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
Six (6) sheets of drawings were filed on August 12, 2024 and have been accepted by the examiner.
Specification
Applicant’s cooperation is requested in correcting any errors of which applicant may become aware in the specification.
Inventorship
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 2, 7 and 12 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Shi et al. (US 2015/0338577 A1), hereafter Shi.
Regarding claims 1 and 2; Shi discloses a method using a compact mid-infrared polarization splitter and rotator (PSR) (see Figure 1) comprising:
receiving an input signal at a waveguide, the input signal (Optical input, TE0, TM0) having a transverse electric (TE) mode and a transverse magnetic (TM) mode, wherein the TE mode is a zero order or higher TE mode;
conditioning, by a taper of the waveguide (Polarization rotator: bi-level taper 110), the input signal to convert the TM mode to an additional TE mode, wherein the additional TE mode is a zero order or higher TE mode (see paragraphs 27-42, the TM0 mode at the Optical input is converted to the TE1 mode within the polarization rotator: bi-level taper 110);
bifurcating, after the conditioning and by a bifurcation section of the waveguide (Polarization splitter: adiabatic coupler 120) positioned after the taper, the input signal into a first branch (1st branch 121/131) and a second branch (2nd branch 122/132) of the waveguide (See Figure 1);
outputting, out of the first branch (1st branch 131), a first output signal having the TE mode (TE0); and
outputting, out of the second branch (2nd branch 132), a second output signal having the additional TE mode (TE0);
wherein conditioning further comprises rotating the TM mode (TM0) into the additional TE mode (TE1), and wherein the second branch (2nd branch 122/132) conditions the additional TE mode (TE1) of the input signal into the second output signal having a zero order TE mode (TE0; see Figure 1).
Regarding claims 7 and 12; Shi discloses a device comprising:
a substrate (SOI substrate; see paragraph 27);
a waveguide (see Figure 1) coupled to the substrate and configured to receive an input signal (Optical Input is received in the input waveguide section 100) having a transverse electric (TE) mode and a transverse magnetic (TM) mode (TE0 and TM0), wherein the TE mode (TE0) is a zero order mode or higher;
a taper (taper-rib waveguide 113) of the waveguide configured to condition the input signal to convert the TM mode (TM0) to an additional TE mode (TE1; see paragraph 24); and
a bifurcation section (120) of the waveguide after the taper forming a first branch (1st branch 121/131) and a second branch (2nd branch 122/132) of the waveguide, wherein the first branch (121/131) is configured to diverge from the second branch (122/132) after the bifurcation section (120), wherein the first branch (121/131) is configured to output a first output signal having the TE mode (TE0), and wherein the second branch (122/132) is configured to condition the additional TE mode (TE1) into a zero order TE mode (TE0), and configured to output a second output signal having the zero order TE mode (TE0);
wherein the first branch (121,131) includes a first width and the second branch (122/132) includes a second width, and wherein at a distance after the bifurcation section (120) the first width is greater than the second width (see Figure 1).
Claims 1, 2, 7, and 12 are rejected under 35 U.S.C. 102(a)(2) as being anticipated by Tambasco et al. (US 2025/0035839 A1), hereafter Tambasco.
Regarding claims 1 and 2; Tambasco discloses a method using a compact mid-infrared polarization splitter and rotator (PSR) (PSR 100; see Figure 1) comprising:
receiving an input signal (Optical Signal 150; see Figure 1 and paragraph 19) at a waveguide (Waveguides 115), the input signal (150) having a transverse electric (TE) mode and a transverse magnetic (TM) mode (see paragraph 19), wherein the TE mode is a zero order or higher TE mode;
conditioning, by a taper of the waveguide (the taper is formed in the middle part of Rotator 105; see Figure 1 and paragraph 23), the input signal to convert the TM mode to an additional TE mode, wherein the additional TE mode is a zero order or higher TE mode (see paragraph 34, Figure 1 and Figure 2);
bifurcating, after the conditioning and by a bifurcation section (the section of splitter 110 where waveguide portions 115 and 125 are closely spaced and coupled) of the waveguide (see Figure 1) positioned after the taper (the tapered portion of Rotator 105), the input signal into a first branch (115) and a second branch (125) of the waveguide (See Figure 1);
outputting, out of the first branch (115), a first output signal having the TE mode (TE0; see Figures 1 and 2); and
outputting, out of the second branch (125), a second output signal having the additional TE mode (TE0; see Figures 1 and 2);
wherein conditioning further comprises rotating the TM mode (TM0) into the additional TE mode (TE1), and wherein the second branch (125) conditions the additional TE mode (TE1) of the input signal into the second output signal having a zero order TE mode (TE0; see Figure 2; see paragraphs 34-36).
Regarding claims 7 and 12; Tambasco discloses a device comprising:
a substrate (material layers forming the optical waveguide structure of Tambasco inherently form a substrate; see paragraph 14);
a waveguide (115/120/125; see Figures 1 and 2) coupled to the substrate and configured to receive an input signal (150) having a transverse electric (TE) mode and a transverse magnetic (TM) mode (see paragraph 19 and Figure 2), wherein the TE mode (TE0) is a zero order mode or higher;
a taper (flared/tapered section in rotator 105; see Figure 1) of the waveguide configured to condition the input signal to convert the TM mode (TM0) to an additional TE mode (see paragraphs 34-35); and
a bifurcation section (the section of splitter 110 where waveguide portions 115 and 125 are closely spaced and coupled) of the waveguide after the taper forming a first branch (115) and a second branch (125) of the waveguide, wherein the first branch (115) is configured to diverge from the second branch (125) after the bifurcation section (110), wherein the first branch (115) is configured to output a first output signal having the TE mode (TE0), and wherein the second branch (125) is configured to condition the additional TE mode (TE1) into a zero order TE mode (TE0), and configured to output a second output signal having the zero order TE mode (TE0) (see Figures 1 and 2; see paragraphs 34-38);
wherein the first branch (115) and the second branch (125) are each configured to curve after the bifurcation section;
wherein the first branch (115) includes a first width and the second branch (125) includes a second width, and wherein at a distance after the bifurcation section (110) the first width is greater than the second width (see Figures 1 and 2).
Claims 1, 2, 7-9, 12, 17, and 18 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Testa et al. (US 2018/0316458 A1), hereafter Testa.
Regarding claims 1 and 2; Testa discloses a method using a compact mid-infrared polarization splitter and rotator (PSR) (polarization handling block 102; see Figure 1b; see paragraph 38) comprising:
receiving an input signal at a waveguide (an optical signal include TE and TM modes is received by optical waveguide section 142 at the input of section 102a of the polarization handling block 102; see paragraphs 43-45), the input signal having a transverse electric (TE) mode and a transverse magnetic (TM) mode, wherein the TE mode is a zero order or higher TE mode (TE0; see paragraph 45);
conditioning (see paragraph 44), by a taper of the waveguide (152), the input signal to convert the TM mode (TM) to an additional TE mode (TE1), wherein the additional TE mode is a zero order or higher TE mode (TE1);
bifurcating (see paragraph 46), after the conditioning and by a bifurcation section (154) of the waveguide positioned after the taper (152), the input signal into a first branch (156a) and a second branch (156b) of the waveguide (see Figure 1b);
outputting, out of the first branch (158a/160a), a first output signal having the TE mode (TE0); and
outputting, out of the second branch (158b/160b), a second output signal having the additional TE mode (TE0);
wherein conditioning further comprises rotating the TM mode into the additional TE mode (TE1; see paragraph 44), and wherein the second branch (158b/160b) conditions the additional TE mode (TE1) of the input signal into the second output signal having a zero order TE mode (TE0; see paragraphs 47-48).
Regarding claims 7-9 and 12; Testa discloses a device comprising:
a substrate (164);
a waveguide (142/144/156a/156b/158a/158a/1601/160b) coupled to the substrate (164) and configured to receive an input signal (see paragraphs 43-45) having a transverse electric (TE) mode (TE0) and a transverse magnetic (TM) mode (TM), wherein the TE mode (TE0) is a zero order mode or higher;
a taper (152) of the waveguide configured to condition the input signal to convert the TM mode (TM) to an additional TE mode (TE1; see paragraph 44-45); and
a bifurcation section (154) of the waveguide after the taper (152) forming a first branch (156a) and a second branch (156b) of the waveguide, wherein the first branch (156a) is configured to diverge from the second branch (156b) after the bifurcation section (see Figure 1), wherein the first branch (158a/160a) is configured to output a first output signal having the TE mode (TE0), and wherein the second branch (158b/160b) is configured to condition the additional TE mode (TE1) into a zero order TE mode (TE0), and configured to output a second output signal having the zero order TE mode (TE0) (see paragraphs 46-48);
wherein the first branch and the second branch are each configured to curve after the bifurcation section (154; see Figure 1b);
wherein the first branch has a first taper which widens after the bifurcation section (154) and the second branch has a second taper which narrows after the bifurcation section (154; see Figure 1; see paragraph 46; the first branch widens from section 156a to 158a, and the second section narrows from section 156b to 158b);
wherein the first branch (156a/158a/160a) includes a first width and the second branch (156b/158b/160b) includes a second width, and wherein at a distance after the bifurcation section (154) the first width (width of 158a) is greater than the second width (width of 158b; see Figure 1b)
Regarding claims 17 and 18; Testa discloses an apparatus (102; see Figure 1b) comprising:
a waveguide (142) configured to receive an input signal having a transverse electric (TE) mode and a transverse magnetic (TM) mode, wherein the TE mode is a zero order mode or higher (see paragraphs 43-45);
a taper (152) of the waveguide, wherein the taper is configured to condition the input signal to convert the TM mode to an additional TE mode (see paragraphs 43-45);
a first branch (156a/158a/160a) coupled to the taper (152), wherein the first branch is configured to output a first output signal having TE mode (see paragraphs 46-48); and
a second branch (156b/158b/160a) coupled to the taper, wherein the second branch is configured to condition the additional TE mode into a zero order TE mode, and configured to output a second output signal having the zero order TE mode (see paragraphs 46-48);
wherein the first branch (156a) and the second branch (156b) have equal widths (at a midpoint of section 154) at a bifurcation section (154) of the waveguide, and wherein the first branch and the second branch are each coupled to the taper (152; see Figure 1b).
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 3-6 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Shi et al. (US 2015/0338577 A1), hereafter Shi.
Regarding claim 3; Shi discloses the method of claim 1 as discussed above, but fails to specific a wavelength range. Shi does teach that the invention is wavelength-insensitive (see paragraphs 17-18). Thus, a person of ordinary skill in the art would have found it obvious to use any desired wavelength for the input signal, including wherein the input signal has a wavelength in a range between 2.0 µm and 15.0 µm, since the device of Shi is wavelength insensitive and would be expected to perform equally well regardless.
Regarding claim 4; Shi discloses the method of claim 1 as discussed above, but fails to specific a wavelength range. Shi does teach that the invention is wavelength-insensitive (see paragraphs 17-18). Thus, a person of ordinary skill in the art would have found it obvious to use any desired wavelength for the input signal, including wherein the input signal has a wavelength in a range between 3.1 µm and 3.5 µm, since the device of Shi is wavelength insensitive and would be expected to perform equally well regardless.
Shi does not disclose a specific value for polarization conversion loss of the second optical signal. Shi does explicitly disclose all of the claimed structural features as discussed above with respect to claims 1 and 3. Claim 4 contains properties or functions that are presumed to be inherent to the structure. When a structure recited in a reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent (see MPEP 2112.01). The patentability of a product depends only on the claimed structural limitations of the product. Shi discloses a compact mid-infrared polarization splitter that is substantially identical to the claimed compact mid-infrared polarization splitter, therefore the claimed properties or functions are presumed to be inherent. The burden is on the applicant to show that the prior art device does not possess the claimed properties or is not capable of these functional characteristics. (See MPEP 2112.01). Thus, it is presumed that the polarization splitter having the structure disclosed by Shi also has a polarization conversion loss of the second output signal is less than or equal to 0.5 dB.
Regarding claim 5; Shi does not disclose a specific value for polarization conversion loss of the second optical signal or a specific value for insertion loss at the first output signal. Shi does explicitly disclose all of the claimed structural features as discussed above with respect to claims 1 and 3. Claim 4 contains properties or functions that are presumed to be inherent to the structure. When a structure recited in a reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent (see MPEP 2112.01). The patentability of a product depends only on the claimed structural limitations of the product. Shi discloses a compact mid-infrared polarization splitter that is substantially identical to the claimed compact mid-infrared polarization splitter, therefore the claimed properties or functions are presumed to be inherent. The burden is on the applicant to show that the prior art device does not possess the claimed properties or is not capable of these functional characteristics. (See MPEP 2112.01). Thus, it is presumed that the polarization splitter having the structure disclosed by Shi also has a polarization conversion loss of the second output signal is less than or equal to 0.9 dB, and an insertion loss at the first output signal is less than or equal to 0.5 dB
Regarding claim 6; Shi does not disclose a crosstalk value. Shi does explicitly disclose all of the claimed structural features as discussed above with respect to claims 1 and 3. Claim 4 contains properties or functions that are presumed to be inherent to the structure. When a structure recited in a reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent (see MPEP 2112.01). The patentability of a product depends only on the claimed structural limitations of the product. Shi discloses a compact mid-infrared polarization splitter that is substantially identical to the claimed compact mid-infrared polarization splitter, therefore the claimed properties or functions are presumed to be inherent. The burden is on the applicant to show that the prior art device does not possess the claimed properties or is not capable of these functional characteristics. (See MPEP 2112.01). Thus, it is presumed that the polarization splitter having the structure disclosed by Shi also has at least one crosstalk value between the first output signal and the second output signal is less than 20 dB. The examiner further notes that it’s well established in the optical waveguide art that minimizing crosstalk reduces loss and improves the quality of the optical output, and one of ordinary skill in the art would have found it obvious to minimize optical crosstalk by spacing the output waveguides or provide for a crosstalk of 20 dB or less to minimize interference and optical loss and to improve the quality of the output signal.
Regarding claim 8; Shi discloses the device of claim 7, wherein the first branch and the second branch diverge (see Figure 1) and the second branch (122, 132) is configured to curve (2nd branch 132 curves; see Figure 1), but does not disclose that the first branch is configured to curve after the bifurcation section (1st branch 121/131 remains straight in Figure 1). Shi teaches that a prior art configuration (see Figure 8) provided first and second branches that are both configured to curve. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to further configure the first branch to curve in the embodiment of Figure 1 of Shi for the purpose of routing an optical signal to a desired output location, since this was a known alternative configuration in the prior art 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).
Claims 10, 11, 13-16, 19, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Testa et al. (US 2018/0316458 A1), hereafter Testa.
Regarding claim 10; Testa discloses the device of claim 7, but fails to specify a specific length for the taper. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to provide any desired taper length sufficient to ensure maximized conversion with minimize optical loss, including wherein the taper (152) includes a length between 7 µm and 15 µm prior to the bifurcation section (154), 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 11; Testa discloses the device of claim 7, wherein the substrate (164; see Figure 1b) has a length which extends along the waveguide, the taper, the first branch, and the second branch (144/152/154/156a/156b/158a/158b/160a/160b), but fails to disclose a specific length. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to have the substrate extend any desired length for the purpose of accommodating optical waveguide sections designed to maximize optical coupling efficiencies and minimize optical loss, including wherein the length is between 50 µm and 100 µm, 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 13; Testa discloses the device of claim 7, wherein the second branch (156b) includes a first curve and a second curve (see Figure 1b), but fails to disclose specific dimensions associated with the curve. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to provide a curve of any desired dimension designed to minimize optical loss within the curved region, including wherein the first curve includes a first radius of curvature between 2 µm and 12 µm, wherein the second curve includes a second radius of curvature between 7 µm and 17 µm, and wherein the first branch includes a first S-bend and a second S-bend which includes a combined radius of curvature between 3 µm and 13 µm, 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 14; Testa discloses the device of claim 7, wherein the bifurcation section (154) includes a slot (gap between waveguide section 156a and waveguide section 156b), but fails to disclose specific dimensions associated therewith. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to form the gap with any desired width that is optimized to allow for efficient coupling of the TE1 mode from 156a to 156b with minimal loss, including a width between 50 nm and 140 nm, 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 15; Testa disclose the device of claim 7 but fails to disclose specific dimensions. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to form the first and second branches to have any desired thicknesses sufficient to support and confine the desired modes with minimal optical loss, including wherein the first branch and the second branch have a thickness measured from a surface of the substrate between 400 nm and 600 nm, 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 16; Testa discloses the device of claim 8, wherein at a distance after the bifurcation section (154) the first branch (156a) and the second branch (156b) each taper into fully-etched waveguides (158a/160a and 158b/160b) over a length, but fails to specify a particular length. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to provide a taper of any desired length that minimizes loss, including a length between 5 µm and 20 µm, 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) and since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art (In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980)), and since such a modification would have involved a mere change in the size of a component and it has been held that a change in size is generally recognized in as being within the level of ordinary skill in the art (In re Rose, 105 USPQ 237 (CCPA 1955)) and that, where the only difference between the prior art and the claims is a recitation of relative dimensions of the claimed device and a device having the claimed relative dimensions would not perform differently than the prior art device, the claimed device is not patentably distinct from the prior art device (In re Gardner v. TEC Systems, Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984)).
Regarding claim 19; Although not explicitly discloses, Figure 1B of Testa suggests that the first branch curves after the taper at an angle between 10 and 35 degrees (see Figure 1b; first branch 156 curves at the beginning of section 154 on the side facing second branch 156b), and thus this arrangement would have been evident to a person of ordinary skill in the art before the effective filing date of the present invention.
Regarding claim 20; Testa discloses the limitations of claim 17, wherein the waveguide, taper, first branch, and second branch are at least partially coupled to a substrate (164), but fails to disclose wherein the waveguide, taper, first branch, and second branch are at least partially encapsulated by a silicon dioxide (SiO2) layer. Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to further provide a cladding of silicon dioxide on top of the waveguide and substrate of Figure 1b for the purpose of efficiently confining light within the waveguide while protecting the waveguide from damage, since the use of silicon dioxide claddings for this purpose is elementary and well-known in the optical waveguide arts and no novel or unexpected advantages would occur, thereby providing the waveguide, taper, first branch, and second branch at least partially encapsulated by a silicon dioxide (SiO2) layer.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure: The following references disclose related polarization couplers:
Sugiyama (US 2025/0383496 A1), see entire document;
Roth (US 12,287,512 B2), see entire document;
Ummethaia (US 12,204,147 B2), see entire document;
Safian et al. (US 11,409,038 B1), see entire document;
Xie et al. (CN 112327411 A), see Figure 1;
Liu et al. (US 10,809,459 B2), see entire document;
Lin et al. (US 10,684,416 B2), see Figure 1;
Park et al. (US 2020/0096700 A1), see entire document;
Damas et al. (WO 2019/205918 A1), see Figure 4;
Socci et al. (US 2017/0315294 A1), see entire document;
Oka (US 2017/0176679 A1), see entire document; and
Little et al. (US 8,238,697 B2), see entire document.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MICHELLE R CONNELLY whose telephone number is (571)272-2345. 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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/MICHELLE R CONNELLY/Primary Examiner, Art Unit 2874
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