Lens assembly

[0001] The invention relates to a lens assembly.

[0002] The current development trend of a lens assembly is toward high resolution. In addition, the number of lenses used in lens assembly is increasing, making the total length of the imaging lenses longer and longer, which can't satisfy such requirements of miniaturization. Therefore, the lens assembly needs a new structure in order to meet the requirements of high resolution and miniaturization at the same time.

[0003] The invention provides a lens assembly to solve the above problems. The lens assembly of the invention is provided with characteristics of a decreased total length of the lens assembly, a higher resolution and still has a good optical performance.

[0004] The lens assembly in accordance with an exemplary embodiment of the invention includes a first lens, a second lens, a third lens, and a fourth lens, all of which are arranged in order from an object side to an image side along an optical axis. The first lens is a meniscus lens with positive refractive power, and includes a convex surface facing the object side and a concave surface facing the image side. The second lens is with negative refractive power. The third lens is with positive refractive power. The fourth lens is a meniscus lens with refractive power. The lens assembly satisfies at least one of following conditions:−0.1≤R₁₁/R₄₂≤0.53; 2≤TTL/SD4≤7; 0.1≤SD1/f≤0.6; wherein R₁₁ is a radius of curvature of the object side surface of the first lens, R₄₂ is a radius of curvature of the image side surface of the fourth lens, TTL is an interval in mm from the object side surface of the first lens to an image plane along the optical axis, SD4 is an optical effective diameter in mm of the fourth lens, SD1 is an optical effective diameter in mm of the first lens, and f is an effective focal length in mm of the lens assembly. The basic operation of the lens assembly in the present invention can be achieved by satisfying the features of the exemplary embodiment without requiring other conditions.

[0005] In another exemplary embodiment, the second lens includes a concave surface facing the image side, and the third lens is a biconvex lens and includes a convex surface facing the object side and another convex surface facing the image side.

[0006] In yet another exemplary embodiment, the fourth lens is with positive refractive power.

[0007] In another exemplary embodiment, the fourth lens is with negative refractive power.

[0008] In yet another exemplary embodiment, the second lens further includes another concave surface facing the object side, and the fourth lens includes a convex surface facing the object side and a concave surface facing the image side.

[0009] In another exemplary embodiment, the second lens includes a convex surface facing the object side, and the fourth lens includes a concave surface facing the object side and a convex surface facing the image side.

[0010] In yet another exemplary embodiment, the fourth lens includes a concave surface facing the object side and a convex surface facing the image side while the second lens includes a convex surface facing the object side, and the fourth lens includes a convex surface facing the object side and a concave surface facing the image side while the second lens includes a concave surface facing the object side.

[0011] In another exemplary embodiment, the lens assembly further includes a stop disposed between the first lens and the second lens.

[0012] In yet another exemplary embodiment, the lens assembly further includes a stop disposed between the first lens and the second lens, and the lens assembly satisfies at least one of following conditions: 0≤SD4/TTL≤0.5; 0.05≤SL1/TTL≤0.5; 0.1≤SD4/SL2≤0.8; wherein TTL is an interval in mm from the object side surface of the first lens to the image plane along the optical axis, SD4 is an optical effective diameter in mm of the fourth lens, SL1 is an interval in mm from the object side surface of the first lens to the stop along the optical axis, and SL2 is an interval in mm from the stop to the image plane along the optical axis.

[0013] In another exemplary embodiment, the lens assembly satisfies at least one of following conditions: −10≤f4/BFL≤−3; 19≤|f4/BFL|≤52 ; wherein f₄ is an effective focal length in mm of the fourth lens and BFL is an interval in mm from the image side surface of the fourth lens to the image plane along the optical axis.

[0014] The lens assembly in accordance with another exemplary embodiment of the invention includes a first lens, a second lens, a third lens, and a fourth lens, all of which are arranged in order from an object side to an image side along an optical axis. The first lens is a meniscus lens with positive refractive power, and includes a convex surface facing the object side and a concave surface facing the image side. The second lens is with negative refractive power. The third lens is with positive refractive power. The fourth lens is a meniscus lens with refractive power. The fourth lens comprises a concave surface facing the object side and a convex surface facing the image side while the second lens comprises a convex surface facing the object side, or the fourth lens comprises a convex surface facing the object side and a concave surface facing the image side while the second lens comprises a concave surface facing the object side. The lens assembly satisfies at least one of following conditions: 0.1≤SD1/f≤0.6; wherein SD1 is an optical effective diameter in mm of the first lens and f is an effective focal length in mm of the lens assembly. The basic operation of the lens assembly in the present invention can be achieved by satisfying the features of the exemplary embodiment without requiring other conditions.

[0015] In another exemplary embodiment, the lens assembly satisfies at least one of following conditions: −0.1≤R₁₁/R₄₂≤0.53; 2≤TTL/SD4≤7; −10≤f4/BFL≤−3; 0≤SD4/TTL≤0.5; 19≤|f4/BFL|≤52 ; wherein R₁₁ is a radius of curvature of the object side surface of the first lens, R₄₂ is a radius of curvature of the image side surface of the fourth lens, TTL is an interval in mm from the object side surface of the first lens to an image plane along the optical axis, SD4 is an optical effective diameter in mm of the fourth lens, f₄ is an effective focal length in mm of the fourth lens, BFL is an interval in mm from the image side surface of the fourth lens to an image plane along the optical axis, and f is an effective focal length in mm of the lens assembly

[0016] In yet another exemplary embodiment, the fourth lens is with positive refractive power or with negative refractive power.

[0017] A detailed description is given in the following embodiments with reference to the accompanying drawings.

[0030] The following description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.

[0031] The present invention provides a lens assembly including a first lens, a second lens, a third lens, and a fourth lens. The first lens is a meniscus lens with positive refractive power, and includes a convex surface facing an object side and a concave surface facing an image side. The second lens is with negative refractive power. The third lens is with positive refractive power. The fourth lens is a meniscus lens with refractive power. The first lens, the second lens, the third lens, and the fourth lens are arranged in order from the object side to the image side along an optical axis. The lens assembly satisfies at least one of following conditions: −0.1≤R₁₁/R₄₂≤0.53; 2≤TTL/SD4≤7; 0.1≤SD1/f≤0.6; wherein R₁₁ is a radius of curvature of the object side surface of the first lens, R₄₂ is a radius of curvature of the image side surface of the fourth lens, TTL is an interval in mm from the object side surface of the first lens to an image plane along the optical axis, SD4 is an optical effective diameter in mm of the fourth lens, SD1 is an optical effective diameter in mm of the first lens, and f is an effective focal length in mm of the lens assembly.

[0032] Referring to Table 1, Table 2, Table 4, Table 5, Table 7, Table 8, Table 10, Table 11, Table 13, Table 14, Table 16, Table 17, Table 19, and Table 20, wherein Table 1, Table 4, Table 7, Table 10, Table 13, Table 16, and Table 19 show optical specification in accordance with a first, second, third, fourth, fifth, sixth, and seventh embodiments of the invention respectively and Table 2, Table 5, Table 8, Table 11, Table 14, Table 17, and Table 20 show aspheric coefficient of each aspheric lens in Table 1, Table 4, Table 7, Table 10, Table 13, Table 16, and Table 19 respectively.

[0033] FIG. 1, FIG. 3, FIG. 5, FIG. 7, FIG. 9, FIG. 10, and FIG. 11 are lens layout and optical path diagrams of the lens assembly in accordance with the first, second, third, fourth, fifth, sixth, and seventh embodiments of the invention respectively. The first lens L11, L21, L31, L41, L51, L61, L71 are meniscus lenses with positive refractive power and made of glass material, wherein the object side surfaces S11, S21, S31, S41, S51, S61, S71 are convex surfaces, the image side surfaces S12, S22, S32, S42, S52, S62, S72 are concave surfaces, and the object side surfaces S11, S21, S31, S41, S51, S61, S71 and the image side surfaces S12, S22, S32, S42, S52, S62, S72 are aspheric surfaces.

[0034] The second lens L12, L22, L32, L42, L52, L62, L72 are with negative refractive power and made of plastic material, wherein the image side surfaces S15, S25, S35, S45, S55, S65, S75 are concave surfaces, and the object side surfaces S14, S24, S34, S44, S54, S64, S74 and the image side surfaces S15, S25, S35, S45, S55, S65, S75 are aspheric surfaces.

[0035] The third lens L13, L23, L33, L43, L53, L63, L73 are biconvex lenses with positive refractive power which helps to extend the distance of back focal length and made of plastic material, wherein the object side surfaces S16, S26, S36, S46, S56, S66, S76 are convex surfaces, the image side surfaces S17, S27, S37, S47, S57, S67, S77 are convex surfaces, and the object side surfaces S16, S26, S36, S46, S56, S66, S76 and the image side surfaces S17, S27, S37, S47, S57, S67, S77 are aspheric surfaces.

[0036] The fourth lens L14, L24, L34, L44, L54, L64, L74 are meniscus lenses with refractive power and made of plastic material, wherein the object side surfaces S18, S28, S38, S48, S58, S68, S78 and the image side surfaces S19, S29, S39, S49, S59, S69, S79 are aspheric surface.

[0037] The above positive and negative refractive power structure helps to improve resolution, correct aberrations, and correct chromatic aberrations. In addition, the lens assembly 1, 2, 3, 4, 5, 6, 7 satisfy at least one of the following conditions:

[0038] $\begin{array}{cc}-0.1\le R_{11}/R_{42}\le 0.53;& \left(1\right)\end{array}$ $\begin{array}{cc}2\le \mathrm{TTL}/\mathrm{SD}4\le 7;& \left(2\right)\end{array}$ $\begin{array}{cc}-10\le f4/\mathrm{BFL}\le -3;& \left(3\right)\end{array}$ $\begin{array}{cc}0\le \mathrm{SD}4/\mathrm{TTL}\le 0.5;& \left(4\right)\end{array}$ $\begin{array}{cc}0.05\le \mathrm{SL}1/\mathrm{TTL}\le 0.5;& \left(5\right)\end{array}$ $\begin{array}{cc}0.1\le \mathrm{SD}4/\mathrm{SL}2\le 0.8;& \left(6\right)\end{array}$ $\begin{array}{cc}0.1\le \mathrm{SD}1/f\le 0.6;& \left(7\right)\end{array}$ $\begin{array}{cc}19\le ❘f4/\mathrm{BFL}❘\le 52& \left(8\right)\end{array}$
wherein R₁₁ is a radius of curvature of the object side surface S11, S21, S31, S41, S51, S61, S71 of the first lens L11, L21, L31, L41, L51, L61, L71 for the first to seventh embodiments, R₄₂ is a radius of curvature of the image side surface S19, S29, S39, S49, S59, S69, S79 of the fourth lens L14, L24, L34, L44, L54, L64, L74 for the first to seventh embodiments, TTL is an interval in mm from the object side surfaces S11, S21, S31, S41, S51, S61, S71 of the first lenses L11, L21, L31, L41, L51, L61, L71 to the image planes IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, IMA7 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, OA7 respectively for the first to seventh embodiments, BFL is an interval in mm from the image side surfaces S19, S29, S39, S49, S59, S69, S79 of the fourth lenses L14, L24, L34, L44, L54, L64, L74 to the image planes IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, IMA7 along the optical axes OA1, OA2, OA3, OA4, OA5, OA6, OA7 respectively for the first to seventh embodiments, f is an effective focal length of the lens assemblies 1, 2, 3, 4, 5, 6, 7 for the first to seventh embodiments, f₄ is an effective focal length of the fourth lenses L14, L24, L34, L44, L54, L64, L74 for the first to seventh embodiments, SD1 is an optical effective diameter in mm of the first lens L11, L21, L31, L41, L51, L61, L71 for the first to seventh embodiments, SD4 is an optical effective diameter in mm of the fourth lens L14, L24, L34, L44, L54, L64, L74 for the first to seventh embodiments, SL1 is an interval in mm from the object side surface S11, S21, S31, S41, S51, S61, S71 of the first lenses L11, L21, L31, L41, L51, L61, L71 to the stop ST1, ST2, ST3, ST4, ST5, ST6, ST7 along the optical axis OA1, OA2, OA3, OA4, OA5, OA6, OA7 respectively for the first to seventh embodiments, and SL2 is an interval in mm from the stop ST1, ST2, ST3, ST4, ST5, ST6, ST7 to the image plane IMA1, IMA2, IMA3, IMA4, IMA5, IMA6, IMA7 along the optical axis OA1, OA2, OA3, OA4, OA5, OA6, OA7 respectively for the first to seventh embodiments. With the lens assemblies 1, 2, 3, 4, 5, 6, 7 satisfying at least one of the above conditions (1)-(8), the total length of lens assembly can be effectively decreased, the resolution can be effectively increased, the aberration can be effectively corrected, and the chromatic aberration can be effectively corrected. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies at least one of the conditions (1)-(8).

[0039] When the condition (1): −0.1≤R₁₁/R₄₂≤0.53 is satisfied, the manufacturability of the object side surface of the first lens can be effectively controlled, so that the system can effectively distribute the refractive power and reduce the sensitivity of the optical system. When the condition (2): 2≤TTL/SD4≤7 is satisfied, the total length of the lens assembly can be effectively control. When the condition (3): −10≤f4/BFL≤−3 is satisfied, the back focal length of the lens assembly can be effectively control. When the condition (4): 0≤SD4/TTL≤0.5 is satisfied, the total length of the lens assembly can be effectively control. When the condition (5): 0.05≤SL1/TTL≤0.5 is satisfied, the focal length of the lens assembly can be effectively control. When the condition (6): 0.1≤SD4/SL2≤0.8 is satisfied, the outer diameter of the lens assembly can be effectively control. When the condition (7): 0.1≤SD1/f≤0.6 is satisfied, the focal length of the lens assembly can be effectively control. When the condition (8): 19≤|f4/BFL|≤52 is satisfied, the back focal length of the lens assembly can be effectively control.

[0040] A detailed description of a lens assembly in accordance with a first embodiment of the invention is as follows. Referring to FIG. 1, the lens assembly 1 includes a first lens L11, a stop ST1, a second lens L12, a third lens L13, a fourth lens L14, and an optical filter OF1. The first lens L11, the stop ST1, the second lens L12, the third lens L13, the fourth lens L14 and the optical filter OF1 in order from an object side to an image side along an optical axis OA1. In operation, an image of light rays from the object side is formed at an image plane IMA1.

[0041] According to the foregoing, wherein: the second lens L12 is a biconcave lens, wherein the object side surface S14 is a concave surface; the fourth lens L14 is meniscus lens with negative refractive power, wherein the object side surface S18 is a convex surface and the image side surface S19 is a concave surface; both of the object side surface S110 and image side surface S111 of the optical filter OF1 are plane surfaces; the combined focal length of the second lens L12, the third lens L13 and the fourth lens L14 is −12.7753 mm. With the above design of the lenses and stop ST1 and at least any one of the conditions (1)-(7) satisfied, the lens assembly 1 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(7), refractive power distribution, and surface shape.

[0042] Table 1 shows the optical specification of the lens assembly 1 in FIG. 1.

[0043]

TABLE 1
Effective Focal Length = 16.625 mm
F-number = 3.32
Total Lens Length = 15.73 mm
Field of View = 23.78 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S11	4.147924847	1.45	1.62	64.0	8.2663	L11
S12	18.766751	0.419577542
S13	∞	1.470025991				ST1
S14	−24.52125773	0.401411229	1.67	19.2	−4.7659	L12
S15	3.743874668	0.777925908
S16	16.13529927	0.736419466	1.66	20.4	8.1015	L13
S17	−7.979545851	0.011641257
S18	24.12277307	0.4826548	1.54	56.1	−62.3982	L14
S19	13.92709675	0.875
S110	∞	0.21	1.52	64.2		OF1
S111	∞	8.703198374

[0044] The aspheric surface sag z of each aspheric lens in table 1 can be calculated by the following formula:

[0045] $z=c{h}^2/\left\{1+{\left[1-\left(k+1\right)c^2{h}^2\right]}^{1/2}\right\}+A{h}^4+B{h}^6+C{h}^8+D{h}^{10}+E{h}^{12}+F{h}^{14}+G{h}^9+H{h}^{10}+I{h}^{12}+J{h}^{14}+{\mathrm{Kh}}^{16}+L{h}^{18}+M{h}^{20}$
where c is curvature, h is the vertical distance from the lens surface to the optical axis, k is conic constant and A, B, C, D, E, F, G, H, I, J, K, L and M are aspheric coefficients. In the first embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 2.

[0046]

TABLE 2
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S11	−6.4439E−02	−6.1028E−04	2.6582E−04	−7.0752E−05	−1.4812E−06
	1.1649E−05	1.0701E−05	9.5655E−08	−2.9408E−06	−4.0063E−08
	6.5503E−08	5.3389E−09	−2.2559E−09	1.6934E−10
S12	2.7635E+01	1.1328E−04	−1.5418E−03	1.4107E−03	−5.6861E−04
	6.2714E−05	4.8673E−06	4.5209E−06	1.3297E−06	−5.2385E−07
	−4.1974E−08	1.2814E−08	4.3439E−09	−5.7953E−10
S14	8.8806E+01	1.1367E−02	3.9585E−04	−1.6455E−03	−4.4937E−04
	7.6910E−05	−2.4349E−04	1.8549E−04	1.1655E−04	2.3859E−05
	−5.6383E−06	−3.7304E−06	8.1173E−07	−5.2812E−08
S15	1.8372E+00	1.3320E−02	5.6190E−03	−2.5736E−03	−2.7673E−03
	−1.3329E−03	−6.6618E−05	3.0452E−04	1.8971E−04	−1.4237E−04
	4.1155E−04	−2.7058E−04	8.0516E−05	−9.9580E−06
S16	8.4570E+01	1.3477E−02	1.3161E−02	−1.4222E−03	−2.1761E−03
	−1.0022E−03	−5.2723E−04	−1.0959E−05	9.4134E−05	−2.4619E−06
	1.4194E−06	−7.0103E−07	4.2309E−06	−1.6412E−06
S17	−2.4254E−01	−4.3031E−03	4.8713E−03	4.7673E−04	−1.3216E−03
	−3.3130E−04	1.0799E−04	1.3808E−05	6.2631E−05	1.0138E−05
	−3.3335E−06	−8.2253E−06	−2.2555E−06	1.2735E−06
S18	−8.0799E+01	−3.4530E−02	−1.4439E−02	−4.8648E−03	2.6305E−03
	2.1583E−03	8.0278E−04	2.4471E−04	−7.9020E−05	−1.3095E−04
	−1.9250E−05	1.2869E−06	2.7392E−06	9.9292E−08
S19	−6.0394E+01	−1.4620E−02	−2.4514E−02	5.2519E−03	2.0567E−03
	4.2265E−04	2.1792E−04	5.3873E−05	−7.1093E−05	−7.2708E−05
	−4.2964E−06	4.2830E−06	4.6274E−06	−1.2618E−06

[0047] Table 3 shows the parameters and condition values for conditions (1)-(7) in accordance with the first embodiment of the invention. It can be seen from Table 3 that the lens assembly 1 of the first embodiment satisfies the conditions (1)-(7).

[0048]

TABLE 3
BFL	9.788 mm	SD1	5.000 mm	SD4	3.280 mm
SL1	1.870 mm	SL2	13.668 mm	f4/BFL	−6.375
R11/R42	0.298	TTL/SD4	4.738	SD4/SL2	0.240
SD4/TTL	0.211	SL1/TTL	0.120
SD1/f	0.301

[0049] By the above arrangements of the lenses and stop ST1, the lens assembly 1 of the first embodiment can meet the requirements of optical performance. It can be seen from FIG. 2A that the field curvature of tangential direction and sagittal direction in the lens assembly 1 of the first embodiment ranges from −0.10 mm to 0.30 mm. It can be seen from FIG. 2B that the distortion in the lens assembly 1 of the first embodiment ranges from 0% to 1%. It can be seen from FIG. 2C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 1 of the first embodiment ranges from 0.44 to 1.0. It is obvious that the field curvature and the distortion of the lens assembly 1 of the first embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 1 of the first embodiment is capable of good optical performance.

[0050] Referring to FIG. 3, FIG. 3 is a lens layout and optical path diagram of a lens assembly in accordance with a second embodiment of the invention. The lens assembly 2 includes a first lens L21, a stop ST2, a second lens L22, a third lens L23, a fourth lens L24, and an optical filter OF2. The first lens L21, the stop ST2, the second lens L22, the third lens L23, the fourth lens L24 and the optical filter OF2 in order from an object side to an image side along an optical axis OA2. In operation, an image of light rays from the object side is formed at an image plane IMA2.

[0051] According to the foregoing, wherein: the second lens L22 is a biconcave lens, wherein the object side surface S24 is a concave surface; the fourth lens L24 is meniscus lens with negative refractive power, wherein the object side surface S28 is a convex surface and the image side surface S29 is a concave surface; both of the object side surface S210 and image side surface S211 of the optical filter OF2 are plane surfaces; the combined focal length of the second lens L22, the third lens L23 and the fourth lens L24 is −12.7753 mm. With the above design of the lenses and stop ST2 and at least any one of the conditions (1)-(7) satisfied, the lens assembly 2 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(7), refractive power distribution, and surface shape.

[0052] Table 4 shows the optical specification of the lens assembly 2 in FIG. 3.

[0053]

TABLE 4
Effective Focal Length = 16.625 mm
F-number = 3.32
Total Lens Length = 15.730 mm
Field of View = 23.78 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S21	3.813960274	1.45	1.62	64.0	8.4788	L21
S22	11.84269497	0.419577542
S23	∞	1.470025991				ST2
S24	−39.79215657	0.3171875	1.67	19.2	−4.8804	L22
S25	3.61842274	0.757462017
S26	42.27487385	1.037295427	1.66	20.4	8.1476	L23
S27	−6.176825027	0.026247709
S28	12.13935081	0.456814034	1.54	56.1	−61.2600	L24
S29	8.750434221	0.875
S210	∞	0.21	1.52	64.2		OF2
S211	∞	8.710559045

[0054] The definition of aspheric surface sag z of each aspheric lens in table 4 is the same as that of in Table 1, and is not described here again. In the second embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 5.

[0055]

TABLE 5
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S21	1.1568E−01	7.59394E−05	6.21522E−05	7.27932E−05	1.00185E−06
	1.26804E−05	1.00727E−05	3.37085E−06	−1.99825E−06	1.78367E−07
	8.97075E−08	−5.95448E−10	−3.63108E−09	4.65048E−10
	2.2061E+01	4.6453E−04	−1.3465E−03	1.3093E−03	−5.7192E−04
	4.7498E−05	1.6454E−05	8.9817E−06	4.0953E−06	−4.4634E−07
	−2.9007E−07	−8.5501E−10	1.6589E−08	−1.4402E−09
S24	4.0992E+01	5.9955E−04	8.4063E−04	7.4190E−04	1.0141E−03
	4.2098E−04	−3.1647E−04	−2.6385E−05	−2.8861E−05	−5.4869E−07
	6.1563E−06	−1.2818E−06	1.2473E−07	5.7491E−09
S25	2.0780E+00	−1.9316E−04	−1.5431E−04	1.2021E−03	7.8417E−04
	1.6881E−04	−4.9117E−05	−1.2150E−06	−3.5902E−05	3.4928E−05
	−4.8214E−06	−5.0362E−06	−8.5000E−07	7.2681E−07
S26	4.1167E+02	2.8879E−04	1.3475E−02	−1.5414E−03	−1.1485E−03
	1.7690E−04	1.1741E−04	2.4233E−04	1.1892E−04	−1.3802E−05
	−5.0989E−06	−2.1514E−06	7.7666E−07	−7.2672E−08
S27	−2.5558E+01	−8.5443E−03	2.6354E−03	−9.7250E−04	−1.4540E−03
	−7.8403E−05	3.4522E−04	1.8306E−04	1.3970E−04	2.1228E−05
	−8.1422E−06	−1.9512E−06	1.7297E−06	−4.3062E−07
S28	−2.6311E−01	−2.2842E−02	−1.8202E−02	−9.5410E−03	2.8426E−04
	1.1063E−03	3.5966E−04	1.5762E−04	−1.5616E−05	−9.8583E−06
	2.4486E−05	−3.6625E−06	−5.0095E−06	1.2185E−06
S29	−5.2721E+01	−1.0049E−02	−2.7447E−02	1.0048E−03	−5.1940E−05
	−6.5488E−05	3.1896E−04	2.5273E−04	2.2384E−05	−5.6656E−05
	−1.6450E−05	−4.0254E−07	4.3788E−06	−8.1999E−07

[0056] Table 6 shows the parameters and condition values for conditions (1)-(7) in accordance with the second embodiment of the invention. It can be seen from Table 6 that the lens assembly 2 of the second embodiment satisfies the conditions (1)-(7).

[0057]

TABLE 6
BFL	9.796 mm	SD1	5.000 mm	SD4	3.184 mm
SL1	1.870 mm	SL2	13.861 mm	f4/BFL	−6.370
R11/R42	0.436	TTL/SD4	4.941	SD4/SL2	0.230
SD4/TTL	0.202	SL1/TTL	0.119
SD1/f	0.301

[0058] By the above arrangements of the lenses and stop ST2, the lens assembly 2 of the second embodiment can meet the requirements of optical performance. It can be seen from FIG. 4A that the field curvature of tangential direction and sagittal direction in the lens assembly 2 of the second embodiment ranges from 0 mm to 0.2 mm. It can be seen from FIG. 4B that the distortion in the lens assembly 2 of the second embodiment ranges from 0% to 0.2%. It can be seen from FIG. 4C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 2 of the second embodiment ranges from 0.50 to 1.0. It is obvious that the field curvature and the distortion of the lens assembly 2 of the second embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 2 of the second embodiment is capable of good optical performance.

[0059] Referring to FIG. 5, FIG. 5 is a lens layout and optical path diagram of a lens assembly in accordance with a third embodiment of the invention. The lens assembly 3 includes a first lens L31, a stop ST3, a second lens L32, a third lens L33, a fourth lens L34, and an optical filter OF3. The first lens L31, the stop ST3, the second lens L32, the third lens L33, the fourth lens L34 and the optical filter OF3 in order from an object side to an image side along an optical axis OA3. In operation, an image of light rays from the object side is formed at an image plane IMA3.

[0060] According to the foregoing, wherein: the second lens L32 is a biconcave lens, wherein the object side surface S34 is a concave surface; the fourth lens L34 is meniscus lens with negative refractive power, wherein the object side surface S38 is a convex surface and the image side surface S39 is a concave surface; both of the object side surface S310 and image side surface S311 of the optical filter OF3 are plane surfaces; the combined focal length of the second lens L32, the third lens L33 and the fourth lens L34 is −13.9197 mm. With the above design of the lenses and stop ST3 and at least any one of the conditions (1)-(7) satisfied, the lens assembly 3 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(7), refractive power distribution, and surface shape.

[0061] Table 7 shows the optical specification of the lens assembly 3 in FIG. 5.

[0062]

TABLE 7
Effective Focal Length = 16.625 mm
F-number = 3.32
Total Lens Length = 15.573 mm
Field of View = 23.78 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S31	4.014074097	1.45	1.62	64.0	8.5318	L31
S32	14.30015395	0.419577542
S33	∞	1.470025991				ST3
S34	−121.6390606	0.240453499	1.67	19.2	−5.0282	L32
S35	3.508147432	0.906434386
S36	21.0313572	0.573724036	1.66	20.4	8.6742	L33
S37	−7.897197038	0.011641257
S38	19.19107249	0.694820162	1.54	56.1	−89.1370	L34
S39	13.52521668	0.875
S310	∞	0.21	1.52	64.2		OF3
S311	∞	8.721678988

[0063] The definition of aspheric surface sag z of each aspheric lens in table 7 is the same as that of in Table 1, and is not described here again. In the third embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 8.

[0064]

TABLE 8
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S31	5.6845E−03	−4.1268E−04	1.3443E−04	−4.5531E−05	−1.2413E−05
	7.7148E−06	1.0746E−05	5.8031E−07	−2.6496E−06	−3.9125E−08
	5.2434E−08	3.4365E−09	−1.7121E−09	1.3046E−10
S32	2.5310E+01	−1.2028E−04	−1.7237E−03	1.3102E−03	−5.8602E−04
	3.8176E−05	4.9242E−06	7.3206E−06	1.9137E−06	−1.0872E−06
	−1.0494E−07	2.1320E−08	7.6734E−09	−1.1071E−09
S34	2.0227E+02	3.6229E−03	−2.3867E−04	−8.4909E−04	2.8135E−04
	1.9142E−04	−3.7413E−04	9.1843E−05	6.1110E−05	2.2515E−05
	5.7992E−06	−3.1268E−06	−2.2804E−07	5.3462E−08
S35	1.7154E+00	4.3386E−03	9.3395E−04	−1.0614E−03	−1.0215E−03
	−6.3166E−04	−1.9744E−04	6.3308E−05	7.2564E−06	−1.5621E−04
	4.1678E−04	−2.7090E−04	8.2877E−05	−1.0279E−05
S36	1.3770E+02	9.0351E−03	1.5276E−02	−5.5244E−04	−1.7848E−03
	−7.6205E−04	−4.2334E−04	4.4481E−05	1.0216E−04	−6.8774E−06
	−1.4242E−05	−2.0318E−06	4.9714E−06	−8.4437E−07
S37	−3.6267E+01	−3.8818E−03	4.8847E−03	1.3861E−04	−7.6840E−04
	1.0554E−04	2.1799E−04	−9.1986E−05	−6.2992E−05	1.5900E−06
	6.4387E−06	−4.3853E−06	−3.0148E−06	1.7193E−06
S38	4.7276E+01	−2.1866E−02	−1.3152E−02	−5.8362E−03	1.6216E−03
	1.5979E−03	6.2093E−04	2.1727E−04	−5.1118E−05	−1.0901E−04
	−1.4536E−05	1.9058E−06	3.3034E−06	−1.0583E−07
S39	−2.6060E+01	−5.9842E−03	−2.2870E−02	4.5682E−03	1.2814E−03
	1.1750E−04	1.5357E−04	4.7650E−05	−6.0253E−05	−4.0645E−05
	2.5165E−06	1.4501E−06	2.5557E−06	−7.5700E−07

[0065] Table 9 shows the parameters and condition values for conditions (1)-(7) in accordance with the third embodiment of the invention. It can be seen from Table 9 that the lens assembly 3 of the third embodiment satisfies the conditions (1)-(7).

[0066]

TABLE 9
BFL	9.807 mm	SD1	5.000 mm	SD4	3.294 mm
SL1	1.870 mm	SL2	13.704 mm	f4/BFL	−9.089
R11/R42	0.297	TTL/SD4	4.728	SD4/SL2	0.240
SD4/TTL	0.212	SL1/TTL	0.120
SD1/f	0.301

[0067] By the above arrangements of the lenses and stop ST3, the lens assembly 3 of the third embodiment can meet the requirements of optical performance. It can be seen from FIG. 6A that the field curvature of tangential direction and sagittal direction in the lens assembly 3 of the third embodiment ranges from −0.2 mm to 0.2 mm. It can be seen from FIG. 6B that the distortion in the lens assembly 3 of the third embodiment ranges from −0.1% to 0.6%. It can be seen from FIG. 6C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 3 of the third embodiment ranges from 0.47 to 1.0. It is obvious that the field curvature and the distortion of the lens assembly 3 of the third embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 3 of the third embodiment is capable of good optical performance.

[0068] Referring to FIG. 7, FIG. 7 is a lens layout and optical path diagram of a lens assembly in accordance with a fourth embodiment of the invention. The lens assembly 4 includes a first lens L41, a stop ST4, a second lens L42, a third lens L43, a fourth lens L44, and an optical filter OF4. The first lens L41, the stop ST4, the second lens L42, the third lens L43, the fourth lens L44 and the optical filter OF4 in order from an object side to an image side along an optical axis OA4. In operation, an image of light rays from the object side is formed at an image plane IMA4.

[0069] According to the foregoing, wherein: the second lens L42 is a biconcave lens, wherein the object side surface S44 is a concave surface; the fourth lens L44 is meniscus lens with negative refractive power, wherein the object side surface S48 is a convex surface and the image side surface is a concave surface; both of the object side surface S410 and image side surface S411 of the optical filter OF4 are plane surfaces. With the above design of the lenses and stop ST4 and at least any one of the conditions (1)-(2) and (4)-(8) satisfied, the lens assembly 4 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(2) and (4)-(8), refractive power distribution, and surface shape.

[0070] Table 10 shows the optical specification of the lens assembly 4 in FIG. 7.

[0071]

TABLE 10
Effective Focal Length = 19.004 mm
F-number = 3.5
Total Lens Length = 18.413 mm
Field of View = 24.92 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S41	4.862303	2.005002	1.61882	63.9702	10.8327	L41
S42	14.91226	0.533518
S43	∞	1.695911				ST4
S44	−39.20089	0.356998	1.67134	19.2429	−5.5755	L42
S45	4.153289	0.8509787
S46	39.84778	0.8200016	1.66134	20.3729	9.0794	L43
S47	−7.012064	0.02987472
S48	9.731521	0.7900134	1.535218	56.11525	−588.3360	L44
S49	9.172624	1
S410	∞	0.21	1.5168	64.1673		OF4
S411	∞	10.12045

[0072] The definition of aspheric surface sag z of each aspheric lens in table 10 is the same as that of in Table 1, and is not described here again. In the fourth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 11.

[0073]

TABLE 11
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S41	5.6502E−02	−3.1144E−04	1.8015E−04	3.1911E−05	−1.1754E−05
	9.2394E−07	1.6729E−06	−7.1104E−07	1.3481E−07	4.4131E−08
	2.7576E−09	−1.2525E−10	−4.8723E−11	4.6764E−12
S42	2.7193E+01	−3.6006E−04	−2.6114E−04	1.5364E−04	−4.6599E−05
	−2.9280E−05	9.3770E−07	−6.2727E−07	9.8014E−07	1.7668E−07
	1.7728E−08	−3.3388E−09	−4.8516E−10	3.8766E−11
S44	4.4808E+01	1.3275E−03	1.4437E−03	−5.6809E−04	3.3209E−04
	4.0309E−04	−2.4793E−04	1.1275E−04	−1.3636E−05	−3.9089E−06
	7.5107E−06	−1.0898E−06	−2.7394E−07	4.7751E−08
S45	1.8511E+00	7.2453E−04	1.6300E−03	−6.3170E−04	1.1079E−06
	−1.9745E−05	7.1495E−05	1.3139E−05	−4.2817E−05	8.4233E−06
	7.1653E−06	1.0573E−06	1.2241E−07	−1.3044E−07
S46	2.0832E+02	3.4682E−04	1.0845E−02	−9.4297E−04	−1.1616E−03
	−1.0352E−04	−1.5378E−04	2.5266E−05	2.2399E−06	−3.6479E−05
	3.6138E−06	1.7273E−06	6.0232E−07	−1.3862E−07
S47	−3.1197E+01	−3.1330E−03	1.8500E−03	−2.9123E−03	−5.8295E−04
	2.7860E−04	2.4518E−04	−5.0758E−05	−6.4562E−05	−8.6034E−06
	5.3197E−07	1.2721E−06	2.2354E−07	−5.4182E−08
S48	2.0083E+01	−3.9651E−03	−1.0141E−02	−4.4530E−03	−2.6601E−04
	2.9207E−04	2.0502E−04	1.7997E−04	6.6924E−05	−3.8734E−05
	1.7414E−06	−9.2815E−07	9.4106E−07	−1.5638E−07
S49	2.5184E+00	8.9647E−04	−1.8705E−02	1.8684E−03	9.4654E−04
	4.6361E−05	−5.3598E−06	9.5479E−06	1.7200E−05	2.4068E−07
	−8.4141E−07	9.5479E−06	1.7200E−05	2.4068E−07	−8.4141E−07

[0074] Table 12 shows the parameters and condition values for conditions (1)-(2) and (4)-(8) in accordance with the fourth embodiment of the invention. It can be seen from Table 12 that the lens assembly 4 of the fourth embodiment satisfies the conditions (1)-(2) and (4)-(8).

[0075]

TABLE 12
BFL	11.330 mm	SD1	5.480 mm	SD4	4.023 mm
SL1	2.539 mm	SL2	15.874 mm	|f4/BFL|	51.925
R11/R42	0.530	TTL/SD4	4.577	SD4/SL2	0.253
SD4/TTL	0.219	SL1/TTL	0.138
SD1/f	0.288

[0076] By the above arrangements of the lenses and stop ST4, the lens assembly 4 of the fourth embodiment can meet the requirements of optical performance. It can be seen from FIG. 8A that the field curvature of tangential direction and sagittal direction in the lens assembly 4 of the fourth embodiment ranges from −0.06 mm to 0.1 mm. It can be seen from FIG. 8B that the distortion in the lens assembly 4 of the fourth embodiment ranges from 0% to 0.4%. It can be seen from FIG. 8C that the modulation transfer function of tangential direction and sagittal direction in the lens assembly 4 of the fourth embodiment ranges from 0.59 to 1.0. It is obvious that the field curvature and the distortion of the lens assembly 4 of the fourth embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 4 of the fourth embodiment is capable of good optical performance.

[0077] Referring to FIG. 9, FIG. 9 is a lens layout and optical path diagram of a lens assembly in accordance with a fifth embodiment of the invention. The lens assembly 5 includes a first lens L51, a stop ST5, a second lens L52, a third lens L53, a fourth lens L54, and an optical filter OF5. The first lens L51, the stop ST5, the second lens L52, the third lens L53, the fourth lens L54 and the optical filter OF5 in order from an object side to an image side along an optical axis OA5. In operation, an image of light rays from the object side is formed at an image plane IMA5.

[0078] According to the foregoing, wherein: the second lens L52 is a biconcave lens, wherein the object side surface S54 is a concave surface; the fourth lens L54 is meniscus lens with negative refractive power, wherein the object side surface S58 is a convex surface and the image side surface S59 is a concave surface; both of the object side surface S510 and image side surface S511 of the optical filter OF5 are plane surfaces. With the above design of the lenses and stop ST5 and at least any one of the conditions (1)-(2) and (4)-(8) satisfied, the lens assembly 5 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(2) and (4)-(8), refractive power distribution, and surface shape.

[0079] Table 13 shows the optical specification of the lens assembly 5 in FIG. 9.

[0080]

TABLE 13
Effective Focal Length = 19.004 mm
F-number = 3.5
Total Lens Length = 18.019 mm
Field of View = 24.9 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S51	4.658756	2.001204	1.618821	63.9702	10.2068	L51
S52	14.83857	1.446789
S53	∞	0.8847622				ST5
S54	−23.66561	0.3153428	1.671339	19.24289	−5.5372	L52
S55	4.433643	1.183656
S56	24.08284	0.5896945	1.661342	20.3729	9.5159	L53
S57	−8.436482	0.02785689
S58	25.02732	0.8035841	1.535218	56.11525	−214.5216	L54
S59	20 31824	1
S510	∞	0.21	1.5168	64.16734		OF5
S511	∞	9.556519

[0081] The definition of aspheric surface sag z of each aspheric lens in table 13 is the same as that of in Table 1, and is not described here again. In the fifth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 14.

[0082]

TABLE 14
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S51	1.0255E−01	−2.6780E−04	2.9565E−04	5.5125E−05	−1.0145E−05
	3.0419E−06	2.6067E−06	−4.3341E−07	2.8284E−07	4.4157E−08
	7.6556E−10	−2.8754E−10	−4.9527E−11	9.0773E−12
S52	2.8316E+01	1.7060E−04	−1.4465E−04	2.1662E−04	−3.8711E−06
	−1.9914E−05	−3.8875E−07	−1.5330E−06	6.0678E−07	1.7687E−07
	2.3899E−08	−4.5410E−09	−8.5861E−10	1.1735E−10
S54	−1.1289E+02	4.9341E−04	2.5648E−03	−3.8603E−04	−3.0295E−05
	−1.4741E−05	−2.0980E−05	1.9537E−05	8.5220E−06	3.4167E−06
	1.1768E−06	−7.3783E−08	3.9915E−08	−2.4403E−08
	1.9303E+00	7.6798E−04	1.6760E−03	−4.9545E−04	−9.9088E−06
	−3.9671E−05	5.3248E−05	1.2455E−06	−5.0154E−05	6.6032E−06
	6.3450E−06	7.6143E−07	8.4974E−08	−1.0523E−07
S56	6.2749E+01	9.5873E−04	4.0627E−03	5.8636E−04	6.0669E−06
	−8.6715E−05	−7.6869E−05	−4.4395E−05	−2.0192E−05	−3.1304E−06
	2.8350E−07	4.4799E−07	2.5523E−07	−3.5680E−08
S57	−3.0995E+01	−7.4940E−04	5.2298E−04	−9.8916E−04	−3.4566E−04
	−1.3892E−04	1.4444E−04	−4.1720E−09	−2.1442E−06	−5.6984E−06
	5.7758E−07	5.9329E−07	1.0359E−07	−2.0627E−08
S58	9.8185E+01	−2.6131E−03	−5.9887E−03	−2.8377E−03	−7.5943E−04
	8.7394E−05	3.1844E−05	7.6035E−05	6.3013E−05	9.4338E−06
	7.7322E−07	−5.6148E−07	−7.5735E−08	5.7612E−09
S59	5.3587E+01	−3.1248E−03	−8.5776E−03	−3.8794E−04	−1.3506E−04
	7.1447E−06	1.3901E−04	3.8886E−09	5.4843E−06	5.5783E−07
	1.0728E−07	1.4258E−07	−1.0444E−07	1.1266E−08

[0083] Table 15 shows the parameters and condition values for conditions (1)-(2) and (4)-(8) in accordance with the fifth embodiment of the invention. It can be seen from Table 15 that the lens assembly 5 of the fifth embodiment satisfies the conditions (1)-(2) and (4)-(8).

[0084]

TABLE 15
BFL	10.767 mm	SD1	5.449 mm	SD4	4.180 mm
SL1	3.448 mm	SL2	14.571 mm	|f4/BFL|	19.925
R11/R42	0.229	TTL/SD4	4.310	SD4/SL2	0.287
SD4/TTL	0.232	SL1/TTL	0.191
SD1/f	0.287

[0085] By the above arrangements of the lenses and stop ST5, the lens assembly 5 of the fifth embodiment can meet the requirements of optical performance. The field curvature diagram (figure is omitted), distortion diagram (figure is omitted), and modulation transfer function diagram are similar to those of the lens assembly 4 of the fourth embodiment, and is not described here again. The field curvature and the distortion of the lens assembly 5 of the fifth embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 5 of the fifth embodiment is capable of good optical performance.

[0086] Referring to FIG. 10, FIG. 10 is a lens layout and optical path diagram of a lens assembly in accordance with a sixth embodiment of the invention. The lens assembly 6 includes a first lens L61, a stop ST6, a second lens L62, a third lens L63, a fourth lens L64, and an optical filter OF6. The first lens L61, the stop ST6, the second lens L62, the third lens L63, the fourth lens L64 and the optical filter OF6 in order from an object side to an image side along an optical axis OA6. In operation, an image of light rays from the object side is formed at an image plane IMA6.

[0087] According to the foregoing, wherein: the second lens L62 is a biconcave lens, wherein the object side surface S64 is a concave surface; the fourth lens L64 is meniscus lens with positive refractive power, wherein the object side surface S68 is a convex surface and the image side surface S69 is a concave surface; both of the object side surface S610 and image side surface S611 of the optical filter OF6 are plane surfaces. With the above design of the lenses and stop ST6 and at least any one of the conditions (1)-(2) and (4)-(8) satisfied, the lens assembly 6 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(2) and (4)-(8), refractive power distribution, and surface shape.

[0088] Table 16 shows the optical specification of the lens assembly 6 in FIG. 10.

[0089]

TABLE 16
Effective Focal Length = 19.004 mm
F-number = 3.5
Total Lens Length = 18.719 mm
Field of View = 24.92 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S61	4.930945	1.802757	1.61882	63.9702	10.9297	L61
S62	15.65543	0.6253327
S63	∞	1.905133				ST6
S64	−21.67255	0.3457092	1.67134	19.2429	−5.2665	L62
S65	4.251909	0.8250904
S66	17.99141	0.8341204	1.66134	20.3729	8.6375	L63
S67	−8.215247	0.02988168
S68	32.09524	0.9483538	1.535218	56.11525	234.8734	L64
S69	42.6551	1
S610	∞	0.21	1.5168	64.1673		OF6
S611	∞	10.19215

[0090] The definition of aspheric surface sag z of each aspheric lens in table 16 is the same as that of in Table 1, and is not described here again. In the sixth embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 17.

[0091]

TABLE 17
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S61	5.8181E−02	9.1428E−05	2.0528E−04	6.3571E−05	3.7852E−06
	6.8774E−06	4.0106E−06	−4.8515E−07	2.1255E−07	1.5598E−08
	1.2623E−09	1.7219E−10	−1.0704E−11	2.7090E−12
S62	2.9425E+01	3.7300E−04	−9.3965E−05	1.7343E−04	8.0017E−06
	−4.0938E−06	3.0371E−06	3.2751E−07	2.0157E−07	−8.0629E−09
	7.4967E−09	6.1288E−10	5.3578E−11	−6.6780E−12
S64	−1.0042E+02	5.6685E−04	2.6883E−03	−3.2772E−05	5.9894E−05
	1.4417E−05	−2.9555E−05	1.3302E−05	5.7457E−06	2.6180E−06
	5.5104E−07	−2.1653E−08	4.2175E−08	−1.5305E−08
S65	1.3041E+00	1.1673E−03	2.0880E−03	−1.7585E−04	7.3861E−05
	−2.1378E−06	6.5941E−05	−2.6561E−06	−5.8163E−05	3.4333E−06
	5.2013E−06	6.1319E−07	1.2995E−07	−5.7323E−08
S66	7.2287E+01	8.5506E−04	3.7186E−03	1.9030E−04	−1.3171E−04
	−1.0275E−04	−7.4692E−05	−4.7238E−05	−2.0228E−05	−3.8962E−06
	6.1189E−08	2.2142E−07	1.8275E−07	−1.7209E−08
S67	−2.3911E+01	−1.4762E−03	3.7224E−04	−6.7625E−04	−2.9035E−04
	−1.4439E−04	1.2077E−04	−4.8328E−06	−5.1068E−06	−4.5846E−06
	6.4126E−07	3.2261E−07	4.2213E−08	6.5788E−11
S68	1.7891E+02	−3.7440E−03	−5.4739E−03	−2.5887E−03	−6.0866E−04
	1.7134E−04	3.0421E−05	5.0169E−05	4.4813E−05	2.7419E−06
	1.0579E−07	−1.2582E−07	1.0724E−07	−2.1866E−08
S69	1.0361E+02	−2.3090E−03	−7.9231E−03	−1.9599E−04	−1.2056E−04
	6.9505E−06	1.2609E−04	−6.7574E−06	4.0361E−06	−6.9351E−07
	7.6363E−08	1.7736E−07	−7.1158E−08	7.4292E−09

[0092] Table 18 shows the parameters and condition values for conditions (1)-(2) and (4)-(8) in accordance with the sixth embodiment of the invention. It can be seen from Table 18 that the lens assembly 6 of the sixth embodiment satisfies the conditions (1)-(2) and (4)-(8).

[0093]

TABLE 18
BFL	11.402 mm	SD1	5.420 mm	SD4	4.000 mm
SL1	2.428 mm	SL2	16.290 mm	|f4/BFL|	20.599
R11/R42	0.116	TTL/SD4	4.680	SD4/SL2	0.246
SD4/TTL	0.214	SL1/TTL	0.130
SD1/f	0.285

[0094] The field curvature diagram (figure is omitted), distortion diagram (figure is omitted), and modulation transfer function diagram are similar to those of the lens assembly 4 of the fourth embodiment, and is not described here again. The field curvature and the distortion of the lens assembly 6 of the sixth embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 6 of the sixth embodiment is capable of good optical performance.

[0095] Referring to FIG. 11, FIG. 11 is a lens layout and optical path diagram of a lens assembly in accordance with a seventh embodiment of the invention. The lens assembly 7 includes a first lens L71, a stop ST7, a second lens L72, a third lens L73, a fourth lens L74, and an optical filter OF7. The first lens L71, the stop ST7, the second lens L72, the third lens L73, the fourth lens L74 and the optical filter OF7 in order from an object side to an image side along an optical axis OA7. In operation, an image of light rays from the object side is formed at an image plane IMA7.

[0096] According to the foregoing, wherein: the second lens L72 is a meniscus lens, wherein the object side surface S74 is a convex surface; the fourth lens L74 is meniscus lens with negative refractive power, wherein the object side surface S78 is a concave surface and the image side surface S79 is a convex surface; both of the object side surface S710 and image side surface S711 of the optical filter OF7 are plane surfaces. With the above design of the lenses and stop ST7 and at least any one of the conditions (1)-(7) satisfied, the lens assembly 7 can have an effective decreased the total length, an effective increased resolution, an effective corrected aberration, and is capable of an effective corrected chromatic aberration. The preferred embodiment of the present invention can be achieved when the lens assembly satisfies conditions (1)-(7), refractive power distribution, and surface shape.

[0097] Table 19 shows the optical specification of the lens assembly 7 in FIG. 11.

[0098]

TABLE 19
Effective Focal Length = 19.000 mm
F-number = 3.26
Total Lens Length = 17.491 mm
Field of View = 24.92 degrees
	Radius of				Effective
Surface	Curvature	Thickness			Focal Length
Number	(mm)	(mm)	Nd	Vd	(mm)	Remark
S71	4.603334	1.665403	1.61882	63.97	9.5887	L71
S72	17.6924	1.634952
S73	∞	0.2878805				ST7
S74	28.51346	0.8724314	1.67134	19.2429	−7.2576	L72
S75	4.110099	1.325426
S76	29.54656	0.9937444	1.66134	20.3729	12.1832	L73
S77	−10.93001	0.03102059
S78	−18.28981	0.6914978	1.535218	56.11525	−35.6119	L74
S79	−458.5162	5
S710	∞	0.21	1.5168	64.1673		OF7
S711	∞	4.778369

[0099] The definition of aspheric surface sag z of each aspheric lens in table 19 is the same as that of in Table 1, and is not described here again. In the seventh embodiment, the conic constant k and the aspheric coefficients A, B, C, D, E, F, G, H, I, J, K, L, M of each aspheric surface are shown in Table 20.

[0100]

TABLE 20
	k	A	B	C
Surface	E	F	G	H	D
Number	J	K	L	M	I
S71	−3.9466E−02	−1.5617E−04	4.8547E−05	1.1216E−05	−2.2263E−05
	−5.3052E−07	2.3208E−06	−6.8696E−08	5.7059E−08	−2.9175E−09
	−9.7170E−11	−7.5715E−11	−1.3791E−12	5.0736E−13
S72	3.6942E+00	2.8752E−04	−5.7361E−04	2.8270E−05	−3.9084E−06
	−1.2515E−06	1.7173E−06	−4.4491E−07	−6.5370E−08	−1.0027E−08
	−4.3862E−09	7.6404E−11	−7.0025E−12	1.2426E−12
S74	8.8810E+00	1.7047E−03	3.6065E−03	5.9940E−04	1.7482E−04
	−1.1289E−05	−6.3916E−05	−4.2999E−06	−5.4855E−06	1.4946E−06
	2.5427E−07	−2.6561E−08	−9.8753E−09	8.9703E−10
S75	4.4143E−01	2.0377E−03	5.0643E−03	4.5812E−04	3.9088E−04
	2.1547E−04	1.7013E−04	2.7789E−05	−7.0524E−05	−1.0736E−05
	1.2553E−06	7.8489E−07	5.1094E−07	−1.3359E−07
S76	−3.2588E+00	3.7643E−04	9.0616E−04	−1.4999E−04	1.4334E−04
	1.0956E−04	3.3362E−05	−1.3386E−05	−1.2696E−05	−3.5547E−06
	−4.3561E−07	2.0387E−08	8.6874E−08	−2.0583E−09
S77	−1.1169E+01	−2.8420E−03	9.1916E−04	−4.7952E−04	−2.0948E−04
	−1.3730E−04	1.0766E−04	1.3112E−06	−2.0570E−06	−4.2451E−06
	−9.8280E−08	6.7275E−08	3.8943E−08	1.2244E−08
S78	0.0000E+00	−4.5203E−03	−3.5459E−03	−6.0157E−04	1.1676E−05
	6.2102E−05	−6.7696E−05	5.3231E−06	3.7127E−05	6.7016E−06
	5.2312E−07	−3.7380E−07	3.9420E−11	1.8754E−08
S79	0.0000E+00	−3.8860E−03	−5.8373E−03	−1.1122E−04	−1.9613E−04
	1.4878E−07	1.4336E−04	3.4756E−06	8.6135E−06	−2.6390E−06
	−3.1311E−07	2.2168E−07	−1.2683E−08	−2.1240E−09

[0101] Table 21 shows the parameters and condition values for conditions (1)-(7) in accordance with the seventh embodiment of the invention. It can be seen from Table 21 that the lens assembly 7 of the seventh embodiment satisfies the conditions (1)-(7).

[0102]

TABLE 21
BFL	9.988 mm	SD1	9.340 mm	SD4	8.426 mm
SL1	3.300 mm	SL2	14.190 mm	f4/BFL	−3.565
R11/R42	−0.010	TTL/SD4	2.076	SD4/SL2	0.594
SD4/TTL	0.482	SL1/TTL	0.189
SD1/f	0.491

[0103] The field curvature diagram (figure is omitted), distortion diagram (figure is omitted), and modulation transfer function diagram are similar to those of the lens assembly 4 of the fourth embodiment, and is not described here again. The field curvature and the distortion of the lens assembly 7 of the seventh embodiment can be corrected effectively, and the image resolution can meet the requirement. Therefore, the lens assembly 7 of the seventh embodiment is capable of good optical performance.

[0104] In the above embodiments, one glass lens and three plastic lenses are used for thinning, maintaining high resolution, and process processing.

[0105] While the invention has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.