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 .
Remark
This Office Action is in response to applicant’s amendment filed on August 24, 2026, which has been entered into the file.
By this amendment, the applicant has amended claims 1, 12-16, and 18-19 and has newly added claim 20.
Claims 1-20 remain pending in this application.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 8-13 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the enablement requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention.
In light of the amended phrase of “the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer” recites in claim 1 (base claim), it is therefore impossible at the same time that “the residual thickness becomes greater toward substantially a center of the emission portion from the incidence portion” as recited in claim 8.
Furthermore, claim 10 recites the phrase “height of the diffraction grating becomes higher toward substantially the center of the emission portion from the incidence portion” that is not explicitly supported and enable by the specification. Specifically, in light of the amended phrase of “the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer” as recited in claim 1 and the recited phrase in claim 8 “the residual thickness becomes greater toward substantially a center of the emission portion from the incidence portion”, the specification fails to give positive support for the height of the diffraction grating to become higher toward the center of the emission portion from the incidence portion.
The specification and claims fail to provide the enablement of the equation claimed in the amended claims 12 and 13. Specifically in light of the amendment to claim 1, “the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer”, if the thickness of the residual layer is not constant, then the thickness ( Dt) is referred to thickness of the residual layer at which point?
The equation recited in claims 12 and 13 therefore cannot be enabled by the specification of originally filed.
Clarification and correction are required.
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 8-11 and 19-20 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.
In light of the amended phrase of “the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer” recites in claim 1 (base claim), the scopes of claim 8 are confusing and indefinite since it is impossible for the “the residual thickness becomes greater toward substantially a center of the emission portion from the incidence portion”.
Claims 9-11 inherit the rejection from is based claim (claim 8).
The phrase “wherein the residual layer thickness becomes continuously smaller as distance from the incidence portion becomes longer” recited in claim 19 has been repeated, that makes the scopes unclear.
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, 4-8, 10-14 and 16-18 is/are rejected under 35 U.S.C. 103 as being unpatentable over US patent application publication by Yang et al (US 2019/0137777 A1).
Claim 1 has been amended to necessitate the new grounds of rejection.
Yang et al teaches, with regard to claim 1, a light guide plate, (100, please see Figures 1A and 1B) that is comprised of an incoupling grating (107, Figure 1A) serves as the incidence portion that diffracts incident light into the light guide, a substrate (eyepiece or imprinted substrate 100) that internally totally reflects the light diffracted into the light guide plate or the substrate by incidence portion and guides the light, an exit pupil expander (EPE, 109) that serves as the emission portion that diffracts the light guided by the substrate and emits the light to a pupil of an observer (102). Yang et al teaches that the emission portion or the exit pupil expander (EPE) includes a diffraction grating (please see paragraph [0041]). As shown in Figure 1B, Yang et al teaches that the grating has a residual layer, (please see Figures 1B and 6A, paragraph [0063]), with a residual layer thickness formed between the diffraction grating and the substrate.
This reference has met all the limitations of the claims. It however does not teach explicitly that the residual layer thickness is determined such that a light intensity of the light emitted from the emission portion is uniform. Yang et al does teach that the residual layer thickness is varied across the grating which provide different diffraction properties and different diffraction efficiency across the grating, (please see Figure 1B). It would then have been obvious to one skilled in the art to apply the teachings of Yang et al to modify the residual layer thickness of the diffraction grating of emission portion to allow the intensity of the light emitted from the emission portion be made uniform.
Claim 1 has been amended to include the phrase substrate configured to receive light diffracted by the incidence portion and to guide the light by total internal reflection within the substrate”.
Yang et al teaches the substrate (eyepiece or imprinted substrate 100) configured to receive light diffracted by the incidence portion (107, Figure 1A) and to guide the light by total internal reflection within the substrate.
Claim 1 has been amended to include the phrase “the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer”.
Yang et al teaches that the diffraction grating such as the EPE (109) may have the residual layer thickness becomes continuously smaller as a distance from the incidence portion becomes longer, (please see Figure 1B, paragraphs, [0042]).
With regard to claims 4 and 5, Yang et al teaches that the diffraction grating has a varied residual layer thickness, (please see Figure 1B) which means the grating has a varied grating height that may be made higher toward center of the emission portion from the incidence portion, for the purposed of providing different diffraction properties and efficiency across the diffraction grating. It is within general level of skill to modify the grating height of the diffraction grating for the purpose of achieving uniform light intensity for the light emitted from the emission portion.
With regard to claims 6 and 7, Yang et al teaches that the residual layer thickness becomes smaller as a height of the diffraction grating becomes higher, (please see Figure 1B). Furthermore, it would have been obvious to one skilled in the art to design the diffraction grating with the residual layer thickness and the diffraction grating height profiles as shown in the Figure 1B to be disposed in a manner that the smaller residual layer thickness and the higher diffraction grating height be placed at the center of the emission portion and the greater residual layer thickness and the lower diffraction grating be disposed at the incidence portion for the benefit of modulating the emitted light with desired intensity and profile.
With regard to claims 8, 10 and 11, claims are rejected under 35 USC 112, first and second paragraphs rejections for the reasons set forth above. They can only be examined in the broadest interpretation.
Yang et al teaches that the residual layer thickness becomes smaller as a height of the diffraction grating becomes higher, (please see Figure 1B). Furthermore, it would have been obvious to one skilled in the art to design the diffraction grating with the residual layer thickness to become greater from the incidence portion toward the center of the emission portion. As for claim 10, it is rejected under 35 USC 112, first paragraph for the reasons set forth above. It can only be examined broadly. It is obvious to one skilled in the art to design a diffraction grating with both residual layer thickness and the grating height be varied in the same manner to have the grating height also become greater toward the center of the emission portion for the benefit of allowing the diffraction grating to have desired properties. With regard to claim 11, it is within general level skilled in the art to make the residual layer thickness become smaller toward a side opposite to the incidence portion from the center of the emission portion as an obvious matters of design choice to one skilled in the art to make the diffraction grating with desired the property.
With regard to claims 12 and 13, these claims are rejected under 35 USC 112, first paragraph, for the reasons set forth above. These claims can only be examined in the broadest interpretation. It is known in the optics theory that optical path length difference between lights reflected from different points of the diffraction grating to achieve constructive interference the following relationship should hold: Dt = (l/(4n*cos(b)), with Dt being the thickness of the diffraction grating, n being the refractive index of the grating, l being the wavelength of light incident and b being the angle of incidence. Makes the residual layer thickness Dt less than the (l/(4n*cos(b)) would ensure the light path difference due to the residual layer would not contribute to constructive interference in order to reduce the noise interference from the residual layer.
With regard to claim 14, Yang et al teaches that the light guide plate further comprise an orthogonal pupil expander (108, Figure 1A) to serve as the expansion portion that includes a diffraction grating (please see paragraph [0037]) to diffract the light guided by the substrate toward the emission portion and expands the light, (please see Figure 1A). In light of Figure 1B, it is either implicitly true or obvious to one skilled in the art to make the diffraction grating of the expansion portion to also have a residual layer with a thickness that is formed between the diffraction grating and the substrate and is to be determined and modulated so that the intensity of the light is modified so that when it is emitted from the emission portion it has a uniform intensity.
With regard to claim 16, Yang et al teaches that the incidence portion or incoupling grating (107, Figure 1A) also includes a diffraction grating. In light of Figure 1B, it is either implicitly true or obvious to one skilled in the art to make the diffraction grating of the incidence portion to also have a residual layer with a thickness that is formed between the diffraction grating and the substrate and is to be determined and modulated so that the intensity of the light is being modified so that when it is emitted from the emission portion it has a uniform intensity.
With regard to claim 17, Yang et al teaches that the emission portion (109, Figure 1A) is disposed one at least one surface of the light guide.
With regard to claim 18, Yang et al teaches that the light guide comprises one incidence portion (107, Figure 1A) and one emission portion (109).
Claim(s) 2, 3, and 9 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al as applied to claims 1 above, and further in view of the US patent issued to Calafiore et al (PN. 10,823,887).
The light guide plate taught by Yang et al as described in claim 1 above has met all the limitations of the claims.
With regard to claims 2, 3, and 9, the diffractive grating taught by Yang et al has a refractive index and it is within general level knowledge in the art that the refractive index of the diffraction grating determines the diffraction property of the diffraction grating. Calafiore et al in the same field of endeavor teaches a diffraction grating wherein the refractive index of the diffraction grating may vary across the diffraction grating, (please see Figures 13 and 16). It is therefore obvious to one skilled in the art to apply the teachings of Calafiore et al to vary the refractive index of the diffraction grating across the grating for the benefit of modulating the diffraction efficiency of the diffraction grating for the benefit of allowing the intensity of the light emitted may have a uniform intensity. It is within general level skilled in the art to make the refractive index of the diffraction grating to become higher from the incidence portion toward the center of the emission portion for the benefit of allowing the diffraction grating has the desired property.
Claim(s) 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Yang et al as applied to claims 1 above, and further in view of the US patent application publication by Olkkonen et al (US 2021/0215942 A1).
The light guide plate taught by Yang et al as described in claim 1 above has met all the limitations of the claims.
With regard to claim 15, this reference does not teach explicitly to include a return portion that diffracts the light inward of the emission portion. Olkkonen et al in the same field of endeavor teaches a light guide plate having an incidence grating portion (520D, Figure 5D, paragraph [0049]) and an emission grating portion (560D) wherein a grating mirror (531D, 532D, 533D or 534D) serves as the return portion for diffracting the light inward of the emission portion (560D). The grating mirror or the return portion is disposed on the outer side of a region on which light from the substrate is incident and an outer periphery of the emission portion, (please see Figure 5D). The return portion is a grating mirror that comprises a diffraction grating. In light of Figure 1B of Yang et al, it is either implicitly true or obvious to one skilled in the art to make the diffraction grating of the return portion to also have a residual layer with a thickness that is formed between the diffraction grating and the substrate and is to be determined and modulated so that the intensity of the light is being modified so that when it is emitted from the emission portion it has a uniform intensity.
Claim(s) 19 and 20 is/are rejected under 35 U.S.C. 103 as being unpatentable over the US patent application publication by Yang et al (US 2019/0137777 A1).
Claim 19 has been amended and claim 20 has been newly added to necessitate the new grounds of rejection.
Yang et al teaches, with regard to claim 19, an image display device that is comprised of a light guide plate, (100, please see Figures 1A and 1B) comprises an incoupling grating (107, Figure 1A) serves as the incidence portion configured to diffracts incident light into the light guide plate, a substrate (eyepiece or imprinted substrate 100) configured to receive the light diffracted by the incidence portion and to guide the light by total internal reflection within the substrate, and an exit pupil expander (EPE, 109) that serves as the emission portion configured to diffract the light guided by the substrate and to emit the light to a pupil of an observer (102).
Yang et al teaches that the emission portion or the exit pupil expander (EPE) includes a diffraction grating (please see paragraph [0041]). As shown in Figure 1B, Yang et al teaches that the grating has a residual layer, (please see Figures 1B and 6A, paragraph [0063]), with a residual layer thickness that is formed between the diffraction grating of the emission portion and the substrate.
Yang et al teaches that the residual layer has a thickness becomes continuously smaller as a distance from the incidence portion becomes longer, (please see Figure 1B). Yang et al teaches that the varying depth of the diffraction grating which referred to the varying thickness of the residual layer would improve the intensity of the light outcoupled by the emission portion and would characterize to increase the uniformity of the intensity of the light, (please see paragraph [0042]). This means the thickness of the residual layer would be a factor or be determined to increase the uniformity of the light intensity outcoupled by the emission portion.
Yang et al further teaches the image display device, (please see 1A, paragraph [0004]) includes an image information unit (LCOS SLM (103)) that emits image light to the light guide plate, (please see Figure 1A).
With regard to claim 20, Yang et al teaches that the residual layer has a thickness becomes continuously smaller as a distance from the incidence portion becomes longer, (please see Figure 1B), which includes toward the center of the emission portion from the incidence portion.
Response to Arguments
Applicant's arguments filed on August 24, 2026 have been fully considered but they are not persuasive. The newly amended claims and newly added claim have been fully considered and they are rejected for the reasons set forth above.
In response to applicant’s argument concerning the thickness of the residual layer to be determined such that a light intensity of the light emitted from the emission portion is uniform, the applicant being one skilled in the art must have the basic knowledge that the varying depth of the diffractive grating, as shown by Figure 1B of Yang et al, would change the diffraction efficiency of the diffraction grating and diffraction efficiency is directly defined by the intensity of the light emitted from the emission portion. This implicitly means that the thickness of the residual layer or the depth of the diffraction grating is determined to make the intensity of the light be uniform. Yang et al also teaches that the varying depth of the diffraction grating would be characterized by increased uniformity of the light intensity to improve the user’s experience, (please see paragraph [0042]).
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 AUDREY Y CHANG whose telephone number is (571)272-2309. The examiner can normally be reached M-TH 9:00AM-4:30PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Stephone B Allen can be reached at 571-272-2434. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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AUDREY Y. CHANG
Primary Examiner
Art Unit 2872
/AUDREY Y CHANG/Primary Examiner, Art Unit 2872
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