# Patent

## Title
Optical image capturing system

## Abstract

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 imaging quality for use in a compact camera.

## Background
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, there is an increasing demand for an optical image capturing system. 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 rising.
The conventional optical system of the portable electronic device usually has a two-piece lens. However, to take pictures in a dark environment, the optical system needs a large aperture. An optical system with large aperture typically has several problems, such as, large aberration, poor image quality at periphery of the image, and is burdensome to manufacture. In addition, a wide-angle optical system usually has large distortion. Therefore, conventional optical system do not provide high optical performance in these environments.
There is a need to increase the quantity of light entering the lens and the angle of field of the lens. In addition, the modern lens also needs improved properties, including high pixels, high image quality, a small size, and high optical performance.
BRIEF SUMMARY OF THE INVENTION
The aspect of 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 terms' definitions relate to the lens parameter in the embodiment of the present invention are provided below for further reference.
The lens parameter is 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 I321 which is nearest to the optical axis, and the sinkage value of the inflection point IF321 is denoted by SGI321 (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 SGI312 (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 SGI322 (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 imaging 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 0.5≦HOS/f≦3.0;

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)|≦3.0; 0.5≦HOS/f≦3.0; |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 at least one surface among an object-side surface and an image-side surface thereof 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)|≦3.0; 0.5≦HOS/f≦3.0; |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 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 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 embodiment, a height of the optical image capturing system (HOS) can be reduced while |f1|>f3.
In an 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 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.



BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which
FIG. 1A is a schematic diagram of a first preferred embodiment of the present invention;
FIG. 1B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the first embodiment of the present application;
FIG. 1C shows a curve diagram of TV distortion of the optical image capturing system of the first embodiment of the present application;
FIG. 2A is a schematic diagram of a second preferred embodiment of the present invention;
FIG. 2B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the second embodiment of the present application;
FIG. 2C shows a curve diagram of TV distortion of the optical image capturing system of the second embodiment of the present application;
FIG. 3A is a schematic diagram of a third preferred embodiment of the present invention;
FIG. 3B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the third embodiment of the present application;
FIG. 3C shows a curve diagram of TV distortion of the optical image capturing system of the third embodiment of the present application;
FIG. 4A is a schematic diagram of a fourth preferred embodiment of the present invention;
FIG. 4B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the fourth embodiment of the present application;
FIG. 4C shows a curve diagram of TV distortion of the optical image capturing system of the fourth embodiment of the present application;
FIG. 5A is a schematic diagram of a fifth preferred embodiment of the present invention;
FIG. 5B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the fifth embodiment of the present application;
FIG. 5C shows a curve diagram of TV distortion of the optical image capturing system of the fifth embodiment of the present application;
FIG. 6A is a schematic diagram of a sixth preferred embodiment of the present invention;
FIG. 6B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the sixth embodiment of the present application; and
FIG. 6C shows a curve diagram of TV distortion of the optical image capturing system of the sixth embodiment of the present application.



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 f 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 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 ETP 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 1≦(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 0.2≦(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 0.1≦(TP2/ΣTP≦0.3, where TP2 is a central thickness of the second lens on the optical axis, and ETP 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 0.1≦SGI312/(SGI312+TP3)≦0.8 and 0.1≦SGI322/(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 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+A88+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 embodiments in conjunction with the accompanying drawings for the best understanding, which are:
First Embodiment
As shown in FIG. 1A and FIG. 1B, an optical image capturing system 100 of the first preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens 110, an aperture 100, a second lens 120, a third lens 130, an infrared rays filter 170, an image plane 180, and an image sensor 190.
The first lens 110 has positive refractive power, and is made of plastic. An object-side surface 112 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 114 thereof, which faces the image side, is a concave aspheric surface.
The second lens 120 has negative refractive power, and is made of plastic. An object-side surface 122 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 124 thereof, which faces the image side, is a convex aspheric surface, and the image-side surface 124 has an inflection point. The second lens 120 satisfies 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 lens 130 has positive refractive power, and is made of plastic. An object-side surface 132, which faces the object side, is a convex aspheric surface, and an image-side surface 134, which faces the image side, is a concave aspheric surface. The object-side surface 132 has two inflection points, and the image-side surface 134 has an inflection point. The third lens 130 satisfies 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 lens 130 satisfies 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 lens 130 further 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 lens 130 further satisfies HIF312=0.8186 mm; HIF312/HOI=0.84568, 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 filter 170 is made of glass, and between the third lens 130 and the image plane 180. The infrared rays filter 170 gives 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 lens 110; and f3 is a focal length of the third lens 130.
The first preferred embodiment further satisfies f2=−5.2251 mm; and |f2|>|f1|, where f2 is a focal length of the second lens 120, and f3 is a focal length of the third lens 130.
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 f 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 surface 112 of the first lens 110 and the image-side surface 134 of the third lens 130; HOS is a height of the image capturing system, i.e., a distance between the object-side surface 112 of the first lens 110 and the image plane 180; InS is a distance between the aperture 100 and the image plane 180; 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 surface 134 of the third lens 130 and the image plane 180.
The optical image capturing system of the first preferred embodiment further satisfies ΣTP=1.4198 mm and ΣTP/InTL=0.6959, where ETP is a sum of the thicknesses of the lenses 110-130 with 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 surface 112 of the first lens 110, and R2 is a radius of curvature of the image-side surface 114 of the first lens 110. 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 surface 132 of the third lens 130, and R6 is a radius of curvature of the image-side surface 134 of the third lens 130. 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 lens 110 to 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 lens 120, 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 lens 110 and the second lens 120. 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 lens 110 on the optical axis, and TP2 is a central thickness of the second lens 120 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 first preferred embodiment further satisfies (TP3+IN23)/TP2=2.3308, where IN23 is a distance on the optical axis between the second lens 120 and the third lens 130. 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 lens 120, 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 surface 132 of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 132 of the third lens 130; InRS32 is a displacement in parallel with the optical axis from a point on the image-side surface 134 of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 134 of the third lens 130; and TP3 is a central thickness of the third lens 130 on 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 surface 132 of the third lens 130 and the optical axis is HVT31; a distance perpendicular to the optical axis between a critical point C32 on the image-side surface 134 of the third lens 130 and 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 lens 120 and the third lens 130 of the optical image capturing system of the first preferred embodiment have negative refractive power, and the optical image capturing system further satisfies |NA1−NA2|=33.595|; and NA3/NA2=2.4969, where NA1 is an Abbe number of the first lens 110, NA2 is an Abbe number of the second lens 120, and NA3 is an Abbe number of the third lens 130. 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 embodiment are listed in Table 1 and Table 2.







TABLE 1







f = 2.42952 mm; f/HEP = 2.02; HAF = 35.87 deg; tan(HAF) = 0.7231














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
600






1
1st lens
0.849
0.513
plastic
1.535
56.070
2.273


2

2.205
0.143


3
Aperture
plane
0.263


4
2nd lens
−1.208 
0.336
plastic
1.643
22.470
−5.225


5

−2.085 
0.214


6
3rd lens
1.178
0.570
plastic
1.544
56.090
7.012


7

1.411
0.114


8
Filter
plane
0.210
BK7_SCHOTT


9

plane
0.550


10
Image plane
plane
0.000





Reference wavelength: 555 nm; the clear aperture of the first surface is 0.640 mm.













TABLE 2







Coefficients of the aspheric surfaces













Surface
1
2
4
5
6
7





k =
1.22106E−01
1.45448E+01
8.53809E−01
4.48992E−01
−1.44104E+01
−3.61090E+00


A4 =
−6.43320E−04 
−9.87186E−02 
−7.81909E−01 
−1.69310E+00 
−7.90920E−01
−5.19895E−01


A6 =
−2.58026E−02 
2.63247E+00
−8.49939E−01 
5.85139E+00
 4.98290E−01
 4.24519E−01


A8 =
1.00186E+00
−5.88099E+01 
3.03407E+01
−1.67037E+01 
 2.93540E−01
−3.12444E−01


A10 =
−4.23805E+00 
5.75648E+02
−3.11976E+02 
2.77661E+01
−3.15288E−01
 1.42703E−01


A12 =
9.91922E+00
−3.00096E+03 
1.45641E+03
−5.46620E+00 
−9.66930E−02
−2.76209E−02


A14 =
−1.17917E+01 
7.91934E+03
−2.89774E+03 
−2.59816E+01 
 1.67006E−01
−3.11872E−03


A16 =
8.87410E+00
−8.51578E+03 
1.35594E+03
1.43091E+01
−4.43712E−02
 1.34499E−03


A18 =
0.00000E+00
0.00000E+00
0.00000E+00
0.00000E+00
 0.00000E+00
 0.00000E+00


A20 =
0.00000E+00
0.00000E+00
0.00000E+00
0.00000E+00
 0.00000E+00
 0.00000E+00









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 embodiments have the similar diagrams and tables, which are the same as those of the first embodiment, so we do not describe it again.
Second Embodiment
As shown in FIG. 2A and FIG. 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 lens 210, an aperture 200, a second lens 220, a third lens 230, an infrared rays filter 270, an image plane 280, and an image sensor 290.
The first lens 210 has positive refractive power, and is made of plastic. An object-side surface 212 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 214 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 212 has an inflection point thereon.
The second lens 220 has negative refractive power, and is made of plastic. An object-side surface 222 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 224 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 222 has two inflection points thereon, and the image-side surface 224 has an inflection point thereon.
The third lens 230 has positive refractive power, and is made of plastic. An object-side surface 232, which faces the object side, is a convex aspheric surface, and an image-side surface 234, which faces the image side, is a concave aspheric surface. The object-side surface 232 and the image-side surface both have an inflection point thereon.
The infrared rays filter 270 is made of glass, and between the third lens 230 and the image plane 280. The infrared rays filter 270 gives 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|=3.346 mm, |f1|=1.835 mm, and |f2|>|f1|, where f1 is a focal length of the first lens 210; f2 is a focal length of the second lens 220.
The optical image capturing system of the second preferred embodiment further satisfies TP2=0.348 mm and TP3=0.596 mm, where TP2 is a thickness of the second lens 220 on the optical axis, and TP3 is a thickness of the third lens 230 on the optical axis.
In the second embodiment, the first and the third lenses 210, 230 are 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=6.4494 mm and f1/(f1+f3)=0.2845, 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 lens 210 to 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 lens 220, and ΣNP is a sum of the focal lengths of each negative lens.
The parameters of the lenses of the second embodiment are listed in Table 3 and Table 4.







TABLE 3







f = 2.057 mm; f/HEP = 2.2; HAF = 40.555 deg; tan(HAF) = 0.8557














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
800






1
1st lens/aperture
 1.92122
0.512
plastic
1.535
56.070
1.835


2

 4.47502
0.257


3
2nd lens
plane
0.348
plastic
1.642
22.455
−3.346


4

−5.14086
0.225


5
3rd lens
−5.66431
0.596
plastic
1.535
56.070
4.614


6

−35.4311 
0.184


7
Filter
plane
0.210
BK7_SCHOTT
1.515
64.135


8

plane
0.485


9
Image plane
plane





Reference wavelength: 555 nm.













TABLE 4







Coefficients of the aspheric surfaces













Surface
1
2
3
4
5
6





k =
−8.543668E−01
−5.000000E+01
 8.361153E−01
−9.606588E+01
−9.566282E+00
−7.570904E−01


A4 =
−1.852370E−01
−6.743225E−01
−6.017233E−01
−3.943839E+00
−4.207809E−01
−7.299115E−01


A6 =
 6.648515E+00
−1.248606E+00
 4.925600E+00
 3.223536E+01
 3.728905E−01
 6.310904E−01


A8 =
−2.085146E+02
 3.963763E+01
−3.374586E+00
−2.143038E+02
 8.867358E−03
−1.196737E−01


A10 =
 3.454832E+03
−5.793885E+02
−1.793678E+02
 1.083792E+03
 1.812797E−01
−7.013291E−01


A12 =
−3.462627E+04
 4.669191E+03
 2.527606E+03
−3.769143E+03
−1.551975E+00
 1.125515E+00


A14 =
 2.134099E+05
−2.262385E+04
−1.516711E+04
 8.777716E+03
 2.576755E+00
−8.686918E−01


A16 =
−7.912456E+05
 6.583015E+04
 4.850963E+04
−1.303191E+04
−1.935997E+00
 3.745895E−01


A18 =
 1.618173E+06
−1.060853E+05
−8.162442E+04
 1.109631E+04
 7.046488E−01
−8.589537E−02


A20 =
−1.402923E+06
 7.247224E+04
 5.742924E+04
−4.116041E+03
−1.009718E−01
 8.140552E−03









An equation of the aspheric surfaces of the second embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the second embodiment (with 555 nm as the main reference wavelength) based on Table 3 and Table 4 are listed in the following table:

















InRS31
InRS32
HVT31
HVT32
|ODT|%
|TDT|%


0.07361
−0.00931
0.80107
1.01856
2.49952
0.66431


|f/f1|
|f/f2|
|f/f3|
|f1/f3|
|f1/f2|
|f2/f3|


1.12093
0.61474
0.44575
2.51472
1.82341
1.37913


ΣPPR
ΣNPR
EPPR/|ΣNPR|
(TP1 + IN12)/TP2
(TP3 + IN23)/TP2
TP2/ΣTP


1.56667
0.61474
2.54850
2.36163
2.36163
0.23891


ΣPP
ΣNP
f1/ΣPP
IN12/f




6.44941
−3.34590
0.28452
0.12504




HOS
InTL
HOS/HOI
InS/HOS
InTL/HOS
ΣTP/InTL


2.81613
1.93738
1.55159
0.97305
0.68796
0.75100


|InRS31|/TP3
|InRS32|/TP3
HVT32/HOI
HVT32/HOS




0.1236
0.0156
0.56119
0.36169











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



















HIF111
0.4160
HIF111/HOI
0.2292
SGI111
0.0642
|SGI111|/(|SGI111| + TP1)
0.1115


HIF211
0.4429
HIF211/HOI
0.2440
SGI211
−0.1277
|SGI211|/(|SGI211| + TP2)
0.2686


HIF212
0.5690
HIF212/HOI
0.3135
SGI212
−0.1911
|SGI212|/(|SGI212| + TP2)
0.3548


HIF221
0.4383
HIF221/HOI
0.2415
SGI221
−0.0815
|SGI221|/(|SGI221| + TP2)
0.1900


HIF311
0.3089
HIF311/HOI
0.1702
SGI311
0.0419
|SGI311|/(|SGI311| + TP3)
0.0658


HIF321
0.4394
HIF321/HOI
0.2421
SGI321
0.0759
|SGI321|/(|SGI321| + TP3)
0.1130









Third Embodiment
As shown in FIG. 3A and FIG. 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 lens 310, an aperture 300, a second lens 320, a third lens 330, an infrared rays filter 370, an image plane 380, and an image sensor 390.
The first lens 310 has positive refractive power, and is made of plastic. An object-side surface 312 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 314 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 312 has two inflection points thereon, and the image-side surface has an inflection point thereon.
The second lens 320 has negative refractive power, and is made of plastic. An object-side surface 322 thereof, which faces the object side, is a concave aspheric surface; while an image-side surface 324 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 322 and the image-side surface 324 both have an inflection point thereon.
The third lens 330 has positive refractive power, and is made of plastic. An object-side surface 332, which faces the object side, is a convex aspheric surface, and an image-side surface 334, which faces the image side, is a concave aspheric surface. The object-side surface 332 and the image-side surface have an inflection point thereon.
The infrared rays filter 370 is made of glass, and between the third lens 330 and the image plane 380. The infrared rays filter 370 gives no contribution to the focal length of the system.
The parameters of the lenses of the third preferred embodiment are |f2|=3.037 mm; |f1|=1.412 mm; and |f2|>|f1|, where f1 is a focal length of the first lens 310; f2 is a focal length of the second lens 320.
The optical image capturing system of the third preferred embodiment further satisfies TP2=0.311 mm and TP3=0.815 mm, where TP2 is a thickness of the second lens 320 on the optical axis, and TP3 is a thickness of the third lens 330 on the optical axis.
The optical image capturing system of the third preferred embodiment further satisfies ΣPP=f1+f3=10.86930 mm and f1/(f1+f3)=0.12995, 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 lens 310 to 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 embodiment are listed in Table 5 and Table 6.







TABLE 5







f = 1.980 mm; f/HEP = 2.2; HAF = 41.898 deg; tan(HAF) = 0.8972














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
600






1
Aperture
plane
−0.010


2
1st lens
1.691109
0.846
plastic
1.534598
56.070
1.412


3

−1.132732
0.278


4
2nd lens
−0.391595
0.311
plastic
1.642495
22.455
−3.037


5

−0.641741
0.030


6
3rd lens
1.406985
0.815
plastic
1.534598
56.070
9.457


7

1.553255
0.252


8
Filter
plane
0.210
BK7_SCHOTT
1.5146
64.135


9

plane
0.318


10
Image plane
plane





Reference wavelength: 555 nm.













TABLE 6







Coefficients of the aspheric surfaces













Surface
1
2
4
5
6
7





k =
−1.949115E+01
−2.320148E+00
−7.413095E−01 
−9.167540E−01
−2.841731E−01
−5.961438E+00


A4 =
 2.503769E−01
−5.273542E−01
1.655925E+00
 4.218113E−01
−6.113581E−01
−1.131550E−01


A6 =
−1.682460E−01
 9.285361E−01
−1.468505E+00 
−3.857547E−01
 3.316423E−01
 4.313548E−02


A8 =
−5.745426E+00
−7.689350E+00
7.090514E+00
 2.868973E+00
 1.295575E−01
−2.339485E−02


A10 =
 1.711465E+01
 2.199660E+01
5.324183E+00
−2.289240E+00
−3.944963E−01
−1.799633E−03


A12 =
 2.558724E+01
 1.216111E+01
−5.050230E+01 
−1.590342E+00
−1.036998E+00
 8.737996E−03


A14 =
−3.979505E+02
−1.451439E+02
5.272043E+01
−9.558163E−01
 2.553700E+00
−4.233080E−03


A16 =
 9.232178E+02
 1.634916E+02
1.465224E+01
 3.506766E+00
−1.540374E+00
 5.775537E−04









An equation of the aspheric surfaces of the third embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the third embodiment (with 555 nm as the main reference wavelength) based on Table 5 and Table 6 are listed in the following table:

















InRS31
InRS32
HVT31
HVT32
|ODT|%
|TDT|%


−0.01294
−0.02207
0.66345
1.02598
1.80039
0.41605


|f/f1|
|f/f2|
|f/f3|
|f1/f3|
|f1/f2|
|f2/f3|


1.40190
0.65197
0.20938
6.69535
2.15026
3.11374


ΣPPR
ΣNPR
ΣPPR/|ΣNPR|
(TP1 + IN12)/TP2
(TP3 + IN23)/TP2
TP2/ΣTP


1.61128
0.65197
2.47142
2.71454
2.71454
0.15787


ΣPP
ΣNP
f1/ΣPP
IN12/f




10.86930
−3.03714
0.12995
0.14047




HOS
InTL
HOS/HOI
InS/HOS
InTL/HOS
ΣTP/InTL


3.06079
2.28034
1.68639
0.99670
0.74502
0.86489


|InRS31|/TP3
|InRS32|/TP3
HVT32/HOI
HVT32/HOS




0.0159
0.0271
0.56528
0.33520











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



















HIF111
0.3968
HIF111/HOI
0.2186
SGI111
0.0419
|SGI111|/(|SGI111| + TP1)
0.0472


HIF112
0.4812
HIF112/HOI
0.2651
SGI112
0.0566
|SGI112|/(|SGI112| + TP1)
0.0628


HIF121
0.6652
HIF121/HOI
0.3665
SGI121
−0.2720
|SGI121|/(|SGI121| + TP1)
0.2434


HIF211
0.4516
HIF211/HOI
0.2488
SGI211
−0.2200
|SGI211|/(|SGI211| + TP2)
0.4140


HIF221
0.4685
HIF221/HOI
0.2581
SGI221
−0.1514
|SGI221|/(|SGI221| + TP2)
0.3271


HIF311
0.3546
HIF311/HOI
0.1954
SGI311
0.0362
|SGI311|/(|SGI311| + TP3)
0.0425


HIF321
0.5404
HIF321/HOI
0.2977
SGI321
0.0743
|SGI321|/(|SGI321| + TP3)
0.0835









Fourth Embodiment
As shown in FIG. 4A and FIG. 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 lens 410, an aperture 400, a second lens 420, a third lens 430, an infrared rays filter 470, an image plane 480, and an image sensor 490.
The first lens 410 has positive refractive power, and is made of plastic. An object-side surface 412 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 414 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 412 has an inflection point thereon.
The second lens 420 has negative refractive power, and is made of plastic. An object-side surface 422 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 424 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 422 and the image-side surface 424 both have an inflection point thereon.
The third lens 430 has positive refractive power, and is made of plastic. An object-side surface 432, which faces the object side, is a convex aspheric surface, and an image-side surface 434, which faces the image side, is a concave aspheric surface. The object-side surface 432 and the image-side surface both have two inflection points thereon.
The infrared rays filter 470 is made of glass, and between the third lens 430 and the image plane 480. The infrared rays filter 470 gives 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 lens 410; f2 is a focal length of the second lens 420.
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 lens 420 on the optical axis, and TP3 is a thickness of the third lens 430 on the optical axis.
In the fourth embodiment, the first and the third lenses 410, 430 are 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 lens 410 to 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 lens 420, and ΣNP is a sum of the focal lengths of each negative lens.
The parameters of the lenses of the fourth embodiment are listed in Table 7 and Table 8.







TABLE 7







f = 2.890 mm; f/HEP = 1.8; HAF = 37.761 deg; tan(HAF) = 0.7746














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
3000






1
Aperture
plane
0.025


2
1st lens
2.998988
0.893
plastic
1.544
56.09
2.450


3

−2.159869
0.682


4
2nd lens
−0.401292
0.215
plastic
1.642
22.46
−2.629


5

−0.635803
0.025


6
3rd lens
1.397267
1.444
plastic
1.544
56.09
3.254


7

4.156130
0.115


8
Filter
plane
0.200
BK7_SCHOTT
1.517
64.13


9

plane
0.700


10
Image plane
plane





Reference wavelength: 555 nm.


The clear aperture of the third surface is 1.060 mm













TABLE 8







Coefficients of the aspheric surfaces













Surface
2
3
4
5
6
7





k =
 1.362696E+00
−1.607824E+01
−1.779113E+00
−3.128736E+00
−1.005235E−01
−2.890826E+00


A4 =
−1.061802E−01
−3.186043E−01
 7.275449E−01
−2.388256E−01
−6.439017E−01
−7.999813E−02


A6 =
 1.443026E−01
 3.892705E−01
−2.157641E+00
 2.301212E+00
 1.331801E+00
 9.268036E−03


A8 =
−1.855754E+00
−1.650198E+00
 6.151816E+00
−8.689047E+00
−2.924987E+00
 5.818126E−02


A10 =
 1.030755E+01
 6.535161E+00
−9.764070E+00
 2.353544E+01
 4.925219E+00
−7.513945E−02


A12 =
−3.800603E+01
−1.658255E+01
 8.106311E+00
−4.084789E+01
−5.939244E+00
 4.408450E−02


A14 =
 8.939147E+01
 2.569899E+01
−2.403390E+00
 4.443919E+01
 4.868202E+00
−1.422997E−02


A16 =
−1.287995E+02
−2.370893E+01
−1.223613E+00
−2.949477E+01
−2.564171E+00
 2.510706E−03


A18 =
 1.029344E+02
 1.195833E+01
 1.147289E+00
 1.095734E+01
 7.802818E−01
−2.131331E−04


A20 =
−3.486733E+01
−2.541992E+00
−2.557074E−01
−1.749401E+00
−1.043312E−01
 5.517283E−06









An equation of the aspheric surfaces of the fourth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the fourth embodiment (with 555 nm as the main reference wavelength) based on Table 7 and Table 8 are listed in the following table:

















InRS31
InRS32
HVT31
HVT32
|ODT|%
|TDT|%


0.08248
−0.37336
1.06345
1.15309
1.50942
0.87655


|f/f1|
|f/f2|
|f/f3|
|f1/f3|
|f1/f2|
|f2/f3|


1.17960
1.09942
0.88798
1.32840
1.07292
1.23811


ΣPPR
ΣNPR
ΣPPR/|ΣNPR|
(TP1 + IN12)/TP2
(TP3 + IN23)/TP2
TP2/ΣTP


2.06758
1.09942
1.88061
6.82402
6.82402
0.08435


ΣPP
ΣNP
f1/ΣPP
IN12/f




5.70439
−2.62858
0.42948
0.23610




HOS
InTL
HOS/HOI
InS/HOS
InTL/HOS
ΣTP/InTL


4.27500
3.26002
1.88492
0.98888
0.76258
0.78303


|InRS31|/TP3
|InRS32|/TP3
HVT32/HOI
HVT32/HOS




0.0571
0.2585
0.50842
0.26973











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



















HIF111
0.47168
HIF111/HOI
0.20797
SGI111
0.03221
|SGI111|/(|SGI111| + TP1)
0.03481


HIF211
0.46060
HIF211/HOI
0.20309
SGI211
−0.19705
|SGI211|/(|SGI211| + TP2)
0.47785


HIF221
0.47369
HIF221/HOI
0.20886
SGI221
−0.14125
|SGI221|/(|SGI221| + TP2)
0.39614


HIF311
0.51240
HIF311/HOI
0.22593
SGI311
0.06736
|SGI311|/(|SGI311| + TP3)
0.04456


HIF321
0.57077
HIF321/HOI
0.25166
SGI321
0.03111
|SGI321|/(|SGI321| + TP3)
0.02108









Fifth Embodiment
As shown in FIG. 5A and FIG. 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 aperture 500, a first lens 510, a second lens 520, a third lens 530, an infrared rays filter 570, an image plane 580, and an image sensor 590.
The first lens 510 has positive refractive power, and is made of plastic. An object-side surface 512 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 514 thereof, which faces the image side, is a concave aspheric surface.
The second lens 520 has positive refractive power, and is made of plastic. An object-side surface 522 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 524 thereof, which faces the image side, is a convex aspheric surface. The image-side surface 524 has two inflection points.
The third lens 530 has negative refractive power, and is made of plastic. An object-side surface 532, which faces the object side, is a convex aspheric surface, and an image-side surface 534, which faces the image side, is a concave aspheric surface. The object-side surface has three inflection points thereon, and the image-side surface 534 has an inflection point.
The infrared rays filter 570 is made of glass, and between the third lens 530 and the image plane 580. The infrared rays filter 570 gives 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 lens 510; f2 is a focal length of the second lens 520.
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 lens 520 on the optical axis, and TP3 is a thickness of the third lens 530 on the optical axis.
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 lens 510 to 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 embodiment are listed in Table 9 and Table 10.







TABLE 9







f = 1.340 mm; f/HEP = 2.46; HAF = 38.834 deg; tan(HAF) = 0.8050














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
600






1

plane
0.102


2
Aperture
plane
−0.08312


3
1st lens
0.49281
0.29050
plastic
1.535
56.05
1.452


4

1.06545
0.21304


5
2nd lens
−0.96594
0.24240
plastic
1.535
56.05
1.387


6

−0.45709
0.03527


7
3rd lens
16.05009
0.29395
plastic
1.535
56.05
−1.254


8

0.64146
0.10900


9
Filter
plane
0.21


10

plane
0.237


11
Image plane
plane
0





Reference wavelength: 555 nm













TABLE 10







Coefficients of the aspheric surfaces













Surface
3
4
5
6
7
8





k =
2.01824E−02
9.55965E+00
−4.41020E+01
−1.23809E+01
−1.53530E+04
−6.45641E+00


A4 =
2.73779E−01
9.36063E−01
−3.97557E+00
−9.99887E+00
−2.47339E+00
−2.76537E+00


A6 =
−1.74068E+01 
6.83878E+00
 2.79159E+01
 1.81093E+02
 1.54556E+01
 1.48443E+01


A8 =
1.22816E+03
−9.31427E+02 
 1.39349E+03
−2.00026E+03
−5.09297E+01
−6.18536E+01


A10 =
−3.35987E+04 
3.32362E+04
−5.27979E+04
 1.50954E+04
 1.29379E+02
 1.67430E+02


A12 =
4.95528E+05
−5.79704E+05 
 7.72144E+05
−7.06870E+04
−2.55156E+02
−2.67187E+02


A14 =
−3.90842E+06 
4.95867E+06
−5.01063E+06
 1.84693E+05
 2.71245E+02
 1.81948E+02


A16 =
1.30544E+07
−1.63270E+07 
 3.64087E+06
−2.22351E+05
−6.02299E+01
 9.99102E+01


A18 =
0.00000E+00
0.00000E+00
 1.14092E+08
 3.64341E+04
−6.24963E+01
−2.46729E+02


A20 =
0.00000E+00
0.00000E+00
−4.19185E+08
 8.63213E+04
−2.79496E+00
 1.15666E+02









An equation of the aspheric surfaces of the fifth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the fifth embodiment (with 555 nm as the main reference wavelength) based on Table 9 and Table 10 are listed in the following table:

















InRS31
InRS32
HVT31
HVT32
|ODT|%
|TDT|%


−0.03679
−0.04875
0.07573
0.45922
0.81360
0.57628


|f/f1|
|f/f2|
|f/f3|
|f1/f3|
|f1/f2|
|f2/f3|


0.92259
0.96600
1.06842
0.86351
0.95506
0.90414


ΣPPR
ΣNPR
ΣPPR/|ΣNPR|
(TP1 + IN12)/TP2
(TP3 + IN23)/TP2
TP2/ΣTP


1.88859
1.06842
1.76764
1.35819
1.35819
0.29316


ΣPP
ΣNP
f1/ΣPP
IN12/f




2.83947
−1.2541
0.51149
0.15899




HOS
InTL
HOS/HOI
InS/HOS
InTL/HOS
ΣTP/InTL


1.63116
1.07516
1.50754
0.94904
0.65914
0.76905


|InRS31|/TP3
|InRS32|/TP3
HVT32/HOI
HVT32/HOS




0.12516
0.16586
0.42441
0.28153











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



















HIF221
0.261825
HIF221/HOI
0.241982
SGI221
−0.0633236
|SGI221|/(|SGI221| + TP2)
0.20713


HIF222
0.415454
HIF222/HOI
0.383969
SGI222
−0.113198
|SGI222|/(|SGI222| + TP2)
0.318336


HIF311
0.04297
HIF311/HOI
0.039713
SGI311
0.000048
|SGI311|/(|SGI311| + TP3)
0.000163


HIF312
0.358423
HIF312/HOI
0.33126
SGI312
−0.0163614
|SGI312|/(|SGI312| + TP3)
0.052725


HIF313
0.538607
HIF313/HOI
0.497788
SGI313
−0.0314042
|SGI313|/(|SGI313| + TP3)
0.096522


HIF321
0.202546
HIF321/HOI
0.187196
SGI321
0.0247325
|SGI321|/(|SGI321| + TP3)
0.077608









Sixth Embodiment
As shown in FIG. 6A and FIG. 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 aperture 600, a first lens 610, a second lens 620, a third lens 630, an infrared rays filter 670, an image plane 680, and an image sensor 690.
The first lens 610 has positive refractive power, and is made of plastic. An object-side surface 612 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 614 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 612 has an inflection point thereon.
The second lens 620 has negative refractive power, and is made of plastic. An object-side surface 622 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 624 thereof, which faces the image side, is a convex aspheric surface. The object-side surface 622 and the image-side surface 624 both have an inflection point thereon.
The third lens 630 has positive refractive power, and is made of plastic. An object-side surface 632, which faces the object side, is a convex aspheric surface, and an image-side surface 634, which faces the image side, is a concave aspheric surface. The object-side surface 632 and the image-side surface 634 both have an inflection point thereon.
The infrared rays filter 670 is made of glass, and between the third lens 630 and the image plane 680. The infrared rays filter 670 gives 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 lens 610; f2 is a focal length of the second lens 620.
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 lens 620 on the optical axis, and TP3 is a thickness of the third lens 630 on the optical axis.
The optical image capturing system of the sixth preferred embodiment further satisfies ΣPP=f1+f2=4.0907 mm and f1/(f1+f2)=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 lens 610 to 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 embodiment are listed in Table 11 and Table 12.







TABLE 10







f = 2.334 mm; f/HEP = 1.8; HAF = 43.934 deg; tan(HAF) = 0.9635














Radius of curvature
Thickness

Refractive
Abbe
Focal length


Surface
(mm)
(mm)
Material
index
number
(mm)

















0
Object
plane
6000






1
Aperture
plane
0.245


2
1st lens
2.273980
1.187
plastic
1.544
56.09
1.791


3

−1.398300
0.234


4
2nd lens
−0.424004
0.338
plastic
1.642
22.46
−1.706


5

−0.903506
0.025


6
3rd lens
0.863493
0.646
plastic
1.642
22.46
2.300


7

1.450258
0.326


8
Filter
plane
0.300

1.517
64.13


9

plane
0.700


10
Image plane
plane





Reference wavelength: 555 nm.


The clear aperture of the third surface is 0.980 mm













TABLE 11







Coefficients of the aspheric surfaces













Surface
2
3
4
5
6
7





k =
−5.793298E+01 
−1.047222E+01
−2.214799E+00
−1.609407E+00 
−1.279016E+00
−5.974452E+00


A4 =
5.680888E−01
−3.906179E−01
 7.450205E−01
3.279455E−01
−7.661874E−01
 7.677749E−02


A6 =
−2.795876E+00 
−2.002429E−01
−6.574821E+00
−8.799316E−01 
 1.625831E+00
−1.684057E−01


A8 =
1.063340E+01
−6.185052E−01
 2.106066E+01
4.139075E−01
−2.860513E+00
 1.039362E−01


A10 =
−2.849055E+01 
 4.623426E+00
−3.528569E+01
3.660140E+00
 3.247167E+00
−1.815849E−02


A12 =
4.688333E+01
−7.602169E+00
 3.509519E+01
−8.188023E+00 
−2.233218E+00
−1.486964E−02


A14 =
−4.319063E+01 
 5.161391E+00
−2.125517E+01
7.720120E+00
 8.403317E−01
 9.981753E−03


A16 =
1.663827E+01
−1.295352E+00
 7.457267E+00
−3.562241E+00 
−1.320160E−01
−2.377427E−03


A18 =
0.000000E+00
 0.000000E+00
−1.193774E+00
6.639228E−01
−6.379427E−04
 2.051198E−04


A20 =









An equation of the aspheric surfaces of the sixth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the sixth embodiment (with 555 nm as the main reference wavelength) based on Table 11 and Table 12 are listed in the following table:

















InRS31
InRS32
HVT31
HVT32
|ODT|%
|TDT|%


0.17395
0.14969
1.06733
1.32084
1.08812
0.25449


|f/f1|
|f/f2|
|f/f3|
|f1/f3|
|f1/f2|
|f2/f3|


1.30350
1.36818
1.01473
1.28457
0.95272
1.34831


ΣPPR
ΣNPR
ΣPPR/|ΣNPR|
(TP1 + IN12)/TP2 
(TP3 + IN23)/TP2
TP2/ΣTP


2.31823
1.36818
1.69439
1.98672
1.98672
0.15560


ΣPP
ΣNP
f1/ΣPP
IN12/f




4.09066
−1.70591
0.43772
0.10018




HOS
InTL
HOS/HOI
InS/HOS
InTL/HOS
ΣTP/InTL


3.75481
2.42939
1.65556
1.06530
0.64701
0.89346


|InRS31|/TP3
|InRS32|/TP3
HVT32/HOI
HVT32/HOS




0.2693
0.2317
0.58238
0.35177











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



















HIF111
0.5566
HIF111/HOI
0.2454
SGI111
0.0630
|SGI111|/(|SGI111| + TP1)
0.0504


HIF211
0.6152
HIF211/HOI
0.2713
SGI211
−0.3185
|SGI211|/(|SGI211| + TP2)
0.4853


HIF221
0.6419
HIF221/HOI
0.2830
SGI221
−0.1904
|SGI221|/(|SGI221| + TP2)
0.3606


HIF311
0.5698
HIF311/HOI
0.2512
SGI311
0.1351
|SGI311|/(|SGI311| + TP3)
0.1730


HIF321
0.7070
HIF321/HOI
0.3117
SGI321
0.1430
|SGI321|/(|SGI321| + TP3)
0.1813









It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.

## Claims

1. An optical image capturing system, in order along an optical axis from an object side to an image side, comprising:
a first lens having positive refractive power;
a second lens having refractive power;
a third lens having refractive power; and
an image plane;
an aperture and an image sensor on the image plane,
wherein the optical image capturing system consists of the three lenses with refractive power;
at least two of the three lenses each has at least an inflection point on at least a surface thereof;
the third lens has an object-side surface, which faces the object side, and an image-side surface, which faces the image side, and
both the object-side surface and the image-side surface of the third lens are aspheric surfaces;
wherein the optical image capturing system satisfies:


1.2≦f/HEP≦6.0; and



0.5≦HOS/f≦3.0; and



0.5≦InS/HOS≦1.1; and



0<HIF/HOI≦0.9;


where f1, f2, and f3 are focal lengths of the first lens to the third lens, respectively;
f is a focal length of the optical image capturing system;
where InS is a distance in parallel with the optical axis between the aperture and the image plane; and
HIF is a distance perpendicular to the optical axis between any inflection point and the optical axis,
HOI is a height for an image formation 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 from an object-side surface of the first lens to the image plane.

2. The optical image capturing system of claim 1, wherein the optical image capturing system further satisfies:


0 deg<HAF≦70 deg;



|TDT|<60%; and



|ODT|<50%;

where HAF is a half of a view angle of the optical image capturing system; TDT is a TV distortion; and ODT is an optical distortion.

3. The optical image capturing system of claim 1, wherein the third lens has at least an inflection point on at least one of the surfaces thereof.

4. The optical image capturing system of claim 1, wherein the optical image capturing system further satisfies:


0 mm<HIF≦5 mm.

5. The optical image capturing system of claim 4, wherein the optical image capturing system further satisfies:


0<HIF/InTL≦5;

where InTL is a distance in parallel with the optical axis between the object-side surface of the first lens and the image-side surface of the third lens.

6. The optical image capturing system of claim 4, wherein the optical image capturing system further satisfies:


0 mm<SGI≦1 mm;

where PI is a point on a surface of the lenses, through which the optical axis passes, and SGI is a displacement in parallel with the optical axis from PI to the inflection point on the surface.

7. The optical image capturing system of claim 1, wherein the third lens has positive refractive power.

8. The optical image capturing system of claim 1, wherein the optical image capturing system further satisfies:


0.5≦InTL/HOS≦0.9;

where InTL is a distance in parallel with the optical axis between the object-side surface of the first lens and the image-side surface of the third lens.