Photographing optical lens assembly

This invention provides a photographing optical lens assembly including, in order from an object side toward 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 concave object-side surface and a concave image-side surface, a third lens element with positive refractive power, a fourth lens element with negative refractive power having a convex object-side surface and a concave image-side surface, and at least one of surfaces thereof being aspheric, a plastic fifth lens element having a convex object-side surface and a concave image-side surface with at least one inflection point. An aperture stop is positioned between an imaged object and the third lens element. The photographing optical lens assembly further comprises an electronic sensor on which the object is imaged.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 099112822 filed in Taiwan, R.O.C. on Apr. 23, 2010, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a photographing optical lens assembly, and more particularly, to a compact photographing optical lens assembly used in portable electronic devices.

2. Description of the Prior Art

In recent years, with the popularity of mobile phone cameras, the demand for compact imaging lenses is increasing, and the sensor of a general photographing camera is none other than CCD (charge coupled device) or CMOS device (Complementary Metal Oxide Semiconductor device). Furthermore, as advanced semiconductor manufacturing technology has allowed the pixel size of sensors to be reduced and the resolution of compact imaging lenses has gradually increased, there is an increasing demand for compact imaging lenses featuring better image quality.

A conventional compact photographing optical lens assembly for mobile electronics, such as the one disclosed in U.S. Pat. No. 7,365,920, generally comprises four lens elements, wherein two spherical-surface glass lenses are used as the first and second lens elements, and being adhered together to form a doublet and thereby to correct the chromatic aberration. Such an arrangement of optical elements, however, has the following disadvantages: (1) the freedom of the system is curtailed due to the employment of excess number of spherical-surface glass lenses, thus the total track length of the system cannot be reduced easily; (2) the process of making the glass lenses adhered together is complicated, posing difficulties in manufacture. In addition, a four independent lens elements optical system is disclosed by U.S. Pat. No. 7,643,225, comprising multiple aspheric lens elements, which effectively shortens the total track length and obtains high image quality.

However, due to the popularity of high standard mobile devices such as smart phones and PDAs (Personal Digital Assistant) driving the rapid improvements in high resolution and image quality of the compact imaging lens systems, conventional four lens elements systems no longer satisfy the higher level camera modules. Furthermore, with the current trend for high performance and compact design in electronic products, the need for high resolution and high performance compact photographing optical lens assembly is very crucial in high level electronics development.

Therefore, a need exists in the art for a photographing optical lens assembly that features better image quality, maintains a moderate total track length and is applicable to compact portable electronic products.

SUMMARY OF THE INVENTION

The present invention provides a photographing 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 concave object-side surface and a concave image-side surface; a third lens element with positive refractive power; a fourth lens element with negative refractive power having a convex image-side surface and a concave image-side surface, at least one of the object-side and image-side surfaces thereof being aspheric; and a fifth lens element having a convex object-side surface and a concave image-side surface, at least one inflection point formed on the image-side surface, made of plastic; wherein the photographing optical lens assembly further comprises an aperture stop and an electronic sensor for image formation, wherein the aperture stop is disposed between the imaged object and the third lens element; wherein the first lens element of the photographing optical lens assembly is closest to the object, and there are at most six lens elements with refractive power in the photographing optical lens assembly; and wherein the radius of curvature on the image-side surface of the second lens element is R4, the focal length of the photographing optical lens assembly is f, the Abbe number of the first lens element is V1, the Abbe number of the second lens element is V2, the distance on the optical axis between the aperture stop and the electronic sensor is SL, the distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, and they satisfy the relation:
0.3<R4/f<30.0;
23.0<V1-V2<45.0;
0.65<SL/TTL<1.10

According to another aspect of the present invention, a photographing optical lens assembly comprises, 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 concave object-side surface and a concave image-side surface; a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a fourth lens element with negative refractive power, at least one of the object-side and image-side surfaces thereof being aspheric; a fifth lens element having a convex object-side surface and a concave image-side surface, the object-side and image-side surfaces thereof being aspheric; wherein the photographing optical lens assembly further comprises an aperture stop and an electronic sensor for image formation, and the aperture stop is disposed between the imaged object and the third lens element; wherein there are five lens elements with refractive power in the photographing optical lens assembly; wherein the radius of curvature on the image-side surface of the second lens element is R4, the focal length of the photographing optical lens assembly is f, the distance on the optical axis between the first lens element and the second lens element is T12, the distance on the optical axis between the aperture stop and the electronic sensor is SL, the distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, and they satisfy the relation:
0.3<R4/f<30.0;
0.5<(T12/f)*100<15.0;
0.65<SL/TTL<1.10

Such an arrangement of optical elements can reduce the size as well as the sensitivity of the optical system and obtain higher resolution.

In the present photographing optical lens assembly, the first lens element has positive refractive power supplying a portion of total refractive power needed in the system, which reduces the total track length of the photographing optical lens assembly; the second lens element has negative refractive power so that the aberration generated from the positive refractive power of the first lens element and the chromatic aberration of the system can be favorably corrected; the third lens element has positive refractive power, which effectively distributes the refractive power of the first lens element and reduces the sensitivity of the system; the fourth lens element having negative refractive power along with the third lens element can form the one-positive-one-negative telephoto structure, which effectively reduces the total track length of the photographing optical lens assembly; the fifth lens element can have positive or negative refractive power, which functions as a corrective lens balancing and correcting all types of aberrations within the system; when the fifth lens element has positive refractive power, coma can be effectively corrected while preventing other aberrations from becoming too large; when the fifth lens element has negative refractive power, the principal point of the optical system can be further away from the image plane, favorably reducing the total track length of the system in order to maintain the compactness of the lens assembly.

In the present photographing optical lens assembly, the first lens element may be a bi-convex lens element or a meniscus lens element having a convex object-side surface and a concave image-side surface. When the first lens element is a bi-convex lens element, the refractive power thereof can be effectively enhanced, thus shortening the total track length of the photographing optical lens assembly. When the first lens element is a meniscus lens element, the astigmatism of the system can be corrected more favorably. The second lens element has a concave object-side surface and a concave image-side surface that effectively correct the Petzval Sum of the system, allowing the surrounding image plane to become more flat and to favorably extend the back focal length of the system, thereby providing sufficient space to accommodate other components. The third lens element may be a meniscus with a concave object-side surface and a convex image-side surface whereas the fourth and fifth lens elements are meniscus lens elements with a convex object-side surface and a concave image-side surface so as to correct the astigmatism and obtain high image quality in the system. Moreover, the third, fourth, and fifth lens elements are meniscus lens elements with more balanced refractive power that effectively reduces the system sensitivity.

In the aforementioned photographing optical lens assembly, the aperture stop can be disposed between the imaged object and the first lens element, the first lens element and the second lens element, or the second lens element and the third lens element. The first lens element provides positive refractive power, and the aperture stop is disposed near the object side of the photographing optical lens assembly, thereby the total track length of the photographing optical lens assembly can be reduced effectively. The aforementioned arrangement also enables the exit pupil of the photographing optical lens assembly to be positioned far away from the image plane, thus light will be projected onto the electronic sensor at a nearly perpendicular angle, and this is the telecentric feature of the image side. The telecentric feature is very important to the photosensitivity of the solid-state sensor as it can improve the photosensitivity of the sensor and reduce the probability of the shading occurrence. Moreover, the fifth lens element is provided with at least one inflection point, thereby the angle at which the light is projected onto the sensor from the off-axis field can be effectively reduced to further correct the off-axis aberrations. In addition, when the aperture stop is disposed closer to the third lens elements, a wide field of view can be favorably achieved. Such stop placement facilitates the correction of the distortion and chromatic aberration of magnification, and the mitigation of the system's sensitivity. Therefore, in the present photographing optical lens assembly, the aperture stop is placed between the imaged object and the third lens element for the purpose of achieving a balance between the telecentric feature and wide field of view of the photographing optical lens assembly; preferably, the aperture stop is disposed between the first lens element and the second lens element.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides a photographing optical lens assembly comprising, in order from the object side to the 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 concave object-side surface and a concave image-side surface; a third lens element with positive refractive power; a fourth lens element with negative refractive power having a convex object-side surface and a concave image-side surface, at least one of the object-side and image-side surfaces thereof being aspheric; and a fifth lens element having a convex object-side surface and a concave image-side surface, at least one inflection point formed on the image-side surface, made of plastic; wherein the photographing optical lens assembly further comprises an aperture stop and an electronic sensor for image formation; wherein the aperture stop is disposed between the imaged object and the third lens element; wherein the lens element of the photographing optical lens assembly with refractive power closest to the object side is the first lens element, and there are at most six lens elements with refractive power; and wherein the radius of curvature on the image-side surface of the second lens element is R4, the focal length of the photographing optical lens assembly is f, the Abbe number of the first lens element is V1, the Abbe number of the second lens element is V2, the distance on the optical axis between the aperture stop and the electronic sensor is SL, the distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, and they satisfy the relation:
0.3<R4/f<30.0;
23.0<V1-V2<45.0;
0.65<SL/TTL<1.10

When the aforementioned photographing optical lens assembly satisfies the relation: 0.3<R4/f<30.0, the back focal distance can be effectively increased to allow placement of other components; preferably, they satisfy the relation: 0.6<R4/f<2.0. When the aforementioned photographing optical lens assembly satisfies the relation: 23.0<V1-V2<45.0, the chromatic aberration of the photographing optical lens assembly can be favorably corrected; preferably, they satisfy the relation: 31.0<V1-V2<42.0. When the aforementioned photographing optical lens assembly satisfies the relation: 0.65<SL/TTL<1.10, the photographing optical lens assembly can obtain a good balance between the telecentric feature and wide field of view; preferably, the aperture stop is disposed between the first lens element and the second lens element, and they satisfy the relation: 0.78<SL/TTL<0.93.

In the aforementioned photographing optical lens assembly, it is preferable that the third lens element has a concave object-side surface and a convex image-side surface so as to favorably correct the astigmatism of the system; preferably, the fifth lens element has negative refractive power, causing the principal point of the optical system to be away from the image plane which reduces the total track length of the optical system to maintain the compact size of the lens assembly; preferably, there are five lens elements with refractive power in the photographing lens assembly, and with suitable number of lens elements, the system can obtain higher image quality without having the total track length of the lens assembly being too long.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 0.80<f/f1<2.00, wherein the focal length of the photographing optical lens assembly is f, the focal length of the first lens element is f1. When the above relation is satisfied, the refractive power of the first lens element is more balanced so that the total track length of the system can be effectively controlled to keep the photographing optical lens assembly compact while preventing the high order spherical aberration from becoming too large with improved image quality, preferably, they satisfy the relation: 1.32<f/f1<2.00.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 0.25<f1/f3<1.20, wherein the focal length of the first lens element is f1, the focal length of the third lens element is f3. When the photographing optical lens assembly satisfies the above relation, the distribution of refractive power from the first lens element and the third lens element is more balanced, which reduces the sensitivity of the system and the generation of aberration.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 0.3<(CT2/f)*10<1.1, wherein the thickness on the optical axis of the second lens element is CT2, the focal length of the photographing optical lens assembly is f. When the photographing optical lens assembly satisfies the above relation, the thickness of the second lens element is better suited for obtaining a good balance between the manufacturing yields and correcting the aberration of the system, and favorable for moldability and homogeneity of injection molding of plastic lenses.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 0.5<(T12/f)*100<9.5, wherein the distance on the optical axis between the first and second lens elements is T12, the focal length of the photographing lens assembly is f. When the photographing lens assembly satisfies the above relation, the distance on the optical axis between the first and second lens elements is better for avoiding difficulties in lens assembly due to tight spacing or the distance from being too long where the lens assembly will no longer be compact; preferably, they satisfy the relation: 0.5<(T12/f)*100<5.5.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: −0.35<f/f5<0.35, wherein the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element is f5. When the photographing optical lens assembly satisfies the above relation, the fifth lens element serves as a corrective lens element, which corrects the aberration and distortion of the system and increases the resolution of the photographing optical lens assembly.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: TTL/ImgH<1.95, wherein the distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH. When the photographing optical lens assembly satisfies the above relation, to the photographing optical lens assembly can maintain a compact form so that it can be installed in compact portable electronic products.

According to another aspect of the present invention, a photographing optical lens assembly comprises, in order from the object side to the 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 concave object-side surface and a concave image-side surface; a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface; a fourth lens element with negative refractive power at least one of the object-side and image-side surfaces thereof being aspheric; and a fifth lens element having a convex object-side surface and a concave image-side surface, the object-side and image-side surfaces thereof being aspheric; wherein the photographing optical lens assembly further comprises an aperture stop and an electronic sensor for image formation, the aperture stop is disposed between the imaged object and the third lens element; wherein there are five lens elements with refractive power; and wherein the radius of curvature on the image-side surface of the second lens element is R4, the focal length of the photographing optical lens assembly is f, the distance on the optical axis between the first lens element and the second lens element is T12, the distance on the optical axis between the aperture stop and the electronic sensor is SL, the distance on the optical axis between the object-side surface of the first lens element and the electronic sensor is TTL, and they satisfy the relation:
0.3<R4/f<30.0;
0.5<(T12/f)*100<15.0;
0.65<SL/TTL<1.10

When the aforementioned photographing optical lens assembly satisfies the relation: 0.3<R4/f<30.0, the back focal distance can be effectively increased to allow placement of other components; preferably, they satisfy the relation: 0.5<R4/f<10.0. When the aforementioned photographing optical lens assembly satisfies the relation: 0.5<(T12/f)*100<15.0, the distance on the optical axis between the first and second lens elements is more appropriate, avoiding difficulties in assembly due to tight spacing or too much spacing causing the lens assembly no longer being compact; moreover, they preferably satisfy the relation: 0.5<(T12/f)*100<9.5. When the aforementioned photographing optical lens assembly satisfies the relation: 0.65<SL/TTL<1.10, the photographing optical lens assembly can obtain a good balance between the telecentric feature and wide field of view; preferably, the aperture stop is disposed between the first lens element and the second lens element, and they satisfy the relation: 0.78<SL/TTL<0.93.

In the aforementioned photographing optical lens assembly, preferably, the fourth lens element has a convex object-side surface and a concave image-side surface for favorably correcting the aberration of the system; preferably, the fifth lens element has at least one inflection point on the image-side surface, thereby the angle at which the light is projected onto the sensor from the off-axis field can be effectively reduced to further correct the off-axis aberrations; preferably, the fifth lens element is made of plastic that the adoption of plastic material in lens manufacturing can effectively reduce the weight of the lens assembly while reducing production costs.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 31.0<V1-V2<42.0, wherein the Abbe number of the first lens element is V1, the Abbe number of the second lens element is V2. When the photographing optical lens assembly satisfies the above relation, the chromatic aberration in the photographing optical lens assembly can be favorably corrected.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 1.32<f/f1<2.00, wherein the focal length of the photographing optical lens assembly is f, the focal length of the first lens element is f1. When the photographing optical lens assembly satisfies the above relation, the distribution of refractive power of the first lens element is more balanced, effectively maintaining the total track length of the system, being compact, and preventing the high order spherical aberration from begin too large, in order to increase image quality.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: −0.35<f/f5<0.35, wherein the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element is f5. When the photographing optical lens assembly satisfies the above relation, the fifth lens element serves as a correcting lens which corrects the aberration and distortion of the system while increasing the resolution of the photographing optical lens assembly.

In the aforementioned photographing optical lens assembly, preferably, it satisfies the relation: 23.0<V3-V4<45.0, wherein the Abbe number of the third lens element is V3, the Abbe number of the fourth lens element is V4. When the photographing optical lens assembly satisfies the above relation, the chromatic aberration of the photographing optical lens assembly can be favorably corrected.

In the present photographing optical lens assembly, the lens elements can be made of glass or plastic. If the lens elements are made of glass, there is more freedom in distributing the refractive power of the system. If plastic material is adopted to produce the lens elements, the production cost will be reduced effectively. Additionally, the surfaces of the lens elements can be aspheric and easily made into non-spherical profiles, allowing more design parameter freedom which can be used to reduce aberrations and the number of the lens elements, so that the total track length of the photographing optical lens assembly can be effectively reduced.

In the present photographing optical lens assembly, if a lens element has a convex surface, it means the portion of the surface in proximity to the axis is convex; if a lens element has a concave surface, it means the portion of the surface in proximity to the axis is concave.

Preferred embodiments of the present invention will be described in the following paragraphs by referring to the accompanying drawings.

FIG. 1shows a photographing optical lens assembly in accordance with a first embodiment of the present invention, andFIG. 2shows the aberration curves of the first embodiment of the present invention. The photographing optical lens assembly of the first embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element110with positive refractive power having a convex object-side surface111and a convex image-side surface112, the object-side and image-side surfaces111and112thereof being aspheric; a plastic second lens element120with negative refractive power having a concave object-side surface121and a concave image-side surface122, the object-side and image-side surfaces121and122thereof being aspheric; a plastic third lens element130with positive refractive power having a concave object-side surface131and a convex image-side surface132, the object-side and image-side surfaces131and132thereof being aspheric; a plastic fourth lens element140with negative refractive power having a convex object-side surface141and a concave image-side surface142, the object-side surface141and the image-side surface142thereof being aspheric; a plastic fifth lens element150with positive refractive power having a convex object-side surface151and a concave image-side surface152, the object-side surface151and the image-side surface152thereof being aspheric, at least one inflection point is formed on the image-side surface152; wherein an aperture stop100is disposed between the imaged object and the first lens elements110; wherein an IR filter160is disposed between the image-side surface152of the fifth lens element150and an image plane170; and wherein the IR filter160has no influence on the focal length of the photographing optical lens assembly.

The equation of the aspheric surface profiles is expressed as follows:

X: the height of a point on the aspheric surface at a distance Y from the optical axis relative to the tangential plane at the aspheric surface vertex;

Y: the distance from the point on the curve of the aspheric surface to the optical axis;

Ai: the aspheric coefficient of order i.

In the first embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=3.90 (mm).

In the first embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.80.

In the first embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=36.0 deg.

In the first embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element110is V1, the Abbe number of the second lens element120is V2, and they satisfy the relation:
V1-V2=32.5.

In the first embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element130is V3, the Abbe number of the fourth lens element140is V4, and they satisfy the relation:
V3-V4=32.4.

In the first embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element120is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=1.42.

In the first embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface122of the second lens element120is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=5.79.

In the first embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element110is f1, and they satisfy the relation:
f/f1=1.14.

In the first embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element150is f5, and they satisfy the relation:
f/f5=0.05.

In the first embodiment of the present photographing optical lens assembly, the focal length of the first lens element110is f1, the focal length of the third lens element130is f3, and they satisfy the relation:
f1/f3=0.78.

In the first embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element110and the second lens element120is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=7.77.

In the first embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane170for image formation. The distance on the optical axis between the aperture stop100and the electronic sensor is SL, the distance on the optical axis between the object-side surface111of the first lens element110and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=1.02.

In the first embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface111of the first lens element110and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.80.

The detailed optical data of the first embodiment is shown inFIG. 13(TABLE 1), and the aspheric surface data is shown inFIGS. 14A and 14B

(TABLES 2A and 2B), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

FIG. 3shows a photographing optical lens assembly in accordance with a second embodiment of the present invention, andFIG. 4shows the aberration curves of the second embodiment of the present invention. The photographing optical lens assembly of the second embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element210with positive refractive power having a convex object-side surface211and a convex image-side surface212, the object-side and image-side surfaces211and212thereof being aspheric; a plastic second lens element220with negative refractive power having a concave object-side surface221and a concave image-side surface222, the object-side and image-side surfaces221and222thereof being aspheric; a plastic third lens element230with positive refractive power having a concave object-side surface231and a convex image-side surface232, the object-side and image-side surfaces231and232thereof being aspheric; a plastic fourth lens element240with negative refractive power having a convex object-side surface241and a concave image-side surface242, the object-side and image-side surfaces241and242thereof being aspheric; and a plastic fifth lens element250with negative refractive power having a convex object-side surface251and a concave image-side surface252, the object-side and image-side surfaces251and252thereof being aspheric, at least one inflection point formed on the image-side surface252; wherein an aperture stop200is disposed between the imaged object and the first lens element210; wherein an IR filter260is disposed between the image-side surface252of the fifth lens element250and an image plane270; and wherein the IR filter260has no influence on the focal length of the photographing optical lens assembly.

The equation of the aspheric surface profiles of the second embodiment has the same form as that of the first embodiment.

In the second embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=3.94 (mm).

In the second embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.80.

In the second embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=35.7 deg.

In the second embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element210is V1, the Abbe number of the second lens element220is V2, and they satisfy the relation:
V1-V2=32.5.

In the second embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element230is V3, the Abbe number of the fourth lens element240is V4, and they satisfy the relation:
V3-V4=32.4.

In the second embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element220is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=1.43.

In the second embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface222of the second lens element220is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=5.97.

In the second embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element210is f1, and they satisfy the relation:
f/f1=1.16.

In the second embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element250is f5, and they satisfy the relation:
f/f5=−0.16.

In the second embodiment of the present photographing optical lens assembly, the focal length of the first lens element210is f1, the focal length of the third lens element230is f3, and they satisfy the relation:
f1/f3=0.84.

In the second embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element210and the second lens element220is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=7.46.

In the second embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane270for image formation. The distance on the optical axis between the aperture stop200and the electronic sensor is SL, the distance on the optical axis between the object-side surface211of the first lens element210and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=1.02.

In the second embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface211of the first lens element210and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.80.

The detailed optical data of the second embodiment is shown inFIG. 15(TABLE 3), and the aspheric surface data is shown inFIGS. 16A and 16B(TABLES 4A and 4B), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

FIG. 5shows a photographing optical lens assembly in accordance with a third embodiment of the present invention, andFIG. 6shows the aberration curves of the third embodiment of the present invention. The photographing optical lens assembly of the third embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element310with positive refractive power having a convex object-side surface311and a convex image-side surface312, the object-side and image-side surfaces311and312thereof being aspheric; a plastic second lens element320with negative refractive power having a concave object-side surface321and a concave image-side surface322, the object-side and image-side surfaces321and322thereof being aspheric; a plastic third lens element330with positive refractive power having a concave object-side surface331and a convex image-side surface332, the object-side and image-side surfaces331and332thereof being aspheric; a plastic fourth lens element340with negative refractive power having a convex object-side surface341and a concave image-side surface342, the object-side and image-side surfaces341and342thereof being aspheric; and a plastic fifth lens element350with negative refractive power having a convex object-side surface351and a concave image-side surface352, the object-side and image-side surfaces351and352thereof being aspheric, at least one inflection point formed on the image-side surface352; wherein an aperture stop300is disposed between the first and second lens elements310and320; wherein an IR filter360is disposed between the image-side surface352of the fifth lens element350and an image plane370; and wherein the IR filter360has no influence on the focal length of the photographing optical lens assembly.

The equation of the aspheric surface profiles of the third embodiment has the same form as that of the first embodiment.

In the third embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=4.23 (mm).

In the third embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.78.

In the third embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=33.8 deg.

In the third embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element310is V1, the Abbe number of the second lens element320is V2, and they satisfy the relation:
V1-V2=32.5.

In the third embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element330is V3, the Abbe number of the fourth lens element340is V4, and they satisfy the relation:
V3-V4=23.8.

In the third embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element320is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=0.80.

In the third embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface322of the second lens element320is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=1.15.

In the third embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element310is f1, and they satisfy the relation:
f/f1=1.33.

In the third embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element350is f5, and they satisfy the relation:
f/f5=−0.06.

In the third embodiment of the present photographing optical lens assembly, the focal length of the first lens element310is f1, the focal length of the third lens element330is f3, and they satisfy the relation:
f1/f3=0.65.

In the third embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element310and the second lens element320is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=3.66.

In the third embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane370for image formation. The distance on the optical axis between the aperture stop300and the electronic sensor is SL, the distance on the optical axis between the object-side surface311of the first lens element310and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=0.90.

In the third embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface311of the first lens element310and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.82.

The detailed optical data of the third embodiment is shown inFIG. 17(TABLE 5), and the aspheric surface data is shown inFIGS. 18A and 18B(TABLES 6A and 6B), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

FIG. 7shows a photographing optical lens assembly in accordance with a fourth embodiment of the present invention, andFIG. 8shows the aberration curves of the fourth embodiment of the present invention. The photographing optical lens assembly of the fourth embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element410with positive refractive power having a convex object-side surface411and a convex image-side surface412, the object-side and image-side surfaces411and412thereof being aspheric; a plastic second lens element420with negative refractive power having a concave object-side surface421and a concave image-side surface422, the object-side and image-side surfaces421and422thereof being aspheric; a plastic third lens element430with positive refractive power having a concave object-side surface431and a convex image-side surface432, the object-side and image-side surfaces431and432thereof being aspheric; a plastic fourth lens element440with negative refractive power having a convex object-side surface441and a concave image-side surface442, the object-side and image-side surfaces441and442thereof being aspheric; and a plastic fifth lens element450with positive refractive power having a convex object-side surface451and a concave image-side surface452, the object-side and image-side surfaces451and452thereof being aspheric, at least one inflection point formed on the image-side surface452; wherein an aperture stop400is disposed between the imaged object and the first lens element410; wherein an IR filter460is disposed between the image-side surface452of the fifth lens element450and an image plane470; and wherein the IR filter460has no influence on the focal length of the photographing optical lens assembly. The equation of the aspheric surface profiles of the fourth embodiment has the same form as that of the first embodiment.

In the fourth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=4.06 (mm).

In the fourth embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.80.

In the fourth embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=35.0 deg.

In the fourth embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element410is V1, the Abbe number of the second lens element420is V2, and they satisfy the relation:
V1-V2=32.5.

In the fourth embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element430is V3, the Abbe number of the fourth lens element440is V4, and they satisfy the relation:
V3-V4=−0.1.

In the fourth embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element420is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=0.74.

In the fourth embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface422of the second lens element420is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=0.97.

In the fourth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element410is f1, and they satisfy the relation:
f/f1=1.64.

In the fourth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element450is f5, and they satisfy the relation:
f/f5=0.21.

In the fourth embodiment of the present photographing optical lens assembly, the focal length of the first lens element410is f1, the focal length of the third lens element430is f3, and they satisfy the relation:
f1/f3=0.62.

In the fourth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element410and the second lens element420is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=1.95.

In the fourth embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane470for image formation. The distance on the optical axis between the aperture stop400and the electronic sensor is SL, the distance on the optical axis between the object-side surface411of the first lens element410and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=0.99.

In the fourth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface411of the first lens element410and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.72.

The detailed optical data of the fourth embodiment is shown inFIG. 19(TABLE 7), and the aspheric surface data is shown inFIG. 20(TABLE 8), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

FIG. 9shows a photographing optical lens assembly in accordance with a fifth embodiment of the present invention, andFIG. 10shows the aberration curves of the fifth embodiment of the present invention. The photographing optical lens assembly of the fifth embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element510with positive refractive power having a convex object-side surface511and a convex image-side surface512, the object-side and image-side surfaces511and512thereof being aspheric; a plastic second lens element520with negative refractive power having a concave object-side surface521and a concave image-side surface522, the object-side and image-side surfaces521and522thereof being aspheric; a plastic third lens element530with positive refractive power having a concave object-side surface531and a convex image-side surface532, the object-side and image-side surfaces531and532thereof being aspheric; a plastic fourth lens element540with negative refractive power having a convex object-side surface541and a concave image-side surface542, the object-side and image-side surfaces541and542thereof being aspheric; and a plastic fifth lens element550with negative refractive power having a convex object-side surface551and a concave image-side surface552, the object-side and image-side surfaces551and552thereof being aspheric, at least one inflection point formed on the image-side surface552; wherein an aperture stop500is disposed between the imaged object and the first lens elements510; wherein an IR filter560is disposed between the image-side surface552of the fifth lens element550and an image plane570; and wherein the IR filter560has no influence on the focal length of the photographing optical lens assembly.

The equation of the aspheric surface profiles of the fifth embodiment has the same form as that of the first embodiment.

In the fifth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=4.06 (mm).

In the fifth embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.80.

In the fifth embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=35.0 deg.

In the fifth embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element510is V1, the Abbe number of the second lens element520is V2, and they satisfy the relation:
V1-V2=32.5.

In the fifth embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element530is V3, the Abbe number of the fourth lens element540is V4, and they satisfy the relation:
V3-V4=−0.1.

In the fifth embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element520is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=0.74.

In the fifth embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface522of the second lens element520is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=0.94.

In the fifth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element510is f1, and they satisfy the relation:
f/f1=1.75.

In the fifth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element550is f5, and they satisfy the relation:
f/f5=−0.52.

In the fifth embodiment of the present photographing optical lens assembly, the focal length of the first lens element510is f1, the focal length of the third lens element530is f3, and they satisfy the relation:
f1/f3=0.32.

In the fifth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element510and the second lens element520is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=1.23.

In the fifth embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane570for image formation. The distance on the optical axis between the aperture stop500and the electronic sensor is SL, the distance on the optical axis between the object-side surface511of the first lens element510and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=0.97.

In the fifth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface511of the first lens element510and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.58.

The detailed optical data of the fifth embodiment is shown inFIG. 21(TABLE 9), and the aspheric surface data is shown inFIG. 22(TABLE 10), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

FIG. 11shows a photographing optical lens assembly in accordance with a sixth embodiment of the present invention, andFIG. 12shows the aberration curves of the sixth embodiment of the present invention. The photographing optical lens assembly of the sixth embodiment of the present invention mainly comprises five lens elements, in order from the object side to the image side: a plastic first lens element610with positive refractive power having a convex object-side surface611and a concave image-side surface612, the object-side and image-side surfaces611and612thereof being aspheric; a plastic second lens element620with negative refractive power having a concave object-side surface621and a concave image-side surface622, the object-side and image-side surfaces621and622thereof being aspheric; a plastic third lens element630with positive refractive power having a concave object-side surface631and a convex image-side surface632, the object-side and image-side surfaces631and632thereof being aspheric; a plastic fourth lens element640with negative refractive power having a convex object-side surface641and a concave image-side surface642, the object-side and image-side surfaces641and642thereof being aspheric; and a plastic fifth lens element650with positive refractive power having a convex object-side surface651and a concave image-side surface652, the object-side and image-side surfaces651and652thereof being aspheric, at least one inflection point formed on the image-side surface652; wherein an aperture stop600is disposed between the first lens element610and second lens elements620; wherein an IR filter660is disposed between the image-side surface652of the fifth lens element650and an image plane670; and wherein the IR filter660has no influence on the focal length of the photographing optical lens assembly.

The equation of the aspheric surface profiles of the sixth embodiment has the same form as that of the first embodiment.

In the sixth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, and it satisfies the relation: f=4.22 (mm).

In the sixth embodiment of the present photographing optical lens assembly, the f-number of the photographing optical lens assembly is Fno, and it satisfies the relation: Fno=2.78.

In the sixth embodiment of the present photographing optical lens assembly, half of the maximal field of view of the photographing optical lens assembly is HFOV, and it satisfies the relation: HFOV=33.7 deg.

In the sixth embodiment of the present photographing optical lens assembly, the Abbe number of the first lens element610is V1, the Abbe number of the second lens element620is V2, and they satisfy the relation:
V1-V2=32.5.

In the sixth embodiment of the present photographing optical lens assembly, the Abbe number of the third lens element630is V3, the Abbe number of the fourth lens element640is V4, and they satisfy the relation:
V3-V4=−0.1.

In the sixth embodiment of the present photographing optical lens assembly, the thickness on the optical axis of the second lens element620is CT2, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(CT2/f)*10=0.71.

In the sixth embodiment of the present photographing optical lens assembly, the radius of curvature of the image-side surface622of the second lens element620is R4, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
R4/f=1.05.

In the sixth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the first lens element610is f1, and they satisfy the relation:
f/f1=1.19.

In the sixth embodiment of the present photographing optical lens assembly, the focal length of the photographing optical lens assembly is f, the focal length of the fifth lens element650is f5, and they satisfy the relation:
f/f5=0.12.

In the sixth embodiment of the present photographing optical lens assembly, the focal length of the first lens element610is f1, the focal length of the third lens element630is f3, and they satisfy the relation:
f1/f3=1.08.

In the sixth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the first lens element610and the second lens element620is T12, the focal length of the photographing optical lens assembly is f, and they satisfy the relation:
(T12/f)*100=5.47.

In the sixth embodiment of the present photographing optical lens assembly, an electronic sensor is disposed at the image plane670for image formation. The distance on the optical axis between the aperture stop600and the electronic sensor is SL, the distance on the optical axis between the object-side surface611of the first lens element610and the electronic sensor is TTL, and they satisfy the relation:
SL/TTL=0.86.

In the sixth embodiment of the present photographing optical lens assembly, the distance on the optical axis between the object-side surface611of the first lens element610and the electronic sensor is TTL, half of the diagonal length of the effective pixel area of the electronic sensor is ImgH, and they satisfy the relation:
TTL/ImgH=1.86.

The detailed optical data of the sixth embodiment is shown inFIG. 23(TABLE 11), and the aspheric surface data is shown inFIG. 24(TABLE 12), wherein the units of the radius of curvature, the thickness and the focal length are expressed in mm, and HFOV is half of the maximal field of view.

It is to be noted that TABLES 1-12 (illustrated inFIGS. 13-24respectively) show different data of the different embodiments, however, the data of the different embodiments are obtained from experiments. Therefore, any photographing optical lens assembly of the same structure is considered to be within the scope of the present invention even if it uses different data. The embodiments depicted above and the appended drawings are exemplary and are not intended to limit the claim scope of the present invention. TABLE 13 (illustrated inFIG. 25) shows the data of the respective embodiments resulting from the equations.