Optical image capturing system

The invention discloses a three-piece optical lens for capturing image and a three-piece optical module for capturing image, which include, along the optical axis in order from an object side to an image side, a first lens with positive refractive power having an object-side surface which can be convex; a second lens with refractive power; a third lens with refractive power; two surfaces of each of the three lenses can be both aspheric. The third lens can have positive refractive power, wherein an image-side surface thereof can be concave, and both surfaces thereof are aspheric; at least one surface of the third lens has an inflection point. The optical lens can increase aperture value and improve the imagining quality for use in compact cameras.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates generally to an optical system, and more particularly to a compact optical image capturing system for an electronic device.

2. Description of Related Art

In recent years, with the rise of portable electronic devices having camera functionalities, the demand for an optical image capturing system is raised gradually. The image sensing device of ordinary photographing camera is commonly selected from charge coupled device (CCD) or complementary metal-oxide semiconductor sensor (CMOS Sensor). In addition, as advanced semiconductor manufacturing technology enables the minimization of pixel size of the image sensing device, the development of the optical image capturing system towards the field of high pixels. Therefore, the requirement for high imaging quality is rapidly raised.

The conventional optical system of the portable electronic device usually has a two-piece lens. However, the optical system is asked to take pictures in a dark environment, in other words, the optical system is asked to have a large aperture. An optical system with large aperture usually has several problems, such as large aberration, poor image quality at periphery of the image, and hard to manufacture. In addition, an optical system of wide-angle usually has large distortion. Therefore, the conventional optical system provides high optical performance as required.

It is an important issue to increase the quantity of light entering the lens and the angle of field of the lens. In addition, the modern lens is also asked to have several characters, including high pixels, high image quality, small in size, and high optical performance.

BRIEF SUMMARY OF THE INVENTION

The aspect of preferred embodiment of the present disclosure directs to an optical image capturing system and an optical image capturing lens which use combination of refractive powers, convex and concave surfaces of three-piece optical lenses (the convex or concave surface in the disclosure denotes the geometrical shape of an image-side surface or an object-side surface of each lens on an optical axis) to increase the quantity of incoming light of the optical image capturing system, and to improve imaging quality for image formation, so as to be applied to minimized electronic products.

The term and its definition to the lens parameter in the preferred embodiment of the present are shown as below for further reference.

The lens parameter related to a length or a height in the lens element:

A height for image formation of the optical image capturing system is denoted by HOI. A height of the optical image capturing system is denoted by HOS. A distance from the object-side surface of the first lens element to the image-side surface of the third lens element is denoted by InTL. A distance from the image-side surface of the third lens to the image plane is denoted by InB. InTL+InB=HOS. A distance from the first lens element to the second lens element is denoted by IN12 (instance). A central thickness of the first lens element of the optical image capturing system on the optical axis is denoted by TP1 (instance).

The lens parameter related to a material in the lens:

An Abbe number of the first lens element in the optical image capturing system is denoted by NA1 (instance). A refractive index of the first lens element is denoted by Nd1 (instance).

The lens parameter related to a view angle in the lens:

A view angle is denoted by AF. Half of the view angle is denoted by HAF. A major light angle is denoted by MRA.

The lens parameter related to exit/entrance pupil in the lens

An entrance pupil diameter of the optical image capturing system is denoted by HEP.

The lens parameter related to a depth of the lens shape

A distance in parallel with an optical axis from a maximum effective semi diameter position to an axial point on the object-side surface of the third lens is denoted by InRS31 (instance). A distance in parallel with an optical axis from a maximum effective semi diameter position to an axial point on the image-side surface of the third lens is denoted by InRS32 (instance).

The lens parameter related to the lens shape:

A critical point C is a tangent point on a surface of a specific lens, and the tangent point is tangent to a plane perpendicular to the optical axis and the tangent point cannot be a crossover point on the optical axis. To follow the past, a distance perpendicular to the optical axis between a critical point C21 on the object-side surface of the second lens and the optical axis is HVT21 (instance). A distance perpendicular to the optical axis between a critical point C22 on the image-side surface of the second lens and the optical axis is HVT22 (instance). A distance perpendicular to the optical axis between a critical point C31 on the object-side surface of the third lens and the optical axis is HVT31 (instance). A distance perpendicular to the optical axis between a critical point C32 on the image-side surface of the third lens and the optical axis is HVT32 (instance). The object-side surface of the third lens has one inflection point IF311 which is nearest to the optical axis, and the sinkage value of the inflection point IF311 is denoted by SGI311. A distance perpendicular to the optical axis between the inflection point IF311 and the optical axis is HIF311 (instance). The image-side surface of the third lens has one inflection point IF321 which is nearest to the optical axis, and the sinkage value of the inflection point IF321 is denoted by SG1321 (instance). A distance perpendicular to the optical axis between the inflection point IF321 and the optical axis is HIF321 (instance). The object-side surface of the third lens has one inflection point IF312 which is the second nearest to the optical axis, and the sinkage value of the inflection point IF312 is denoted by SG1312 (instance). A distance perpendicular to the optical axis between the inflection point IF312 and the optical axis is HIF312 (instance). The image-side surface of the third lens has one inflection point IF322 which is the second nearest to the optical axis, and the sinkage value of the inflection point IF322 is denoted by SG1322 (instance). A distance perpendicular to the optical axis between the inflection point IF322 and the optical axis is HIF322 (instance).

The lens element parameter related to an aberration:

Optical distortion for image formation in the optical image capturing system is denoted by ODT. TV distortion for image formation in the optical image capturing system is denoted by TDT. Further, the range of the aberration offset for the view of image formation may be limited to 50%-100% field. An offset of the spherical aberration is denoted by DFS. An offset of the coma aberration is denoted by DFC.

The present invention provides an optical image capturing system, in which the third lens is provided with an inflection point at the object-side surface or at the image-side surface to adjust the incident angle of each view field and modify the ODT and the TDT. In addition, the surfaces of the third lens are capable of modifying the optical path to improve the imagining quality.

The optical image capturing system of the present invention includes a first lens, a second lens, and a third lens in order along an optical axis from an object side to an image side. The first lens has positive refractive power, and the third lens has refractive power. At least two lenses among the three lenses respectively have at least an inflection point on at least one surface thereof. Both the object-side surface and the image-side surface of the third lens are aspheric surfaces. The optical image capturing system satisfies:
1.2≦f/HEP≦6.0 and 1.0≦HOS/f≦2.0;

where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; and HOS is a distance in parallel with the optical axis between an object-side surface, which face the object side, of the first lens and the image plane.

The present invention further provides an optical image capturing system, including a first lens, a second lens, and a third lens in order along an optical axis from an object side to an image side. The first lens has positive refractive power, and both the object-side surface and the image-side surface thereof are aspheric surfaces. The second lens has refractive power, and at least one surface thereof has at least an inflection point. The third lens has refractive power, and at least one surface thereof has at least an inflection point, wherein both an object-side surface and an image-side surface thereof are aspheric surfaces. The optical image capturing system satisfies:
1.2≦f/HEP≦6.0; 0.4≦| tan(HAF)|≦1.0; 1.0≦HOS/f≦2.0; |TDT|<60%; and |ODT|≦50%;

where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; HOS is a distance in parallel with the optical axis between an object-side surface, which face the object side, of the first lens and the image plane; HAF is a half of the view angle of the optical image capturing system; TDT is a TV distortion; and ODT is an optical distortion.

The present invention further provides an optical image capturing system, including a first lens, a second lens, and a third lens in order along an optical axis from an object side to an image side. The first lens has positive refractive power, and an image-side surface thereof is convex near the optical axis; at least one surface among an object-side surface and the image-side surface of the first lens has at least an inflection point. The second and has negative refractive power, and at least one surface among an object-side surface and an image-side surface thereof has at least an inflection point. The third lens has refractive power, wherein at least one surface among an object-side surface and an image-side surface thereof has at least an inflection point, and both the object-side surface and the image side surface thereof are aspheric surfaces. The optical image capturing system satisfies:
1.2≦f/HEP≦3.0; 0.4≦| tan(HAF)|≦1.0; 1.0≦HOS/f≦2.0; |TDT|<60%; and |ODT|≦50%;

where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; HOS is a distance in parallel with the optical axis between an object-side surface, which face the object side, of the first lens and the image plane; HAF is a half of the view angle of the optical image capturing system; TDT is a TV distortion; and ODT is an optical distortion.

In an preferred embodiment, the optical image capturing system further includes an image sensor with a size less than 1/1.2″ in diagonal, and a pixel less than 1.4 μm. A preferable size is 1/2.3″, and a preferable pixel size of the image sensor is less than 1.12 μm, and more preferable pixel size is less than 0.9 μm. A 16:9 image sensor is available for the optical image capturing system of the present invention.

In an preferred embodiment, the optical image capturing system of the present invention is available to high-quality recording which requires more than 1 megapixel, and provides high quality of image.

In an preferred embodiment, a height of the optical image capturing system (HOS) can be reduced while |f1|>f3.

In an preferred embodiment, if the lenses satisfy |f2|>|f1|, the second lens has weak positive refractive power or weak negative refractive power. If the second lens has weak positive refractive power, it may share the positive refractive power of the first lens, and on the contrary, if the second lens has weak negative refractive power, it may finely correct the aberration of the system.

In an preferred embodiment, the third lens can have positive refractive power, and an image-side surface thereof can be concave, it may reduce back focal length and size. Besides, the third lens has at least an inflection point on at least a surface thereof, which may reduce an incident angle of the light of an off-axis field of view and correct the aberration of the off-axis field of view.

DETAILED DESCRIPTION OF THE INVENTION

An optical image capturing system of the present invention includes a first lens, a second lens, and a third lens from an object side to an image side. The optical image capturing system further is provided with an image sensor at an image plane.

The optical image capturing system works in three wavelengths, including 486.1 nm, 587.5 nm, and 656.2 nm, wherein 587.5 mm is the main reference wavelength, and 555 nm is adopted as the main reference wavelength for extracting features.

The optical image capturing system of the present invention satisfies 0.5≦ΣPPR/|ΣNPR|≦4.5, and a preferable range is 1≦ΣPPR/|ΣNPR|≦3.8, where PPR is a ratio of the focal length f of the optical image capturing system to a focal length fp of each of lenses with positive refractive power; NPR is a ratio of the focal length fn of the optical image capturing system to a focal length fn of each of lenses with negative refractive power; ΣPPR is a sum of the PPRs of each positive lens, and ΣNPR is a sum of the NPRs of each negative lens. It is helpful for control of an entire refractive power and an entire length of the optical image capturing system.

HOS is a height of the optical image capturing system, and when the ratio of HOS/f approaches to 1, it is helpful for decrease of size and increase of imaging quality.

In an preferred embodiment, the optical image capturing system of the present invention satisfies 0<ΣPP≦200 and f1/ΣPP≦0.85, and a preferable range is 0<ΣPP≦150 and 0.01≦f1/ΣPP≦0.6, where ΣPP is a sum of a focal length fp of each lens with positive refractive power, and ΣNP is a sum of a focal length fn of each lens with negative refractive power. It is helpful for control of focusing capacity of the system and redistribution of the positive refractive powers of the system to avoid the significant aberration in early time. The first lens has positive refractive power, and an object-side surface, which faces the object side, thereof can be convex. It may modify the positive refractive power of the first lens as well as shorten the entire length of the system.

The second lens can have negative refractive power, which may correct the aberration of the first lens.

The third lens can have positive refractive power, and an image-side surface thereof, which faces the image side, can be concave. It may share the positive refractive power of the first lens, and shorten a rear focal length to reduce the size of the system. In addition, the third lens is provided with at least an inflection point on at least a surface to reduce an incident angle of the light of an off-axis field of view and correct the aberration of the off-axis field of view. It is preferable that each surface, the object-side surface and the image-side surface, of the third lens has at least an inflection point.

The image sensor is provided on the image plane. The optical image capturing system of the present invention satisfies HOS/HOI≦3 and 0.5≦HOS/f≦3.0, and a preferable range is 1≦HOS/HOI≦2.5 and 1≦HOS/f≦2, where HOI is height for image formation of the optical image capturing system, i.e., the maximum image height, and HOS is a height of the optical image capturing system, i.e., a distance on the optical axis between the object-side surface of the first lens and the image plane. It is helpful for reduction of size of the system for used in compact cameras.

The optical image capturing system of the present invention further is provided with an aperture to increase image quality.

In the optical image capturing system of the present invention, the aperture could be a front aperture or a middle aperture, wherein the front aperture is provided between the object and the first lens, and the middle is provided between the first lens and the image plane. The front aperture provides a long distance between an exit pupil of the system and the image plane, which allows more elements to be installed. The middle could enlarge a view angle of view of the system and increase the efficiency of the image sensor. The optical image capturing system satisfies 0.5≦InS/HOS≦1.1, and a preferable range is 0.6≦InS/HOS≦1, where InS is a distance between the aperture and the image plane. It is helpful for size reduction and wide angle.

The optical image capturing system of the present invention satisfies 0.45≦ΣTP/InTL≦0.95, where InTL is a distance between the object-side surface of the first lens and the image-side surface of the third lens, and ΣTP is a sum of central thicknesses of the lenses on the optical axis. It is helpful for the contrast of image and yield of manufacture, and provides a suitable back focal length for installation of other elements.

The optical image capturing system of the present invention satisfies 0.1≦|R1/R2|≦3.0, and a preferable range is 0.1≦|R1/R2|≦2.0, where R1 is a radius of curvature of the object-side surface of the first lens, and R2 is a radius of curvature of the image-side surface of the first lens. It provides the first lens with a suitable positive refractive power to reduce the increase rate of the spherical aberration.

The optical image capturing system of the present invention satisfies −200<(R5−R6)/(R5+R6)<30, where R5 is a radius of curvature of the object-side surface of the third lens, and R6 is a radius of curvature of the image-side surface of the third lens. It may modify the astigmatic field curvature.

The optical image capturing system of the present invention satisfies 0<IN12/f≦0.30, and a preferable range is 0.01≦IN12/f≦0.25, where IN12 is a distance on the optical axis between the first lens and the second lens. It may correct chromatic aberration and improve the performance.

The optical image capturing system of the present invention satisfies 2≦(TP1+IN12)/TP2≦10, where TP1 is a central thickness of the first lens on the optical axis, and TP2 is a central thickness of the second lens on the optical axis. It may control the sensitivity of manufacture of the system and improve the performance.

The optical image capturing system of the present invention satisfies 1.0≦(TP3+IN23)/TP2≦10, where TP3 is a central thickness of the third lens on the optical axis, and IN23 is a distance between the second lens and the third lens. It may control the sensitivity of manufacture of the system and improve the performance.

The optical image capturing system of the present invention satisfies 0.1≦TP2/ΣTP≦0.9, and a preferable range is 0.01≦TP2/ΣTP≦0.3, where TP2 is a central thickness of the second lens on the optical axis, and ΣTP is a sum of the central thicknesses of all the lenses on the optical axis. It may finely correct the aberration of the incident rays and reduce the height of the system.

The optical image capturing system of the present invention satisfies −1 mm≦InRS31≦1 mm; −1 mm≦InRS32≦1 mm; 1 mm<|InRS31|+|InRS32|≦2 mm; 0.01≦|InRS31|/TP3≦10; and 0.01≦|InRS32|/TP3≦10, where InRS31 is a displacement in parallel with the optical axis from a point on the object-side surface of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the third lens, wherein InRS31 is positive while the displacement is toward the image side, and InRS31 is negative while the displacement is toward the object side; InRS32 is a displacement in parallel with the optical axis from a point on the image-side surface of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the third lens; and TP3 is a central thickness of the third lens on the optical axis. It may control the positions of the maximum effective semi diameter on both surfaces of the third lens, correct the aberration of the peripheral field of view, and reduce the size.

The optical image capturing system of the present invention satisfies 0<SGI311/(SGI311+TP3)≦0.9 and 0<SGI521/(SGI321+TP3)≦0.9, and a preferable range is 0.01<SGI311/(SGI311+TP3)≦0.7 and 0.01<SGI321/(SGI321+TP3)≦0.7, where SGI311 is a displacement in parallel with the optical axis from a point on the object-side surface of the third lens, through which the optical axis passes, to an inflection point, which is the closest to the optical axis, on the object-side surface of the third lens; SGI321 is a displacement in parallel with the optical axis from a point on the image-side surface of the third lens, through which the optical axis passes, to an inflection point, which is the closest to the optical axis, on the image-side surface of the third lens, and TP3 is a thickness of the third lens on the optical axis.

The optical image capturing system of the present invention satisfies 0<SGI312/(SGI312+TP3)≦0.9 and 0<SGI322/(SGI322+TP3)≦0.9, and a preferable range is 0.1SGI312/(SGI312+TP3)≦0.8 and 0.1SGI322/(SGI322+TP3)≦0.8, where SGI312 is a displacement in parallel with the optical axis from a point on the object-side surface of the third lens, through which the optical axis passes, to an inflection point, which is the second closest to the optical axis, on the image-side surface of the third lens, and SGI322 is a displacement in parallel with the optical axis from a point on the object-side surface of the third lens, through which the optical axis passes, to an inflection point, which is the second closest to the optical axis, on the image-side surface of the third lens.

The optical image capturing system of the present invention satisfies 0.01≦‘HIF311/HOI≦0.9 and 0.01≦HIF321/HOI≦0.9, and a preferable range is 0.09≦HIF311/HOI≦0.5 and 0.09≦HIF321/HOI≦0.5, where HIF311 is a distance perpendicular to the optical axis between the inflection point, which is the closest to the optical axis, on the object-side surface of the third lens and the optical axis, and HIF321 is a distance perpendicular to the optical axis between the inflection point, which is the closest to the optical axis, on the image-side surface of the third lens and the optical axis.

The optical image capturing system of the present invention satisfies 0.01≦HIF312/HOI≦0.9 and 0.01≦HIF322/HOI≦0.9, and a preferable range is 0.09≦HIF312/HOI≦0.8 and 0.09≦HIF322/HOI≦0.8, where HIF312 is a distance perpendicular to the optical axis between the inflection point, which is the second the closest to the optical axis, on the object-side surface of the third lens and the optical axis, and HIF322 is a distance perpendicular to the optical axis between the inflection point, which is the second the closest to the optical axis, on the image-side surface of the third lens and the optical axis.

In an preferred embodiment, the lenses of high Abbe number and the lenses of low Abbe number are arranged in an interlaced arrangement that could be helpful for correction of aberration of the system.

An equation of aspheric surface is
z=ch2/[1+[1(k+1)c2h2]0.5]+A4h4+A6h6+A8h8+A10h10+A12h12+A14h14+A16h16+A18h18+A20h20+  (1)

where z is a depression of the aspheric surface; k is conic constant; c is reciprocal of radius of curvature; and A4, A6, A8, A10, A12, A14, A16, A18, and A20 are high-order aspheric coefficients.

In the optical image capturing system, the lenses could be made of plastic or glass. The plastic lenses may reduce the weight and lower the cost of the system, and the glass lenses may control the thermal effect and enlarge the space for arrangement of refractive power of the system. In addition, the opposite surfaces (object-side surface and image-side surface) of the first to the third lenses could be aspheric that can obtain more control parameters to reduce aberration. The number of aspheric glass lenses could be less than the conventional spherical glass lenses that is helpful for reduction of the height of the system.

When the lens has a convex surface, which means that the surface is convex around a position, through which the optical axis passes, and when the lens has a concave surface, which means that the surface is concave around a position, through which the optical axis passes.

The optical image capturing system of the present invention further is provided with a diaphragm to increase image quality.

In the optical image capturing system, the diaphragm could be a front diaphragm or a middle diaphragm, wherein the front diaphragm is provided between the object and the first lens, and the middle is provided between the first lens and the image plane. The front diaphragm provides a long distance between an exit pupil of the system and the image plane, which allows more elements to be installed. The middle diaphragm could enlarge a view angle of view of the system and increase the efficiency of the image sensor. The middle diaphragm is helpful for size reduction and wide angle.

The optical image capturing system of the present invention could be applied in dynamic focusing optical system. It is superior in correction of aberration and high imaging quality so that it could be allied in lots of fields.

We provide several preferred embodiments in conjunction with the accompanying drawings for the best understanding, which are:

First Preferred Embodiment

As shown inFIG. 1AandFIG. 1B, an optical image capturing system100of the first preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens110, an aperture100, a second lens120, a third lens130, an infrared rays filter170, an image plane180, and an image sensor190.

The first lens110has positive refractive power, and is made of plastic. An object-side surface112thereof, which faces the object side, is a convex aspheric surface, and an image-side surface114thereof, which faces the image side, is a concave aspheric surface.

The second lens120has negative refractive power, and is made of plastic. An object-side surface122thereof, which faces the object side, is a concave aspheric surface, and an image-side surface124thereof, which faces the image side, is a convex aspheric surface, and the image-side surface124has an inflection point. The second lens120satisfies SGI221=−0.1526 mm and |SGI221|/(|SGI221|+TP2)=0.2292, where SGI221 is a displacement in parallel with the optical axis from a point on the image-side surface of the second lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.

The second lens further satisfies HIF221=0.5606 mm and HIF221/HOI=0.3128, where HIF221 is a displacement perpendicular to the optical axis from a point on the image-side surface of the second lens, through which the optical axis passes, to the inflection point, which is the closest to the optical axis.

The third lens130has positive refractive power, and is made of plastic. An object-side surface132, which faces the object side, is a convex aspheric surface, and an image-side surface134, which faces the image side, is a concave aspheric surface. The object-side surface132has two inflection points, and the image-side surface134has an inflection point. The third lens130satisfies SGI311=−0.0180 mm; SGI321=−0.0331 mm and |SGI311|/(|SGI311|+TP3)=0.0339 and |SGI321|/(|SGI321|+TP3)=0.0605, where SGI311 is a displacement in parallel with the optical axis, from a point on the object-side surface of the third lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the closest to the optical axis, and SGI321 is a displacement in parallel with the optical axis, from a point on the image-side surface of the third lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.

The third lens130satisfies SGI312=−0.0367 mm; |SGI312|/(|SGI312|+TP3)=0668, where SGI312 is a displacement in parallel with the optical axis, from a point on the object-side surface of the third lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the second closest to the optical axis.

The third lens130further satisfies HIF311=0.2298 mm; HIF321=0.3393 mm; HIF311/HOI=0.1282; and HIF321/HOI=0.1893, where HIF311 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the third lens, which is the closest to the optical axis, and the optical axis, and HIF321 is a distance perpendicular to the optical axis between the inflection point on the image-side surface of the third lens, which is the closest to the optical axis, and the optical axis.

The third lens130further satisfies HIF312=0.8186 mm; HIF312/HOI=0.4568, where HIF312 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the third lens, which is the second the closest to the optical axis, and the optical axis.

The infrared rays filter170is made of glass, and between the third lens130and the image plane180. The infrared rays filter170gives no contribution to the focal length of the system.

The optical image capturing system of the first preferred embodiment has the following parameters, which are f=2.42952 mm; f/HEP=2.02; and HAF=35.87 degrees and tan(HAF)=0.7231, where f is a focal length of the system; HAF is a half of the maximum field angle; and HEP is an entrance pupil diameter.

The parameters of the lenses of the first preferred embodiment are f1=2.27233 mm; |f/f1|=1.0692; f3=7.0647 mm; |f1|≦f3; and |f1/f3|=0.3216, where f1 is a focal length of the first lens110; and f3 is a focal length of the third lens130.

The first preferred embodiment further satisfies f2=−5.2251 mm; and |f2|>|f1|, where f2 is a focal length of the second lens120, and f3 is a focal length of the third lens130.

The optical image capturing system of the first preferred embodiment further satisfies ΣPPR=f/f1+f/f3=1.4131; ΣNPR=f/f2=0.4650; ΣPPR/|ΣNPR|=3.0391; |f/f3|=0.3439; |f1/f2|=0.4349; |f2/f3|=0.7396, where PPR is a ratio of a focal length f of the optical image capturing system to a focal length fp of each of the lenses with positive refractive power; and NPR is a ratio of a focal length fn of the optical image capturing system to a focal length fn of each of lenses with negative refractive power.

The optical image capturing system of the first preferred embodiment further satisfies InTL+InB=HOS; HOS=2.9110 mm; HOI=1.792 mm; HOS/HOI=1.6244; HOS/f=1.1982; InTL/HOS=0.7008; InS=2.25447 mm; and InS/HOS=0.7745, where InTL is a distance between the object-side surface112of the first lens110and the image-side surface134of the third lens130; HOS is a height of the image capturing system, i.e., a distance between the object-side surface112of the first lens110and the image plane180; InS is a distance between the aperture100and the image plane180; HOI is height for image formation of the optical image capturing system, i.e., the maximum image height; and InB is a distance between the image-side surface134of the third lens130and the image plane180.

The optical image capturing system of the first preferred embodiment further satisfies ΣTP=1.4198 mm and ΣTP/InTL=0.6959, where ΣTP is a sum of the thicknesses of the lenses110-130with refractive power. It is helpful for the contrast of image and yield of manufacture, and provides a suitable back focal length for installation of other elements.

The optical image capturing system of the first preferred embodiment further satisfies |R1/R2|=0.3849, where R1 is a radius of curvature of the object-side surface112of the first lens110, and R2 is a radius of curvature of the image-side surface114of the first lens110. It provides the first lens with a suitable positive refractive power to reduce the increase rate of the spherical aberration.

The optical image capturing system of the first preferred embodiment further satisfies (R5−R6)/(R5+R6)=−0.0899, where R5 is a radius of curvature of the object-side surface132of the third lens130, and R6 is a radius of curvature of the image-side surface134of the third lens130. It may modify the astigmatic field curvature.

The optical image capturing system of the first preferred embodiment further satisfies ΣPP=f1+f3=9.3370 mm and f1/(f1+f3)=0.2434, where ΣPP is a sum of the focal lengths fp of each lens with positive refractive power. It is helpful to share the positive refractive power of the first lens110to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the first preferred embodiment further satisfies ΣNP=f2=−5.2251 mm, where f2 is a focal length of the second lens120, and ΣNP is a sum of the focal lengths fn of each lens with negative refractive power. It is helpful to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the first preferred embodiment further satisfies IN12=0.4068 mm and IN12/f=0.1674, where IN12 is a distance on the optical axis between the first lens110and the second lens120. It may correct chromatic aberration and improve the performance.

The optical image capturing system of the first preferred embodiment further satisfies TP1=0.5132 mm; TP2=0.3363 mm; and (TP1+IN12)/TP2=2.7359, where TP1 is a central thickness of the first lens110on the optical axis, and TP2 is a central thickness of the second lens120on the optical axis. It may control the sensitivity of manufacture of the system and improve the performance.

The optical image capturing system of the first preferred embodiment further satisfies (TP3+IN23)/TP2=2.3308, where IN23 is a distance on the optical axis between the second lens120and the third lens130. It may control the sensitivity of manufacture of the system and improve the performance.

The optical image capturing system of the first preferred embodiment further satisfies TP2/ΣTP=0.2369, where TP2 is a thickness on the optical axis of the second lens120, and ΣTP is a sum of the central thicknesses of all the lenses with refractive power on the optical axis. It may finely correct the aberration of the incident rays and reduce the height of the system.

The optical image capturing system of the first preferred embodiment further satisfies InRS31=−0.1097 mm; InRS32=−0.3195 mm; |InRS31|+|InRS32|=0.42922 mm; |InRS31|/TP3=0.1923; and |InRS32|/TP3=0.5603,where InRS31 is a displacement in parallel with the optical axis from a point on the object-side surface132of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface132of the third lens130; InRS32 is a displacement in parallel with the optical axis from a point on the image-side surface134of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface134of the third lens130; and TP3 is a central thickness of the third lens130on the optical axis. It is helpful for manufacturing and shaping of the lenses, and is helpful to reduce the size.

The optical image capturing system of the first preferred embodiment further satisfies HVT31=0.4455 mm; HVT32=0.6479 mm; and HVT31/HVT32=0.6876, wherein a distance perpendicular to the optical axis between a critical point C31 on the object-side surface132of the third lens130and the optical axis is HVT31; a distance perpendicular to the optical axis between a critical point C32 on the image-side surface134of the third lens130and the optical axis is HVT32. It is helpful to correct the aberration of the off-axis field of view.

The optical image capturing system of the first preferred embodiment further satisfies HVT32/HOI=0.3616. It is helpful to correct the aberration of the peripheral field of view.

The optical image capturing system of the first preferred embodiment further satisfies HVT32/HOS=0.2226. It is helpful to correct the aberration of the peripheral field of view.

The second lens120and the third lens130of the optical image capturing system of the first preferred embodiment have negative refractive power, and the optical image capturing system further satisfies |NA1−NA2|=33.5951; and NA3/NA2=2.4969, where NA1 is an Abbe number of the first lens110, NA2 is an Abbe number of the second lens120, and NA3 is an Abbe number of the third lens130. It may correct the aberration of the system.

The optical image capturing system of the first preferred embodiment further satisfies |TDT|=1.2939% and |ODT|=1.4381%, where TDT is TV distortion; and ODT is optical distortion.

The parameters of the lenses of the first preferred embodiment are listed in Table 1 and Table 2.

The detail parameters of the first preferred embodiment are listed in Table 1, in which the unit of radius of curvature, thickness, and focal length are millimeter, and surface 0-10 indicates the surfaces of all elements in the system in sequence from the object side to the image side. Table 2 is the list of coefficients of the aspheric surfaces, in which A1-A20 indicate the coefficients of aspheric surfaces from the first order to the twentieth order of each aspheric surface. The following preferred embodiments have the similar diagrams and tables, which are the same as those of the first preferred embodiment, so we do not describe it again.

Second Preferred Embodiment

As shown inFIG. 2AandFIG. 2B, an optical image capturing system of the second preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens210, an aperture200, a second lens220, a third lens230, an infrared rays filter270, an image plane280, and an image sensor290.

The first lens210has positive refractive power, and is made of plastic. An object-side surface212thereof, which faces the object side, is a convex aspheric surface, and an image-side surface214thereof, which faces the image side, is a convex aspheric surface. The object-side surface212and the image-side surface214both have an inflection point thereon.

The second lens220has negative refractive power, and is made of plastic. An object-side surface222thereof, which faces the object side, is a concave aspheric surface, and an image-side surface224thereof, which faces the image side, is a convex aspheric surface. The object-side surface222has two inflection points thereon, and the image-side surface224has an inflection point thereon.

The third lens230has positive refractive power, and is made of plastic. An object-side surface232, which faces the object side, is a convex aspheric surface, and an image-side surface234, which faces the image side, is a concave aspheric surface. The object-side surface232and the image-side surface both have an inflection point thereon.

The infrared rays filter270is made of glass, and between the third lens230and the image plane280. The infrared rays filter270gives no contribution to the focal length of the system.

The optical image capturing system of the second preferred embodiment has the following parameters, which are |f2|=2.578 mm; |f1|=2.229 mm; and |f2|>|f1|, where f1 is a focal length of the first lens210; f2 is a focal length of the second lens220.

The optical image capturing system of the second preferred embodiment further satisfies TP2=0.246 mm and TP3=1.019 mm, where TP2 is a thickness of the second lens220on the optical axis, and TP3 is a thickness of the third lens230on the optical axis.

In the second preferred embodiment, the first and the third lenses210,230are positive lenses, and their focal lengths are f1 and f3 respectively. The optical image capturing system of the second preferred embodiment further satisfies ΣPP=f1+f3=6.4340 mm and f1/(f1+f3)=0.3465, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens210to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the second preferred embodiment further satisfies ΣNP=f2, where f2 is the focal length of the second lens220, and ΣNP is a sum of the focal lengths of each negative lens.

The parameters of the lenses of the second preferred embodiment are listed in Table 3 and Table 4.

An equation of the aspheric surfaces of the second preferred embodiment is the same as that of the first preferred embodiment, and the definitions are the same as well.

The exact parameters of the second preferred embodiment (with 555 nm as the main reference wavelength) based on Table 3 and Table 4 are listed in the following table:

The exact parameters related to inflection points of the second preferred embodiment (with main reference wavelength as 555 nm) based on Table 3 and Table 4 are listed in the following table:

Third Preferred Embodiment

As shown inFIG. 3AandFIG. 3B, an optical image capturing system of the third preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens310, an aperture300, a second lens320, a third lens330, an infrared rays filter370, an image plane380, and an image sensor390.

The first lens310has positive refractive power, and is made of plastic. An object-side surface312thereof, which faces the object side, is a convex aspheric surface, and an image-side surface314thereof, which faces the image side, is a convex aspheric surface. The object-side surface312has two inflection points thereon.

The second lens320has negative refractive power, and is made of plastic. An object-side surface322thereof, which faces the object side, is a concave aspheric surface; while an image-side surface324thereof, which faces the image side, is a convex aspheric surface. The object-side surface322and the image-side surface324both have an inflection point thereon.

The third lens330has positive refractive power, and is made of plastic. An object-side surface332, which faces the object side, is a convex aspheric surface, and an image-side surface334, which faces the image side, is a concave aspheric surface. The object-side surface332and the image-side surface334both have an inflection point thereon.

The infrared rays filter370is made of glass, and between the third lens330and the image plane380. The infrared rays filter370gives no contribution to the focal length of the system.

The parameters of the lenses of the third preferred embodiment are |f2|=2.250 mm, and |f1|=2.275 mm, where f1 is a focal length of the first lens310; f2 is a focal length of the second lens320.

The optical image capturing system of the third preferred embodiment further satisfies TP2=0.227 mm and TP3=1.258 mm, where TP2 is a thickness of the second lens320on the optical axis, and TP3 is a thickness of the third lens330on the optical axis.

In the third preferred embodiment, the first and the third lenses310,330are positive lenses, and their focal lengths are f1 and f3 respectively. The optical image capturing system of the third preferred embodiment further satisfies ΣPP=f1+f3=5.4556 mm and f1/(f1+f3)=0.4170, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens310to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the third preferred embodiment further satisfies ΣNP=f2, where ΣNP is a sum of the focal lengths of each negative lens.

The parameters of the lenses of the third preferred embodiment are listed in Table 5 and Table 6.

An equation of the aspheric surfaces of the third preferred embodiment is the same as that of the first preferred embodiment, and the definitions are the same as well.

The exact parameters of the third preferred embodiment (with 555 nm as the main reference wavelength) based on Table 5 and Table 6 are listed in the following table:

The exact parameters related to inflection points of the third preferred embodiment (with main reference wavelength as 555 nm) based on Table 5 and Table 6 are listed in the following table:

Fourth Preferred Embodiment

As shown inFIG. 4AandFIG. 4B, an optical image capturing system of the fourth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens410, an aperture400, a second lens420, a third lens430, an infrared rays filter470, an image plane480, and an image sensor490.

The first lens410has positive refractive power, and is made of plastic. An object-side surface412thereof, which faces the object side, is a convex aspheric surface, and an image-side surface414thereof, which faces the image side, is a convex aspheric surface. The object-side surface412has an inflection point thereon.

The second lens420has negative refractive power, and is made of plastic. An object-side surface422thereof, which faces the object side, is a concave aspheric surface, and an image-side surface424thereof, which faces the image side, is a convex aspheric surface. The object-side surface422and the image-side surface424both have an inflection point thereon.

The third lens430has positive refractive power, and is made of plastic. An object-side surface432, which faces the object side, is a convex aspheric surface, and an image-side surface434, which faces the image side, is a concave aspheric surface. The object-side surface432and the image-side surface434both have one inflection point thereon.

The infrared rays filter470is made of glass, and between the third lens430and the image plane480. The infrared rays filter470gives no contribution to the focal length of the system.

The optical image capturing system of the fourth preferred embodiment has the following parameters, which are |f2|=2.629 mm; |f1|=2.450 mm; and |f2|>|f1|, where f1 is a focal length of the first lens410; f2 is a focal length of the second lens420.

The optical image capturing system of the fourth preferred embodiment further satisfies TP2=0.215 mm and TP3=1.444 mm, where TP2 is a thickness of the second lens420on the optical axis, and TP3 is a thickness of the third lens430on the optical axis.

In the fourth preferred embodiment, the first and the third lenses410,430are positive lenses, and their focal lengths are f1 and f3 respectively. The optical image capturing system of the fourth preferred embodiment further satisfies ΣPP=f1+f3=5.70439 mm and f1/(f1+f3)=0.42948, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens410to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the fourth preferred embodiment further satisfies ΣNP=f2, where f2 is a focal length of the second lens420, and ΣNP is a sum of the focal lengths of each negative lens.

The parameters of the lenses of the fourth preferred embodiment are listed in Table 7 and Table 8.

An equation of the aspheric surfaces of the fourth preferred embodiment is the same as that of the first preferred embodiment, and the definitions are the same as well.

The exact parameters of the fourth preferred embodiment (with 555 nm as the main reference wavelength) based on Table 7 and Table 8 are listed in the following table:

The exact parameters related to inflection points of the fourth preferred embodiment (with main reference wavelength as 555 nm) based on Table 7 and Table 8 are listed in the following table:

Fifth Preferred Embodiment

As shown inFIG. 5AandFIG. 5B, an optical image capturing system of the fifth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture500, a first lens510, a second lens520, a third lens530, an infrared rays filter570, an image plane580, and an image sensor590.

The first lens510has positive refractive power, and is made of plastic. An object-side surface512thereof, which faces the object side, is a convex aspheric surface, and an image-side surface514thereof, which faces the image side, is a concave aspheric surface.

The second lens520has positive refractive power, and is made of plastic. An object-side surface522thereof, which faces the object side, is a concave aspheric surface, and an image-side surface524thereof, which faces the image side, is a convex aspheric surface. The image-side surface524has two inflection points.

The third lens530has negative refractive power, and is made of plastic. An object-side surface532, which faces the object side, is a convex aspheric surface, and an image-side surface534, which faces the image side, is a concave aspheric surface. The object-side surface has three inflection points thereon, and the image-side surface534has an inflection point thereon.

The infrared rays filter570is made of glass, and between the third lens530and the image plane580. The infrared rays filter570gives no contribution to the focal length of the system.

The parameters of the lenses of the fifth preferred embodiment are |f2|=1.387 mm; |f1|=1.452 mm; and |f2|<|f1|, where f1 is a focal length of the first lens510; f2 is a focal length of the second lens520.

The optical image capturing system of the fifth preferred embodiment further satisfies TP2=0.242 mm and TP3=0.294 mm, where TP2 is a thickness of the second lens520on the optical axis, and TP3 is a thickness of the third lens530on the optical axis.

In the fifth preferred embodiment, the first and the second lenses510,520are positive lenses, and their focal lengths are f1 and f2 respectively. The optical image capturing system of the fifth preferred embodiment further satisfies ΣPP=f1+f2=2.83947 mm and f1/(f1+f2)=0.51149, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens510to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the fifth preferred embodiment further satisfies ΣNP=f3, where ΣNP is a sum of the focal lengths of each negative lens.

The parameters of the lenses of the fifth preferred embodiment are listed in Table 9 and Table 10.

An equation of the aspheric surfaces of the fifth preferred embodiment is the same as that of the first preferred embodiment, and the definitions are the same as well.

The exact parameters of the fifth preferred embodiment (with 555 nm as the main reference wavelength) based on Table 9 and Table 10 are listed in the following table:

The exact parameters related to inflection points of the fifth preferred embodiment (with main reference wavelength as 555 nm) based on Table 9 and Table 10 are listed in the following table:

Sixth Preferred Embodiment

As shown inFIG. 6AandFIG. 6B, an optical image capturing system of the sixth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture600, a first lens610, a second lens620, a third lens630, an infrared rays filter670, an image plane680, and an image sensor690.

The first lens610has positive refractive power, and is made of plastic. An object-side surface612thereof, which faces the object side, is a convex aspheric surface, and an image-side surface614thereof, which faces the image side, is a convex aspheric surface. The object-side surface612has an inflection point thereon.

The second lens620has negative refractive power, and is made of plastic. An object-side surface622thereof, which faces the object side, is a concave aspheric surface, and an image-side surface624thereof, which faces the image side, is a convex aspheric surface. The object-side surface622and the image-side surface624both have an inflection point thereon.

The third lens630has positive refractive power, and is made of plastic. An object-side surface632, which faces the object side, is a convex aspheric surface, and an image-side surface634, which faces the image side, is a concave aspheric surface. The object-side surface632and the image-side surface634both have an inflection point thereon.

The infrared rays filter670is made of glass, and between the third lens630and the image plane680. The infrared rays filter670gives no contribution to the focal length of the system.

The parameters of the lenses of the sixth preferred embodiment are |f2|=1.706 mm; |f1|=1.791 mm; and |f2|<|f1|, where f1 is a focal length of the first lens610; f2 is a focal length of the second lens620.

The optical image capturing system of the sixth preferred embodiment further satisfies TP2=0.338 mm and TP3=0.646 mm, where TP2 is a thickness of the second lens620on the optical axis, and TP3 is a thickness of the third lens630on the optical axis.

In the sixth preferred embodiment, the first and the third lenses610,630are positive lenses, and their focal lengths are f1 and f3 respectively. The optical image capturing system of the sixth preferred embodiment further satisfies ΣPP=f1+f3=4.0907 mm and f1/(f1+f3)=0.4377, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens610to the other positive lens to avoid the significant aberration caused by the incident rays.

The optical image capturing system of the sixth preferred embodiment further satisfies ΣNP=f2, where ΣNP is a sum of the focal lengths of each negative lens.

The parameters of the lenses of the sixth preferred embodiment are listed in Table 11 and Table 12.

An equation of the aspheric surfaces of the sixth preferred embodiment is the same as that of the first preferred embodiment, and the definitions are the same as well.

The exact parameters of the sixth preferred embodiment (with 555 nm as the main reference wavelength) based on Table 11 and Table 12 are listed in the following table:

The exact parameters related to inflection points of the sixth preferred embodiment (with main reference wavelength as 555 nm) based on Table 11 and Table 12 are listed in the following table: