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 .
Response to Amendment
Applicant's Amendment filed 2/9/2026 has been fully considered and entered.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1-20 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
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, 3-16, and 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Tol in US 20140321797 A1 (hereinafter "Van der Tol") in view of Tu et al. in US 20180059324 A1 (hereinafter "Tu").
Regarding claims 1, 3, and 7, Van der Tol discloses an optical polarization converter (see Title), comprising:
an optical waveguide (see Para. 31; see Fig. 1), wherein:
a portion of the optical waveguide has a cross-section that is asymmetric (see Fig. 1), with respect to a horizontal axis (x-axis) and a vertical axis (y-axis), at a plurality of points along a length of the portion (Fig. 1 shows asymmetry at a continuous plurality of points along the length of the portion);
wherein the portion of the optical waveguide includes one or more outer cladding sidewalls (the slanted sidewall of the upper cladding layer 100 is interpreted as an outer cladding sidewall) having, relative to the vertical axis (y-axis), a slant at a non-90 degree angle (see Fig. 1); but fails to teach that
the portion of the optical waveguide is tapered along the length of the portion (claim 1);
wherein the portion of the optical waveguide includes a plurality of sub-portions that are associated with respective taper ratios, wherein each of the plurality of sub-portions has a different taper rate (claim 3); or
at least one of: another portion of the optical waveguide has a cross-section that is symmetric at one or more points along a length of the other portion; or the other portion of the optical waveguide is not tapered along the length of the other portion (claim 7).
Tu discloses a polarization converting device including:
the portion of the optical waveguide includes a plurality of sub-portions that are associated with respective taper ratios, and each of the plurality of sub-portions has a different taper rate in a same direction and is tapered along a portion of the length (the taper regions of Figure 7, specifically w3 to w4, w5 to w6, and w6 to w7, are all positively tapered, i.e., not reverse-tapered, and none of these share the same taper rate; the added black lines in the annotation below are parallel and help to make the taper regions more evident; see also Para. 80 and 83, note recitation of “first waveguide 2021 of the polarization rotation region waveguide 202”; note that Table 1 explicitly discloses tapers from w2 to w7 since the numbers continuously decrease and are never constant, although some are but slight changes, see Examiner-created Table 1 below) (claim 1);
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Examiner-created Table 1
wherein the plurality of sub-portions comprises at least three sub-portions (Tu discloses at least 3 distinct sub-portions, namely w2 to w3, w3 to w4, w4 to w5, w5 to w6, and w6 to w7; Tu’s “sub-portions” are 2-micron-long portions and thus interpreted as sub-portions; see Table 1, Fig. 7, and Para. 83; note Examiner-created Table 1) (claim 3);
wherein at least one of:
another portion of the optical waveguide has a cross-section that is symmetric at one or more points along a length of the other portion (Fig. 5 shows that the first waveguide 2021 is symmetric at all cross-sections of the first waveguide) (claim 7).
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have the taper(s) of Tu in the polarization converter of Van der Tol for the purpose of effecting a gradual change in cross-section between differently-sized waveguides or spot sizes thereby ensuring light remains in a desired mode or is converted to a desired mode, depending on the taper selected, and results in low-loss, efficient coupling between waveguide segments while minimizing reflection and/or radiation losses that would otherwise occur.
Regarding claim 4, Van der Tol 1/Tu discloses the optical polarization converter of claim 1 as discussed above, wherein the optical polarization converter is configured to convert a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode.
Since TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode, whereby the TE mode and TM mode are interpreted as first and second fundamental polarization modes.
Regarding claim 5, Van der Tol/Tu discloses the optical polarization converter of claim 1 as discussed above, wherein the portion of the optical waveguide is configured to convert a polarization mode of an optical beam (necessarily present) from a first fundamental polarization mode to a second fundamental polarization mode as the optical beam propagates from an input end of the portion of the optical waveguide to an output end of the portion of the optical waveguide.
Since input TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting from a first fundamental polarization mode to a second fundamental polarization mode as the optical beam propagates from an input end of the portion of the optical waveguide to an output end of the portion of the optical waveguide, whereby the TE mode and TM mode are interpreted as first and second fundamental polarization modes.
Regarding claim 6, Van der Tol/Tu discloses the optical polarization converter of claim 1 as discussed above, wherein the portion of the optical waveguide is configured to rotate a polarization mode angle of an optical beam (necessarily present) as the optical beam (necessarily present) propagates from an input end (1106) of the portion of the optical waveguide to an output end (1104) of the portion of the optical waveguide.
Since input TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of rotating a polarization mode angle of an optical beam as the optical beam propagates from an input end of the portion of the optical waveguide to an output end of the portion of the optical waveguide.
Regarding claims 8 and 11, Van der Tol discloses an optical polarization converter (see Title), comprising:
an optical waveguide (see Para. 31; see Fig. 1), wherein:
a portion of the optical waveguide has an asymmetric (see Fig. 1), with respect to a horizontal axis (x-axis) and a vertical axis (y-axis), cross-section profile;
wherein the portion of the optical waveguide includes one or more outer cladding sidewalls (the slanted sidewall of the upper cladding layer 100 is interpreted as an outer cladding sidewall) having, relative to the vertical axis (y-axis), a slant at a non-90-degree angle (see Fig. 1); but fails to teach that
the portion of the optical waveguide is tapered along the length of the portion (claim 8); or
the portion of the optical waveguide is associated with a plurality of different taper ratios (claim 11).
Tu discloses a polarization converting device including:
the portion of the optical waveguide includes a plurality of sub-portions that are associated with respective taper ratios, and each of the plurality of sub-portions has a different taper rate in a same direction and is tapered along a length of the portion (the taper regions of Figure 7, specifically w3 to w4, w5 to w6, and w6 to w7, are all positively tapered, i.e., not reverse-tapered, and none of these share the same taper rate; the added black lines in the annotation below are parallel and help to make the taper regions more evident; see also Para. 80 and 83, note recitation of “first waveguide 2021 of the polarization rotation region waveguide 202”; note that Table 1 explicitly discloses tapers from w2 to w7 since the numbers continuously decrease and are never constant, although some are but slight changes, see Examiner-created Table 1 above) (claim 8);
wherein the plurality of sub-portions comprises at least three sub-portions (Tu discloses at least 3 distinct sub-portions, namely w2 to w3, w3 to w4, w4 to w5, w5 to w6, and w6 to w7; Tu’s “sub-portions” are 2-micron-long portions and thus interpreted as sub-portions; see Table 1, Fig. 7, and Para. 83; note Examiner-created Table 1) (claim 11).
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have the taper of Tu in the polarization converter of Van der Tol for the purpose of effecting a gradual change in cross-section between differently-sized waveguides or spot sizes thereby ensuring light remains in a desired mode or is converted to a desired mode, depending on the taper selected, and results in low-loss, efficient coupling between waveguide segments while minimizing reflection and/or radiation losses that would otherwise occur.
Regarding claim 9, Van der Tol/Tu discloses the optical polarization converter of claim 8 as discussed above, wherein the optical waveguide (see Para. 31; see Fig. 1) is a semiconductor optical waveguide (Fig. 1 shows a waveguide with InP and InGaAsP layers; INP and InGaAsP are two well-known semiconductor alloys commonly chosen for optical applications, including optical waveguides).
Regarding claim 10, Van der Tol/Tu discloses the optical polarization converter of claim 8 as discussed above, wherein a cross-section of the portion of the optical waveguide (see Para. 31; see Fig. 1) does not have symmetry associated with the horizontal axis (x-axis) and does not have symmetry associated with the vertical axis (y-axis; observe Fig. 1 where the trapezoid is asymmetric both vertically and horizontally).
Regarding claim 12, Van der Tol/Tu discloses the optical polarization converter of claim 8 as discussed above, wherein the portion of the optical waveguide is configured to convert a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode.
Since TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode, whereby the TE mode and TM mode are interpreted as first and second fundamental polarization modes.
Regarding claim 13, Van der Tol/Tu discloses the optical polarization converter of claim 12 as discussed above, wherein the first fundamental polarization mode is a fundamental transverse electric (TE) polarization mode and the second fundamental polarization mode is a fundamental transverse magnetic (TM) polarization mode.
Since TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode, whereby the TE mode and TM mode are interpreted as first and second fundamental polarization modes.
Regarding claim 14, Van der Tol/Tu discloses the optical polarization converter of claim 12 as discussed above, wherein the first fundamental polarization mode is a fundamental transverse magnetic (TM) polarization mode and the second fundamental polarization mode is a fundamental transverse electric (TE) polarization mode.
Since TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode, whereby the TM mode and TE mode are interpreted as first and second fundamental polarization modes. Para. 31 teaches both TE to TM conversion, or alternatively, TM to TE conversion.
Regarding claims 15 and 18, Van der Tol discloses an optical polarization converter (see Title), comprising:
an optical waveguide (see Para. 31; see Fig. 1), wherein:
a portion of the optical waveguide is asymmetric along a length of the portion (see Fig. 1);
wherein the portion of the optical waveguide includes one or more outer cladding sidewalls (the slanted sidewall of the upper cladding layer 100 is interpreted as an outer cladding sidewall) having, relative to the vertical axis (y-axis), a slant at a non-90-degree angle (see Fig. 1); but fails to teach that
the portion of the optical waveguide is tapered (claim 15); or
the portion of the optical waveguide is associated with a plurality of taper ratios (claim 18).
Tu discloses a polarization converting device including:
the portion of the optical waveguide includes a plurality of sub-portions that are associated with respective taper ratios, and each of the plurality of sub-portions has a different taper rate in a same direction and is tapered along a portion of the length (the taper regions of Figure 7, specifically w3 to w4, w5 to w6, and w6 to w7, are all positively tapered, i.e., not reverse-tapered, and none of these share the same taper rate; the added black lines in the annotation below are parallel and help to make the taper regions more evident; see also Para. 80 and 83, note recitation of “first waveguide 2021 of the polarization rotation region waveguide 202”; note that Table 1 explicitly discloses tapers from w2 to w7 since the numbers continuously decrease and are never constant, although some are but slight changes, see Examiner-created Table 1 above) (claim 15);
wherein the plurality of sub-portions comprises at least three sub-portions (Tu discloses at least 3 distinct sub-portions, namely w2 to w3, w3 to w4, w4 to w5, w5 to w6, and w6 to w7; Tu’s “sub-portions” are 2-micron-long portions and thus interpreted as sub-portions; see Table 1, Fig. 7, and Para. 83; note Examiner-created Table 1) (claim 18).
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have the taper of Tu in the polarization converter of Van der Tol for the purpose of effecting a gradual change in cross-section between differently-sized waveguides or spot sizes thereby ensuring light remains in a desired mode or is converted to a desired mode, depending on the taper selected, and results in low-loss, efficient coupling between waveguide segments while minimizing reflection and/or radiation losses that would otherwise occur.
Regarding claim 16, Van der Tol/Tu discloses the optical polarization converter of claim 15 as discussed above, wherein the portion of the optical waveguide is asymmetric (see Fig. 1) with respect to a horizontal axis (x-axis) and to the vertical axis (y-axis) of the optical waveguide (Fig. 1 shows asymmetry along both the x-axis and y-axis).
Regarding claim 19, Van der Tol/Tu discloses the optical polarization converter of claim 15 as discussed above, wherein the optical waveguide is configured to convert a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode.
Since TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of converting a polarization mode of an optical beam from a first fundamental polarization mode to a second fundamental polarization mode, whereby the TE mode and TM mode are interpreted as first and second fundamental polarization modes.
Regarding claim 20, Van der Tol/Tu discloses the optical polarization converter of claim 15 as discussed above, wherein the portion of the optical waveguide is configured to rotate a polarization mode angle of an optical beam (necessarily present) as the optical beam (necessarily present) propagates from an input end (1106) of the portion of the optical waveguide to an output end (1104) of the portion of the optical waveguide.
Since input TE and/or TM modes can be rotated to output the other as in Van der Tol Para. 31, the disclosed polarization converter is considered to be capable of rotating a polarization mode angle of an optical beam as the optical beam propagates from an input end of the portion of the optical waveguide to an output end of the portion of the optical waveguide.
Claim(s) 2 and 17 is/are rejected under 35 U.S.C. 103 as being unpatentable over Van der Tol in US 20140321797 A1 (hereinafter "Van der Tol") in view of Tu et al. in US 20180059324 A1 (hereinafter "Tu") as applied above, and in further view of Goi et al. in US 20160178842 A1 (hereinafter "Goi").
Regarding claim 2, Van der Tol/Tu discloses the optical polarization converter of claim 1 as discussed above, but fails to teach that the portion of the optical waveguide further includes at least one of:
one or more stepped sidewalls;
one or more curved sidewalls;
a core with a stepped thickness or a graded refractive index; or
a cladding with a stepped thickness or a graded refractive index.
Goi discloses a polarization converter (10) wherein the portion of the optical waveguide (see Para. 70 and Fig. 3) further includes:
one or more curved sidewalls (see Para. 99 and Fig. 6);
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have the one or more curved sidewalls as taught by Goi in the suggested device combination of Van der Tol/Tu for the purpose of improving the polarization extinction ratio and shortening the waveguide thereby achieving a smaller, more desirable device.
Regarding claim 17, Van der Tol/Tu discloses the optical polarization converter of claim 15 as discussed above, wherein the portion of the optical waveguide is asymmetric (see Fig. 1) with respect to a horizontal axis (x-axis) and to the vertical axis (y-axis) of the optical waveguide (Fig. 1 shows asymmetry along both the x-axis and y-axis); but fails to teach that the portion of the optical waveguide is curved in association with a bend radius.
Goi disclose a polarization converter (10) wherein the portion of the optical waveguide is curved in association with a bend radius (see Para. 99 and Fig. 6).
Accordingly, it would have been obvious to a person having ordinary skill in the art before the effective filing date of the claimed invention to have the portion of the optical waveguide curved in association with a bend radius as taught by Goi in the suggested device combination of Van der Tol/Tu for the purpose of improving the polarization extinction ratio and shortening the waveguide thereby achieving a smaller, more desirable device.
Conclusion
This prior art, made of record, but not relied upon, is considered pertinent to applicant’s disclosure since the following references have similar structure and/or use similar structure and/or similar optical elements to what is disclosed and/or claimed in the instant application:
CN 106970443 B discloses a plurality of tapered sub-portions.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DARBY M THOMASON whose telephone number is (703)756-5817. The examiner can normally be reached Mon.-Fri. 8am-5pm.
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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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/DARBY M. THOMASON/Examiner, Art Unit 2874
/UYEN CHAU N LE/Supervisory Patent Examiner, Art Unit 2874
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