (903) provided on the first surface of the grating layer (901) and a second impedance matching layer (905) provided on the second surface of the grating layer (901).
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It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to recognize the highly efficient optical gratings as described in Greiner’s invention would have been modifiable to the Godet’s invention since Greiner’s grating is capable of being formed on a thin substrate such as an augmented reality waveguide (“lens”). One would be motivated to adopt the grating characteristics and impedance matching layers in Greiner’s waveguide for increasing grating efficiency (Figs. 4D, 4E, and 4F). The impedance matching grating structures with antireflective coatings improve augmented head-up displays by maximizing light transmission efficiency, enhancing image brightness, and reducing unwanted internal reflections (AKA ghost images).
Claim 11, Godet in view of Greiner teach the plurality of device structures are discrete optical device structures (Greiner: Figs. 12-13B and Para [0042]).
Claims 12-13. Godet in view of Greiner teach a waveguide combiner (Godet Fig. 1) includes an input coupling grating region (102) (a first region) defined by a plurality of fins (108), an intermediate grating region (104) (a second region) defined by a plurality of fins (110), and an output coupling grating region (106) (a third region) defined by a plurality of fins (112). See Fig. 2 for details of the “fins”.
Claim 15. Godet in view of Greiner teach the anti-reflective material is a silicon nitride, a silicon oxide, an aluminum oxide or a combinations thereof (Greiner: Para [0075]).
Claim 16. Godet in view of Greiner teach the invention of claim 10, but do not explicitly teach the impedance matching formula is: N2 ≈ (N1 x N3)0.5, wherein N2 is the second refractive index, N1 is the first refractive index, and N3 is the refractive index of air or a surrounding medium.
However, Greiner teaches the general condition for optimizing the impedance matching layers for one or the other polarization states. Optimizing the impedance matching layer can be modifying the index and thickness for an impedance matching layer to minimize reflection of one polarization state (Para [0064]). Therefore, it would have been obvious to one having ordinary skill in the art to one of ordinary skill in the art at the time of filing was made to optimize the refractive indices of the impedance matching layer, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art, In re Aller, 105 USPQ 233 (C.C.P.A. 1955).
Claim 17. Godet in view of Greiner teach the plurality of device structures are disposed with a device angle α is about 78°-90° (Greiner: Para [0069]).
Claim 18. Godet discloses a method comprising: disposing two or more layers of material (substrate 210, grating material 212, etch stop layer 211, patterned hardmask 213) on a first side surface of a substrate (210) of the augmented reality waveguide; and
etching through the two or more layers of material (hardmask 213 and grating material 212, Para [0031]) to form and augmented reality waveguide comprising: a plurality of device structures (fins) forming at least one output coupling (106) having two or more portions, wherein the two or more portions include:
a device portion (output region 106) disposed on the optical device substrate 100, Figs. 1-2, and 4A-4C.
However, Godet does not explicitly disclose a device portion having a first refractive index of about 1.9 to about 4.0; and an impedance matching portion disposed on the device portion, the impedance matching portion having a second refractive index of about 1.4 to about 2.0, wherein a difference between the first refractive index and second refractive index is about 0.45 to about 1.15. Godet further does not teach an anti-reflective material disposed on a second side of the optical device substrate opposite the first side of the optical device substrate, the anti-reflective material having a third refractive index of about 1.4 to about 2.0 where the third refractive index is different from the second refractive index.
Greiner teaches highly efficient optical gratings with reduced thickness requirements and impedance matching layers. The gratings (corresponds with “the device portion”) including a device material having a first refractive index of about 1.9 to about 4.0 (n = 2.2, Para [0068]); and an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the chosen refractive index is to recreate an alternating high and low electric field nodes, which translates to the phase velocities of fast and slow modes of the grating layer. This techniques improves the grating efficiency (Para [0047]-[0048]). Greiner further teaches impedance matching layer (1202) an impedance matching portion (1202) disposed over the device portion (gratings), the impedance matching portion having a second refractive index of about 1.4 to about 2.0 (n=1.444, Para [0068]). Greiner teaches the impedance matching layer further improves grating efficiency by reducing the reflection of the optical signal transmitted through the grating layer (Abstract).
The embodiment shown in Fig. 9 has a first impedance matching layer (903) provided on the first surface of the grating layer (901) and a second impedance matching layer (905) provided on the second surface of the grating layer (901).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to recognize the highly efficient optical gratings as described in Greiner’s invention would have been modifiable to the Godet’s invention since Greiner’s grating is capable of being formed on a thin substrate such as an augmented reality waveguide (“lens”). One would be motivated to adopt the grating characteristics and impedance matching layers in Greiner’s waveguide for increasing grating efficiency (Figs. 4D, 4E, and 4F). The impedance matching grating structures with antireflective coatings improve augmented head-up displays by maximizing light transmission efficiency, enhancing image brightness, and reducing unwanted internal reflections (AKA ghost images).
Claim 19-20. Godet in view of Greiner teach the two or more layers of material are disposed with PVD process or a CVD process and the plurality of device structures are formed with ion-beam or electron beam etching (Godet: Figs. 6 and 8-9).
Claim 21 and 23. Godet in view of Greiner teach gratings can have various designs, shapes, spacing, density, etc. (Para [0062]). Since the duty cycle of the grating is determined by dividing the linewidths by the pitches, then varying shapes and spacing would necessarily have varying duty cycle.
Claim 22. Godet in view of Greiner teach the duty cycle of the waveguide is between about 5% and about 95% (Greiner: duty cycle of 54%, Para [0054]).
Response to Arguments
Applicant's arguments filed 1-6, 9-13, and 15-23 have been fully considered but they are not persuasive.
The amended limitations to independent claims 1, 10, and 18 are addressed. Godet in view of Greiner teaches implementing anti-reflective layer(s) as impedance matching layer(s) wherein the first and second impedance matching layers have the same thickness and refractive index to remove the oscillations in the diffraction efficiency, thus increasing grating efficiency.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Erin D Chiem whose telephone number is (571)272-3102. The examiner can normally be reached 10 am - 6 pm.
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/ERIN D CHIEM/Examiner, Art Unit 2874
/THOMAS A HOLLWEG/Supervisory Patent Examiner, Art Unit 2874