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
The amendments to the claims, in the submission dated 01/28/2026, are acknowledged and accepted. No claims are amended. No claims are cancelled by the applicant. No new claims are added. Claims 1-11 are pending.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Lu US PGPub 2005/0122599 A1 (of record, see IDS dated 11/01/2023, hereinafter, “Lu”) in view of Yamashita et al. US PGPub 2008/0130128 A1 (of record, see Office action dated 10/30/2025, hereinafter, “Yamashita”) and Lohmann, Adolf W. "Scaling laws for lens systems." Applied Optics 28.23 (1989): 4996-4998 (of record, see Office action dated 10/30/2025, hereinafter, “Lohmann”).
Regarding independent claim 1, Lu discloses a projection lens group configured to project light (see title and abstract describing a projection lens and display system), comprising:
a first lens group (Fig. 2 depicts an exemplary embodiment of the wide-angle projection lens, which includes three lens groups, refer to pars. [0015] and [0028], one of which can be labeled a first lens group); and
a second lens group (Fig. 2 depicts an exemplary embodiment of the wide-angle projection lens, which includes three lens groups, refer to pars. [0015] and [0028], one of which can be labeled a second lens group),
wherein the first lens group and the second lens group are sequentially arranged in a propagation direction of the light (Fig. 2 shows rays passing through the projection lens sequentially, therefore the lens groups of Lu are arranged sequentially in a propagation direction of the light), the first lens group has a positive focal length (Fig. 2, the first lens group counting from the propagation direction of light is the third lens group G3, which has positive refractive power, par. [0028]), the second lens group has a negative focal length (Fig. 2, the second lens group counting from the propagation direction of light is the second lens group G2, which can have negative refractive power, par. [0028]), and an aperture stop is arranged between the first lens group and the second lens group (the aperture stop of the projection lens lies within or near the second lens group, par. [0026], and refer to Table 2 where the aperture stop is positioned at surface 8, and in Table 3 surface 8 is between the first lens group equivalent and the second lens group equivalent).
However, Lu does not disclose wherein the focal length of the first lens group denoted by f1 and the focal length of the second lens group denoted by f2 satisfy: 120.0 mm < f1 < 128.0 mm, and -47.0 mm < f2 < -40.0 mm (the first lens group equivalent is third lens group G3 which has a focal length of 22.863 as determined from the parameters provided in Table 3, and the second lens group equivalent is the second lens group G2 which has a focal length of -730.518 as determined from parameters in Table 3).
In the same field of invention, Yamashita discloses a lens optical system with a first lens group (see Yamashita Fig. 4 depicting Example 2 with three lens elements, where lens element 1a is equivalent to a first lens group, refer to at least Table 1 and pars. [0081-83] thereof), a second lens group (Fig. 4 of Yamashita, Example 2 has a second lens element, par. [0081] that is equivalent to a second lens group), wherein the first lens group and the second lens group are sequentially arranged in a propagation direction of the light (Fig. 4, the lens groups are arranged sequentially in the propagation direction of light), a lens group has a positive focal length (Fig. 4, the second lens element of the first lens group equivalent has a positive focal length as determined from the parameters for Example 2 provided in Table 1), a lens group has a negative focal length (Fig. 4, the first lens element has a negative focal length as determined from the parameters for Example 2 provided in Table 1), and an aperture stop (Fig. 4, Example 2 has an aperture stop S in contact with surface R5 of lens 3, par. [0081]). The lens group equivalents of Yamashita have focal lengths f1 = -2.12, f2 = 6.02, and f3 = 1.52 as provided in Table 11 thereof. These lens elements have a ratio of focal lengths of f2/f1 = 6.02/(-2.12) or -2.88. The Examiner notes that the instant application does not claim a focal length ratio explicitly, but the claimed ranges for f1 and f2 implicitly span a range f2/f1 from -3.2 to -2.55. Yamashita teaches an optical device with lens groups having a focal length ratio of -2.88, within the range of the instant application’s implicit range.
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 modified the device disclosed by Lu by adjusting the radiuses of curvature and the indices of refraction to arrive at lens groups with the focal length ratio of -2.88, because such an optical apparatus is capable of performing projection with acceptable brightness and reliable correction of various aberrations (Yamashita, par. [0033]).
The prior art combination of Lu in view of Yamashita does not disclose wherein the focal length of the first lens group denoted by f1 and the focal length of the second lens group denoted by f2 satisfy: 120.0 mm < f1 < 128.0 mm, and -47.0 mm < f2 < -40.0 mm.
In the general field of lens systems, Lohmann teaches lens systems’ parameters, such as focal length, can be scaled linearly (page 4996, column 2 thereof), that is to say, lens systems can be resized by multiplication by an appropriate scaling factor without changing the angles and curvatures of elements in the optical apparatus (see at least Fig. 2 of Lohmann). 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 applied the teachings of Lohmann to the disclosure of Lu, as modified by Yamashita, and multiplied the optical apparatus of Lu by a factor of approximately 20 to arrive at lens groups with a focal length ratio of -2.88 while also having focal lengths for the lens groups within the range 120.0 mm < f1 < 128.0 mm, and -47.0 mm < f2 < -40.0 mm, to scale the size of the image field as necessary for an acceptable image projected (Lohmann, p. 4996, column 2).
Regarding dependent claim 11, Lu in view of Yamashita and Lohmann discloses a projection device, comprising:
an image source (Lu, Fig. 2, imager is an image source, pars. [0016-17]); and
the projection lens group of claim 1 (see rejection of claim 1 above),
wherein the image source is configured to emit light, and the projection lens group is located at a side of the image source to which light is emitted, and a light exit surface of the image source is provided with a protective glass (Figs. 1 and 2, optical engine 10 includes imager with a light source, par. [0017], with the projection lens group arranged at a side of the imager to which light is emitted, and Yamashita discloses a cover glass 4, see Fig. 1 thereof, and refer to par. [0034], equivalent to a protective glass).
Allowable Subject Matter
Claims 2-10 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Regarding dependent claim 2, Lu in view of Yamashita and Lohmann (hereinafter, “modified Lu”) discloses the projection lens group of claim 1, wherein the first lens group comprises a first lens (Lu, Fig. 2, lens group G3 has a first lens equivalent, lens element L11), a second lens (Lu, Fig. 2, lens group G3 has a second lens equivalent, lens element L8) and a doublet lens (Lu, Fig. 2, lens group G3 has a doublet lens of lens elements L9 and L10, refer to Tables 1 and 3), the first lens and the second lens are positive lenses (Lu, Fig. 2, lens elements L11 and L8 have positive refractive power as determined from the parameters in Table 3), and the doublet lens is a negative lens (Lu, Fig. 2, doublet lens element of L9 and L10 has negative refractive power as determined from the parameters in Table 3).
The prior art combination does not disclose the first lens, second lens, and doublet lens are sequentially arranged in the propagation direction of the light (the doublet lens of Lu lens group G3 is between lens elements L11 and L8), and the prior art combination does not disclose wherein the focal length of the first lens denoted by f11, the focal length of the second lens denoted by f12, and a focal length of the doublet lens denoted by f3/4 satisfy: 13.5 mm < f11 < 16.5 mm, 12.5 mm < f12 < 16.5 mm, and -16.5 mm < f3/4 < -12.5 mm.
Regarding dependent claim 3, modified Lu does not disclose all of the limitations of the projection lens group of claim 2, wherein a light incident surface and a light exit surface of the first lens are both convex surfaces, and a light incident surface and a light exit surface of the second lens are both convex surfaces, and
wherein the doublet lens comprises a third lens and a fourth lens sequentially arranged in the propagation direction of the light, a light incident surface of the third lens is a convex surface, a light exit surface of the third lens is a concave surface, a light incident surface and a light exit surface of the fourth lens are both convex surfaces, and the light exit surface of the third lens is bonded to the light incident surface of the fourth lens.
Regarding dependent claim 4, modified Lu does not disclose all of the limitations of the projection lens group of claim 2, but Lu does teach wherein at least one of the light incident surface and the light exit surface of the first lens is an aspheric surface (Lu teaches the inclusion of aspheric lens surfaces, par. [0028]).
Regarding dependent claim 5, modified Lu does not disclose all the limitations of the projection lens group of claim 2, but Lu does teach wherein the first lens is formed of glass (Lu teaches lens element L11 of the lens group G3 is N-PK52 glass in Table 3, par. [0029]).
Regarding dependent claim 6, modified Lu discloses the projection lens group of claim 1, wherein the second lens group comprises a fifth lens, a sixth lens and a seventh lens sequentially arranged in the propagation direction of the light (Lu, Fig. 2, second lens group G2 has lens elements L5, L4, and L3 arranged in the propagation direction of light, equivalent to fifth, sixth, and seventh lenses), the seventh lens is a negative lens (Lu, Fig. 2, second lens group G2 has lens element L3 that has negative focal power as determined from the parameters provided in Table 3).
The prior art combination does not disclose the fifth lens is a positive lens and the sixth lens is a negative lens, and the prior art combination does not disclose wherein a focal length of the fifth lens denoted by f25, a focal length of the sixth lens denoted by f26, and a focal length of the seventh lens denoted by f27 satisfy: 13 mm < f25 < 16 mm, -14.5 mm < f26 < -10.5 mm, and -15.5 mm < f27 < -12.5 mm.
Regarding dependent claim 7, modified Lu does not disclose all the limitations of the projection lens group of claim 6, wherein a light incident surface and a light exit surface of the fifth lens are both convex surfaces, a light incident surface and a light exit surface of the sixth lens are both concave surfaces, a light incident surface of the seventh lens is a concave surface, and a light exit surface of the seventh lens is a convex surface.
Regarding dependent claim 8, modified Lu does not disclose all the limitations of the projection lens group of claim 6, but Lu does teach wherein at least one of the light incident surface and the light exit surface of the seventh lens is an aspheric surface (Lu teaches the inclusion of aspheric lens surfaces, par. [0028]).
Regarding dependent claim 9, modified Lu does not disclose all the limitations of the projection lens group of claim 6, further comprising: a vibrating mirror positioned at a side of the first lens group on which light is incident.
Regarding dependent claim 10, modified Lu does not disclose all the limitations of the projection lens group of claim 9, further comprising: a prism positioned at a side of the vibrating mirror on which light is incident, but Lu does teach the inclusion of a prism positioned at a side on which light is incident (Lu, Fig. 2, a prism is included on the imager side of the lens group G3).
Response to Arguments
Applicant's arguments filed 01/28/2026 have been fully considered but they are not persuasive.
Applicant has argued the cited prior art of Lu, Yamashita, and Lohmann do not teach or suggest the invention as recited in the claims. Specifically, Applicant has argued that the mapping of the lens groups recited in the Office action of 10/30/2025 does not constitute a complete and/or operable projection system. Examiner respectfully disagrees.
Independent claim 1 recites a projection lens group comprising a first lens group and a second lens group, and Lu discloses three lens groups. The mapping of Lu to the elements of the instant application is appropriate and reasonable, because the claim language includes the transitional phrase comprising. Per MPEP 2111.03(I), “The transitional term “comprising", which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. See, e.g., Mars Inc. v. H.J. Heinz Co., 377 F.3d 1369, 1376, 71 USPQ2d 1837, 1843 (Fed. Cir. 2004)”. Therefore, the fact that two lens groups are claimed in the instant application does not bar the mapping of the two lens groups to a prior art reference that discloses three lens groups.
Furthermore, the limitations that the first lens group and second lens group are sequentially arranged in a propagation direction of light and that the first lens group has a positive focal length is met by the third lens group G3 of Lu has positive refractive power (Lu par. [0028]), followed by the second lens group G2 of Lu which has negative refractive power (Lu, par. [0028]). The projection lens disclosed by Lu satisfies the limitations and conditions recited for the first and second lens groups of the instant application. The fact that the Applicant argues that the two lens groups of Lu do not comprise a complete or an operable projection system is not sufficient to demonstrate inoperability. Counsel's assertion that two lens groups of Lu are not operable or complete as a projection system is merely an argument unaccompanied by evidentiary support, and, thus, is insufficient to rebut Examiner's finding of obviousness. Arguments of counsel cannot take the place of evidence in the record. In re Schulze, 346 F.2d 600, 602, 145 USPQ 716, 718 (CCPA 1965); In re Geisler, 116 F.3d 1465, 43 USPQ2d 1362 (Fed. Cir. 1997) (“An assertion of what seems to follow from common experience is just attorney argument and not the kind of factual evidence that is required to rebut a prima facie case of obviousness.”). MPEP §§ 2145, 2129, 2144.03, 716.01(c). In this case, the prior art teaches the limitations regarding the number of lens groups, the sequential arrangement of the lens groups, and the refractive powers of the lens groups recited in independent claim 1, and if the mapping of the elements of Lu to the elements of the instant application do not constitute a complete or an operable projection system, then it is possible the claimed system is neither complete nor operable either. Examiner notes that if the number of lens groups is critical then reciting “consisting of” rather than “comprising” in the preamble would narrow the potential prior art that can satisfy the limitations recited.
Applicant further argues that the secondary reference Yamashita, by teaching an imaging system instead of a projection system, is not technically reasonable to apply to the projection system taught by Lu. Examiner respectfully disagrees.
Per MPEP 904.01(c), “not only must the art be searched within which the invention claimed is classifiable, but also all analogous arts must be searched regardless of where the claimed invention is classified.” Thus, it is required for examiners to search related and analogous art, such as imaging systems, when searching prior art related to projection systems. In this case, both the instant application and the prior art cited are classified in G02B for optical elements, systems or apparatus, and thus it is appropriate and reasonable to refer to prior art disclosures of imaging systems for teachings relevant to projection systems, as both rely on lenses and the arrangement of the optical elements to produce a functional optical system.
With regard to the specific limitations of the focal length for the first and second lens groups, Lohmann is cited to teach the scaling of lens systems to achieve desired focal lengths for lens systems to project acceptable image sizes, as noted in the Office action of 10/30/2025. Since scaling of lens systems does not change the surface shapes or curvatures of lenses, it is reasonable and practical for a person of ordinary skill to look to Lohmann to adjust the scale of the projection system of Lu to produce a system with the claimed focal length ranges for acceptable projected image sizes.
With regard to Applicant’s argument that the mapping of Yamashita lens element 1a to the first lens group of the claimed invention, and of Yamashita second lens element to the second lens group recited in claim 1, is inappropriate because the lens elements of Yamashita are single lenses rather than lens groups, Examiner notes that the number of lens elements in the first and second lens groups of the instant application are not claimed in independent claim 1. Logically, a lens group must contain at least one lens element, and since the number of lens elements in the lens groups recited in independent claim 1 is not disclosed, it is reasonable to map the elements of Yamashita to the recited elements of the instant application to show that the prior art reference Lu and Yamashita both teach, suggest, or disclose similar elements such that a person of ordinary skill would reasonably conclude Yamashita would have teachings relevant to the disclosure of Lu. Furthermore, many prior art references disclosing lens systems, either projecting systems or imaging systems, disclose lens groups consisting of one lens, and thus the argument that a lens group must necessarily have more than one lens is not supported by a search of the relevant prior art that often discloses exactly one lens element in a lens group.
Examiner noted potentially allowable subject matter recited in claims 2-10, where claim 2 discloses the first lens group has first, second, and doublet lenses, and where claim 6 discloses the second lens group has fifth, sixth, and seventh lenses. Incorporation of such subject matter into independent claim 1 would narrow the scope of the claimed subject matter and more distinctly recite the instant invention.
No other substantial arguments were presented after page 10 of Remarks. As such, the prior art teaches the instant invention as currently claimed.
Conclusion
THIS ACTION IS MADE FINAL. 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 Justin W Hustoft whose telephone number is (571)272-4519. The examiner can normally be reached Monday - Friday 8:30 AM - 5:30 PM Eastern Time.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Thomas Pham can be reached at (571)272-3689. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JUSTIN W. HUSTOFT/ Examiner, Art Unit 2872
/THOMAS K PHAM/ Supervisory Patent Examiner, Art Unit 2872