Optical lens system

An optical lens system includes an aperture stop and an optical assembly, the optical assembly includes, in order from an object side to an image side: a first lens element with a positive refractive power; a second lens element with a negative refractive power; a third lens element with a positive refractive power; a fourth lens element with a positive refractive power; a fifth lens element with a negative refractive power; the aperture stop is located between an image-side surface of the first lens element and an object to be photographed. The optical lens system satisfies the following conditions: 0.55<TD/CA52<0.73; 20<Vd3−Vd2<40; 80<FOV<100; and 1.0<TL/ImgH<1.6.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical lens system, and more particularly to a miniaturized five-piece optical lens system applicable to electronic products.

2. Description of the Prior Art

Small imaging lens system with high image quality has become the standard equipment for portable electronic products, and with the development of social networks, more and more people like to take photographs or take selfies and share with others, therefore, there's an increasing demand for angle of view. The optical lens systems disclosed in U.S. Pat. Nos. 8,335,043 and 8,576,497 are all provided with five to six lens elements in order to provide wider angle of view, which, however, causes large distortion and long total track length. The optical lens systems disclosed in U.S. Pat. Nos. 8,248,713 and 7,446,955 are capable of wide-angle shooting by using a first lens element with a negative refractive power and three to four lens elements with refracting power, however, the total track length of these lens systems is also too long. The optical lens systems disclosed in U.S. Pat. Nos. 20130235463 and 8,390,941 are provided with more than two pieces of high-index lens elements, and the lens refractive power of the second or third lens element is small, which will increase the cost and make other lens elements burden with too much refractive power, thus increasing the sensitivity to assembly tolerance.

The present invention been made in order to solve the above-mentioned problems.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide an optical lens system having a wide field of view, high resolution, extra short track length, low material cost and low sensitivity to assembly tolerance.

According to one aspect of the present invention, an optical lens system comprises an aperture stop and an optical assembly, the optical assembly comprises, in order from the object side to the image side: a first lens element with a positive refractive power having an object-side surface being convex near the optical axis, the first lens element being made of plastic material, at least one of the object-side and an image-side surfaces of the first lens element being aspheric; a second lens element with a negative refractive power having an image-side surface being concave near the optical axis, the second lens element being made of plastic material; a third lens element with a positive refractive power having an aspheric object-side surface and an aspheric image-side surface, the third lens element being made of plastic material; a fourth lens element with a positive refractive power having an object-side surface being concave near the optical axis and an image-side surface being convex near the optical axis; a fifth lens element with a negative refractive power having an aspheric object-side surface being convex near the optical axis and an aspheric image-side surface being concave near the optical axis, the fifth lens element being made of plastic material, more than one inflection point being formed on the object-side surface and the image-side surface of the fifth lens element; and the aperture stop being located between the image-side surface of the first lens element and an object to be photographed; wherein the distance along an optical axis from the object-side surface of the first lens element to the image-side surface of the fifth lens element is TD, the maximum effective diameter of the image-side surface of the fifth lens element is CA52, the Abbe number of the second lens element is Vd2, the Abbe number of the third lens element is Vd3, the maximal field of view of the optical lens system is FOV, the distance from the object-side surface of the first lens element to the image plane along the optical axis is TL, the half of the maximum diagonal imaging height of the optical lens system is ImgH, and the following conditions are satisfied:

If TD/CA52 satisfies the above relation, it can further maintain the objective of miniaturization of the optical lens system.

If Vd3−Vd2 satisfies the above relation, the chromatic aberration of the optical lens system can be well corrected.

If FOV satisfies the above condition, the larger field of view can be provided for wide-range imaging.

If TL/ImgH satisfies the above condition, it can further maintain the objective of miniaturization of the optical lens system.

Preferably, the focal length of the second lens element is f2, the focal length of the third lens element is f3, and the following condition is satisfied: −5<f2/f3<−0.65, which will be favorable to correct the aberrations of the optical lens system.

Preferably, the radius of curvature of the object-side surface of the fourth lens element is R7, the radius of curvature of the image-side surface of the fourth lens element is R8, and the following condition is satisfied: 1.1<R7/R8<4.2, which will be favorable to distribute the positive refractive power of the fourth lens element, so as to reduce the sensitivity of the optical lens system to assembly tolerance and make the optical lens system easy to manufacture.

Preferably, the radius of curvature of the image-side surface of the second lens element is R4, the radius of curvature of the object-side surface of the third lens element is R5, and the following condition is satisfied: −0.3<R4/R5<7, which can reduce the refractive angle of rays with respect to the second lens element and the incident angle of rays with respect to the third lens element, so as to reduce the assembly sensitivity of the optical lens system.

Preferably, the focal length of the third lens element is f3, the focal length of the fourth lens element is f4, and the following condition is satisfied: 0.5<f3/f4<4.7, so that the refractive power of the third lens element and the fourth lens element are more balanced, it will be favorable to reduce the sensitivity of the system and correct the high order aberrations of the system.

Preferably, the distance along an optical axis between the third lens element and the fourth lens element is T34, the distance along an optical axis between the first lens element and the second lens element is T12, and the following condition is satisfied: 0.8<T34/T12<3, which can reduce the total track length of the optical lens system.

Preferably, the distance along an optical axis between the third lens element and the fourth lens element is T34, the distance along an optical axis between the second lens element and the third lens element is T23, the distance along an optical axis between the fourth lens element and the fifth lens element is T45, and the following condition is satisfied: 0.1<T34−(T23+T45)<1, which can further reduce the total track length of the optical lens system, so as to maintain the objective of miniaturization of the optical lens system.

Preferably, the Abbe number of the fourth lens element is Vd4, the Abbe number of the fifth lens element is Vd5, and the following condition is satisfied: 0≦|Vd4−Vd5|<10, which can further correct the chromatic aberration caused by the optical lens system.

Preferably, the focal length of the optical lens system is f, the focal length of the first lens element is f1, and the following condition is satisfied: 1.1<f1/f<3.5, the distribution of the refractive power of the first lens can be controlled, so that the optical lens system can maintain a wider angle of view, and the sensitivity of the optical lens system assembly can be reduced.

According to another aspect of the present invention, an optical lens system comprises an aperture stop and an optical assembly, the optical assembly comprises, in order from the object side to the image side: a first lens element with a positive refractive power having an object-side surface being convex near the optical axis; a second lens element with a negative refractive power having an image-side surface being concave near the optical axis, the second lens element being made of plastic material; a third lens element with a refractive power having an aspheric object-side surface and an aspheric image-side surface, the third lens element being made of plastic material; a fourth lens element with a positive refractive power having an object-side surface being concave near the optical axis and an image-side surface being convex near the optical axis; a fifth lens element with a negative refractive power having an aspheric object-side surface being convex near the optical axis and an aspheric image-side surface being concave near the optical axis, more than one inflection point being formed on the object-side surface and the image-side surface of the fifth lens element; and the aperture stop being located between the image-side surface of the first lens element and an object to be photographed; wherein the focal length of the optical lens system is f, the entrance pupil diameter of the optical lens system is EPD, the maximal field of view of the optical lens system is FOV, the distance from the object-side surface of the first lens element to the image plane along the optical axis is TL, the half of the maximum diagonal imaging height of the optical lens system is ImgH, and the following conditions are satisfied:

If f/EPD satisfies the above condition, a better image quality can also be obtained even in a dark shooting environment.

If FOV satisfies the above condition, the larger field of view can be provided for wide-range imaging.

If TL/ImgH satisfies the above condition, it can further maintain the objective of miniaturization of the optical lens system.

Preferably, the first lens element is made of plastic, and the third lens element has a positive refractive power. Plastic material will be favorable to manufacture the aspheric lens element, and the cost will be effectively reduced. The third lens element with a positive refractive power can correct the field curvature of the optical lens system.

Preferably, the focal length of the second lens element is f2, the focal length of the third lens element is f3, and the following condition is satisfied: −5<f2/f3<−0.65, which will be favorable to correct the aberrations of the optical lens system.

Preferably, the distance along an optical axis between the third lens element and the fourth lens element is T34, the distance along an optical axis between the second lens element and the third lens element is T23, the distance along an optical axis between the fourth lens element and the fifth lens element is T45, and the following condition is satisfied: 0.1<T34−(T23+T45)<1, which can further reduce the total track length of the optical lens system, so as to maintain the objective of miniaturization of the optical lens system.

Preferably, the radius of curvature of the image-side surface of the second lens element is R4, the radius of curvature of the object-side surface of the third lens element is R5, and the following condition is satisfied: 0.3<R4/R5<7, which can reduce the refractive angle of rays with respect to the second lens element and the incident angle of rays with respect to the third lens element, so as to reduce the assembly sensitivity of the optical lens system.

Preferably, the focal length of the third lens element is f3, the focal length of the fourth lens element is f4, and the following condition is satisfied: 0.5<f3/f4<4.7, so that the refractive power of the third lens element and the fourth lens element are more balanced, it will be favorable to reduce the sensitivity of the system and correct the high order aberrations of the system.

Preferably, the focal length of the optical lens system is f, the focal length of the first lens element is f1, and the following condition is satisfied: 1.1<f1/f<3.5, the distribution of the refractive power of the first lens can be controlled, so that the optical lens system can maintain a wider angle of view, and the sensitivity of the optical lens system assembly can be reduced.

According to another aspect of the present invention, an optical lens system comprises an aperture stop and an optical assembly, the optical assembly comprises, in order from the object side to the image side: a first lens element with a positive refractive power having an object-side surface being convex near the optical axis; a second lens element with a negative refractive power having an image-side surface being concave near the optical axis, the second lens element being made of plastic material; a third lens element with a positive refractive power, the third lens element being made of plastic material; a fourth lens element with a positive refractive power having an object-side surface being concave near the optical axis and an image-side surface being convex near the optical axis; a fifth lens element with a negative refractive power having an aspheric object-side surface being convex near the optical axis and an aspheric image-side surface being concave near the optical axis, more than one inflection point being formed on the object-side surface and the image-side surface of the fifth lens element; and the aperture stop being located between the image-side surface of the first lens element and an object to be photographed; wherein the distance along an optical axis from the object-side surface of the first lens element to the image-side surface of the fifth lens element is TD, the maximum effective diameter of the image-side surface of the fifth lens element is CA52, the focal length of the optical lens system is f, the focal length of the first lens element is f1, the maximal field of view of the optical lens system is FOV, the Abbe number of the second lens element is Vd2, the Abbe number of the third lens element is Vd3, the Abbe number of the fourth lens element is Vd4, the Abbe number of the fifth lens element is Vd5, and the following conditions are satisfied:

If TD/CA52 satisfies the above relation, it can further maintain the objective of miniaturization of the optical lens system.

If f1/f satisfies the above relation, the distribution of the refractive power of the first lens can be controlled, so that the optical lens system can maintain a wider angle of view, and the sensitivity of the optical lens system assembly can be reduced.

If FOV satisfies the above condition, the larger field of view can be provided for wide-range imaging.

If Vd3−Vd2 and |Vd4−Vd5| satisfy the above conditions, the chromatic aberration of the optical lens system can be corrected.

Preferably, the focal length of the third lens element is f3, the focal length of the fourth lens element is f4, and the following condition is satisfied: 0.5<f3/f4<4.7, so that the refractive power of the third lens element and the fourth lens element are more balanced, it will be favorable to reduce the sensitivity of the system and correct the high order aberrations of the system.

Preferably, the distance along an optical axis between the third lens element and the fourth lens element is T34, the distance along an optical axis between the first lens element and the second lens element is T12, and the following condition is satisfied: 0.8<T34/T12<3, which can reduce the total track length of the optical lens system.

Preferably, the radius of curvature of the object-side surface of the fourth lens element is R7, the radius of curvature of the image-side surface of the fourth lens element is R8, and the following condition is satisfied: 1.1<R7/R8<4.2, which will be favorable to distribute the positive refractive power of the fourth lens element, so as to reduce the sensitivity of the optical lens system to assembly tolerance and make the optical lens system easy to manufacture.

Preferably, the focal length of the second lens element is f2, the focal length of the third lens element is f3, and the following condition is satisfied: −5<f2/f3<−0.65, which will be favorable to correct the aberrations of the optical lens system.

The present invention will be presented in further details from the following descriptions with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiments in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1Ashows an optical lens system in accordance with a first embodiment of the present invention, andFIG. 1Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the first embodiment of the present invention. An optical lens system in accordance with the first embodiment of the present invention comprises an aperture stop100and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element110, a second lens element120, a third lens element130, a fourth lens element140, a fifth lens element150, an IR cut filter160and an image plane170, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop100is located between an image-side surface112of the first lens element110and an object to be photographed.

The first lens element110with a positive refractive power has an object-side surface111being convex near an optical axis and the image-side surface112being concave near the optical axis, both the object-side and image-side surfaces111,112are aspheric, and the first lens element110is made of plastic material.

The second lens element120with a negative refractive power has an object-side surface121being convex near the optical axis and an image-side surface122being concave near the optical axis, both the object-side and image-side surfaces111,122are aspheric, and the second lens element120is made of plastic material.

The third lens element130with a positive refractive power has an object-side surface131being convex near the optical axis and an image-side surface132being convex near the optical axis, both the object-side and image-side surfaces131,132are aspheric, and the third lens element130is made of plastic material.

The fourth lens element140with a positive refractive power has an object-side surface141being concave near the optical axis and an image-side surface142being convex near the optical axis, both the object-side and image-side surfaces141,142are aspheric, and the fourth lens element140is made of plastic material.

The fifth lens element150with a negative refractive power has an object-side surface151being convex near the optical axis and an image-side surface152being concave near the optical axis, both the object-side and image-side surfaces151,152are aspheric, and the fifth lens element150is made of plastic material.

The IR cut filter160made of glass is located between the fifth lens element150and the image plane170and has no influence on the focal length of the optical lens system.

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

z represents the distance of a point on the aspheric surface at a height h from an optical axis190relative to a plane perpendicular to the optical axis at the vertex of the aspheric surface;

c is a paraxial curvature equal to 1/R (R: a paraxial radius of curvature);

h represents a vertical distance from the point on the curve of the aspheric surface to the optical axis;

k represents the conic constant;

In the first embodiment of the present optical lens system, the focal length of the optical lens system is f, the f-number of the optical lens system is Fno, half of the maximal field of view of the optical lens system is HFOV, and the following conditions are satisfied:

In the first embodiment of the present optical lens system, the focal length of the optical lens system is f, the entrance pupil diameter of the optical lens system is EPD, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the maximal field of view of the optical lens system is FOV, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the distance along the optical axis190from the object-side surface111of the first lens element110to the image-side surface152of the fifth lens element150is TD, the maximum effective diameter of the image-side surface152of the fifth lens element is CA52, and they satisfies the condition:

In the first embodiment of the present optical lens system, the distance from the object-side surface111of the first lens element110to the image plane170along the optical axis190is TL, the half of the maximum diagonal imaging height of the optical lens system is ImgH, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the focal length of the second lens element120is f2, the focal length of the third lens element130is f3, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the radius of curvature of the object-side surface141of the fourth lens element140is R7, the radius of curvature of the image-side surface142of the fourth lens element140is R8, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the radius of curvature of the image-side surface122of the second lens element120is R4, the radius of curvature of the object-side surface131of the third lens element130is R5, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the focal length of the third lens element130is f3, the focal length of the fourth lens element140is f4, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the distance along the optical axis190between the third lens element130and the fourth lens element140is T34, the distance along the optical axis190between the first lens element110and the second lens element120is T12, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the distance along the optical axis190between the third lens element130and the fourth lens element140is T34, the distance along the optical axis190between the second lens element120and the third lens element130is T23, the distance along the optical axis190between the fourth lens element140and the fifth lens element150is T45, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the Abbe number of the fourth lens element140is Vd4, the Abbe number of the fifth lens element150is Vd5, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the focal length of the optical lens system is f, the focal length of the first lens element110is f1, and the following condition is satisfied:

In the first embodiment of the present optical lens system, the Abbe number of the second lens element120is Vd2, the Abbe number of the third lens element130is Vd3, and the following condition is satisfied:

The detailed optical data of the first embodiment is shown in Table 1, and the aspheric surface data is shown in Table 2.

The units of the radius of curvature, the thickness and the focal length in table 1 are expressed in mm, in the tables 1 and 2, the surface numbers 2-11 represent the surfaces sequentially arranged from the object-side to the image-side along the optical axis, and in table 2, k represents the conic coefficient of the equation of the aspheric surface profiles, and A4, A6, A8, A10, A12, A14, A16. . . : represent the high-order aspheric coefficients arranging from the 4th order to the 16th order. The tables presented below for each embodiment are the corresponding schematic parameter and aberration curves, and the definitions of the tables are the same as Table 1 and Table 2 of the first embodiment. Therefore, an explanation in this regard will not be provided again.

Referring toFIG. 2Ashows an optical lens system in accordance with a second embodiment of the present invention, andFIG. 2Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the second embodiment of the present invention. An optical lens system in accordance with the second embodiment of the present invention comprises an aperture stop200and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element210, a second lens element220, a third lens element230, a fourth lens element240, a fifth lens element250, an IR cut filter260and an image plane270, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop200is located between an image-side surface212of the first lens element210and an object to be photographed.

The first lens element210with a positive refractive power has an object-side surface211being convex near the optical axis and the image-side surface212being convex near the optical axis, both the object-side and image-side surfaces211,212are aspheric, and the first lens element210is made of plastic material.

The second lens element220with a negative refractive power has an object-side surface221being convex near the optical axis and an image-side surface222being concave near the optical axis, both the object-side and image-side surfaces221,222are aspheric, and the second lens element220is made of plastic material.

The third lens element230with a positive refractive power has an object-side surface231being convex near the optical axis and an image-side surface232being convex near the optical axis, both the object-side and image-side surfaces231,232are aspheric, and the third lens element230is made of plastic material.

The fourth lens element240with a positive refractive power has an object-side surface241being concave near the optical axis and an image-side surface242being convex near the optical axis, both the object-side and image-side surfaces241,242are aspheric, and the fourth lens element240is made of plastic material.

The fifth lens element250with a negative refractive power has an object-side surface251being convex near the optical axis and an image-side surface252being concave near the optical axis, both the object-side and image-side surfaces251,252are aspheric, and the fifth lens element250is made of plastic material.

The IR cut filter260made of glass is located between the fifth lens element250and the image plane270and has no influence on the focal length of the optical lens system.

The detailed optical data of the second embodiment is shown in Table 3 and the aspheric surface data is shown in Table 4 below.

FIG. 3Ashows an optical lens system in accordance with a third embodiment of the present invention, andFIG. 3Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the third embodiment of the present invention. An optical lens system in accordance with the third embodiment of the present invention comprises an aperture stop300and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element310, a second lens element320, a third lens element330, a fourth lens element340, a fifth lens element350, an IR cut filter360and an image plane370, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop300is located between an image-side surface312of the first lens element310and an object to be photographed.

The first lens element310with a positive refractive power has an object-side surface311being convex near the optical axis and the image-side surface312being convex near the optical axis, both the object-side and image-side surfaces311,312are aspheric, and the first lens element310is made of plastic material.

The second lens element320with a negative refractive power has an object-side surface321being convex near the optical axis and an image-side surface322being concave near the optical axis, both the object-side and image-side surfaces321,322are aspheric, and the second lens element320is made of plastic material.

The third lens element330with a positive refractive power has an object-side surface331being convex near the optical axis and an image-side surface332being convex near the optical axis, both the object-side and image-side surfaces331,332are aspheric, and the third lens element330is made of plastic material.

The fourth lens element340with a positive refractive power has an object-side surface341being concave near the optical axis and an image-side surface342being convex near the optical axis, both the object-side and image-side surfaces341,342are aspheric, and the fourth lens element340is made of plastic material.

The fifth lens element350with a negative refractive power has an object-side surface351being convex near the optical axis and an image-side surface352being concave near the optical axis, both the object-side and image-side surfaces351,352are aspheric, and the fifth lens element350is made of plastic material.

The IR cut filter360made of glass is located between the fifth lens element350and the image plane370and has no influence on the focal length of the optical lens system.

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

FIG. 4Ashows an optical lens system in accordance with a fourth embodiment of the present invention, andFIG. 4Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the fourth embodiment of the present invention. An optical lens system in accordance with the fourth embodiment of the present invention comprises an aperture stop400and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element410, a second lens element420, a third lens element430, a fourth lens element440, a fifth lens element450, an IR cut filter460and an image plane470, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop400is located between an image-side surface412of the first lens element410and an object to be photographed.

The first lens element410with a positive refractive power has an object-side surface411being convex near the optical axis and the image-side surface412being concave near the optical axis, both the object-side and image-side surfaces411,412are aspheric, and the first lens element410is made of plastic material.

The second lens element420with a negative refractive power has an object-side surface421being concave near the optical axis and an image-side surface422being concave near the optical axis, both the object-side and image-side surfaces421,422are aspheric, and the second lens element420is made of plastic material.

The third lens element430with a positive refractive power has an object-side surface431being convex near the optical axis and an image-side surface432being convex near the optical axis, both the object-side and image-side surfaces431,432are aspheric, and the third lens element430is made of plastic material.

The fourth lens element440with a positive refractive power has an object-side surface441being concave near the optical axis and an image-side surface442being convex near the optical axis, both the object-side and image-side surfaces441,442are aspheric, and the fourth lens element440is made of plastic material.

The fifth lens element450with a negative refractive power has an object-side surface451being convex near the optical axis and an image-side surface452being concave near the optical axis, both the object-side and image-side surfaces451,452are aspheric, and the fifth lens element450is made of plastic material.

The IR cut filter460made of glass is located between the fifth lens element450and the image plane470and has no influence on the focal length of the optical lens system.

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

FIG. 5Ashows an optical lens system in accordance with a fifth embodiment of the present invention, andFIG. 5Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the fifth embodiment of the present invention. An optical lens system in accordance with the fifth embodiment of the present invention comprises an aperture stop500and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element510, a second lens element520, a third lens element530, a fourth lens element540, a fifth lens element550, an IR cut filter560and an image plane570, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop500is located between an image-side surface512of the first lens element510and an object to be photographed.

The first lens element510with a positive refractive power has an object-side surface511being convex near the optical axis and the image-side surface512being concave near the optical axis, both the object-side and image-side surfaces511,512are aspheric, and the first lens element510is made of plastic material.

The second lens element520with a negative refractive power has an object-side surface521being convex near the optical axis and an image-side surface522being concave near the optical axis, both the object-side and image-side surfaces521,522are aspheric, and the second lens element520is made of plastic material.

The third lens element530with a positive refractive power has an object-side surface531being convex near the optical axis and an image-side surface532being convex near the optical axis, both the object-side and image-side surfaces531,532are aspheric, and the third lens element530is made of plastic material.

The fourth lens element540with a positive refractive power has an object-side surface541being concave near the optical axis and an image-side surface542being convex near the optical axis, both the object-side and image-side surfaces541,542are aspheric, and the fourth lens element540is made of plastic material.

The fifth lens element550with a negative refractive power has an object-side surface551being convex near the optical axis and an image-side surface552being concave near the optical axis, both the object-side and image-side surfaces551,552are aspheric, and the fifth lens element550is made of plastic material.

The IR cut filter560made of glass is located between the fifth lens element550and the image plane570and has no influence on the focal length of the optical lens system.

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

FIG. 6Ashows an optical lens system in accordance with a sixth embodiment of the present invention, andFIG. 6Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the sixth embodiment of the present invention. An optical lens system in accordance with the sixth embodiment of the present invention comprises an aperture stop600and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element610, a second lens element620, a third lens element630, a fourth lens element640, a fifth lens element650, an IR cut filter660and an image plane670, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop600is located between an image-side surface612of the first lens element610and an object to be photographed.

The first lens element610with a positive refractive power has an object-side surface611being convex near the optical axis and the image-side surface612being concave near the optical axis, both the object-side and image-side surfaces611,612are aspheric, and the first lens element610is made of plastic material.

The second lens element620with a negative refractive power has an object-side surface621being convex near the optical axis and an image-side surface622being concave near the optical axis, both the object-side and image-side surfaces621,622are aspheric, and the second lens element620is made of plastic material.

The third lens element630with a positive refractive power has an object-side surface631being convex near the optical axis and an image-side surface632being concave near the optical axis, both the object-side and image-side surfaces631,632are aspheric, and the third lens element630is made of plastic material.

The fourth lens element640with a positive refractive power has an object-side surface641being concave near the optical axis and an image-side surface642being convex near the optical axis, both the object-side and image-side surfaces641,642are aspheric, and the fourth lens element640is made of plastic material.

The fifth lens element650with a negative refractive power has an object-side surface651being convex near the optical axis and an image-side surface652being concave near the optical axis, both the object-side and image-side surfaces651,652are aspheric, and the fifth lens element650is made of plastic material.

The IR cut filter660made of glass is located between the fifth lens element650and the image plane670and has no influence on the focal length of the optical lens system.

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

FIG. 7Ashows an optical lens system in accordance with a seventh embodiment of the present invention, andFIG. 7Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the seventh embodiment of the present invention. An optical lens system in accordance with the seventh embodiment of the present invention comprises an aperture stop700and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element710, a second lens element720, a third lens element730, a fourth lens element740, a fifth lens element750, an IR cut filter760and an image plane770, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop700is located between an image-side surface712of the first lens element710and an object to be photographed.

The first lens element710with a positive refractive power has an object-side surface711being convex near the optical axis and the image-side surface712being concave near the optical axis, both the object-side and image-side surfaces711,712are aspheric, and the first lens element710is made of plastic material.

The second lens element720with a negative refractive power has an object-side surface721being convex near the optical axis and an image-side surface722being concave near the optical axis, both the object-side and image-side surfaces721,722are aspheric, and the second lens element720is made of plastic material.

The third lens element730with a positive refractive power has an object-side surface731being convex near the optical axis and an image-side surface732being concave near the optical axis, both the object-side and image-side surfaces731,732are aspheric, and the third lens element730is made of plastic material.

The fourth lens element740with a positive refractive power has an object-side surface741being concave near the optical axis and an image-side surface742being convex near the optical axis, both the object-side and image-side surfaces741,742are aspheric, and the fourth lens element740is made of plastic material.

The fifth lens element750with a negative refractive power has an object-side surface751being convex near the optical axis and an image-side surface752being concave near the optical axis, both the object-side and image-side surfaces751,752are aspheric, and the fifth lens element750is made of plastic material.

The IR cut filter760made of glass is located between the fifth lens element750and the image plane770and has no influence on the focal length of the optical lens system.

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

FIG. 8Ashows an optical lens system in accordance with a eighth embodiment of the present invention, andFIG. 8Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the eighth embodiment of the present invention. An optical lens system in accordance with the eighth embodiment of the present invention comprises an aperture stop800and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element810, a second lens element820, a third lens element830, a fourth lens element840, a fifth lens element850, an IR cut filter860and an image plane870, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop800is located between an image-side surface812of the first lens element810and an object to be photographed.

The first lens element810with a positive refractive power has an object-side surface811being convex near the optical axis and the image-side surface812being concave near the optical axis, both the object-side and image-side surfaces811,812are aspheric, and the first lens element810is made of plastic material.

The second lens element820with a negative refractive power has an object-side surface821being convex near the optical axis and an image-side surface822being concave near the optical axis, both the object-side and image-side surfaces821,822are aspheric, and the second lens element820is made of plastic material.

The third lens element830with a positive refractive power has an object-side surface831being convex near the optical axis and an image-side surface832being concave near the optical axis, both the object-side and image-side surfaces831,832are aspheric, and the third lens element830is made of plastic material.

The fourth lens element840with a positive refractive power has an object-side surface841being concave near the optical axis and an image-side surface842being convex near the optical axis, both the object-side and image-side surfaces841,842are aspheric, and the fourth lens element840is made of plastic material.

The fifth lens element850with a negative refractive power has an object-side surface851being convex near the optical axis and an image-side surface852being concave near the optical axis, both the object-side and image-side surfaces851,852are aspheric, and the fifth lens element850is made of plastic material.

The IR cut filter860made of glass is located between the fifth lens element850and the image plane870and has no influence on the focal length of the optical lens system.

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

Moreover, these parameters can be calculated from Table 15 and Table 16 as the following values and satisfy the following conditions:

FIG. 9Ashows an optical lens system in accordance with a ninth embodiment of the present invention, andFIG. 9Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the ninth embodiment of the present invention. An optical lens system in accordance with the ninth embodiment of the present invention comprises an aperture stop900and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element910, a second lens element920, a third lens element930, a fourth lens element940, a fifth lens element950, an IR cut filter960and an image plane970, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop900is located between an image-side surface912of the first lens element910and an object to be photographed.

The first lens element910with a positive refractive power has an object-side surface911being convex near the optical axis and the image-side surface912being concave near the optical axis, both the object-side and image-side surfaces911,912are aspheric, and the first lens element910is made of plastic material.

The second lens element920with a negative refractive power has an object-side surface921being concave near the optical axis and an image-side surface922being concave near the optical axis, both the object-side and image-side surfaces921,922are aspheric, and the second lens element920is made of plastic material.

The third lens element930with a positive refractive power has an object-side surface931being convex near the optical axis and an image-side surface932being concave near the optical axis, both the object-side and image-side surfaces931,932are aspheric, and the third lens element930is made of plastic material.

The fourth lens element940with a positive refractive power has an object-side surface941being concave near the optical axis and an image-side surface942being convex near the optical axis, both the object-side and image-side surfaces941,942are aspheric, and the fourth lens element940is made of plastic material.

The fifth lens element950with a negative refractive power has an object-side surface951being convex near the optical axis and an image-side surface952being concave near the optical axis, both the object-side and image-side surfaces951,952are aspheric, and the fifth lens element950is made of plastic material.

The IR cut filter960made of glass is located between the fifth lens element950and the image plane970and has no influence on the focal length of the optical lens system.

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

Moreover, these parameters can be calculated from Table 17 and Table 18 as the following values and satisfy the following conditions:

FIG. 10Ashows an optical lens system in accordance with a tenth embodiment of the present invention, andFIG. 10Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the tenth embodiment of the present invention. An optical lens system in accordance with the tenth embodiment of the present invention comprises an aperture stop1000and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element1010, a second lens element1020, a third lens element1030, a fourth lens element1040, a fifth lens element1050, an IR cut filter1060and an image plane1070, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop1000is located between an image-side surface1012of the first lens element1010and an object to be photographed.

The first lens element1010with a positive refractive power has an object-side surface1011being convex near the optical axis and the image-side surface1012being convex near the optical axis, both the object-side and image-side surfaces1011,1012are aspheric, and the first lens element1010is made of plastic material.

The second lens element1020with a negative refractive power has an object-side surface1021being convex near the optical axis and an image-side surface1022being concave near the optical axis, both the object-side and image-side surfaces1021,1022are aspheric, and the second lens element1020is made of plastic material.

The third lens element1030with a positive refractive power has an object-side surface1031being concave near the optical axis and an image-side surface1032being convex near the optical axis, both the object-side and image-side surfaces1031,1032are aspheric, and the third lens element1030is made of plastic material.

The fourth lens element1040with a positive refractive power has an object-side surface1041being concave near the optical axis and an image-side surface1042being convex near the optical axis, both the object-side and image-side surfaces1041,1042are aspheric, and the fourth lens element1040is made of plastic material.

The fifth lens element1050with a negative refractive power has an object-side surface1051being convex near the optical axis and an image-side surface1052being concave near the optical axis, both the object-side and image-side surfaces1051,1052are aspheric, and the fifth lens element1050is made of plastic material.

The IR cut filter1060made of glass is located between the fifth lens element1050and the image plane1070and has no influence on the focal length of the optical lens system.

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

Moreover, these parameters can be calculated from Table 19 and Table 20 as the following values and satisfy the following conditions:

FIG. 11Ashows an optical lens system in accordance with a eleventh embodiment of the present invention, andFIG. 11Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the eleventh embodiment of the present invention. An optical lens system in accordance with the eleventh embodiment of the present invention comprises an aperture stop1100and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element1110, a second lens element1120, a third lens element1130, a fourth lens element1140, a fifth lens element1150, an IR cut filter1160and an image plane1170, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop1100is located between an image-side surface1112of the first lens element1110and an object to be photographed.

The first lens element1110with a positive refractive power has an object-side surface1111being convex near the optical axis and an image-side surface1112being convex near the optical axis, both the object-side and image-side surfaces1111,1112are aspheric, and the first lens element1110is made of plastic material.

The second lens element1120with a negative refractive power has an object-side surface1121being convex near the optical axis and an image-side surface1122being concave near the optical axis, both the object-side and image-side surfaces1121,1122are aspheric, and the second lens element1120is made of plastic material.

The third lens element1130with a positive refractive power has an object-side surface1131being convex near the optical axis and an image-side surface1132being concave near the optical axis, both the object-side and image-side surfaces1131,1132are aspheric, and the third lens element1130is made of plastic material.

The fourth lens element1140with a positive refractive power has an object-side surface1141being concave near the optical axis and an image-side surface1142being convex near the optical axis, both the object-side and image-side surfaces1141,1142are aspheric, and the fourth lens element1140is made of plastic material.

The fifth lens element1150with a negative refractive power has an object-side surface1151being convex near the optical axis and an image-side surface1152being concave near the optical axis, both the object-side and image-side surfaces1151,1152are aspheric, and the fifth lens element1150is made of plastic material.

The IR cut filter1160made of glass is located between the fifth lens element1150and the image plane1170and has no influence on the focal length of the optical lens system.

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

Moreover, these parameters can be calculated from Table 21 and Table 22 as the following values and satisfy the following conditions:

FIG. 12Ashows an optical lens system in accordance with a twelfth embodiment of the present invention, andFIG. 12Bshows, in order from left to right, the longitudinal spherical aberration curves, the astigmatic field curves, and the distortion curve of the twelfth embodiment of the present invention. An optical lens system in accordance with the twelfth embodiment of the present invention comprises an aperture stop1200and an optical assembly. The optical assembly comprises, in order from an object side to an image side: a first lens element1210, a second lens element1220, a third lens element1230, a fourth lens element1240, a fifth lens element1250, an IR cut filter1260and an image plane1270, wherein the optical lens system has a total of five lens elements with refractive power. The aperture stop1200is located between an image-side surface1212of the first lens element1210and an object to be photographed.

The first lens element1210with a positive refractive power has an object-side surface1211being convex near the optical axis and an image-side surface1212being concave near the optical axis, both the object-side and image-side surfaces1211,1212are aspheric, and the first lens element1210is made of plastic material.

The second lens element1220with a negative refractive power has an object-side surface1221being convex near the optical axis and an image-side surface1222being concave near the optical axis, both the object-side and image-side surfaces1221,1222are aspheric, and the second lens element1220is made of plastic material.

The third lens element1230with a positive refractive power has an object-side surface1231being concave near the optical axis and an image-side surface1232being convex near the optical axis, both the object-side and image-side surfaces1231,1232are aspheric, and the third lens element1230is made of plastic material.

The fourth lens element1240with a positive refractive power has an object-side surface1241being concave near the optical axis and an image-side surface1242being convex near the optical axis, both the object-side and image-side surfaces1241,1242are aspheric, and the fourth lens element1240is made of plastic material.

The fifth lens element1250with a negative refractive power has an object-side surface1251being convex near the optical axis and an image-side surface1252being concave near the optical axis, both the object-side and image-side surfaces1251,1252are aspheric, and the fifth lens element1250is made of plastic material.

The IR cut filter1260made of glass is located between the fifth lens element1250and the image plane1270and has no influence on the focal length of the optical lens system.

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

Moreover, these parameters can be calculated from Table 23 and Table 24 as the following values and satisfy the following conditions:

In the present optical lens system, the lens elements can be made of plastic or glass. If the lens elements are made of plastic, the cost will be effectively reduced. If the lens elements are made of glass, there is more freedom in distributing the refractive power of the optical lens system. Plastic lens elements can have aspheric surfaces, which allow more design parameter freedom (than spherical surfaces), so as to reduce the aberration and the number of the lens elements, as well as the total track length of the optical lens system.

In the present optical lens system, if the object-side or the image-side surface of the lens elements with refractive power is convex and the location of the convex surface is not defined, the object-side or the image-side surface of the lens elements near the optical axis is convex. If the object-side or the image-side surface of the lens elements is concave and the location of the concave surface is not defined, the object-side or the image-side surface of the lens elements near the optical axis is concave.

The optical lens system of the present invention can be used in focusing optical systems and can obtain better image quality. The optical lens system of the present invention can also be used in electronic imaging systems, such as, 3D image capturing, digital camera, mobile device, digital flat panel or vehicle camera.

The embodiments depicted above and the appended drawings are exemplary and are not intended to be exhaustive or to limit the scope of the present disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings.