(12) United States Patent
`Dror et al.
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 9,568,712 B2
`*Feb. 14, 2017
`
`USO09568712B2
`
`(54)
`(71)
`(72)
`
`(73)
`(*)
`
`(21)
`(22)
`(65)
`
`(63)
`
`(51)
`
`(52)
`
`MINATURE TELEPHOTO LENS ASSEMBLY
`
`Applicant: Corephotonics Ltd., Tel-Aviv (IL)
`
`Inventors: Michael Dror, Nes Ziona (IL);
`Ephraim Goldenberg, Ashdod (IL);
`Gal Shabtay, Tel Aviv (IL)
`Assignee: Corephotonics Ltd., Tel Aviv (IL)
`
`Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`This patent is Subject to a terminal dis
`claimer.
`
`Appl. No.: 15/170,472
`
`Filed:
`
`Jun. 1, 2016
`
`Prior Publication Data
`US 2016/0291293 A1
`Oct. 6, 2016
`Related U.S. Application Data
`Continuation of application No. 14/932.319, filed on
`Nov. 4, 2015, now Pat. No. 9,402,032, which is a
`(Continued)
`
`Int. C.
`GO2B I3/18
`GO2B 9/62
`GO2B I3/00
`GO2B 9/60
`H04N 5/225
`H04N 5/232
`H04N 9/04
`HO)4N 9/097
`GO2B I3/02
`GO2B I/04
`GO2B 27/00
`
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(Continued)
`
`U.S. C.
`CPC ........... G02B 13/0045 (2013.01); G02B I/041
`
`(2013.01); G02B 9/60 (2013.01); G02B
`13/009 (2013.01); G02B 13/02 (2013.01);
`G02B 27/0025 (2013.01); G02B 27/646
`(2013.01); H04N 5/2254 (2013.01); H04N
`5/2257 (2013.01); H04N 5/2258 (2013.01);
`H04N 5/23296 (2013.01); H04N 9/045
`(2013.01); H04N 9/097 (2013.01); G02B
`5/005 (2013.01); G02B 9/12 (2013.01); G02B
`9/62 (2013.01); G02B 9/64 (2013.01); G02B
`13/00 (2013.01); G02B 13/004 (2013.01);
`G02B 13/18 (2013.01); H04N 2101/00
`(2013.01); Y10T 29/4913 (2015.01)
`(58) Field of Classification Search
`CPC ......... G02B 13/0045; G02B 9/62: G02B 9/60;
`G02B 13/18: G02B 13/004: G02B 9/64;
`G02B 5/005; G02B 13/00; G02B 9/12
`USPC ................ 359/713, 714, 715 717, 739, 740,
`359/745 748, 754 795
`See application file for complete search history.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`9.402,032 B2 * 7/2016 Dror ........................ GO2B 9/60
`* cited by examiner
`Primary Examiner – Evelyn A Lester
`(74) Attorney, Agent, or Firm — Nathan & Associates
`Patent Agents Ltd.; Menachem Nathan
`(57)
`ABSTRACT
`An optical lens assembly includes five lens elements and
`provides a TTL/EFL<1.0. In an embodiment, the focal
`length of the first lens element fl-TTL/2, an air gap between
`first and second lens elements is Smaller than half the second
`lens element thickness, an air gap between the third and
`fourth lens elements is greater than TTL/5 and an air gap
`between the fourth and fifth lens elements is smaller than
`about 1.5 times the fifth lens element thickness. All lens
`elements may be aspheric.
`
`19 Claims, 6 Drawing Sheets
`
`100
`
`X
`
`
`
`'Y10a
`101 - 102 to
`" 106
`106a,
`(7 3.
`
`
`
`APPL-1022 / Page 1 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`US 9,568,712 B2
`Page 2
`
`(60)
`
`(51)
`
`Related U.S. Application Data
`continuation of application No. 14/367.924, filed as
`application No. PCT/IB2014/062465 on Jun. 20,
`2014, now abandoned.
`Provisional application No. 61/843.987, filed on Jul.
`4, 2013.
`
`Int. C.
`GO2B 27/64
`GO2B5/OO
`GO2B 9/64
`GO2B 9/12
`HO4N IOI/OO
`
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`(2006.01)
`
`APPL-1022 / Page 2 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet 1 of 6
`
`US 9,568,712 B2
`
`
`
`APPL-1022 / Page 3 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet 2 of 6
`
`US 9,568,712 B2
`
`O 6
`
`0.0 tes-l
`-0.05 -0.04
`
`(0.01
`0
`-0.03 -0.02 -0.01
`Focus shift (mm)
`Polychromatic Diffraction Through Focus MTF
`Angle 612/2013
`Data for 0.4350 to 0.6560 m.
`Spatial Frequency: 180.0000 cycles/mm.
`
`
`
`Distortion (centroid)
`
`-2.000
`
`30061203
`Maximum distortion = 1.3%
`
`0.000
`Distortion (%)
`
`0.02
`
`0.03
`
`0.04
`
`ex,
`0.05
`
`FIG. 1B
`
`22,000
`19.800
`7,600
`5.400
`3.200
`
`1,000
`8.800
`6,600
`4400
`2.200
`0,000
`2000
`
`FIG. 1C
`
`APPL-1022 / Page 4 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet 3 of 6
`
`US 9,568,712 B2
`
`
`
`APPL-1022 / Page 5 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet 4 of 6
`
`US 9,568,712 B2
`
`O 6
`
`
`
`001 002 003 0.04 0.05
`0
`0.05 -0.04 -0.03 -0.02 -0.01
`Focus shift (mm)
`Polychromatic Diffraction Through Focus MTF
`Angle 612/2013
`Data for 0.4350 to 0.6560 m.
`Spatial Frequency: 180.0000 cyclesimm.
`
`FIG. 2B
`
`
`
`Distortion (centroid)
`
`2,000
`
`30061203
`Maximum distortion = 1.5%
`
`oooo
`Distortion (%)
`
`as
`
`22,000
`9,800
`7.600
`5.400
`3.200
`11,000
`8,800
`6,600
`4400
`2.200
`200,000
`
`FIG. 2C
`
`APPL-1022 / Page 6 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet S of 6
`
`US 9,568,712 B2
`
`
`
`FIG. 3A
`
`APPL-1022 / Page 7 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`U.S. Patent
`
`Feb. 14, 2017
`
`Sheet 6 of 6
`
`US 9,568,712 B2
`
`O
`Focus shift (mm)
`Polychromatic Diffraction Through Focus MTF
`Angle 6/9/2013
`Data for 0.4350 to 0.6560 m.
`Spatia Frequency: 180.0000 cycles/mm.
`
`
`
`Distortion (centroid)
`
`-2.000
`
`0,000
`Distortion (%)
`
`3006/2013
`Maximum distortion = 1.3%
`
`FIG. 3B
`
`22,000
`19,800
`17600
`15.400
`13.200
`11,000
`8,800
`6,600
`4400
`2,200
`0,000
`2,000
`
`FIG. 3C
`
`APPL-1022 / Page 8 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`1.
`MINATURE TELEPHOTO LENS ASSEMBLY
`
`US 9,568,712 B2
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`
`This application is a Continuation application of U.S.
`patent application Ser. No. 14/932,319 filed Nov. 4, 2015,
`which was a Continuation application of U.S. patent appli
`cation Ser. No. 14/367,924 filed Jun. 22, 2014 which was a
`371 of international application PCT/IB2014/062465 filed
`Jun. 20, 2014, and is related to and claims priority from U.S.
`Provisional Patent Application No. 61/842,987 filed Jul. 4,
`2013, which is incorporated herein by reference in its
`entirety.
`
`10
`
`15
`
`FIELD
`
`Embodiments disclosed herein relate to an optical lens
`system and lens assembly, and more particularly, to a
`miniature telephoto lens assembly included in Such a system
`and used in a portable electronic product Such as a cell
`phone.
`
`BACKGROUND
`
`Digital camera modules are currently being incorporated
`into a variety of host devices. Such host devices include
`cellular telephones, personal data assistants (PDAs), com
`puters, and so forth. Consumer demand for digital camera
`modules in host devices continues to grow. Cameras in
`cellphone devices in particular require a compact imaging
`lens system for good quality imaging and with a small total
`track length (TTL). Conventional lens assemblies compris
`ing four lens elements are no longer Sufficient for good
`quality imaging in Such devices. The latest lens assembly
`designs, e.g. as in U.S. Pat. No. 8,395,851, use five lens
`elements. However, the design in U.S. Pat. No. 8,395,851
`suffers from at least the fact that the TTL/EFL (effective
`focal length) ratio is too large.
`Therefore, a need exists in the art for a five lens element
`optical lens assembly that can provide a small TTL/EFL
`ratio and better image quality than existing lens assemblies.
`
`25
`
`30
`
`35
`
`40
`
`SUMMARY
`
`Embodiments disclosed herein refer to an optical lens
`assembly comprising, in order from an object side to an
`image side: a first lens element with positive refractive
`power having a convex object-side Surface, a second lens
`element with negative refractive power having a thickness
`d on an optical axis and separated from the first lens
`element by a first air gap, a third lens element with negative
`refractive power and separated from the second lens element
`by a second air gap, a fourth lens element having a positive
`refractive power and separated from the third lens element
`by a third air gap, and a fifth lens element having a negative
`refractive power, separated from the fourth lens element by
`a fourth air gap, the fifth lens element having a thickness ds
`on the optical axis.
`An optical lens system incorporating the lens assembly
`may further include a stop positioned before the first lens
`element, a glass window disposed between the image-side
`Surface of the fifth lens element and an image sensor with an
`image plane on which an image of the object is formed.
`The effective focal length of the lens assembly is marked
`“EFL and the total track length on an optical axis between
`the object-side surface of the first lens element and the
`electronic sensor is marked “TTL'. In all embodiments,
`TTL is smaller than the EFL, i.e. the TTL/EFL ratio is
`smaller than 1.0. In some embodiments, the TTL/EFL ratio
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`is smaller than 0.9. In an embodiment, the TTL/EFL ratio is
`about 0.85. In all embodiments, the lens assembly has an F
`number Fik3.2. In an embodiment, the focal length of the
`first lens element fl is smaller than TTL/2, the first, third and
`fifth lens elements have each an Abbe number (“Vd)
`greater than 50, the second and fourth lens elements have
`each an Abbe number smaller than 30, the first air gap is
`Smaller than d/2, the third air gap is greater than TTL/5 and
`the fourth air gap is smaller than 1.5ds. In some embodi
`ments, the Surfaces of the lens elements may be aspheric.
`In an optical lens assembly disclosed herein, the first lens
`element with positive refractive power allows the TTL of the
`lens system to be favorably reduced. The combined design
`of the first, second and third lens elements plus the relative
`short distances between them enable a long EFL and a short
`TTL. The same combination, together with the high disper
`sion (low Vd) for the second lens element and low disper
`sion (high Vd) for the first and third lens elements, also helps
`to reduce chromatic aberration. In particular, the ratio TTL/
`EFL-1.0 and minimal chromatic aberration are obtained by
`fulfilling the relationship 1.2xf3Dlf2|>1.5.xf1.
`where “f indicates the lens element effective focal length
`and the numerals 1, 2, 3, 4, 5 indicate the lens element
`number.
`The relatively large distance between the third and the
`fourth lens elements plus the combined design of the fourth
`and fifth lens elements assist in bringing all fields focal
`points to the image plane. Also, because the fourth and fifth
`lens elements have different dispersions and have respec
`tively positive and negative power, they help in minimizing
`chromatic aberration.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1A shows a first embodiment of an optical lens
`system disclosed herein;
`FIG. 1B shows the modulus of the optical transfer func
`tion (MTF) vs. focus shift of the entire optical lens assembly
`for various fields in the first embodiment;
`FIG. 1C shows the distortion vs. field angle (+Y direction)
`in percent in the first embodiment;
`FIG. 2A shows a second embodiment of an optical lens
`system disclosed herein;
`FIG. 2B Shows the MTF vs. focus shift of the entire
`optical lens assembly for various fields in the second
`embodiment;
`FIG. 2C shows the distortion +Y in percent in the second
`embodiment;
`FIG. 3A shows a third embodiment of an optical lens
`system disclosed herein;
`FIG. 3B shows the MTF vs. focus shift of the entire
`optical lens system for various fields in the third embodi
`ment;
`FIG. 3C shows the distortion +Y in percent in the third
`embodiment.
`
`DETAILED DESCRIPTION
`
`In the following description, the shape (convex or con
`cave) of a lens element surface is defined as viewed from the
`respective side (i.e. from an object side or from an image
`side). FIG. 1A shows a first embodiment of an optical lens
`system disclosed herein and marked 100. FIG. 1B shows the
`MTF vs. focus shift of the entire optical lens system for
`various fields in embodiment 100. FIG. 1C shows the
`distortion +Y in percent vs. field Embodiment 100 com
`prises in order from an object side to an image side: an
`optional stop 101; a first plastic lens element 102 with
`positive refractive power having a convex object-side Sur
`face 102a and a convex or concave image-side surface 102b:
`a second plastic lens element 104 with negative refractive
`
`APPL-1022 / Page 9 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`US 9,568,712 B2
`
`10
`
`15
`
`3
`power and having a meniscus convex object-side Surface
`104a, with an image side surface marked 104b; a third
`plastic lens element 106 with negative refractive power
`having a concave object-side surface 106a with an inflection
`point and a concave image-side surface 106b; a fourth s
`plastic lens element 108 with positive refractive power
`having a positive meniscus, with a concave object-side
`Surface marked 108a and an image-side Surface marked
`108b; and a fifth plastic lens element 110 with negative
`refractive power having a negative meniscus, with a concave
`object-side Surface marked 110a and an image-side Surface
`marked 110b. The optical lens system further comprises an
`optional glass window 112 disposed between the image-side
`surface 110b of fifth lens element 110 and an image plane
`114 for image formation of an object. Moreover, an image
`sensor (not shown) is disposed at image plane 114 for the
`image formation.
`In embodiment 100, all lens element surfaces are
`aspheric. Detailed optical data is given in Table 1, and the
`aspheric Surface data is given in Table 2, wherein the units
`of the radius of curvature (R), lens element thickness and/or
`distances between elements along the optical axis and diam
`eter are expressed in mm “Nd' is the refraction index. The
`equation of the aspheric Surface profiles is expressed by:
`
`TABLE 1.
`
`# Comment
`
`Radius R Distances
`mm
`mm
`
`N.V.
`
`Diameter
`mm
`
`1
`2
`
`3
`
`4
`
`5
`
`6
`
`7
`8
`
`9
`
`10
`
`Stop
`L11
`
`L12
`
`L21
`
`L22
`
`L31
`
`L32
`L41
`
`L42
`
`LS1
`
`LS2
`11
`12 Window
`13
`
`Infinite
`1.S800
`
`-11.2003
`
`33.8670
`
`3.2281
`
`-12.2843
`
`7.7138
`-2.3755
`
`-1.88O1
`
`-1.81OO
`
`-S-2768
`Infinite
`Infinite
`
`-0.466
`O894
`
`O.O2O
`
`O.246
`
`O449
`
`O.290
`
`2.02O
`0.597
`
`O.O68
`
`O.293
`
`O.617
`O.210
`O.200
`
`1.5345, 57.095
`
`1.63549,23.91
`
`1.5345, 57.095
`
`1.63549,23.91
`
`1.5345, 57.095
`
`1.S168,64.17
`
`2.4
`2.5
`
`2.4
`
`2.2
`
`1.9
`
`1.9
`
`1.8
`3.3
`
`3.6
`
`3.9
`
`4.3
`3.0
`3.0
`
`TABLE 2
`
`Conic
`coefficient
`
`i
`
`C2
`
`C3
`
`C4
`
`Cls
`
`C6
`
`-04668
`-9.852S
`10.7569
`1.4395
`O.OOOO
`-9.8953
`O.9938
`-6.8097
`-7.3161
`O.OOOO
`
`7.9218E-O3 2.3146E-O2 -3.3436E-O2 2.365OE-O2 -9.2437E-O3
`2.0102E-O2 2.0647E-04 7.4394E-O3 -1.7529E-O2 45206E-03
`-19248E-O3 8.60O3E-O2 1.1676E-O2 -4.06O7E-O2 13545E-02
`5.1029E-03 2.4578E-O1 -1.7734E-O1 2.9848E-O1 -1332OE-O1
`2.1629E-O1 4.O134E-O2 1.3615E-02 2.5914E-O3 -12292E-O2
`23297E-O1 8.2917E-O2 -12725E-O1 15691E-O1 -5.9624E-O2
`-13522E-O2 -7.0395E-03 14569E-02 -15336E-O2 4.3707E-O3
`-10654E-O1 12933E-O2 2.9548E-04 -18317E-O3 SO111E-04
`-18636E-O1 8.31 OSE-O2 -18632E-O2 2.4012E-O3 -128.16E-04
`-11927E-O1 7.0245E-02 -2.0735E-O2 2.6418E-O3 -1.1576E-04
`
`—
`1 + V1-(1 + k2
`
`where r is distance from (and perpendicular to) the optical
`axis, k is the conic coefficient, c=1/R where R is the radius
`of curvature, and a are coefficients given in Table 2. In the
`equation above as applied to embodiments of a lens assem
`bly disclosed herein, coefficients C. and C., are Zero. Note
`that the maximum value of r"max r=Diameter/2. Also note
`that Table 1 (and in Tables 3 and 5 below), the distances
`between various elements (and/or surfaces) are marked
`“Limn” (where m refers to the lens element number, n=1
`refers to the element thickness and n=2 refers to the air gap
`to the next element) and are measured on the optical axis Z.
`wherein the stop is at Z-0. Each number is measured from
`the previous surface. Thus, the first distance -0.466 mm is
`measured from the stop to surface 102a, the distance L11
`from surface 102a to surface 102b (i.e. the thickness of first
`lens element 102) is 0.894 mm, the gap L12 between
`surfaces 102b and 104a is 0.020 mm, the distance L21
`between surfaces 104a and 104b (i.e. thickness d2 of second
`lens element 104) is 0.246 mm, etc. Also, L21=d and
`L51=ds.
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Embodiment 100 provides a field of view (FOV) of 44
`degrees, with EFL=6.90 mm, F#=2.80 and TTL of 5.904
`mm Thus and advantageously, the ratio TTL/EFL=0.855.
`Advantageously, the Abbe number of the first, third and fifth
`lens element is 57.095. Advantageously, the first air gap
`between lens elements 102 and 104 (the gap between
`surfaces 102b and 104a) has a thickness (0.020 mm) which
`is less than a tenth of thickness d (0.246 mm) Advanta
`geously, the Abbe number of the second and fourth lens
`elements is 23.91. Advantageously, the third air gap between
`lens elements 106 and 108 has a thickness (2.020 mm)
`greater than TTL/5 (5.904/5 mm) Advantageously, the
`fourth air gap between lens elements 108 and 110 has a
`thickness (0.068 mm) which is smaller than 1.5ds (0.4395
`mm).
`The focal length (in mm) of each lens element in embodi
`ment 100 is as follows: fl=2.645, f2=-5.578, f3=-8.784,
`f4=9.550 and fS=-5.290. The condition 1.2xf3>|f2|<1.5x
`fl is clearly satisfied, as 1.2x8.78725.578>1.5x2.645. fl
`also fulfills the condition fl-TTL/2, as 2.645<2.952.
`FIG. 2A shows a second embodiment of an optical lens
`system disclosed herein and marked 200. FIG. 2B shows the
`MTF vs. focus shift of the entire optical lens system for
`various fields in embodiment 200. FIG. 2C shows the
`distortion +Y in percent vs. field. Embodiment 200 com
`prises in order from an object side to an image side: an
`optional stop 201; a first plastic lens element 202 with
`positive refractive power having a convex object-side Sur
`
`APPL-1022 / Page 10 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`5
`face 202a and a convex or concave image-side Surface 202b:
`a second glass lens element 204 with negative refractive
`power, having a meniscus convex object-side Surface 204a.
`with an image side surface marked 204b; a third plastic lens
`element 206 with negative refractive power having a con
`cave object-side surface 206a with an inflection point and a
`concave image-side Surface 206b; a fourth plastic lens
`element 208 with positive refractive power having a positive
`meniscus, with a concave object-side Surface marked 208a
`and an image-side surface marked 208b; and a fifth plastic
`lens element 210 with negative refractive power having a
`negative meniscus, with a concave object-side Surface
`marked 110a and an image-side surface marked 210b. The
`optical lens system further comprises an optional glass
`window 212 disposed between the image-side surface 210b
`of fifth lens element 210 and an image plane 214 for image
`formation of an object.
`In embodiment 200, all lens element surfaces are
`aspheric. Detailed optical data is given in Table 3, and the
`aspheric Surface data is given in Table 4, wherein the
`markings and units are the same as in, respectively, Tables
`1 and 2. The equation of the aspheric surface profiles is the
`same as for embodiment 100.
`
`TABLE 3
`
`# Comment
`
`Radius R
`mm
`
`Distances
`mm
`
`N.V.
`
`Diameter
`mm
`
`Stop
`L11
`L12
`L21
`L22
`L31
`L32
`LA1
`LA2
`LS1
`L52
`Window
`
`Infinite
`1.5457
`-127.7249
`6.606S
`2.8090
`9.6183
`3.4694
`-2.6432
`-1.8663
`-14933
`-4.1588
`Infinite
`Infinite
`
`-0.592
`O.898
`O.129
`O.251
`O443
`O.293
`1.766
`O.696
`O. 106
`O.330
`O649
`O.210
`O.130
`
`1.53463.56.18
`
`1.91266,20.65
`
`1.53463.56.18
`
`1.632445,23.35
`
`1.53463.56.18
`
`1.S168,64.17
`
`2.5
`2.6
`2.6
`2.1
`1.8
`1.8
`1.7
`3.2
`3.6
`3.9
`4.3
`5.4
`5.5
`
`1
`
`:
`
`1 3
`
`US 9,568,712 B2
`
`6
`between lens elements 208 and 210 has a thickness (0.106
`mm) which is less than 1.5xds (0.495 mm).
`The focal length (in mm) of each lens element in embodi
`ment 200 is as follows: fl=2.851, f2=-5.468, f3=-10.279,
`f4=7.368 and fS=-4.536. The condition 1.2xf3>|f2|<1.5x
`fl is clearly satisfied, as 1.2x10.2795.468>1.5x2.851. fl
`also fulfills the condition fl-TTL/2, as 2.851<2.950.
`FIG. 3A shows a third embodiment of an optical lens
`system disclosed herein and marked 300. FIG. 3B shows the
`MTF vs. focus shift of the entire optical lens system for
`various fields in embodiment 300. FIG. 3C shows the
`distortion +Y in percent vs. field. Embodiment 300 com
`prises in order from an object side to an image side: an
`optional stop 301; a first glass lens element 302 with positive
`refractive power having a convex object-side surface 302a
`and a convex or concave image-side Surface 302b; a second
`plastic lens element 204 with negative refractive power,
`having a meniscus convex object-side surface 304a, with an
`image side surface marked 304b; a third plastic lens element
`306 with negative refractive power having a concave object
`side surface 306a with an inflection point and a concave
`image-side surface 306b; a fourth plastic lens element 308
`with positive refractive power having a positive meniscus,
`with a concave object-side surface marked 308a and an
`image-side surface marked 308b; and a fifth plastic lens
`element 310 with negative refractive power having a nega
`tive meniscus, with a concave object-side Surface marked
`310a and an image-side surface marked 310b. The optical
`lens system further comprises an optional glass window 312
`disposed between the image-side surface 310b of fifth lens
`element 310 and an image plane 314 for image formation of
`an object.
`In embodiment 300, all lens element surfaces are
`aspheric. Detailed optical data is given in Table 5, and the
`aspheric surface data is given in Table 6, wherein the
`markings and units are the same as in, respectively, Tables
`1 and 2. The equation of the aspheric surface profiles is the
`same as for embodiments 100 and 200.
`
`10
`
`15
`
`25
`
`30
`
`35
`
`TABLE 4
`
`Conic
`coefficient
`k
`
`i
`
`C2
`
`C3
`
`C4
`
`Cls
`
`O.OOOO
`-1O.O119
`1.O.O220
`7.2902
`O.OOOO
`8.1261
`O.OOOO
`O.OOOO
`-47688
`
`-2.7367E-03
`4.079OE-02
`4.6151E-O2
`3.6028E-O2
`1.6639E-O1
`1.53S3E-O1
`-3.2628E-O2
`15173E-O2
`-14736E-O1
`-8.3741E-O2
`
`2.8779E-04
`-1.83.79E-02
`5.832OE-02
`11436E-O1
`S.67 S4E-O2
`8.1427E-O2
`1953SE-O2
`-1.2252E-O2
`7.6335E-02
`4.266OE-O2
`
`-4.3661E-O3
`2.2562E-O2
`-2.0919E-O2
`-19022E-O2
`-1.2238E-O2
`-1.5773E-O1
`-1.6716E-O2
`3.3611E-03
`-2.SS39E-02
`-8.4866E-O3
`
`3.0069E-03 - 12282E-03
`-1.77O6E-O2
`4.964OE-03
`-1.2846E-02
`8.8283E-03
`4.7992E-03
`-3.4O79E-03
`19292E-O2
`-1.8648E-O2
`-4.6064E-02
`2O112E-03
`8.4038E-04
`-SO29OE-04
`7.2785E-05
`
`-2.O132E-03
`-2.53O3E-03
`
`12183E-04
`
`Embodiment 200 provides a FOV of 43.48 degrees, with
`EFL=7 mm, FH-2.86 and TTL=5.90 mm Thus and advan
`tageously, the ratio TTL/EFL=0.843. Advantageously, the
`Abbe number of the first, third and fifth lens elements is
`56.18. The first air gap between lens elements 202 and 204
`has a thickness (0.129 mm) which is about half the thickness
`d (0.251 mm) Advantageously, the Abbe number of the
`second lens element is 20.65 and of the fourth lens element
`is 23.35. Advantageously, the third air gap between lens
`elements 206 and 208 has a thickness (1.766 mm) greater
`than TTL/5 (5.904/5 mm) Advantageously, the fourth air gap
`
`TABLE 5
`
`60
`
`# Comment
`
`Radius R Distances
`mm
`mm
`
`N.V.
`
`Diameter
`mm
`
`1
`2
`3
`4
`5
`6
`
`Stop
`L11
`L12
`L21
`L22
`L31
`
`Infinite
`1.5127
`-1338.31
`8.4411
`2.6181
`-17.9618
`
`-0.38
`O.919
`O.O29
`O.254
`O426
`O.26S
`
`65
`
`1.5148,63.1
`
`163549,23.91
`
`1.5345,57.09
`
`2.4
`2.5
`2.3
`2.1
`1.8
`1.8
`
`APPL-1022 / Page 11 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`US 9,568,712 B2
`
`7
`TABLE 5-continued
`
`# Comment
`
`L32
`7
`LA1
`8
`LA2
`9
`LS1
`10
`L52
`11
`12 Window
`13
`
`Radius R Distances
`mm
`mm
`
`N.V.
`
`Diameter
`mm
`
`4.5841
`-2.8827
`- 19771
`-1.8665
`-6.3670
`Infinite
`Infinite
`
`1998
`O514
`O.121
`O431
`O.S38
`O.210
`O.200
`
`163549,23.91
`
`1.5345,57.09
`
`1.S168,64.17
`
`1.7
`3.4
`3.7
`4.0
`4.4
`3.0
`3.0
`
`10
`
`8
`2. The lens assembly of claim 1, wherein the plurality of
`lens elements further comprises a fourth lens element, the
`third and fourth lens elements being separated by an air gap
`greater than TTL/5.
`3. The lens assembly of claim 2, wherein the third lens
`element has a negative refractive power.
`4. The lens assembly of claim 2, wherein the plurality of
`lens elements further comprises a fifth lens element and
`wherein one of the fourth and the fifth lens elements has a
`positive refractive power and the other of the fourth and fifth
`lens elements has a negative refractive power.
`
`TABLE 6
`
`Conic
`coefficient
`k
`
`i
`
`C2
`
`C3
`
`C4
`
`Cls
`
`1.3253E-O2 2.3699E-02 -2.85O1E-O2 1.7853E-O2
`-0.534
`2
`3.0077E-O2 4.7972E-O3 1.447SE-O2 -1849OE-02
`3 -13473
`7.0372E-04 11328E-O1 12346E-O3 -4.2655E-02
`4 -10.132
`5
`5.180 -1921OE-O3 2.3799E-01 -8.805SE-O2 2.1447E-O1
`6
`O.OOO
`2.678OE-O1 18129E-02 -1.7323E-O2 3.7372E-O2
`7
`10.037
`2.766OE-O1 -1.0291E-O2 - 6.0955E-O2 7.5235E-02
`8
`1.703
`2.6462E-O2 -1.2633E-O2 -4.7724E-04 -3.2762E-O3
`9
`-1.456
`S.7704E-O3 -18826E-O2 S.1593E-03 -2.9999E-03
`10
`-6.511 -2.1699E-01 13692E-O1 -42629E-O2 6.8371E-03
`11
`O.OOO -1512OE-O1 8.6614E-O2 -2.3324E-O2 2.7361E-O3
`
`-40314E-03
`4.356SE-03
`8.862SE-03
`-1.27O2E-O1
`-21356E-O2
`-1.6521E-O2
`1.6SS1E-03
`8.O685E-04
`-4.1415E-04
`-1.1236E-04
`
`Embodiment 300 provides a FOV of 44 degrees, EFL–6.84
`mm, FH-2.80 and TTL=5.904 mm Thus and advanta
`geously, the ratio TTL/EFL=0.863. Advantageously, the
`Abbe number of the first lens element is 63.1, and of the
`third and fifth lens elements is 57.09. The first air gap
`between lens elements 302 and 304 has a thickness (0.029
`mm) which is about Mo' the thickness d (0.254 mm)
`Advantageously, the Abbe number of the second and fourth
`lens elements is 23.91. Advantageously, the third air gap
`between lens elements 306 and 308 has a thickness (1.998
`mm) greater than TTL/5 (5.904/5 mm) Advantageously, the
`fourth air gap between lens elements 208 and 210 has a
`thickness (0.121 mm) which is less than 1.5ds (0.6465mm).
`The focal length (in mm) of each lens element in embodi
`ment 300 is as follows: fl=2.687, f2=-6.016, f3=-6.777,
`fA=8.026 and fS=-5.090. The condition 1.2xf3>|f2|<1.5x
`f1 is clearly satisfied, as 1.2x6.777 d6.016>1.5x2.687. f1
`also fulfills the condition fl-TTL/2, as 2.687<2.952.
`While this disclosure has been described in terms of
`certain embodiments and generally associated methods,
`alterations and permutations of the embodiments and meth
`ods will be apparent to those skilled in the art. The disclosure
`is to be understood as not limited by the specific embodi
`ments described herein, but only by the scope of the
`appended claims.
`What is claimed is:
`1. A lens assembly, comprising: a plurality of refractive
`lens elements arranged along an optical axis, wherein at least
`one surface of at least one of the plurality of lens elements
`is aspheric, wherein the lens assembly has an effective focal
`length (EFL), a total track length (TTL) of 6.5 millimeters
`or less and a ratio TTL/EFL of less than 1.0, and wherein the
`plurality of lens elements comprises, in order from an object
`side to an image side, a first lens element with a focal length
`f1 and positive refractive power, a second lens element with
`a focal length f2 and negative refractive power and a third
`lens element with a focal length f3, the focal length fl, the
`focal length f2 and the focal length f3 fulfilling the condition
`1.2xf3>|f2>1.5xf1.
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5. The lens assembly of claim 4, wherein the fourth lens
`element and the fifth lens element are separated by a second
`air gap smaller than TTL/20.
`6. The lens assembly of claim 2, wherein a lens assembly
`F# is smaller than 2.9.
`7. The lens assembly of claim 2, wherein the first lens
`element has an Abbe number greater than 50 and wherein the
`second lens element has an Abbe number smaller than 30.
`8. The lens assembly of claim 4, wherein one of the fourth
`and fifth lens elements that has a positive refractive power
`is characterized by an Abbe number smaller than 30 and
`wherein the other of the fourth and fifth lens elements that
`has a negative refractive power is characterized by an Abbe
`number greater than 50.
`9. The lens assembly of claim 8, wherein the first lens
`element has a convex object-side Surface and a convex or
`concave image-side Surface and wherein the second lens
`element is a meniscus lens having a convex object-side
`Surface.
`10. The lens assembly of claim 4, wherein the third, fourth
`and fifth lens element are made of plastic.
`11. The lens assembly of claim 4, wherein all the lens
`elements are made of plastic.
`12. The lens assembly of claim 1, wherein the first lens
`element has an Abbe number greater than 50 and the second
`lens element has an Abbe number smaller than 30.
`13. The lens assembly of claim 12, wherein the first lens
`element has a convex object-side Surface and a convex or
`concave image-side Surface and wherein the second lens
`element is a meniscus lens having a convex object-side
`Surface.
`14. The lens assembly of claim 13, wherein a lens
`assembly F if is smaller than 2.9.
`15. A lens assembly, comprising: a plurality of refractive
`lens elements arranged along an optical axis, wherein the
`lens assembly has an effective focal length (EFL) and a total
`track length (TTL) smaller than the effective focal length
`(EFL), the plurality of refractive lens elements comprising,
`in order from an object plane to an image plane along the
`
`APPL-1022 / Page 12 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`

`

`10
`
`US 9,568,712 B2
`
`optical axis, a first lens element having positive optical
`power, a pair of second and third lens elements having
`together a negative optical power, and a combination of
`fourth and fifth lens elements, the fourth lens element
`separated from the third lens element by an air gap greater
`than TTL/5.
`16. The lens assembly of claim 15, wherein the first lens
`element has an Abbe number greater than 50 and wherein the
`second lens element has an Abbe number smaller than 30.
`17. The lens assembly of claim 16, wherein the second
`and third lens elements have each a negative optical power.
`18. The lens assembly of claim 16, wherein the plurality
`of refractive lens elements are made of at least two different
`polymer materials having different Abbe numbers, wherein
`the second and third lens elements are each made of a
`different one of the at least two polymer materials, and
`wherein the fourth and fifth lens elements are each made of
`a different one of the at least two polymer materials.
`19. The lens assembly of claim 16, wherein the TTL is 6.5
`millimeters or less.
`
`10
`
`15
`
`APPL-1022 / Page 13 of 13
`APPLE INC. v. COREPHOTONICS LTD.
`
`