/PRIYANK J SHAH/Primary Examiner, Art Unit 2626 DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
2. 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.
3. Claim(s) 1 and 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa at el. (US 2021/0055603 A1, hereinafter referred as “Kurokawa”) in view of Li et al. (US 2020/0218011 A1, hereinafter referred as “Li”).
Regarding claim 1, Kurokawa discloses a display device (title and abstract disclose display device) comprising:
a first transparent substrate (Fig. 4 and ¶0046 discloses first substrate SUB1 comprises a transparent substrate 10);
a second transparent substrate which has a first surface and a second surface different from the first surface (Fig. 4 and ¶0046 disclose second substrate SUB2 comprises a transparent substrate 20 which necessarily presents distinct main/end surfaces);
a liquid crystal layer which is located between the first transparent substrate and the second transparent substrate and contains a polymer dispersed liquid crystal (¶0044 and ¶0047 disclose the display panel PNL comprises a polymer dispersed liquid crystal layer 30 held between the first substrate SUB1 and the second substrate SUB2);
at least one light emitting unit configured to emit illumination light for illuminating the liquid crystal layer (Figs. 2-3, ¶0043 and ¶0045 disclose LS emits into end E22 and the light propagates through the display panel).
Kurakawa doesn’t disclose a diffractive optical element which faces the first surface, is provided at a position which does not overlap the liquid crystal layer, and is configured to diffract the illumination light.
However, in the same field of endeavor, Li discloses a diffractive optical element which faces the first surface (Fig. 3A and ¶0080 disclose diffractive grating 132 of the grating coupler 130 may include grooves, ridges or similar diffractive features of a diffraction grating formed or otherwise provided on or in the surface 112, 114 of the light guide 110), is provided at a position which does not overlap the liquid crystal layer (Fig. 9B and ¶0098 disclose liquid crystal light valves 208 do not overlap with the grating coupler 130), and is configured to diffract the illumination light (¶0078 discloses the transmission mode diffraction grating 132′ of the grating coupler 130 is configured to diffractively redirect concentrated light 102′ that is transmitted or passes through diffraction grating 132).
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 Kurokawa so that the grating-coupled light guide 100 may provide a relatively high coupling efficiency (¶0058).
Regarding claim 5, Kurokawa discloses the display device of claim 1, wherein the first surface is a first main surface of the second transparent substrate (SUB2) (Figs. 3-4 illustrate bottom surface of the second substrate SUB2), and the first main surface faces the first transparent substrate (SUB1) (Figs. 3-4 illustrate bottom surface of second substrate SUB2 faces the first substrate SUB1), the second surface is a side surface (E22) of the second transparent substrate (SUB2) (Fig. 2 and ¶0040 disclose the second substrate SUB2 includes end portions E21 and E22 extending in the first direction X), and the side surface (E22) intersects with the first main surface (Figs. 2-3), and the light emitting unit faces the second surface (E22) (Figs. 2-3 and ¶0043 disclose a light source unit LU is located above the first substrate SUB1 and disposed along the end portion E22).
4. Claim(s) 2 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li and in further view of Fattal (US 2017/0299794 A1, hereinafter referred as “Fattal”).
Regarding claim 2, Kurokawa discloses the display device of claim 1, wherein the first surface is a first main surface of the second transparent substrate (SUB2) (Figs. 3-4 illustrate bottom surface of the second substrate SUB2), and the first main surface faces the first transparent substrate (SUB1) (Figs. 3-4 illustrate bottom surface of second substrate SUB2 faces the first substrate SUB1), the second surface is a second main surface of the second transparent substrate (SUB2) (Figs. 3-4 illustrate the top surface of the second substrate SUB2), and the second main surface is located on a side opposite to the first main surface (Figs. 3-4 illustrate the bottom surface of substrate SUB2 faces the top surface of substrate SUB1).
Kurokawa as modified doesn’t disclose the light emitting unit faces the second surface.
However, in the same field of endeavor, Fattal discloses the light emitting unit faces the second surface (Fig. 6, 1B and ¶0049 disclose the grating coupler 120 may be a reflective grating coupler 120 having a reflection mode diffraction grating 122″ at a surface 114 of the plate light guide 110 that is opposite to the surface adjacent to the light source 106).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa since Fattal shows that the major-surface illumination is a conventional alternative to edge illumination and permits the incident illumination to be redirected into guided propagation by the diffraction grating.
5. Claim(s) 3, and 8-9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li and in further view of Fattal and still in further view of Brown et al. (US 2018/0373115 A1, hereinafter referred as “Brown”).
Regarding claim 3, Kurokawa as modified doesn’t disclose the display device of claim 2, wherein the diffractive optical element is formed into a belt-like shape, and the light emitting unit overlaps an end portion of the diffractive optical element.
However, in the same field of endeavor, Brown discloses wherein the diffractive optical element is formed into a belt-like shape (Figs. 21-22 and ¶0163 disclose the HBE 281 comprising input coupling grating 283 and output coupling gratings 284, 285 formed in a belt-like shape), and the light emitting unit (286) overlaps an end portion of the diffractive optical element (Figs. 21-22 and ¶0137 disclose input image node (IIN)… contains the microdisplay, laser module, beam expansion, collimation and relay optics and overlaps an end portion of the HBE 281).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of firstly, provide efficient coupling of image light into the waveguide and. secondly, ensure that once coupled-in, all of the needed angular content is transmitted down the waveguide with high efficiency (¶0243).
Regarding claim 8, Kurokawa as modified doesn’t disclose the display device of claim 3, wherein in the diffractive optical element, a thickness of the end portion is less than a thickness of other end portion.
However, in the same field of endeavor, Brown discloses wherein in the diffractive optical element, a thickness of the end portion is less than a thickness of other end portion (¶0151 disclose the gratings used in one or both of the HBE and DigiLens will have a tailored DE profile achieved by varying the thickness of the gratings along the propagation direction as shown in FIG. 15).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of achieving efficient and uniform extraction from the waveguide by varying the thickness (and modulation) across the grating (¶0240).
Regarding claim 9, Kurokawa doesn’t disclose the display device of claim 3, wherein in the diffractive optical element, a width of the end portion is less than a width of other end portion.
However, in the same field of endeavor, Li discloses wherein in the diffractive optical element, a width of the end portion is less than a width of other end portion (Fig. 6A and ¶0076 disclose the fan-shaped diffraction grating 132 has a width that increases from a first end toward a second end of the diffraction grating 132, where the width increase defines a fan angle φ).
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 Kurokawa so that the guided light 104 that is diffractively directed or coupled into the light guide 110 by the grating coupler 130 has controlled or predetermined propagation characteristics (i.e., spread angles) (¶0072).
6. Claim(s) 4 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, in further view of Fattal, still in further view of Brown and still in further view of Cornelissen et al. (US 2012/0113678 A1, hereinafter referred as “Cornelissen”).
Regarding claim 4, Kurokawa as modified doesn’t disclose the display device of claim 2, wherein the diffractive optical element is formed into a belt-like shape, and a plurality of light emitting units overlap both end portions of the diffractive optical element.
However, in the same field of endeavor, Brown discloses wherein the diffractive optical element is formed into a belt-like shape (Figs. 21-22 and ¶0163 disclose the HBE 281 comprising input coupling grating 283 and output coupling gratings 284, 285 formed in a belt-like shape), and [the light emitting unit overlaps the end portion] of the diffractive optical element (Figs. 21-22 and ¶0137 disclose input image node (IIN)… contains the microdisplay, laser module, beam expansion, collimation and relay optics and overlaps an end portion of the HBE 281).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of firstly, provide efficient coupling of image light into the waveguide and. secondly, ensure that once coupled-in, all of the needed angular content is transmitted down the waveguide with high efficiency (¶0243).
Kurokawa as modified still doesn’t disclose a plurality of light emitting units [at the] end portions of the diffractive optical element.
However, in the same field of endeavor, Cornelissen discloses a plurality of light emitting units [at the] end portions of the diffractive optical element (Fig. 8 and ¶0049 disclose the light guide apparatus has two light sources, the first light source 12 and the second light source 12, located at two opposite sides of the light guide plate 11).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to still further modify Kurokawa in order to increase the diffraction light intensity by illuminating the elongated diffractive light guide structure from both opposite ends rather than from only one end.
7. Claim(s) 6-7, and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, and in further view Cornelissen.
Regarding claim 6, Kurokawa as modified doesn’t disclose the display device of claim 5, wherein the diffractive optical element is formed into a belt-like shape, and the light emitting unit is located on an end side of the diffractive optical element.
However, in the same field of endeavor, Cornelissen discloses wherein the diffractive optical element (13) is formed into a belt-like shape (Fig. 3a and ¶0041 disclose first diffraction grating 13 formed into a belt-like shape on the first surface of light guide plate 11), and the light emitting unit (12) is located on an end side of the diffractive optical element (13) (Fig. 3a and ¶0041 discloses first light source 12 is coupled to a first side of the light guide plate 11).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa in order to efficiently couple illumination light into an end of the elongated refractive light-guide structure so that the light can propagate through the structure and be extracted by the diffraction grating.
Regarding claim 7, Kurokawa as modified doesn’t disclose the display device of claim 5, wherein the diffractive optical element is formed into a belt-like shape, and a plurality of light emitting units are located on an end side and other end side of the diffractive optical element.
However, in the same field of endeavor, Cornelissen discloses wherein the diffractive optical element (13) is formed into a belt-like shape (Fig. 3a and ¶0041 disclose first diffraction grating 13 formed into a belt-like shape on the first surface of light guide plate 11), and a plurality of light emitting units (12) are located on an end side and other end side of the diffractive optical element (13) (Figs. 4, 8 and ¶0049 disclose the light guide apparatus has two light sources, the first light source 12 and the second light source 12, located at two opposite sides of the light guide plate 11).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa in order to increase the diffraction light intensity by illuminating the elongated diffractive light guide structure from both opposite ends rather than from only one end.
Regarding claim 20, Kurokawa doesn’t disclose the display device of claim 6, wherein in the diffractive optical element, a width of an end portion is less than a width of other end portion.
However, in the same field of endeavor, Li discloses wherein in the diffractive optical element, a width of an end portion is less than a width of other end portion (Fig. 6A and ¶0076 disclose the fan-shaped diffraction grating 132 has a width that increases from a first end toward a second end of the diffraction grating 132, where the width increase defines a fan angle φ).
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 Kurokawa so that the guided light 104 that is diffractively directed or coupled into the light guide 110 by the grating coupler 130 has controlled or predetermined propagation characteristics (i.e., spread angles) (¶0072).
8. Claim(s) 10 and 18 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, and in further view Qi et al. (US 2014/0049726 A1, hereinafter referred as “Qi”).
Regarding claim 10, Kurokawa as modified doesn’t disclose the display device of claim 1, further comprising a light guide, wherein the light guide is located between the second transparent substrate and the diffractive optical element, and the light emitting unit faces the light guide.
However, in the same field of endeavor, Qi discloses further comprising a light guide (78) (Figs. 5-7 and ¶0045 disclose light guide plate 78), wherein the light guide (78) is located between the second transparent substrate (56) and the diffractive optical element (98) (Figs. 5-7 and ¶0054 disclose the diffractive structures 98 of region 90 formed on the lower surface of the light guide plate 78, thus light guide 78 is located between transparent substrate 56 and the diffractive structures 98), and the light emitting unit (72) faces the light guide (78) (Fig. 7 and ¶0046 disclose light 74 from light source 72 may be coupled into edge surface 76 of light guide plate 78).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa so that the light mixing efficiency is enhanced in region 90, the width D of region 90 (and the total width needed for effective mixing), may be relatively small, thereby reducing the size of light guide plate 78 without adversely affecting the quality of the light mixing that is performed by light guide plate 78 along its edge (¶0063).
Regarding claim 18, Kurokawa as modified doesn’t disclose the display device of claim 1, wherein the diffractive optical element comprises a holographic optical element or a liquid crystal element containing a cholesteric liquid crystal.
However, in a similar field of endeavor, Qi discloses wherein the diffractive optical element comprises a holographic optical element (abstract discloses a strip of light diffracting structures such as holographic structures or grating structures may be used to mix light from the light-emitting diodes along the border of the light guide plate) or a liquid crystal element containing a cholesteric liquid crystal.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa so that the light mixing efficiency is enhanced in region 90, the width D of region 90 (and the total width needed for effective mixing), may be relatively small, thereby reducing the size of light guide plate 78 without adversely affecting the quality of the light mixing that is performed by light guide plate 78 along its edge (¶0063).
9. Claim(s) 13-14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, and in further view Qi, still further view of Nakamura et al. (US 2023/0280518 A1, hereinafter referred as “Nakamura”) and still in further view of Cornelissen.
Regarding claim 13, Kurokawa as modified doesn’t disclose the display device of claim 10, wherein the light guide has a first side surface facing a side surface of the second transparent substrate, and a first end surface intersecting with the first side surface, and the light emitting unit faces the first end surface of the light guide.
However, in the same field of endeavor, Nakamura discloses wherein the light guide (LN1) has a first side surface facing a side surface (E21) of the second transparent substrate (20) (Fig. 6 and ¶0106 disclose the light source LS1 and the lens LN1 are opposed to each of the side surface 30C and the side surface E21), and a first end surface intersecting with the first side surface (Fig. 6 illustrates the end surface of lens LN1 intersects with the side surface of lens LN1 that faces side surface E21)…
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of efficiently transferring illumination light from the light guide into the transparent substrate while reducing undesired loss of light outside the intended optical path.
Kurokawa as modified still doesn’t disclose the light emitting unit faces the first end surface of the light guide.
However, in the same field of endeavor, Cornelissen discloses the light emitting unit faces the first end surface of the light guide (Figs. 4, 8 and ¶0041 disclose first light source 12 is coupled to a first side of the light guide plate 11).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to still further modify Kurokawa since direct coupling at the guide’s end is a known manner of injecting illumination into a planar light source for subsequent diffraction.
Regarding claim 14, Kurokawa as modified doesn’t disclose the display device of claim 10, wherein the light guide has a first side surface facing a side surface of the second transparent substrate, a first end surface intersecting with the first side surface, and a second end surface located on a side opposite to the first end surface, and a plurality of light emitting units face the first and second end surfaces of the light guide.
However, in the same field of endeavor, Nakamura discloses wherein the light guide (LN1) has a first side surface facing a side surface (E21) of the second transparent substrate (20) (Fig. 6 and ¶0106 disclose the light source LS1 and the lens LN1 are opposed to each of the side surface 30C and the side surface E21), and a first end surface intersecting with the first side surface (Fig. 6 illustrates the end surface of lens LN1 intersects with the side surface of lens LN1 that faces side surface E21), and a second end surface located on a side opposite to the first end surface (Fig. 6 illustrates the two end surface of lens LN1 located on opposite sides)…
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of efficiently transferring illumination light from the light guide into the transparent substrate while reducing undesired loss of light outside the intended optical path.
Kurokawa as modified still doesn’t disclose a plurality of light emitting units face the first and second end surfaces of the light guide.
However, in the same field of endeavor, Cornelissen discloses a plurality of light emitting units face the first and second end surfaces of the light guide (Figs. 4, 8 and ¶0049 disclose the light guide apparatus has two light sources, the first light source 12 and the second light source 12, located at two opposite sides of the light guide plate 11).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to still further modify Kurokawa in order to achieve a much stronger diffraction light intensity (¶0012).
10. Claim(s) 15 and 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, and in further view of Brown.
Regarding claim 15, Kurokawa as modified doesn’t disclose the display device of claim 1, wherein the light emitting unit comprises: a first light emitting element configured to emit light having a first wavelength range; and a second light emitting element configured to emit light having a second wavelength range different from the first wavelength range, and the diffractive optical element comprises: a first diffractive element configured to diffract the illumination light having the first wavelength range; and a second diffractive element configured to diffract the illumination light having the second wavelength range.
However, in the same field of endeavor, Brown discloses wherein the light emitting unit comprises: a first light emitting element configured to emit light having a first wavelength range; and a second light emitting element configured to emit light having a second wavelength range different from the first wavelength range (Figs. 32A-32C and ¶0175 disclose red, green and blue illumination channels having different wavelength ranges), and the diffractive optical element comprises: a first diffractive element configured to diffract the illumination light having the first wavelength range; and a second diffractive element configured to diffract the illumination light having the second wavelength range (Figs. 32A-32C and ¶0075 disclose RGB diffracting layers having wavelength dependent diffraction efficiency characteristics corresponding to respective color channels).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa in order to accommodate the spectral characteristics of RGB illumination and thereby separately control different wavelength bands.
Regarding claim 17, Kurokawa doesn’t disclose the display device of claim 15, wherein the first diffractive element is provided at a position different from the second diffractive element, the first light emitting element overlaps the first diffractive element, and the second light emitting element overlaps the second diffractive element.
However, in the same field of endeavor, Li discloses wherein the first diffractive element is provided at a position different from the second diffractive element (Figs. 9B and 9C illustrate the diffractive elements 130 positioned at different locations), the first light emitting element overlaps the first diffractive element, and the second light emitting element overlaps the second diffractive element (Fig. 9C illustrates each light emitting element 120 respectively overlaps the diffractive elements 130).
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 Kurokawa in order to have a source to grating alignment for efficiently coupling incident illumination into a diffractive guide.
11. Claim(s) 19 is/are rejected under 35 U.S.C. 103 as being unpatentable over Kurokawa in view of Li, in further view Cornelissen, and still in further view of Brown.
Regarding claim 19, Kurokawa as modified doesn’t disclose the display device of claim 6, wherein in the diffractive optical element, a thickness of an end portion is less than a thickness of other end portion.
However, in the same field of endeavor, Brown discloses wherein in the diffractive optical element, a thickness of an end portion is less than a thickness of other end portion (¶0240 discloses a wedged grating (by inclining the cell watts) such that the hologram thickness increases in the direction of propagation. Typically, the grating thickness may vary from 1.0-1.2 micron up to 2.8-3.0 micron).
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to further modify Kurokawa for the purpose of achieving efficient and uniform extraction from the waveguide by varying the thickness (and modulation) across the grating (¶0240).
Allowable Subject Matter
12. Claims 11-12 and 16 are 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.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to PRIYANK J SHAH whose telephone number is (571)270-3732. The examiner can normally be reached on 10:00 - 6:00 M-F.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Ghebretinsae, Temesghen can be reached on (571) 272-3017. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/PRIYANK J SHAH/Primary Examiner, Art Unit 2626
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