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 May 15, 2026 has been fully considered and entered.
Drawings
One (1) replacement sheet of drawings was filed May 15, 2026 and has been accepted by the examiner.
Response to Arguments
Applicant's arguments filed May 15, 2026 have been fully considered but they are not persuasive.
Applicant disagrees with the rejection of claim 1, but has amended to claim 1 to require that the ramp is to increase, at an output side of the grating, a mode-overlap coupling between light at a center wavelength of each of the plurality of channels and a corresponding output waveguide of the plurality of output waveguides. Applicant submits that the cited references fail to teach or suggest this feature.
The examiner disagrees.
The examiner notes that at an output side of an arrayed waveguide grating, the wavelengths of light are imaged onto the boundary of the slab waveguide according to an interference pattern and that output waveguides are positioned at the locations of the wavelength peaks of the interference pattern where the mode-overlap coupling of the center wavelength is maximized to maximize optical coupling into the output waveguides and minimize loss, as understood by a person of ordinary skill in the art. Since the device of Oguma et al. is an arrayed waveguide grating, the output waveguides are inherently positioned at locations providing maximized mode-overlap coupling between light at a center wavelength of each of the plurality of channels.
A ramp located between input waveguides for the arrayed waveguide grating increases the light coupled into the arrayed waveguide grating by coupling additional modes of light that would have been otherwise lost in the region between the input waveguides, and therefore, also inherently increases a mode-overlap of light at the center wavelengths provided by the interference effect at the output of the second slab waveguide of the arrayed waveguide grating and coupled into the output waveguides, which are positioned at locations corresponding to the images of the center wavelengths.
Applicant argues that amended claim 1 does not merely require that the ramp increase an amount of light coupled into the grating, but rather that claim 1 requires that the ramp increase, at an output side of the grating, a mode-overlap coupling between light at a center wavelength of each channel and a corresponding output waveguide. Applicant further explains that an output-side mode-overlap coupling is not established merely by showing that more light enters the grating at the input side.
The examiner notes that Applicant has broadly claimed an auxiliary structure or ramp. Applicant has not defined any special structure or any specific structure of the ramp.
The mode-overlap of the light at the coupling regions between the output slab waveguide of an arrayed waveguide grating and the output waveguides is determined by the interference of the light within the slab waveguide that renders imaging of wavelengths of light along the output of the slab waveguide, the position of the output waveguide with respect to the imaged wavelengths of light, and the shape and size of the waveguide with respect to the shape and size of the light beams of the different wavelengths at the output of the slab waveguide. Thus, the claimed function is not simply a function of a ramp provided at the input side of the grating.
While realizing that the ramp does couple additional light into the arrayed waveguide grating, there is no indication in the claims that the ramp is anything other than a standard ramp of known prior art.
The functional recitation “ the ramp is to modify a spatial mode of light input to the grating to increase, at an output side of the grating, a mode-overlap coupling between light at a center waveguide of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides” is presumed to be inherent to the structure of the ramp. 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. The applied prior art teaches and/or suggests a ramp that is substantially identical to that of the claimed invention, 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).
The examiner notes that if the claimed structure does not possess the claimed properties or is not capable of performing the claimed functions, then the claims would be incomplete for omitting essential structural cooperative relationships of elements, such omission amounting to a gap between the necessary structural connections necessary to clearly and precisely define the invention, wherein the structure necessary to provide the claimed properties or perform the claimed functions is essential.
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.
Claims 1, 9, 11, and 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1).
Regarding claim 1; Oguma et al. discloses an apparatus (see Figure 2) comprising:
PNG
media_image1.png
528
678
media_image1.png
Greyscale
a first waveguide (first waveguide; see annotated Figure 2 above);
a first coupler (first coupler) to couple light from the first waveguide (first waveguide) into a second waveguide (second waveguide) and a third waveguide (third waveguide);
a second coupler (directional coupler 303, second coupler; see annotated Figure 2 above) to mix light in the second waveguide (second waveguide) and the third waveguide (third waveguide);
a grating (arrayed waveguide grating, AWG 302), wherein the second waveguide (second waveguide) and the third waveguide (third waveguide) are positioned as an input to the grating (302);
a plurality of output waveguides (output waveguides; see annotated Figure 2 above), wherein each of the plurality of output waveguides (output waveguides) is configured as an output to the grating (302).
Oguma et al. does not disclose one or more auxiliary structures positioned near the second waveguide and the third waveguide to modify a spatial mode of a symmetric supermode supported by the second waveguide and the third waveguide at the input to the grating, wherein the one or more auxiliary structures comprises a ramp positioned between the second waveguide and the third waveguide, wherein the ramp is to modify a spatial mode of light input to the grating to increase, at an output side of the grating, a mode-overlap coupling between light at a center wavelength of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides.
The examiner notes that at an output side of an arrayed waveguide grating, the wavelengths of light are imaged onto the boundary of the slab waveguide according to an interference pattern and that output waveguides are positioned at the locations of the wavelength peaks of the interference pattern where the mode-overlap coupling of the center wavelength is maximized to maximize optical coupling into the output waveguides and minimize loss, as understood by a person of ordinary skill in the art. Since the device of Oguma et al. is an arrayed waveguide grating, the output waveguides are inherently positioned at locations providing mode-overlap coupling between light at a center wavelength of each of the plurality of channels.
It’s generally known in the art that ramps may be placed between optical waveguides at the input and/or outputs of slab waveguide regions for the purpose of minimizing coupling loss. For example, Yamazaki (EP 1 548 471 B1) discloses that wedge-liked tapered waveguide ramps (13) are formed between arrayed waveguides (121 through 125) at a region where the waveguides are coupled to a slab waveguide (11), wherein optical signals having been propagated through the slab waveguide are incident without leakage on the connections with the arrayed waveguides to obtain low loss, and reversibly, optical signals having been propagated through the arrayed waveguides can be incident on the slab waveguide at a low loss (see paragraphs 5 and 6 of Yamazaki). Additionally, So et al. (WO 2004/061498 A1) teaches that a vertically tapered waveguide, inserted between input/output waveguides, improves insertion loss at a slab/waveguide interface of an arrayed waveguide grating structure (see the abstract and Figures 2a and 3).
Thus, before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to incorporate one or more auxiliary structures in the form of vertically tapered waveguide ramps near the second and third waveguides at the region where the second and third waveguides are coupled to the slab waveguide to modify a spatial mode of a symmetric supermode (this inherently happens due to the presence of the ramp structures) supported by the second waveguide and the third waveguide at the input of the grating for the purpose of minimizing insertion loss, wherein the one or more auxiliary structures comprises a ramp (vertically tapered ramp as taught by Yamazaki and So et al.) positioned between the second waveguide and the third waveguide, wherein the ramp is to modify a spatial mode of light input to the grating (the presence of the ramp inherently modifies the mode of light input into the grating by coupling additional light into the grating at the input) to increase, at an output side of the grating, a mode-overlap coupling between light at a center wavelength of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides (a ramp located between input waveguides for the arrayed waveguide grating increases the light coupled into the arrayed waveguide grating by coupling additional modes of light that would have been otherwise lost in the region between the input waveguides, and therefore, also inherently increases a mode-overlap of light at the center wavelengths provided by the interference effect at the output of the second slab waveguide of the arrayed waveguide grating and coupled into the output waveguides, which are positioned at locations corresponding to the images of the center wavelengths; see Figure 2 of Oguma et al. annotated above).
The functional recitation “ the ramp is to modify a spatial mode of t light input to the gratin to increase, at an output side of the grating, a mode-overlap coupling between light at a center waveguide of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides” is presumed to be inherent to the structure of the ramp. 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. The applied prior art teaches and/or suggests a ramp that is substantially identical to that of the claimed invention, 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).
Regarding claim 9; Oguma et al. discloses an apparatus comprising:
PNG
media_image2.png
528
678
media_image2.png
Greyscale
a first waveguide (first waveguide; see annotated Figure 2 above) and a second waveguide (second waveguide; see annotated Figure 2 above), the first waveguide and the second waveguide supporting at least two supermodes (see Figures 6 and 7; see paragraphs 16-18);
a slab wavelength demultiplexer (302), wherein the first waveguide (first waveguide) and the second waveguide (second waveguide) are positioned as an input to the slab wavelength demultiplexer (302);
a plurality of output waveguides (output wav3guides; see Figure 2 annotated above), wherein each of the plurality of output waveguides is configured as an output to the slab wavelength demultiplexer (302).
Oguma et al. does not disclose one or more auxiliary structures positioned near the first waveguide and the second waveguide to modify the at least two supermodes supported by the first waveguide and the second waveguide at the input to the slab wavelength demultiplexer to increase, at an output side of the slab wavelength demultiplex, a mode-overlap coupling between light at a center wavelength of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides.
The examiner notes that at an output side of an arrayed waveguide grating, the wavelengths of light are imaged onto the boundary of the slab waveguide according to an interference pattern and that output waveguides are positioned at the locations of the wavelength peaks of the interference pattern where the mode-overlap coupling of the center wavelength is maximized to maximize optical coupling into the output waveguides and minimize loss, as understood by a person of ordinary skill in the art. Since the device of Oguma et al. is an arrayed waveguide grating, the output waveguides are inherently positioned at locations providing mode-overlap coupling between light at a center wavelength of each of the plurality of channels.
Although not specifically defined in claim 9, the auxiliary structures (402 in Figure 4 of the present application) of the present invention are illustrated as a ramp placed between the waveguides. It’s generally known in the art that ramps may be placed between optical waveguides at the input and/or outputs of slab waveguide regions for the purpose of minimizing coupling loss. For example, Yamazaki (EP 1 548 471 B1) discloses that wedge-liked tapered waveguide ramps (13) are formed between arrayed waveguides (121 through 125) at a region where the waveguides are coupled to a slab waveguide (11), wherein optical signals having been propagated through the slab waveguide are incident without leakage on the connections with the arrayed waveguides to obtain low loss, and reversibly, optical signals having been propagated through the arrayed waveguides can be incident on the slab waveguide at a low loss (see paragraphs 5 and 6 of Yamazaki). Additionally, So et al. (WO 2004/061498 A1) teaches that a vertically tapered waveguide, inserted between input/output waveguides, improves insertion loss at a slab/waveguide interface of an arrayed waveguide grating structure (see the abstract and Figure 2a and 3).
Thus, before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to incorporate one or more auxiliary structures in the form of vertically tapered waveguide ramps positioned near the first waveguide and the second waveguide to modify the at least two supermodes supported by the first waveguide and the second waveguide at the input to the slab wavelength demultiplexer (this inherently happens due to the presence of the ramp structures) supported by the second waveguide and the third waveguide at the input of the grating to minimize insertion loss, thereby increasing, at an output side of the slab wavelength demultiplexer, a mode-overlap coupling between light at a center wavelength of each of a plurality of channels and a corresponding output waveguide of the plurality of output waveguides.
The functional recitation “ auxiliary structures… to increase, at an output side of the slab wavelength demultiplexer, a mode-overlap coupling between light at a center wavelength of each of the a plurality of channels and a corresponding output waveguide of the plurality of output waveguides” is presumed to be inherent to the structure of the ramp. 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. The applied prior art teaches and/or suggests a ramp as an auxiliary structure that is substantially identical to that of the claimed invention, 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).
Regarding claim 11; Oguma et al. discloses that the slab wavelength demultiplexer is an arrayed waveguide grating (AWG 302; see Figure 2).
Regarding claim 13; Oguma et al., Yamazaki, and So et al., as applied to claim 9, teach that the one or more auxiliary structures comprises a ramp positioned between the first waveguide and the second waveguide (see the rejection of claim 9 above), wherein the ramp is to increase coupling of a center wavelength of each of a plurality of channels to a corresponding output waveguide of the plurality of output waveguides (the coupling is increased by minimizing insertion loss at the interface between the first and second waveguides and the slab waveguide).
Regarding claim 14; Oguma et al. discloses a coupler (first coupler; see Figure 2 annotated above with respect to claim 9) coupled to the first waveguide (first waveguide) and the second waveguide (second waveguide), wherein the coupler (first coupler), the first waveguide, and the second waveguide form an unbalanced interferometer (MZI interferometer; see Figure 2).
Regarding claim 15; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 9 as applied above. Oguma et al. discloses an alternative embodiment, (see Figure 4 annotated below), wherein a third waveguide (third waveguides; see annotated Figure 4) is provided between the first waveguide (first waveguide) and the second waveguide (second waveguide), wherein the third waveguide (third waveguide) is evanescently coupled to the first waveguide and the second waveguide (due to the small separation distance in the area proximate the slab waveguide), wherein the first waveguide, the second waveguide, and the third waveguide support at least two supermodes. A person of ordinary skill in the art, before the effective filing date of the present invention, would have found it obvious to use the alternative demultiplexer embodiment of Oguma et al., and to provide the one or more auxiliary structures suggested by the teachings of Yamazaki and So et al. as discussed above with respect to claim 9, comprising a first auxiliary structure between the first waveguide and the third waveguide and a second auxiliary structure between the second waveguide and the third waveguide, since both Yamazaki and So et al. teach that ramps may be at each location between two waveguides.
PNG
media_image3.png
556
580
media_image3.png
Greyscale
Regarding claim 16; the first waveguide, second waveguide, and third waveguide (see annotated Figure 4 of Oguma et al. above) form a first arm, a second arm, and a third arm, respectively, of a three-arm interferometer.
Claims 4-6 are rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of Suzuki et al. (US 2006/0222296 A1).
Regarding claims 4 and 5; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 1 as applied above, but fail to disclose that each of the first waveguide, the second waveguide, and the third waveguide has a core material and a cladding material, wherein a difference in index of refraction between the core material and the cladding material is at least 0.1 over a wavelength range of the apparatus, wherein the core material is silicon nitride and the cladding material is silicon dioxide.
Silicon nitride and silicon dioxide are common materials utilized to form waveguides in silicon photonic devices. Suzuki et al. teaches a silicon photonic wavelength demultiplexer (Fig. 5) wherein the waveguide core is formed of silicon nitride and the cladding is formed of silicon dioxide and notes that the relatively high difference in refractive index between the two materials is ideal for light confinement in the waveguide (Par. 58). Suzuki further teaches this difference in refractive index is greater than 8% or roughly 0.12 (Par. 58, the examiner notes that where the refractive index of SiO2 is n = 1.5, an 8% difference is 0.12). Therefore, 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 incorporated the silicon nitride core and silicon dioxide cladding of the waveguides taught by Suzuki in the demultiplexing device disclosed by Nara/Sugita in order to achieve a difference of refractive index greater than 0.1 resulting in desired light confinement in the apparatus.
Regarding claim 6; the wavelength of light transmitted over the demultiplexer and the temperature-dependent shift are properties of the device material and structure. Oguma et al., Yamazaki, So et al., and Suzuki teach and/or suggest the apparatus comprised of silicon materials which are known to be transparent to wavelengths in the range of 1,250 and 1,370 nanometers, and having met all of the defined structural limitations, implicitly suggests an apparatus, wherein the wavelength range of the apparatus may optionally be within 1,250 and 1,370 nanometers, i.e. a person of ordinary skill in the art may choose to transmit an optical signals within this wavelength range through the apparatus, and wherein a temperature-dependent shift in center wavelength for each of a plurality of channels of the apparatus is less than one nanometer over a range of zero to eighty degrees Celsius, since temperature-dependent shift of a center wavelength is determined by the material and structural properties of the prior, all of which are addressed above.
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. 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).
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of Laming et al. (US 2004/0047560 A1).
Regarding claim 7; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 1 as applied above, but do not disclose a plurality of detectors, wherein each of the plurality of detectors is coupled to one of the plurality of output waveguides, wherein each of the plurality of output waveguides is a single mode waveguide.
Oguma et al. teaches that the apparatus (see Figure 2) is an AWG wavelength demultiplexer (see paragraph 8). Laming et al. discloses an optical power monitor for a demultiplexer (see Figure 3), wherein an AWG demultiplexer includes single mode output waveguides (33; see paragraph 26) and a plurality of detectors (24; see paragraph 25) are provided, wherein each of the plurality of detectors (24) is coupled to one of the plurality of single-mode output waveguides (33) for the purpose of monitoring the power of the demultiplexed channels and providing power control.
Thus, 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 plurality of detectors, wherein each of the plurality of detectors is coupled to one of the plurality of output waveguides, wherein each of the plurality of output waveguides is a single mode waveguide in the AWG demultiplexer of Oguma et al. for the purpose of monitoring the power of the demultiplexed channels and providing power control.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of Bulthuis (US 2012/0087667 A1).
Regarding claim 8; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 1 as applied above, wherein each of the plurality of output waveguides (output waveguides; see Figure 2 of Oguma et al., annotated above) defines a channel having a center wavelength, wherein the second waveguide (second waveguide) has a first optical path length from the first coupler (first coupler) to the second coupler (second coupler, 303), wherein the third waveguide (third waveguide) has a second optical path length from the first coupler (first coupler) to the second coupler (second coupler 303), wherein a difference between the first optical path length and the second optical path length defines a free spectral range of an interferometer formed by the first coupler, the second coupler, the second waveguide, and the third waveguide (Mach-Zehnder interferometer, MZI 304; see Figure 2 and paragraph 8), and wherein the free spectral range of the interferometer is approximately equal to a spacing (channel spacing) between center wavelengths (center wavelength λc; see paragraph 59) of adjacent channels defined by the plurality of output waveguides (this is inherent to the AWG demultiplexer structure of Oguma et al.).
Oguma et al., Yamazaki, and So et al. do not specify that a wavelength range of the apparatus is within 1,250 and 1,370 nanometers. AWGs are known to support multiple commonly used wavelength bands, including the O-band, which ranges from 1260 to 1360 nm (see Classification of Spectral Bands table on page 1 of Bulthuis). Before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to transmit any desired wavelength range over the apparatus, including a wavelength range within 1250 and 1370 nanometers, since theses wavelengths are known to be transmitted over AWG demultiplexers in the art, for the purpose of transmitting information over a desired, commonly used wavelength band of choice.
Claims 10 and 21 are rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of He et al. (US 2002/0131685 A1).
Regarding claim 10; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 9 as applied above, wherein the slab wavelength demultiplexer is a grating (arrayed waveguide grating 302, comprising two slab waveguides with an array of waveguides there-between; see Figure 2 of Oguma et al.) comprising a slab expansion region (slab waveguides), but does not disclose that the grating comprises a slab expansion region and a reflective surface. Echelle gratings, which comprising a slab expansion region and a reflective surface, are known to be used in alternative to arrayed waveguide gratings (AWGs) for the purpose of providing a folded, more compact demultiplexer. For example: He et al. teaches that arrayed waveguide gratings (see Figure 1a) and echelle gratings (see Figure 1b) are known alternative demultiplexers (see paragraph 38).
Thus, before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to use an echelle grating comprising a slab expansion region and a reflective surface in alternative to the arrayed waveguide grating (302) of Oguma et al. for the purpose of providing a more compact design and smaller footprint, since echelle gratings and arrayed waveguide gratings were known alternative demultiplexers 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).
Regarding claim 21; Oguma et al., Yamazaki, and So et al. teach and/or suggest the apparatus of claim 9 as applied above, further comprising a ramp (ramps as taught by either Yamazaki and/or So et al.; see the rejection of claim 9 above) positioned between the first waveguide and the second waveguide before the slab expansion region, wherein the ramp is to increase coupling of a center wavelength of each of a plurality of channels to a corresponding output waveguide of the plurality of output waveguides by increasing, at the ramp, an amplitude of a spatial mode of a symmetric supermode supported by the first waveguide and second waveguide (the ramps taught by Yamazaki and So et al. inherently perform this function).
Oguma et al. Yamazaki, and So et al. do not teach that the slab wavelength demultiplexer is a grating, the grating comprising a slab expansion region and a reflective surface. Oguma et al. teaches that the slab wavelength demultiplexer is a grating (arrayed waveguide grating 302, comprising two slab waveguides with an array of waveguides there-between; see Figure 2 of Oguma et al.) comprising a slab expansion region (slab waveguides). Echelle gratings, which comprising a slab expansion region and a reflective surface, are known to be used in alternative to arrayed waveguide gratings (AWGs) for the purpose of providing a folded, more compact demultiplexer. For example: He et al. teaches that arrayed waveguide gratings (see Figure 1a) and echelle gratings (see Figure 1b) are known alternative demultiplexers (see paragraph 38).
Thus, before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to use an echelle grating comprising a slab expansion region and a reflective surface in alternative to the arrayed waveguide grating (302) of Oguma et al. for the purpose of providing a more compact design and smaller footprint, since echelle gratings and arrayed waveguide gratings were known alternative demultiplexers 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).
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of Park et al. (US 2015/0078708 A1).
Regarding claim 12; Oguma et al., Yamazaki, and So et al. teaches and/or suggest the apparatus of claim 9 as applied above, wherein one or more auxiliary structures are positioned between the first waveguide and the second waveguide, wherein the auxiliary structures increase coupling of a center wavelength of each of a plurality of channels to a corresponding output waveguide of the plurality of output waveguides, but does not disclose that the one or more auxiliary structures comprises a block with a flat top. Park et al. discloses alternative auxiliary structures (see annotated Figure 9A below) comprising a block with flat surfaces between waveguides (waveguides 114 separated by trenches 115; see Figure 9A) at the region where the waveguides are coupled to a slab waveguide (coupler slab 112).
PNG
media_image4.png
385
476
media_image4.png
Greyscale
Therefore, before the effective filing date of the present invention, a person of ordinary skill in the art would have found it obvious to incorporate auxiliary structure comprising a block with flat surfaces between the waveguides in alternative to the ramp auxiliary structures for the purpose of obtaining desired optical coupling results, since this was a known alterative auxiliary structure of 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).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and in further view of Kato et al. (US 2001/0012424 A1).
Regarding claim 17; Oguma et al., Yamazaki, and So et al. teaches and/or suggest the apparatus of claim 9 as applied above, but fail to teach that each of the first waveguide and the second waveguide has a core material and a cladding material, wherein the core material is germanium-doped silica and the cladding material is silicon dioxide. Optical waveguide cores are routinely made of Germanium-dope silica and cladding is routinely made of silicon dioxide in the art, wherein the selection of these respective materials for core and cladding materials provides a relative refractive index difference allowing for light to be confined within the core. For example, Kato et al. (see Figures 4-6) teaches that AWG optical multiplexer/demultiplexer devices may include cladding (22, 24, 31b, 31d) and a core (23, 32c), wherein the cladding may be comprised of silicon dioxide (see paragraphs 58 and 73) and the core may comprise of (germanium-doped silicon dioxide, i.e. germanium doped silica; see paragraphs 59 and 74).
Thus, before the effective filing date of the present invention, a person would have found it obvious to form the device of Oguma et al., wherein each of the first waveguide and the second waveguide has a core material and a cladding material, wherein the core material is germanium-doped silica and the cladding material is silicon dioxide, since these materials are known to be used to form claddings and cores in the art, and since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use. In re Leshin, 125 USPQ 416.
Claims 18 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Oguma et al. (US 2022/0269001 A1) in view of Yamazaki (EP 1 548 471 B1) and So et al. (WO 2004/061498 A1), and further in view of Bulthuis et al. (US 2003/0063858 A1) and Lee et al. (US 2004/0042752 A1).
Regarding claims 18 and 20; As applied to claim 1 above, Oguma et al. (see Figure 2, annotated below), Yamazaki, and So et al. teach and/or suggest a method for forming an apparatus, the method comprising:
PNG
media_image1.png
528
678
media_image1.png
Greyscale
forming, on a cladding layer (the cladding layer inherently surrounds the waveguide core),
a first waveguide (first waveguide; see annotated Figure 2 above),
a second waveguide (second waveguide), a
third waveguide (third waveguide),
a first coupler (first coupler),
a second coupler (second coupler, 303),
a grating (arrayed waveguide grating 302), and
a plurality of output waveguides (output waveguides); and
forming one or more auxiliary structures (ramps as taught by Yamazaki and/or So et al.; see the rejection of claim 1 above) positioned near the second waveguide and the third waveguide to modify supermodes supported by the second waveguide and the third waveguide at an input to the grating (the presence of ramps at the junction of the waveguides and the slab waveguide inherently performs this function) to increase, at an output side of the grating, a mode-overlap coupling between light at a center wavelength of each of the a plurality of channels and a corresponding output waveguide of the plurality of output waveguides (this is an inherently result of the provision of the ramp at the input side as discussed above with respect to claims 1 and 9),
wherein the first coupler (first coupler; see Figure 2 annotated above) is to couple light from the first waveguide (first waveguide) into the second waveguide (second waveguide) and the third waveguide (third waveguide),
wherein each of the second waveguide and the third waveguide is connected to the first coupler (first coupler) and the second coupler (second coupler 303),
wherein the second waveguide and the third waveguide are positioned as an input to the grating (arrayed waveguide grating 302; see Figure 2 annotated above), and
wherein each of the plurality of output waveguides (output waveguides) is configured as an output to the grating (302);
wherein the one or more auxiliary structures (ramps suggested by the teachings of Yamazaki and/or So et al.) comprises a ramp positioned between the second waveguide and the third waveguide, wherein the ramp is to increase coupling of a center wavelength of each of a plurality of channels to a corresponding output waveguide of the plurality of output waveguides (this is an inherent function of a ramp at the junction between the waveguides and the slab waveguide),
Oguma et al., Yamazaki, and So et al. do not disclose that forming steps require photolithography, wherein photolithographically forming the ramp comprising photolithographically forming the ramp with use of grayscale photolithography.
Bulthuis et al. teaches that transmission waveguides and slab waveguides are typically formed with standard photolithographic techniques (see paragraph 5). Lee et al. teaches that waveguides, slab waveguides, and ramps (440; see Figure 4F) are made by lithographic processes (see paragraph 33) with the use of a gray scale mask (see paragraph 35) to form the ramps (vertical taper). Thus, 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 waveguides and slab waveguides with standard photolithography processes and to form the ramps with a gray scale photolithography process for the purpose of using standard techniques known to form similar elements in the art.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
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.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/MICHELLE R CONNELLY/Primary Examiner, Art Unit 2874
Prosecution Insights