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 .
Drawings
The drawings with 39 Sheets of Fig. 1-20B received on 12/30/2024 are acknowledged and accepted.
Response to Amendment
The amendments to Claims 1,12,13,15,17,21,23, in the submission filed 12/30/2024 are acknowledged and accepted.
Cancellation of Claims 2,4-7,9,11,16,22,24,25,27,28,30, 36-99, is acknowledged and accepted.
Pending Claims are 1,3,8,10,12-15,17-21,23,26,29,31-35.
Claim Objections
Claim 19 objected to because of the following informalities:
Claim 19 recites “wherein the first of the substrate” in line 1. This appears to be a typo mistake. It is suggested to be replaced with –wherein the first side of the substrate--.
Appropriate correction is required.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim(s) 1,8,12,13,21, 32, is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Curtis et al (US 2018/0052320 A1).
Regarding Claim 1, Curtis teaches (fig 1, 20, 33A-D) an eyepiece (eyepiece 2000, para 293, fig 20) comprising:
a substrate (substrate 3302, para 349);
an input coupling grating (ICG 3320, para 353) on a first side of the substrate (substrate 3302); and
a morphed grating (combined OPE/EPE 3350, para 351), comprising characteristics of both a primary grating (first OPE grating 3351, second OPE grating 3352, para 351) and a secondary grating (EPE 3353, para 351) on at least the first side of the substrate (“the three sets of gratings may be superimposed onto each other”, para 351),
wherein the primary grating (first OPE grating 3351, second OPE grating 3352, para 351) has two or more layers with two or more associated pitches and orientation, the two or more associated pitches and orientation determine two or more wave vectors in momentum space (the two layers are first and second OPE gratings with associated pitches and orientations which determine the wave vectors respectively),
the secondary grating (EPE 3353, para 351) has a pitch and orientation that determines a wave vector in momentum space (the pitch and orientation of EPE determines the wave vector), and
the wave vector of the secondary grating (EPE 3353, para 351) is a linear combination of the two or more wave vectors of the primary grating (first and second OPE gratings 3351,3352) (as in fig 33C, wave vectors of first and second OPE gratings 3351, 3352 are along the sides of a right angled triangle and the wave vector of EP 3353 is along the third side of the triangle, this is indicated by the diamonds in fig 33C, which is a linear combination of the wave vectors of OPE 3351,3352)
Regarding Claim 8, Curtis teaches the eyepiece of claim 1,
wherein an index of refraction of the primary grating (first and second OPE gratings 3351,3352) is different from an index of refraction of the secondary grating (EPE 3353, para 351) (“different regions of diffractive element 3602 are characterized by differing indices of refraction resulting in modulated amplitude of light through diffractive element 3602”, para 591, fig 36A, “Although an example of diffractive element 3602 is an OPE, the variation in index of refraction can be utilized in additional diffractive elements making up an eyepiece, including the ICG and the EPE or other diffractive elements”, para 593).
Regarding Claim 12, Curtis teaches (fig 1, 20, 33A-D) an eyepiece (eyepiece 2000, para 293, fig 20) comprising:
a substrate (substrate 3302, para 349);
an input coupling grating (ICG 3320, para 353) on a first side of the substrate (substrate 3302); and
a morphed grating (combined OPE/EPE 3350, para 351), comprising characteristics of both a primary grating (first OPE grating 3351, second OPE grating 3352, para 351) and a secondary grating (EPE 3353, para 351) on at least the first side of the substrate (“the three sets of gratings may be superimposed onto each other”, para 351), wherein at least one of the primary and secondary gratings (first OPE grating 3351, second OPE grating 3352, para 351) is two-dimensional (first and second OPE gratings are superimpose and hence form a 2D gratings).
Regarding Claim 13, Curtis teaches the eyepiece of claim 12,
wherein a pitch of the secondary grating (EPE 3353, para 351) is different from a pitch of the primary grating (first OPE grating 3351, second OPE grating 3352, para 351) (as in fig 34A, the pitch of 3453 is larger than the pitch of gratings 3351 and 3352 which are equal).
Regarding Claim 21, Curtis teaches the eyepiece of claim 12,
wherein at least one of the primary (first OPE grating 3351, second OPE grating 3352, para 351) and secondary gratings (EPE 3353, para 351) was etched into the substrate (“the three sets of gratings are generated using an interference lithography technique on the substrate 3302. In some instances, the three sets of gratings are generated sequentially.” para 350).
Regarding Claim 32, Curtis teaches the eyepiece of claim 1,
wherein at least one of the primary and secondary gratings (“The patterned grating structure described herein may be used, for example, on an OPE and/or an EPE”, para 825, fig 121A) was imprinted over the substrate with nanoimprint lithography (imprint-based manufacturing, para 824, fig 120, “At step 12102A, a pattern is imprinted in the soluble layer”, para 827, “At step 12103A, etching is completed through and into the soluble layer. The imprinted cured polymer over the bottom sacrificial polymer layer etches at a different rate with a single etch chemistry”, para 128, fig 121A, “Various techniques may be used to mass produce a grating. For example, nano-imprint lithography may be used.”, para 503).
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.
Claim(s) 10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Curtis et al (US 2018/0052320 A1) in view of Singh et al (US 2021/072437 A1).
Regarding Claim 10, Curtis teaches the eyepiece of claim 1.
However, Curtis does not teach
wherein the secondary grating is either a recycler or antireflective grating.
Curtis and Singh are related as eyepieces with morphed gratings.
Singh teaches (fig 13C,17C),
wherein the grating (diffraction grating, para 1728, “further comprising a first layer disposed over said first diffraction grating”, para 1728, “further comprising a plurality of sublayers over said first layer, said plurality of sublayers comprising a first higher index material and a second lower index material”, para 1821) is either a recycler or antireflective grating (“wherein the plurality of sublayers over said first layer forms an anti-reflection (AR) coating.”, para 1830)
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the secondary grating of Curtis to include the anti-reflective grating of Singh for the purpose of blocking or reducing reflections (para 1819). (“wherein the plurality of sublayers over said first layer forms an anti-reflection (AR) coating.”, para 1830)
Claim(s) 14,15,17,18, 19,33, is/are rejected under 35 U.S.C. 103 as being unpatentable over Curtis et al (US 2018/0052320 A1).
Regarding Claim 14, Curtis teaches the eyepiece of claim 13.
However, Curtis does not teach
wherein the pitch of the secondary grating is less than the pitch of the primary grating.
However, 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). Curtis teaches that the pitch ratio is in a range of values. An increase in the secondary grating pitch will help in reducing artifacts while making the grating device bulky and a decrease in the pitch would make the grating les bulky while artifacts might increase. Therefore, the ratio between secondary and primary grating pitches is a result effective variable.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have the claimed pitch ratio, and one would have chosen the pitch of the secondary grating is less than the pitch of the primary grating according to a result effective variable balancing the need to improving image quality with device size. One would have been motivated to have pitches to be within the claimed range balancing a desired image quality with compact device size.
Regarding Claim 15, Curtis teaches the eyepiece of claim 12.
However, embodiment of fig 33A-D does not teach
wherein a line width of the secondary grating is different from a line width of the primary grating.
Embodiments of fig 33A-D and fig 36 A are related as eyepieces.
Embodiment of fig 36A of Curtis teaches
wherein a line width of the secondary grating (EPE 3603, para 591) is different from a line width of the primary grating (primary grating made of gratings 3605 and 3605 which are considered as two gratings, para 591) (line width of 3603 is different from line width of regions 3605 and 3606, fig 33A, “width W of regions 3605 and 3606 can be on the order of 0.5 mm-5 mm, whereas the pitch of grating elements 3603 can be on the order of 300 nm to 1500 nm”, para 595).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the morphed grating of embodiment of fig 33A-D of Curtis to include the line widths of embodiment of fig 42A of Curtis for the purpose of a versatile design for eyepieces which results in spreading of light (“This dithering of the index of refraction facilitates spreading of the light as it is coupled out of the diffractive structure, thereby controllably forming a virtual image with increased coherence”, para 590).
Regarding Claim 17, Curtis teaches the eyepiece of claim 12, the morphed grating has a two-sided configuration (“the three sets of gratings in the combined OPE/EPE region 3450 (a first OPE grating 3451, a second OPE grating 3452, and an EPE grating 3453) are distributed between the two sides of the substrate 3402”, para 356).
However, embodiment of fig 33A-D of Curtis does not teach
wherein the primary grating includes a portion on a second side of the substrate opposite the first side of the substrate.
Embodiments of fig 33A-D and fig 42 A are related as eyepieces.
Embodiment of fig 42A of Curtis teaches
wherein the primary grating (grating 4225A, para 395, 396) includes a portion on a second side of the substrate opposite the first side of the substrate (as in fig 42A, grating 4225A).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the morphed grating of embodiment of fig 33A-D of Curtis to include the grating of embodiment of fig 42A of Curtis for the purpose of a versatile design with changing periodic structures for phase variation (para 395).
Regarding Claim 18, Curtis teaches the eyepiece of claim 17,
wherein the first side (first side corresponding to presence of OPE and EPE regions, fig 20) of the substrate (substrate 2000, fig 20) is proximal to a user, and the second side (second side opposite to first side of substrate 2000) of the substrate is distal the user.
Regarding Claim 19, Curtis teaches the eyepiece of claim 17,
wherein the first side (first side corresponding to presence of OPE and EPE regions, fig 20) of the substrate (substrate 2000, fig 20) is distal to a user, and the second side (second side opposite to first side of substrate 2000) of the substrate is proximal the user (a rotation of the eyepiece device would result in such a configuration).
Regarding Claim 33, Curtis teaches the eyepiece of claim 32,
wherein the eyepiece comprises a resist layer thickness of less than 50 nanometers (“the thickness of the stop etch layer is between 2 nm and 40 nm”.
However, Curtis does not teach
a resist layer thickness of less than 50 nanometers.
However, 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). The resist layer thickness can be in a range of values. An increase in resist thickness results in deeper etch possibility but makes the etching might get harder. A decrease in resist thickness results in shallower easier etching but might make etching into the next layer. Therefore, the resist thickness is a result effective variable.
One would have chosen the resist thickness to be less than 50nm according to a result effective variable balancing the need to improving etching coverage with precision.
Therefore, it would have been obvious to an ordinarily skilled artisan before the effective filing date of the claimed invention to optimize the resist thickness. One would have been motivated to have the resist thickness to be less than 50nm to have an optimal thickness balancing a desired effectiveness of etch and desired precision.
Claim(s) 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Curtis et al (US 2018/0052320 A1) in view of Chi et al (WO 2021/041333 A1).
Regarding Claim 20, Curtis teaches the eyepiece of claim 1.
However, Curtis does not teach
further comprising an anti-reflective grating on a second side of the substrate opposite the first side of the substrate.
Curtis and Chi are related as eyepieces with gratings.
Chi teaches (fig 38),
further comprising an anti-reflective grating (grating coupler 3820 with anti-reflective layer 3850, para 222) on a second side (bottom side) of the substrate (substrate 3810) opposite the first side (first side is the top side) of the substrate.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the eyepiece of Curtis to include the anti-reflective grating of Chi for the purpose of reducing the reflection of the external light at bottom surface (para 222).
Claim(s) 23,26,31, is/are rejected under 35 U.S.C. 103 as being unpatentable over Curtis et al (US 2018/0052320 A1) in view of Yang et al (US 2020/0158942 A1).
Regarding Claim 23, Curtis teaches (fig 1, 20, 33A-D) an eyepiece (eyepiece 2000, para 293, fig 20) comprising:
a substrate (substrate 3302, para 349);
an input coupling grating (ICG 3320, para 353) on a first side of the substrate (substrate 3302); and
a morphed grating (combined OPE/EPE 3350, para 351), comprising characteristics of both a primary grating (first OPE grating 3351, second OPE grating 3352, para 351) and a secondary grating (EPE 3353, para 351) on at least the first side of the substrate (“the three sets of gratings may be superimposed onto each other”, para 351),
wherein at least one of the primary and secondary gratings was etched (“the three sets of gratings are generated using an interference lithography technique on the substrate 3302. In some instances, the three sets of gratings are generated sequentially.” para 350) into a coating (coating is the photoresist used in lithography) over the substrate (substrate 3302, para 349).
However, Curtis does not teach
wherein the coating is partially on at least one of the primary and secondary gratings.
Curtis and Yang are related as morphed gratings.
Yang teaches (fig 6,7),
wherein the coating (substance 716, para 36) is partially on at least one of the primary and secondary gratings (pattern 710, para 36).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the eyepiece of Curtis to include the coating partially on at least one of the primary and secondary gratings of Yang for the purpose of using techniques for simplifying complex optical devices (para 3, lines 1-4).
Regarding Claim 26, Curtis-Yang teaches the eyepiece of claim 23.
However, Curtis does not teach
wherein the coating at least partially fills trench
Curtis and Yang are related as morphed gratings.
Yang teaches (fig 6,7),
wherein the coating (substance 716, para 36) at least partially fills trench (trenches of pattern 710, para 36).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the eyepiece of Curtis to include the coating partially filling trenches of Yang for the purpose of using techniques for simplifying complex optical devices (para 3, lines 1-4).
Regarding Claim 31, Curtis-Yang teaches the eyepiece of claim 26,
wherein etching of at least one of the primary and secondary gratings (“the three sets of gratings are generated using an interference lithography technique on the substrate 3302. In some instances, the three sets of gratings are generated sequentially.” para 350, Curtis) is on a side of the substrate proximal to a user, a side of the substrate distal to a user, or both (gratings are placed or etched as one sided as in fig 33D or two sided as in fig 34B).
Claim(s) 34,35, is/are rejected under 35 U.S.C. 103 as being unpatentable over Curtis et al (US 2018/0052320 A1) in view of Singh et al (WO 2020/0185954, hereafter Singh ‘954).
Regarding Claim 34, Curtis teaches the eyepiece of claim 32.
However, Curtis does not teach
wherein at least one of the primary and secondary gratings comprises an imprinted polymer consisting of a non-filler-based polymer with an index of refraction less than 1.8.
Curtis and Singh’954 are related as gratings in eyepieces.
Singh’954 teaches (fig 17A,B),
wherein at least one of the primary and secondary gratings comprises an imprinted polymer consisting of a non-filler-based polymer with an index of refraction less than 1.8 (“The patterned layer having a refractive index less than about 1.8 can be obtained by depositing (e.g., using jet deposition technology) a patternable material (e.g., polymer or resist) having a refractive index less than about 1.8 over a substrate (e.g., a substrate comprising a material with refractive index greater than or equal to about 1.8). The deposited patternable material can subsequently be patterned, for example, with contact imprint lithography”, para 811).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the eyepiece of Curtis to include the imprinted polymer consisting of a non-filler-based polymer of Singh’954 for the purpose of using versatile techniques for features with uniform height, depth and/or pitch or features with different heights, depths and/or pitch (para 812).
Regarding Claim 35, Curtis teaches eyepiece of claim 32.
However, Curtis does not teach
wherein at least one of the primary and secondary gratings comprises an imprinted polymer consisting of a filler-based polymer with an index of refraction in a range from 1.8 to 2.1.
Curtis and Singh’954 are related as gratings in eyepieces.
Singh’954 teaches (fig 10),
wherein at least one of the primary and secondary gratings comprises an imprinted polymer consisting of a filler-based polymer with an index of refraction in a range from 1.8 to 2.1 (“A shows an example method of patterning a waveguide 1001 comprising a material with a high refractive index (e.g., refractive index greater than or equal to about 1.8)”, “The uncured patternable layer 1011 can be patterned using an imprint template 1007”, para 769).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the eyepiece of Curtis to include the imprinted polymer consisting of a filler-based polymer of Singh’954 for the purpose of using versatile techniques to allow fabrication of diffractive features with varying heights and/or pitch (para 769).
Allowable Subject Matter
Claim 3 objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim 3 is allowable for at least the reason:
“wherein a pitch of the secondary grating is less than any pitch of the primary grating by a factor of at least two times an index of refraction of the substrate.”
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Popovich et al (US 2024/0012247 A1) teaches an eyepiece with a substrate and overlapping gratings.
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/JYOTSNA V DABBI/Primary Examiner, Art Unit 2872 10/10/2026
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