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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The prior art documents submitted by applicant in the Information Disclosure Statements filed on August 16, 2024, August 22, 2024, and November 5, 2024 have all been considered and made of record (note the attached copies of form PTO-1449).
Drawings
Six (6) sheets of drawings were filed on July 26, 2024 and have been considered by the examiner.
Specification
Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
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.
Claim(s) 1-17 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Keech et al. (US 2019/0114484 A1), hereafter Keech, in view of Masuda (US 2018/0329208 A1).
Regarding Claim 1; Keech teaches (see Figures 1 and 2) a composite lightguide (10; Paragraph [0035]), comprising:
a support substrate (20; Paragraph [0035]) comprising a surface (22; Paragraph [0035]); and
a lightguide layer disposed on the surface of the support substrate (waveguide layer 40; Paragraph [0038]),
the lightguide layer comprising an entrance grating (30A; Paragraph [0036]) and an exit grating (30B; Paragraph [0036]),
the lightguide layer having a refractive index nd greater than 1.60 (the waveguide layer refractive index nG≥2, Paragraph [0043]);
wherein a ratio of a density of the lightguide layer to a density of the support substrate is greater than 1.40 (Keech teaches a waveguide layer made of TiO2 (Paragraph [0043]), which has a density of 4.23 g/cm3 and a support substrate made of fused silica (Paragraph [0042]), which has a density of 2.20 g/cm3 (since the materials of the lightguide layer and the support substrate are the same as applicant’s materials (specification, Paragraph [0037], Table 1, and [0041] , they would have the same known material properties, including density and index of refraction. Therefore, the ratio of a density of the lightguide layer to a density of the support substrate taught by Keech is 1.92).
Keech further teaches a lightguide layer (waveguide layer 40) thickness in the range of 1µm-100µm (Paragraph [0008]), but does not specifically disclose a thickness of the support substrate (20) or a ratio of a thickness of the lightguide layer to a thickness of the support substrate of less than 0.50. However, in the same field of endeavor, Masuda teaches that the thickness of the substrate (Figure 2A, element 34A; Paragraph [0073]) falls in the range of 0.5mm-2.0mm (Paragraph [0073]). Therefore, using even the maximum thickness of Keech’s lightguide layer (0.1mm) in combination with the minimum thickness of the support substrate thickness taught by Masuda (0.5mm) yields a ratio of a thickness of the lightguide layer to a thickness of the support substrate of 0.20, which is less than 0.50. It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to modify the thickness of Keech’s support substrate to have the thickness as taught by Masuda to provide sufficient support for a lightguide in a head mounted display and one of ordinary skill could have combined the elements by known coupling methods with no change in their respective functions to yield predictable results. KSR International Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
Regarding claim 2; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the ratio of the density of the lightguide layer to the density of the support substrate is greater than 1.70 (Keech teaches a density of the lightguide layer 40 is made of TiO2 (Paragraph [0043]), which has a density of 4.23 g/cm3 and support substrate 20 is made of fused silica (Paragraph [0042]), which has a density of 2.20 g/cm3. Therefore, the ratio of a density of the lightguide layer to a density of the support substrate is 1.92).
Regarding claims 3-4; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein a ratio of a density of the composite lightguide to the density of the lightguide layer is less than 0.80, or 0.60 (Keech teaches a composite lightguide with a lightguide layer made of TiO2 (Paragraph [0043]), which has a density of 4.23 g/cm3 and a support substrate made of fused silica (Paragraph [0042]), which has a density of 2.2 g/cm3. Keech further teaches a lightguide layer thickness in the range of 1µm-100µm (Paragraph [0008]). Masuda teaches a thickness of the support substrate of 0.5mm-2.0mm (Paragraph [0073]). Choosing values in the center of each thickness range (0.05mm lightguide layer and 1mm support substrate) and using the materials taught by Keech (TiO2 lightguide layer with a density of 4.23 g/cm3 and fused silica support substrate with a density of 2.2 g/cm3) yields a density of the composite lightguide of 2.30 g/cm3. Therefore, Keech and Masuda teach a ratio of the density of the composite lightguide (2.30 g/cm3) to the density of the lightguide layer (4.23 g/cm3) of 0.54).
Regarding claims 5-6; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the density of the lightguide layer is greater than 3.5 g/cm3, or 5.0 g/cm3 (Keech teaches example material Ta2O5 (Paragraph [0043]), which has a density of 8.18 g/cm3 (Ta2O5 is included in applicant’s specification (Paragraph [0037] and Table 1) and has the same known material properties, including density and index of refraction)).
Regarding claims 7-8; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the density of the support substrate is less than 3.0 g/cm3, or 2.6 g/cm3 (Keech teaches example material fused silica (Paragraph [0042]), which has a density of 2.2 g/cm3).
Regarding claim 9; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the ratio of the thickness of the lightguide layer to the thickness of the support substrate is less than 0.30 (Keech teaches a lightguide layer thickness in the range of 1µm-100µm (Paragraph [0008]). Masuda teaches a thickness of the support substrate of 0.5mm-2.0mm (Paragraph [0073]). Therefore, using even the maximum lightguide layer thickness taught by Keech (0.1mm) in combination with the minimum support substrate thickness taught by Masuda (0.5mm) yields a ratio of a thickness of the lightguide layer to a thickness of the support substrate of 0.2).
Regarding claims 10-11; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the thickness of the lightguide layer is less than 0.20 mm, or 0.10 mm (Keech teaches a lightguide layer thickness in the range of 1µm-100µm (Paragraph [0008])).
Regarding claims 12-13; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the thickness of the support substrate is greater than 0.30 mm, or 0.50 mm (Masuda teaches a thickness of the support substrate of 0.5mm-2.0mm (Paragraph [0073])).
Regarding claims 14-15; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the lightguide layer has a refractive index nd greater than 1.8, or 2.0 (Keech teaches a lightguide layer refractive index nG≥2 (Paragraph [0043])).
Regarding claim 16; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the support substrate has a refractive index nd less than 1.50 (Keech teaches a support substrate refractive index nS≤1.5 (Paragraph [0042])).
Regarding claim 17; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the lightguide layer comprises glass, the glass comprising one or more of TiO2, Nb2O5, WO3, La2O3, and Bi2O3 (Keech teaches example lightguide layers comprising TiO2 (Paragraph [0043]), and Nb2O5 (Paragraph [0051])).
Regarding claims 19-20; Keech and Masuda teach the composite lightguide of claim 1. Keech and Masuda further teach a composite lightguide wherein the refractive index nd of the lightguide layer is greater than 1.80 (Keech teaches a lightguide layer refractive index nG≥2 (Paragraph [0043])) and the composite lightguide has a density less than 4.0 g/cm3, or 3.6 g/cm3 (Keech teaches a composite lightguide with a lightguide layer made of TiO2 (Paragraph [0043]), which has a density of 4.23 g/cm3 and a support substrate made of fused silica (Paragraph [0042]), which has a density of 2.2 g/cm3. Keech further teaches a lightguide layer thickness in the range of 1µm-100µm (Paragraph [0008]). Masuda teaches a thickness of the support substrate of 0.5mm-2.0mm (Paragraph [0073]). Choosing values in the center of each thickness range (0.05mm lightguide layer and 1mm support substrate) and using the materials taught by Keech (TiO2 lightguide layer with a density of 4.23 g/cm3 and fused silica support substrate with a density of 2.2 g/cm3) yields a density of the composite lightguide of 2.30 g/cm3).
Claim 18 is rejected under 35 U.S.C. 103 as being unpatentable over Keech in view of Masuda as applied to claim 1 above, and in further view of Ritter et al. (US 2023/0105927 A1), hereafter Ritter.
Regarding claim 18; Keech and Masuda teach the composite lightguide of claim 1, wherein the lightguide comprises glass, the glass comprising one or more of TiO2, Nb2O5, WO3, La2O3, and Bi2O3 (Keech teaches example lightguide layers comprising TiO2 (Paragraph [0043]), and Nb2O5 (Paragraph [0051])). Keech and Masuda do not teach a composite lightguide wherein the glass further comprises P2O5. However, in the same field of endeavor, Ritter teaches a light guide plate (title), with the optical glass including Nb2O5 and P2O5 (Ritter, abstract). Thus, one of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious use a material with the desired properties (such as P2O5) known to form waveguides in display devices for its high transparency , and since P2O5 was a known alternative to form waveguides in display devices and one of ordinary skill in the art could have combined the elements by known coupling methods with no change in their respective functions to yield predictable results. KSR International Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Richards et al. (US 2015/0277116 A1) teaches a lightguide with in-coupling and out-coupling regions for a head wearable display (see Figures 1-2).
Lowney (US 2023/0236424 A1) teaches a lightguide with an “incoupler” and an “outcoupler” (see Figure 2) with embodiments in a head-mounted display (see Figure 1).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PETER L KAULFUSS whose telephone number is (571)270-7260. The examiner can normally be reached Monday-Friday, 9 AM to 5 PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Uyen-Chau Le can be reached at (571)272-2397. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/P.L.K./Examiner, Art Unit 2874
/UYEN CHAU N LE/Supervisory Patent Examiner, Art Unit 2874
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