DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The prior art documents submitted by applicant in the Information Disclosure Statements filed on July 8, 2024 and July 16, 2024 have all been considered and made of record (note the attached copies of form PTO-1449).
Drawings
Twenty-eight (28) sheets of drawings were filed on July 08, 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.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 4, 15, 17, and 19 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
The claims are generally narrative and indefinite, failing to conform with current U.S. practice. They appear to be a literal translation into English from a foreign document and are replete with grammatical and idiomatic errors.
Regarding claim 4; Claim 4 recites the limitation “each of the unit diffraction grating include a combination of periodic structures of diffraction gratings which the output part has”. This limitation renders claim 4 indefinite. As understood by the examiner, the “unit diffraction gratings” are the same as “diffraction gratings which the output part has”. The examiner also notes that all diffraction gratings have periodic structures by definition. It is unclear which “periodic structures” the unit diffraction gratings are required to include in claim 4.
Regarding claim 15; Claim 15 recites “a plurality of diffraction grating groups” for both the extension part and the output part due to dependency on claim 1. It is not clear which diffraction grating groups are being referred to by the further limitations of claim 15. If the limitations of claim 15 refer to the diffraction grating groups of the extension part it is unclear which directions are “inwardly with respect to the output part” and “outward from the output part” from the perspective of the extension part. Examiner requests clarification. For examination purposes, the limitations “a diffraction grating configured to diffract the light outward from the output part” and “a diffraction grating configured to diffract the light inwardly with the respect to the output part” will be interpreted to be referring to the diffraction grating groups of the output part as claimed in claim 1.
Regarding claim 17; the claim recites the limitation “the plurality of diffraction grating groups have a smaller spacing than the observer’s pupil diameter”. The term “observer’s pupil diameter” is relative term that is not well defined. The specification states that “The pupil diameter varies from person to person and depends on the brightness of the surrounding environment and generally varies from about 2.0 mm to about 8.0 mm” (see paragraph 174). The specification then says “[i]n particular, a pupil diameter of 3.0 mm is generally assumed in the design of light guide plates for AR. Therefore, when the light guide plate according to the embodiment of the present technology is used for AR, the spacing G of the plurality of diffraction grating groups 5 is preferably 3.0 mm or less” (see paragraph 174). Thus, the particular range of values that may fall within “an observer’s pupil diameter” varies depending on the observer and the brightness of the surrounding environment and it’s unclear what values Applicant is intending to claim. If a pupil diameter of 3.0 mm is assumed then claim 17 is a substantial duplicate of claim 18. If a different pupil diameter is required for claim 17 it should be explicitly stated. Appropriate correction is required.
Regarding claim 19; Claim 19 recites the limitation “the transition region has a diffraction efficiency which is between a diffraction efficiency in an approximate center of the diffraction grating group and a diffraction efficiency in an approximate center of a diffraction grating group adjacent to the diffraction grating group”. This limitation is confusing and does not differentiate between diffraction grating groups. The examiner suggests rewriting this limitation to identify a first diffraction grating with a first diffraction efficiency and a second diffraction grating with a second diffraction efficiency that are adjacent to each other. For examination purposes, the claim will be interpreted as “the transition region has a diffraction efficiency which is between a first diffraction efficiency in an approximate center of a first diffraction grating group and a second diffraction efficiency in an approximate center of a second diffraction grating group where the first and second diffraction grating groups are adjacent”.
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.
Claim(s) 1-2, 8-10, 12-16, and 20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Valera et al. (WO 2020217044 A1), hereafter Valera.
Regarding claim 1; Valera teaches (see Figure 5) a light guide plate (106), comprising:
an incident part (input diffraction grating 101; Page 9, lines 1-2) configured to diffract incident light into the light guide plate;
a path configured to guide the light diffracted into the light guide plate by the incident part by internal total reflection (Page 9, lines 2-5); and
an output part (104,112) configured to diffract the light guided by the path and output the light toward an observer's pupil (104; Page 9, lines 10-13),
the output part (104,112) having a plurality of diffraction grating groups (104, 112) in two-dimensional arrangement (see Figure 4),
the plurality of diffraction grating groups (104, 112) including, in front view,
at least one of a diffraction grating configured to diffract the light outward from the output part (104),
a diffraction grating configured to diffract the light inwardly with respect to the output part (112; Page 9, lines 9-10), and
a diffraction grating configured to diffract the light toward the observer's pupil (104).
Regarding claim 2; Valera teaches the light guide plate according to claim 1. Valera further teaches (see Figure 6):
wherein each of the diffraction grating diffracts the light in a two-dimensional direction (see grating vectors 114, 111, and 122),
the sum of a lattice vector which the incident part has (111) and a basic lattice vector which the output part has (114) is closed (Examiner is interpreting that “closed” in this context means that the vectors sum to zero. Valera teaches in Page 9, lines 29-32, “The grating vectors 111, 114 are equal in magnitude. In this first group of optical paths the grating vectors 111, 114 are opposite in direction since the optical path involves a positive (+1) diffraction order followed by a negative (-1) diffraction order. As such, the resultant vector has substantially zero magnitude”.), and
the diffraction grating groups arranged adjacent to each other (see Figure 5, 101, 104 and 112 are adjacent) have lattice vectors substantially in the same direction (See Figure 6, grating vectors 111 and 114 are in substantially the same direction).
Regarding claim 8; Valera teaches the light guide plate according to claim 1. Valera further teaches (see Figure 7-8) wherein the diffraction grating group has a return diffraction grating (212) configured to diffract the light inwardly with respect to the output part (Page 11, lines 8-10), and the return diffraction grating has a pitch which is a value obtained by dividing, by an integer, the pitch of other diffraction gratings which the output part has (Valera teaches in Page 14, lines 1-5, “the pitch of the grooves in the return grating 212 is half that of the output grating 204”).
Regarding claim 9; Valera teaches the light guide plate according to claim 8. Valera further teaches (see Figure 5) wherein the diffraction grating group (101, 104, and 112) including the return diffraction grating (112) is provided outside of a region on which light from the path is incident and in an outer periphery of the output part (104 and 112 are outside the waveguide 106).
Regarding claim 10; Valera teaches the light guide plate according to claim 8. Valera further teaches (see Figure 4) wherein the return diffraction grating (112) has a stripe-like periodic structure (notice the grooves on Figure 4).
Regarding claim 12; Valera teaches the light guide plate according to claim 1. Valera further teaches (see Figure 5) wherein the output part is provided on one or both surfaces of the light guide plate (in Figure 5 elements 104 and 112 are on one surface of the waveguide 106).
Regarding claim 13; Valera teaches the light guide plate according to claim 1. Valera further teaches wherein the output part (104 and 112) is provided in a location which is the same as or different from the incident part (101) in a thickness-wise direction of the light guide plate.
Regarding claim 14; Valera teaches the light guide plate according to claim 1. Valera further teaches comprising one or more of the incident parts (101), and one or more of the output parts (104 and 112).
Regarding claim 15-16; Valera teaches the light guide plate according to claim 1. Valera further teaches:
comprising an extension part between the incident part and the output part (“there may be an intermediate diffractive optical element positioned in or on the waveguide between the input diffractive optical element and the output diffractive optical element” Valera Page 3, lines 12-14),
wherein the extension part has a plurality of diffraction grating groups (104, 112) in a two-dimensional arrangement (the extension part diffractive optical element must, by definition, have a plurality of diffraction grating groups in a two-dimensional arrangement, even if the groups are identical in composition, as a diffraction grating group is simply a plurality of unit diffraction gratings (grooves, as defined by applicant in the specification (Figure 3)),
the plurality of diffraction grating groups (104, 112) include, in front view,
at least one of a diffraction grating configured to diffract the light outward from the output part (Valera Figure 5, element 104),
a diffraction grating configured to diffract the light inwardly with the respect to the output part (112), and
a diffraction grating configured to diffract the light toward the output part (Page 3, lines 15-17).
wherein the extension part and the output part are arranged adjacent to each other (the intermediate diffractive element is between the input and the output; therefore, they must be adjacent, see Figure 5, the intermediate diffractive element would be placed between elements 101 and 104).
Regarding claim 20; Valera further teaches an image display device (see Figure 5) comprising the light guide plate according to claim 1 (see rejection above), and an image forming unit (102) that outputs image light to the light guide plate.
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.
Claim(s) 3-7 and 17-18 are rejected under 35 U.S.C. 103 as being unpatentable over Valera as applied to claim 1 above, and in further view of Blomstedt (US 2021/0165142 A1).
Regarding claims 3-7; Valera teaches the light guide plate according to claim 1. Valera does not explicitly teach a light guide plate wherein the diffraction grating groups has a plurality of unit diffraction gratings in a two-dimensional arrangement, each of the unit diffraction grating include a combination of periodic structures of diffraction gratings which the output part has, each of the unit diffraction grating has a shape which substantially continuously changes from one side to the other in a plane of the output part, the diffraction grating groups have different shapes according to locations in a plane of the output part, nor each of the unit diffraction grating have different shapes according to locations in a plane of the output part. However, in the same field of endeavor, Blomstedt teaches (see Figure 5) a light guide device (title, abstract)
wherein the diffraction grating groups (56A; Paragraph [0071]) has a plurality of unit diffraction gratings (the grating pattern inside the group constitute the unit diffraction gratings) in a two-dimensional arrangement (Paragraph [0071]).
wherein each of the unit diffraction grating include a combination of periodic structures of diffraction gratings which the output part has (it can be seen in Figure 5 that the different grating groups (56A) have different grating patterns (Paragraph [0071])).
wherein each of the unit diffraction grating has a shape which substantially continuously changes from one side to the other in a plane of the output part (see the change in grating patterns across Figure 5).
wherein the diffraction grating groups (56A) have different shapes according to locations in a plane of the output part (Figure 5 depicts the groups (56A) having irregular shapes).
wherein each of the unit diffraction grating have different shapes according to locations in a plane of the output part (see the change in grating patterns across Figure 5).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to modify the light guide plate taught by Valera with the diffraction grating group shapes and unit diffraction gratings taught by Blomstedt with a reasonable expectation of success. One of ordinary skill in the art would have been motivated to make this modification because Blomstedt teaches “The invention is based on forming the out-coupling region of a diffractive element from a plurality of sub-regions that have at least partly different doubly periodic grating patterns. This provides new freedoms for design for out-coupling of light in optical devices, and in particular increasing the size of out-coupling regions and the achievable FOV. In particular, the sub-regions may have the same internal periods at the same angles with respect to each other and also with respect to the waveguide, but different microstructure of their elementary grating features. This allows for exit pupil expansion to take place within the out-coupling region, whereby no separate exit pupil expansion regions are needed” (Blomstedt Paragraph [0010]).
Regarding claims 17-18; Valera teaches the light guide plate according to claim 1. Valera and Blomstedt are silent on the explicit spacing of the diffraction grating groups. However, Blomstedt suggests (see Figure 2) the relative size of the entire out-coupling region (16) compared to the observer’s pupil (18). Therefore, Blomstedt suggests (see Figure 5) that the spacing of the diffraction grating groups (sub-regions 56A) in the out-coupling region (56) are of similar proportions to the diameter of the observer’s pupil (18). It is known in the art that the observer’s pupil diameter is approximately 3.0 mm, as evidenced by applicant’s specification, paragraph [0111] (“In particular, a pupil diameter of 3.0 mm is generally assumed in the design of light guide plates used for AR”). Therefore, Blomstedt suggests a spacing of the diffraction grating groups on the order of 3.0 mm. Thus, a person of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to choose the spacing between the diffraction grating groups to have a smaller spacing than the observer’s pupil diameter or have a spacing of 3.0 mm or less in order to improve image quality. See MPEP 2144.05(I).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Valera and Blomstedt as applied to claim 3 above, and in further view of Koshitouge et al. (KR 20150136504 A), hereafter Koshitouge.
Regarding claim 11; Valera and Blomstedt teach the light guide plate according to claim 3. Valera and Blomstedt do not explicitly teach wherein each of the unit diffraction grating has a hole pattern or a pillar pattern. However, in the same field of endeavor, Koshitouge teaches (see Figure 1) a light guide plate (14) with unit diffraction grating dimensional patterns including hole type and pillar types (Paragraph [0093] in translated document). Therefore, a person of ordinary skill in the art, before the effective filing date of the claimed invention, would have found it obvious to construct the unit diffraction grating elements of Valera and Blomstedt with any desired pattern that was previously known in the diffraction grating art, including the hole patterns or pillar patterns taught by Koshitouge, 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 19 is rejected under 35 U.S.C. 103 as being unpatentable over Valera as applied to claim 1 above, and in further view of Wildnauer (US 2006/0056028 A1).
Regarding claim 19; Valera teaches the light guide plate according to claim 1, but does not teach wherein at least one of the diffraction grating groups has a transition region at an end thereof, and the transition region has a diffraction efficiency which is between a diffraction efficiency in an approximate center of the diffraction grating group and a diffraction efficiency in an approximate center of a diffraction grating group adjacent to the diffraction grating group. However, in the same field of endeavor, Wildnauer teaches (see Figure 6A and 6B; Paragraph [0059-0066]) a diffraction grating (200) wherein at least one of the diffraction grating groups (340, 342, 344, 346, 347) has a transition region at an end thereof (see the concentric circles between the successive regions), and the transition region has a diffraction efficiency which is between a diffraction efficiency in an approximate center of the diffraction grating group and a diffraction efficiency in an approximate center of a diffraction grating group adjacent to the diffraction grating group (see the diffraction efficiency function 348). Necessarily, the diffraction efficiency of the transition regions (boundaries) falls between the diffraction efficiencies at the centers of the adjacent regions, as seen by the step function (348). Furthermore, Wildnauer teaches that increasing the number of regions (diffraction grating groups) will result in a smoothing of the diffraction efficiency function (Paragraph [0063]). It would have been obvious for one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the light guide plate taught by Valera with diffraction gratings that follow the diffraction grating efficiency functions described by Wildnauer. One of ordinary skill in the art would have been motivated to make this modification because Wildnauer teaches “Spatially varying the diffraction efficiency of the grating may be accomplished by selectively changing or modifying one or more grating design parameters such as the shape, size, depth, profile, pitch, and optical properties of the diffraction grooves at predetermined locations on the grating” (Abstract). One of ordinary skill in the art would be further motivated to ensure the diffraction efficiency across the diffraction grating follows a smooth, continuous curve without discontinuities in order to properly redirect the light and improve image quality.
Conclusion
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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