CN213986993U

CN213986993U - Imaging optical system, image capturing module and electronic device

Info

Publication number: CN213986993U
Application number: CN202023333322.8U
Authority: CN
Inventors: 谢晗; 李明; 邹海荣
Original assignee: Jiangxi Jingchao Optical Co Ltd
Current assignee: Jiangxi Jingchao Optical Co Ltd
Priority date: 2020-12-31
Filing date: 2020-12-31
Publication date: 2021-08-17
Anticipated expiration: 2030-12-31

Abstract

The utility model discloses an imaging optical system, get for instance module and electron device. The imaging optical system includes, in order from an object side to an image side along an optical axis, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens having power. The imaging optical system satisfies the conditional expression: HFOV >25 degrees, f/TTL > 1; the HFOV is a half of a maximum field angle of the imaging optical system, f is an effective focal length of the imaging optical system, and TTL is a distance on an optical axis from an object-side surface of the first lens element to the imaging surface. The utility model discloses embodiment's formation of image optical system can obtain long burnt, the good camera lens of formation of image quality.

Description

Imaging optical system, image capturing module and electronic device

Technical Field

The utility model relates to an optical imaging technique, in particular to imaging optical system, get for instance module and electron device.

Background

In recent years, the demand of consumers for electronic products such as smart phones has been increasing, and the imaging lenses mounted thereon have also been diversified, and especially, concepts such as double-camera and triple-camera modules have been proposed in the recent imaging function, and optical lenses have higher specifications such as large aperture + wide angle, long focus + large image plane, and on the basis of the above, the optical lenses also have good resolution, and the difficulty of optical design has been increasing dramatically.

SUMMERY OF THE UTILITY MODEL

The utility model discloses embodiment provides an imaging optical system, get for instance module and electron device.

The utility model discloses embodiment's optical system that forms images, optical system that forms images includes from the thing side to the image side along the optical axis in proper order: a first lens having an optical power; a second lens having an optical power; a third lens having optical power; a fourth lens having an optical power; a fifth lens having optical power; a sixth lens having optical power; the imaging optical system satisfies the conditional expression: HFOV >25 degrees, f/TTL > 1; the HFOV is a half of a maximum field angle of the imaging optical system, f is an effective focal length of the imaging optical system, and TTL is a distance from an object side surface of the first lens to the imaging surface on an optical axis.

The utility model discloses embodiment's imaging optical system, six formula optical structure can guarantee higher analytic power. The maximum field angle of the imaging optical system is enlarged by limiting the HFOV to be more than 25 degrees, and the effective focal length f of the imaging optical system is controlled to be larger than the distance TTL on the optical axis from the object side surface of the first lens to the imaging surface, so that the imaging optical system can obtain a long-focus lens with good imaging quality.

In some embodiments, the first lens has a positive optical power, the object side surface of the first lens being convex at the paraxial region; the second lens has a negative optical power; the fifth lens has a negative optical power, and an object side surface of the fifth lens is concave at a paraxial region. Therefore, the focal power of the lens can be reasonably distributed, light rays are in smooth transition, and the long-focus characteristic of the optical system is realized.

In some embodiments, the imaging optical system satisfies the following conditional expression: 0< T56/CT6< 0.93; wherein T56 is the air space between the fifth lens and the sixth lens on the optical axis, and CT6 is the central thickness of the sixth lens on the optical axis. Therefore, under the characteristic of a long-focus structure, the total length of the imaging optical system is compressed, the surface shapes of the two lenses can be closer, and the sensitivity of system performance change is reduced. The sixth lens is beneficial to forming processing while ensuring the thickness of the lens and is matched with the fifth lens to correct edge aberration and distortion, so that the resolution can be improved.

In some embodiments, an object-side surface of the sixth lens element is convex at a paraxial region and an image-side surface of the sixth lens element is concave at a paraxial region, and at least one of the object-side surface and the image-side surface of the sixth lens element has an inflection point. Thereby, it is possible to facilitate the miniaturized design of the imaging optical system.

In some embodiments, the imaging optical system satisfies the following conditional expression: 0< | f5/f6| < 2.6; wherein f5 is the focal length of the fifth lens, and f6 is the focal length of the sixth lens. Therefore, the imaging optical system has the characteristics of large magnification and small depth of field. If the refractive power exceeds the upper limit, the positive refractive power of the sixth lens is too large, and it is difficult to sufficiently correct chromatic aberration.

In certain embodiments, the imaging optical system satisfies the following conditional expression: 0.46< ImgH/f < 0.52; wherein ImgH is half of the image height corresponding to the maximum field angle of the imaging optical system. Therefore, the focal length is increased, and the characteristics of large imaging magnification and small depth of field of the imaging optical system are achieved.

In certain embodiments, the imaging optical system satisfies the following conditional expression: -0.1< f2/f34< 0.1; wherein f2 is the focal length of the second lens, and f34 is the combined focal length of the third lens and the fourth lens. Therefore, the third lens and the fourth lens can share weak focal power to be matched with the second lens to correct spherical aberration, and the resolution is improved. If the power is higher than the upper limit of the expression, the negative focal power provided by the three-four lenses together is too large, the high-order aberration is increased, and the resolution is reduced.

In certain embodiments, the imaging optical system satisfies the following conditional expression: -3.33< (R51+ R52)/(R51-R52) < 0; wherein R51 is a radius of curvature at the optical axis of the object-side surface of the fifth lens, and R52 is a radius of curvature at the optical axis of the image-side surface of the fifth lens. Therefore, when the principal ray is incident on the surface of the lens, the incident angle is small, the curvature radius of the fifth lens is reasonably optimized, the focal power of the fifth lens is restrained within a certain range, and meridional astigmatism and off-axis coma can be conveniently corrected.

In certain embodiments, the imaging optical system satisfies the following conditional expression: -5.5< f5/f < -1; wherein f5 is the focal length of the fifth lens. Therefore, the distortion and aberration of the imaging optical system can be effectively corrected, and good imaging quality is ensured. If the negative focal power of the fifth lens is higher than the upper limit of the expression, the high-order aberration is increased, and if the negative focal power of the fifth lens is lower than the lower limit of the expression, the negative focal power of the fifth lens is smaller, and the aberration correction is insufficient.

Optionally, the imaging optical system satisfies the following conditional expression: -18.6< SAG51/SAG61< 7.4; SAG51 is the axial distance from the intersection point of the object side surface of the fifth lens and the optical axis to the projection of the optically effective area edge of the object side surface of the fifth lens on the optical axis, and SAG61 is the axial distance from the intersection point of the object side surface of the sixth lens and the optical axis to the projection of the optically effective area edge of the object side surface of the sixth lens on the optical axis. Therefore, the fifth lens and the sixth lens keep the same-direction curvatures, and assembly production is facilitated, wherein the fifth lens is obvious in bending amplitude and large in rise absolute value, so that distortion of a marginal field of view is corrected, excessive increase of optical distortion is restrained, and the two lenses are matched more closely by controlling the proportion of SAG51/SAG61, and the resolving power is improved.

In some embodiments, the imaging optical system further includes: a stop disposed in the middle between an image-side surface of the second lens and an object-side surface of the third lens. From this, can control the light quantity better, promote the whole luminance of formation of image, guarantee that the imaging surface satisfies great receipts light area, promote the formation of image effect. The diaphragm is arranged in the middle, so that the eccentric inclination sensitivity of the system is reduced, and the production yield can be effectively improved. In the telephoto lens, the aperture of the diaphragm is reduced.

The utility model discloses get for instance the module includes above-mentioned arbitrary embodiment imaging optical system and electronic photosensitive element. The electronic photosensitive element is arranged on the image side of the imaging optical system.

The utility model discloses embodiment gets for instance module has long burnt, the good characteristics of formation of image quality.

The utility model discloses embodiment's electronic device includes casing and above-mentioned embodiment get for instance the module. The image capturing module is installed on the shell. The utility model discloses embodiment's electron device can obtain long burnt, the good camera lens of formation of image quality through reasonable lens configuration.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of an imaging optical system according to a first embodiment of the present invention;

fig. 2 to 4 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion graph (%), respectively, of the imaging optical system in the first embodiment;

fig. 5 is a schematic structural view of an imaging optical system according to a second embodiment of the present invention;

fig. 6 to 8 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%), respectively, of the imaging optical system in the second embodiment;

fig. 9 is a schematic structural view of an imaging optical system according to a third embodiment of the present invention;

fig. 10 to 12 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%), respectively, of the imaging optical system in the third embodiment;

fig. 13 is a schematic structural view of an imaging optical system according to a fourth embodiment of the present invention;

fig. 14 to 16 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%), respectively, of the imaging optical system in the fourth embodiment;

fig. 17 is a schematic structural view of an imaging optical system according to a fifth embodiment of the present invention;

fig. 18 to 20 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%), respectively, of the imaging optical system in the fifth embodiment;

fig. 21 is a schematic structural view of an imaging optical system according to a sixth embodiment of the present invention;

fig. 22 to 24 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%), respectively, of the imaging optical system in the sixth embodiment;

fig. 25 is a schematic structural view of an imaging optical system according to a seventh embodiment of the present invention;

fig. 26 to 28 are a longitudinal spherical aberration diagram (mm), an astigmatism diagram (mm), and a distortion curve diagram (%) of the imaging optical system in the seventh embodiment, respectively.

Reference numerals:

the imaging optical system 10, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the stop STO, the infrared filter 9, the object-side surface S1 of the first lens, the image-side surface F1 of the first lens, the object-side surface S2 of the second lens, the image-side surface F2 of the second lens, the object-side surface S3 of the third lens, the image-side surface F3 of the third lens, the object-side surface S4 of the fourth lens, the image-side surface F4 of the fourth lens, the object-side surface S5 of the fifth lens, the image-side surface F5 of the fifth lens, the object-side surface S6 of the sixth lens, the image-side surface F6 of the sixth lens, the object-side surface S7 of the seventh lens, the image-side surface F7 of the seventh lens, and the optical axis OO'.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "center", "length", "width", "thickness", "axial", "radial", "circumferential", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. In order to simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of simplicity and clarity and do not in themselves dictate a relationship between the various embodiments and/or arrangements discussed. In addition, the present disclosure provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

Referring to fig. 1, 5, 9, 13, 17, 21, and 25, the imaging optical system 10 according to the embodiment of the present invention includes, in order from an object side to an image side along an optical axis OO', a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, and a sixth lens 6 having optical power. When the imaging optical system 10 is used for imaging, light emitted or reflected by a subject enters the imaging optical system 10 from the object side direction, sequentially passes through the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5 and the sixth lens 6, and is converged on an imaging surface for imaging.

The imaging optical system 10 satisfies the conditional expression: HFOV >25 degrees; the HFOV is one half of the maximum field angle of the imaging optical system 10. That is, the maximum angle of view of the imaging optical system 10 is larger than 50 degrees. Alternatively, the HFOV value may be selected to be 25.1 degrees, 26 degrees, 26.1 degrees, 27 degrees, 27.2 degrees, etc.

The HFOV is defined here to be >25 degrees, and the imaging optical system 10 is used for a telephoto lens, and the focal length is long. When the telephoto lens uses the chip with the same size, the maximum field angle of the application can be enlarged to more than 50 degrees, so that the lens has the telephoto characteristic, and the image range is enlarged. The imaging optical system 10 satisfies the conditional expression: f/TTL >1, where f is an effective focal length of the imaging optical system 10, and TTL is a distance on the optical axis OO' from the object-side surface S1 of the first lens element 1 to the imaging surface. That is, f divided by TTL is greater than 1, i.e., f is greater than TTL. Alternatively, the f/TTL value can be 1, 1.5, 2, 2.5, 3, 3.5, 4, etc. Thus, the imaging optical system 10 can control the effective focal length of the optical imaging system 10 to be larger than the distance from the object side surface S1 of the first lens 1 to the imaging surface on the optical axis OO', so that the imaging optical system 10 has the characteristics of large magnification and small depth of field.

The imaging optical system 10 of the present application is a telephoto imaging lens, which has characteristics of large magnification, small depth of field, and the like, and is beneficial to blurring an image background, and has a better shooting effect and a larger market attention.

The utility model discloses embodiment's imaging optical system 10, six formula optical structures can guarantee higher analytic power. By limiting HFOV >25 degrees, the maximum field angle of the imaging optical system 10 is enlarged, and by controlling the effective focal length f of the optical imaging system 10 to be larger than the distance TTL on the optical axis OO' from the object side surface S1 of the first lens 1 to the imaging surface, the imaging optical system 10 can obtain a long-focus lens with good imaging quality.

In some embodiments, the first lens 1 has positive optical power, the object side surface S1 of the first lens 1 being convex at the paraxial region OO'; the second lens 2 has negative focal power; the fifth lens element 5 has a negative power, and the object-side surface S5 of the fifth lens element 5 is concave at the paraxial region OO'. Therefore, the focal power of the lens can be reasonably distributed, light rays are in smooth transition, and the long-focus characteristic of the optical system is realized.

In some embodiments, the imaging optical system 10 satisfies the following conditional expression: 0< T56/CT6< 0.93; t56 is the air space between the fifth lens element 5 and the sixth lens element 6 on the optical axis OO ', and CT6 is the center thickness of the sixth lens element 6 on the optical axis OO'. Therefore, the air gap between the fifth lens 5 and the sixth lens 6 can be reasonably optimized, so that the gap between the two lenses is not excessively increased, the total length of the imaging optical system 10 is compressed under the characteristic of a long-focus structure, the surface shapes of the two lenses can be closer, and the sensitivity of system performance change is reduced. The sixth lens 6 is matched with the fifth lens 5 to correct edge aberration and distortion while ensuring the thickness of the lens and being beneficial to forming processing, and the resolution can be improved.

In some embodiments, the object-side surface S6 of the sixth lens element 6 is convex at the paraxial region OO ', the image-side surface F6 of the sixth lens element 6 is concave at the paraxial region OO', and at least one of the object-side surface S6 and the image-side surface F6 of the sixth lens element 6 has an inflection point. Thereby, a miniaturized design of the imaging optical system 10 can be facilitated.

In some embodiments, the imaging optical system 10 satisfies the following conditional expression: 0< | f5/f6| < 2.6; where f5 is the focal length of the fifth lens 5, and f6 is the focal length of the sixth lens 6. That is, -2.6< f5/f6<0, or 0< f5/f6< 2.6. That is, the absolute value of the result of dividing f5 by f6 is an arbitrary value in the interval (0,2.6), and for example, the value may be 0.1, 0.2, 0.5, 1, 1.7, 2, 2.5, or the like.

Specifically, the fifth lens 5 provides a small negative power, and the sixth lens 6 provides a weak positive or negative power to cooperate with the fifth lens 5 to realize a telephoto characteristic, so that the imaging optical system 10 has characteristics of a large magnification and a small depth of field. If the refractive power exceeds the upper limit, the positive power of the sixth lens 6 becomes too large, and it becomes difficult to sufficiently correct chromatic aberration.

Alternatively, f5/f6 ranges from: f5/f6>1.66 or-0.203 < f5/f6< 0.

In certain embodiments, the imaging optical system 10 satisfies the following conditional expressions: 0.46< ImgH/f < 0.52; here, ImgH is half the image height corresponding to the maximum field angle of the imaging optical system 10. That is, the division of ImgH by f may be any value within the interval (0.46,0.52), for example, the value may be 0.47, 0.48, 0.49, 0.5, 0.51, or the like. With this arrangement, the focal length can be increased in the case of the sensor size characteristic, and the characteristics of the imaging optical system 10, such as a large imaging magnification and a small depth of field, can be achieved.

In certain embodiments, the imaging optical system 10 satisfies the following conditional expressions: -0.1< f2/f34< 0.1; where f2 is the focal length of the second lens 2, and f34 is the combined focal length of the third lens 3 and the fourth lens 4. That is, the division of f2 by f34 may be any number within the interval (-0.1,0.1), for example, the value may be-0.09, 0, 0.01, 0.05, 0.08, etc. Therefore, the third lens 3 and the fourth lens 4 can share weak focal power to match the second lens 2 to correct spherical aberration, and the resolution is improved. If the power is higher than the upper limit of the expression, the third lens 3 and the fourth lens 4 jointly provide too large negative power, the high-order aberration is increased, and the resolution is reduced, and if the power is lower than the lower limit of the expression, the power is larger, the total length of the system is reduced, and the long-focus characteristic of the lens is weakened.

In certain embodiments, the imaging optical system 10 satisfies the following conditional expressions: -3.33< (R51+ R52)/(R51-R52) < 0; where R51 is the radius of curvature of the object-side surface S5 of the fifth lens element 5 on the optical axis OO ', and R52 is the radius of curvature of the image-side surface F5 of the fifth lens element 5 on the optical axis OO'. That is, the sum of R51 and R52, divided by the difference between R51 and R52, may be within the range of (-3.33, 0), for example, -3, -2, -1, -0.7.

Therefore, the object-side surface S5 of the fifth lens element 5 is concave at the paraxial region OO', so that the incident angle is small when the chief ray is incident on the surface of the lens element, the curvature radius of the fifth lens element 5 is optimized reasonably, the focal power is restricted within a certain range, and the meridional astigmatism and the off-axis coma can be corrected conveniently.

In certain embodiments, the imaging optical system 10 satisfies the following conditional expressions: -5.5< f5/f < -1; where f5 is the focal length of the fifth lens 5. I.e., the result of dividing f5 by f is within the interval (-5.5, -1), e.g., the result may be-5, -4.9, -3, -2.7, -2, -1.8, -1.3, etc. Therefore, the fifth lens 5 provides negative focal power, the ratio of f5/f can be reasonably configured, the distortion and the aberration of the imaging optical system 10 can be effectively corrected, and good imaging quality is ensured. If the negative power of the fifth lens 5 is too large above the upper limit of the expression, the higher order aberration increases, and if the negative power of the fifth lens 5 is too small below the lower limit of the expression, the aberration correction is insufficient.

Alternatively, the imaging optical system 10 satisfies the following conditional expression: -18.6< SAG51/SAG61< 7.4; namely, the result of dividing SAG51 by SAG61 is within the interval (-18.6,7.4), where SAG51 is the axial distance from the intersection of the object-side surface S5 of the fifth lens 5 and the optical axis OO 'to the projection of the optically effective zone edge of the object-side surface S5 of the fifth lens 5 on the optical axis OO', and SAG61 is the axial distance from the intersection of the object-side surface S6 of the sixth lens 6 and the optical axis OO 'to the projection of the optically effective zone edge of the object-side surface of the sixth lens 6 on the optical axis OO'.

Therefore, the fifth lens 5 and the sixth lens 6 keep the same-direction bending degree, the assembly production is facilitated, the bending amplitude of the fifth lens 5 is obvious, the rise absolute value is large, the purpose is to correct the distortion of the marginal field of view and restrain the excessive increase of optical distortion, and the ratio of SAG51/SAG61 is controlled to enable the two lenses to be matched more closely, and the resolving power is improved.

In some embodiments, the imaging optical system 10 further includes: the diaphragm 7 is disposed in the middle, and the diaphragm 7 is disposed between the image-side surface F2 of the second lens 2 and the object-side surface S3 of the third lens 3. The diaphragm 7 may be an aperture diaphragm or a field diaphragm. The diaphragm 7 arranged in the middle can better control the light quantity, improve the integral brightness of imaging, ensure that the imaging surface meets the requirement of a larger light receiving area, and improve the imaging effect. The diaphragm is arranged in the middle, so that the eccentric inclination sensitivity of the system is reduced, and the production yield can be effectively improved. In the telephoto lens, the aperture of the diaphragm is reduced.

In some embodiments, the material of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6 is plastic or glass. The plastic lens has low cost, which is beneficial to reducing the cost of the imaging optical system 10; the glass lens is not easy to expand with heat and contract with cold due to the change of the environmental temperature, so that the imaging quality of the imaging optical system 10 is relatively stable.

In some embodiments, the object-side surface and the image-side surface of at least one of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6 are aspheric. The aspherical surface shape is determined by the following formula:

where Z is the longitudinal distance between any point on the aspheric surface and the surface vertex, r is the distance from any point on the aspheric surface to the optical axis OO', c is the vertex curvature (inverse of the radius of curvature), k is the conic constant, and Ai is the correction coefficient of the i-th order of the aspheric surface. In this way, the imaging optical system 10 can effectively reduce the total length of the imaging optical system 10 by the curvature radius and the aspheric coefficient of each lens surface, and can effectively correct the aberration and improve the imaging quality.

Specifically, the object-side surface and the image-side surface of the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, and the sixth lens 6 are aspheric. In order to embody the solution of the present application, the structures and parameters of the imaging optical system 10 of the seven embodiments are shown below.

First embodiment

Referring to fig. 1 to 4, from the object side to the image side, the imaging optical system 10 of the first embodiment sequentially includes a first lens 1, a second lens 2, a stop 7, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and an infrared filter 9 along an optical axis OO'. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The first lens element 1 has positive optical power, the object-side surface S1 is convex at the paraxial region OO ', the image-side surface F1 is convex at the paraxial region OO', and both the object-side surface S1 and the image-side surface F1 are aspheric. The second lens element 2 has negative power, the object-side surface S2 is convex at the paraxial region OO ', the image-side surface F2 is concave at the paraxial region OO', and both the object-side surface S2 and the image-side surface F2 are aspheric. The third lens element 3 has negative power, and has a concave object-side surface S3 at the paraxial region OO ', a convex image-side surface F3 at the paraxial region OO', and aspheric object-side surface S3 and image-side surface F3. The fourth lens element 4 has positive optical power, with an object-side surface S4 being concave at the paraxial region OO ', an image-side surface F4 being convex at the paraxial region OO', and both the object-side surface S4 and the image-side surface F4 being aspheric. The fifth lens element 5 has negative power, and has a concave object-side surface S5 at the paraxial region OO ', a concave image-side surface F5 at the paraxial region OO', and aspheric object-side surface S5 and image-side surface F5. The sixth lens element 6 has positive optical power, with an object-side surface S6 being convex at the paraxial region OO ', an image-side surface F6 being concave at the paraxial region OO', and both the object-side surface S6 and the image-side surface F6 being aspheric.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 1

Where EFL is an effective focal length of the imaging optical system 10, FNO is an f-number of the imaging optical system 10, HFOV is a half of a maximum field angle of the imaging optical system 10, and TTL is a distance from the object-side surface S1 of the first lens element 1 to the imaging surface on the optical axis OO'.

Table 2 shows the conic coefficient K and the higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, a20 of the first embodiment corresponding to the aspherical mirror surfaces of table 1, the

surface numbers

1, 2, 3, 4, 6,7, 8, 9, 10, 11, 12, 13, which are obtained by the above aspherical surface formula (10):

TABLE 2

Fig. 2 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the first embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 2 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the first embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the first embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 3 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the first embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.3 mm to 0.3 mm. As can be seen from fig. 3, the field curvature of the imaging optical system 10 of the first embodiment is small, the field curvature and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 4 is a Distortion diagram (aberration) of the imaging optical system 10 according to the first embodiment, which shows that the Distortion ratio of the light with a wavelength of 587.56nm is within a range of ± 5.0% after passing through the imaging optical system 10. As can be seen from fig. 4, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Second embodiment

Referring to fig. 5 to 8, from the object side to the image side, the imaging optical system 10 of the second embodiment sequentially includes a first lens 1, a second lens 2, a stop 7, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and an infrared filter 9 along an optical axis OO'. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The first lens element 1 has positive optical power, the object-side surface S1 is convex at the paraxial region OO ', the image-side surface F1 is convex at the paraxial region OO', and both the object-side surface S1 and the image-side surface F1 are aspheric. The second lens element 2 has negative power, the object-side surface S2 is convex at the paraxial region OO ', the image-side surface F2 is concave at the paraxial region OO', and both the object-side surface S2 and the image-side surface F2 are aspheric. The third lens element 3 has negative power, and has a concave object-side surface S3 at the paraxial region OO ', a convex image-side surface F3 at the paraxial region OO', and aspheric object-side surface S3 and image-side surface F3. The fourth lens element 4 has negative power, the object-side surface S4 is convex at the paraxial region OO ', the image-side surface F4 is concave at the paraxial region OO', and both the object-side surface S4 and the image-side surface F4 are aspheric. The fifth lens element 5 has negative power, and has a concave object-side surface S5 at the paraxial region OO ', a concave image-side surface F5 at the paraxial region OO', and aspheric object-side surface S5 and image-side surface F5. The sixth lens element 6 has positive optical power, with an object-side surface S6 being convex at the paraxial region OO ', an image-side surface F6 being concave at the paraxial region OO', and both the object-side surface S6 and the image-side surface F6 being aspheric.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 3

Table 4 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the second embodiment corresponding to the aspherical mirror surfaces of table 3, which are given by the above aspherical surface type equation (10):

TABLE 4

Fig. 6 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the second embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 6 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.02 mm to 0.02 mm. As can be seen from the longitudinal spherical aberration diagram of the second embodiment, the convergent focus deviation degrees of the light rays with different wavelengths in the second embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 7 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the second embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 7, the field curvature of the imaging optical system 10 of the second embodiment is small, the field curvature and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 8 is a Distortion diagram (aberration) of the imaging optical system 10 according to the second embodiment, which shows that the Distortion ratio of the light with a wavelength of 587.56nm is within a range of ± 5.0% after passing through the imaging optical system 10. As can be seen from fig. 8, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Third embodiment

Referring to fig. 9 to 12, from the object side to the image side, the imaging optical system 10 of the third embodiment sequentially includes, along an optical axis OO', a first lens 1, a second lens 2, a stop 7, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and an infrared filter 9. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The first lens element 1 has positive optical power, the object-side surface S1 is convex at the paraxial region OO ', the image-side surface F1 is convex at the paraxial region OO', and both the object-side surface S1 and the image-side surface F1 are aspheric. The second lens element 2 has negative power, the object-side surface S2 is convex at the paraxial region OO ', the image-side surface F2 is concave at the paraxial region OO', and both the object-side surface S2 and the image-side surface F2 are aspheric. The third lens element 3 has positive optical power, the object-side surface S3 is concave at the paraxial region OO ', the image-side surface F3 is convex at the paraxial region OO', and both the object-side surface S3 and the image-side surface F3 are aspheric. The fourth lens element 4 has positive optical power, with an object-side surface S4 being concave at the paraxial region OO ', an image-side surface F4 being convex at the paraxial region OO', and both the object-side surface S4 and the image-side surface F4 being aspheric. The fifth lens element 5 has negative power, and has a concave object-side surface S5 at the paraxial region OO ', a convex image-side surface F5 at the paraxial region OO', and aspheric object-side surface S5 and image-side surface F5. The sixth lens element 6 has negative power, and has a convex object-side surface S6 at the paraxial region OO ', a concave image-side surface F6 at the paraxial region OO', and aspheric object-side surface S6 and image-side surface F6.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 5

Table 6 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the third embodiment corresponding to the aspherical mirror surfaces of table 5, which are given by the above aspherical surface type equation (10):

TABLE 6

Fig. 10 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the third embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 10 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the third embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the third embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 11 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the third embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 11, the field curvature of the imaging optical system 10 of the third embodiment is small, the field curvature and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 12 is a Distortion diagram (aberration) of the imaging optical system 10 according to the third embodiment, in which the Distortion ratio of the light having a wavelength of 587.56nm passing through the imaging optical system 10 is within a range of ± 5.0%. As can be seen from fig. 12, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Fourth embodiment

Referring to fig. 13 to 16, from the object side to the image side, the imaging optical system 10 of the fourth embodiment sequentially includes, along an optical axis OO', a first lens 1, a second lens 2, a stop 7, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and an infrared filter 9. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The first lens element 1 has positive optical power, the object-side surface S1 is convex at the paraxial region OO ', the image-side surface F1 is convex at the paraxial region OO', and both the object-side surface S1 and the image-side surface F1 are aspheric. The second lens element 2 has negative power, the object-side surface S2 is convex at the paraxial region OO ', the image-side surface F2 is concave at the paraxial region OO', and both the object-side surface S2 and the image-side surface F2 are aspheric. The third lens element 3 has negative power, and has a concave object-side surface S3 at the paraxial region OO ', a convex image-side surface F3 at the paraxial region OO', and aspheric object-side surface S3 and image-side surface F3. The fourth lens element 4 has positive optical power, with an object-side surface S4 being convex at the paraxial region OO ', an image-side surface F4 being concave at the paraxial region OO', and both the object-side surface S4 and the image-side surface F4 being aspheric. The fifth lens element 5 has negative power, and has a concave object-side surface S5 at the paraxial region OO ', a convex image-side surface F5 at the paraxial region OO', and aspheric object-side surface S5 and image-side surface F5. The sixth lens element 6 has negative power, and has a convex object-side surface S6 at the paraxial region OO ', a concave image-side surface F6 at the paraxial region OO', and aspheric object-side surface S6 and image-side surface F6.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 7

Table 8 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the fourth embodiment corresponding to the aspherical mirror surfaces of table 7, the

surface numbers

1, 2, 3, 4, 6,7, 8, 9, 10, 11, 12, and 13, which are obtained by the above aspherical surface formula (10):

TABLE 8

Fig. 14 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the fourth embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 14 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the fourth embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the fourth embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 15 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the fourth embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 15, the field curvature of the imaging optical system 10 of the fourth embodiment is small, the field curvature and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 16 is a Distortion diagram (aberration) of the imaging optical system 10 according to the fourth embodiment, in which the Distortion ratio of light having a wavelength of 587.56nm passing through the imaging optical system 10 is within a range of ± 5.0%. As can be seen from fig. 16, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Fifth embodiment

Referring to fig. 17 to 20, the imaging optical system 10 of the fifth embodiment sequentially includes, along an optical axis OO', a first lens element 1, a second lens element 2, a stop 7, a third lens element 3, a fourth lens element 4, a fifth lens element 5, a sixth lens element 6, and an infrared filter 9 from an object side to an image side. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The first lens element 1 has positive optical power, the object-side surface S1 is convex at the paraxial region OO ', the image-side surface F1 is convex at the paraxial region OO', and both the object-side surface S1 and the image-side surface F1 are aspheric. The second lens element 2 has negative power, the object-side surface S2 is convex at the paraxial region OO ', the image-side surface F2 is concave at the paraxial region OO', and both the object-side surface S2 and the image-side surface F2 are aspheric. The third lens element 3 has positive optical power, the object-side surface S3 is concave at the paraxial region OO ', the image-side surface F3 is convex at the paraxial region OO', and both the object-side surface S3 and the image-side surface F3 are aspheric. The fourth lens element 4 has negative power, and has a concave object-side surface S4 at the paraxial region OO ', a convex image-side surface F4 at the paraxial region OO', and aspheric object-side surface S4 and image-side surface F4. The fifth lens element 5 has negative power, and has a concave object-side surface S5 at the paraxial region OO ', a convex image-side surface F5 at the paraxial region OO', and aspheric object-side surface S5 and image-side surface F5. The sixth lens element 6 has negative power, and has a convex object-side surface S6 at the paraxial region OO ', a concave image-side surface F6 at the paraxial region OO', and aspheric object-side surface S6 and image-side surface F6.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 9

Table 10 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the fifth embodiment corresponding to the aspherical mirror surfaces of table 9, which are given by the above aspherical surface type equation (10):

watch 10

Fig. 18 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the fifth embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 18 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the fifth embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the fifth embodiment are consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 19 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the fifth embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 19, the field curvature of the imaging optical system 10 of the fifth embodiment is small, the field curvature and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 20 is a Distortion diagram (aberration) of the imaging optical system 10 of the fifth embodiment, showing that the Distortion ratio of light having a wavelength of 587.56nm after passing through the imaging optical system 10 is within a range of ± 5.0%. As can be seen from fig. 20, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Sixth embodiment

Referring to fig. 21 to 24, the imaging optical system 10 of the sixth embodiment sequentially includes, along an optical axis OO', a first lens element 1, a second lens element 2, a stop 7, a third lens element 3, a fourth lens element 4, a fifth lens element 5, a sixth lens element 6, and an infrared filter 9 from an object side to an image side. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The imaging optical system 10 satisfies the conditions of the following table:

TABLE 11

Table 12 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the sixth embodiment corresponding to the aspherical mirror surfaces of table 11, which are given by the above aspherical surface type equation (10), in table 11:

TABLE 12

Fig. 22 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the sixth embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 22 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the sixth embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the sixth embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 23 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the sixth embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 23, the curvature of field of the imaging optical system 10 of the sixth embodiment is small, the curvature of field and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 24 is a Distortion diagram (aberration) of the imaging optical system 10 according to the sixth embodiment, which shows that the Distortion ratio of light having a wavelength of 587.56nm after passing through the imaging optical system 10 is within a range of ± 5.0%. As can be seen from fig. 24, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

Seventh embodiment

Referring to fig. 25 to 28, from the object side to the image side, the imaging optical system 10 of the seventh embodiment sequentially includes, along an optical axis OO', a first lens 1, a second lens 2, a stop 7, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, and an infrared filter 9. The reference wavelengths of the refractive index, Abbe number and focal length of each lens are 587.56 nm.

The imaging optical system 10 satisfies the conditions of the following table:

watch 13

Table 14 shows the conic coefficient K and higher order correction coefficients a4, a6, A8, a10, a12, a14, a16, a18, and a20 of the seventh embodiment corresponding to the aspherical mirror surfaces of table 3, which are given by the above aspherical surface type equation (10):

TABLE 14

Fig. 26 is a Longitudinal Spherical Aberration diagram (Longitudinal Spherical Aberration) of the seventh embodiment, which shows the convergent focus deviation of light rays of different wavelengths after passing through the imaging optical system 10. The ordinate of the diagram represents the Normalized Pupil coordinate (Normalized Pupil Coordinator) from the Pupil center to the Pupil edge, and the abscissa of the diagram represents the distance (in mm) of the imaging plane to the intersection of the ray with the optical axis OO'. The wavelengths of light rays used in fig. 26 are 486.13nm, 587.56nm, and 656.27nm, respectively, and the focus offset of the three light rays after being converged by the imaging optical system 10 is in the range of-0.05 mm to 0.05 mm. As can be seen from the longitudinal spherical aberration diagram of the seventh embodiment, the convergent focus deviation degrees of the light beams with different wavelengths in the seventh embodiment tend to be consistent, and the diffuse speckle or the chromatic halo in the imaging picture is effectively suppressed.

Fig. 27 is a Field curvature diagram (volumetric Field Curves) of the imaging optical system 10 according to the seventh embodiment, in which the S-curve represents sagittal Field curvature at 587.56nm and the T-curve represents meridional Field curvature at 587.56 nm. After light with the wavelength of 587.56nm passes through the imaging optical system 10, the focus offset of sagittal curvature of field and tangential curvature of field is in the range of-0.2 mm to 0.2 mm. As can be seen from fig. 27, the curvature of field of the imaging optical system 10 of the seventh embodiment is small, the curvature of field and astigmatism of each field (particularly, the peripheral field) are well corrected, and the center and the periphery of the field have sharp images.

Fig. 28 is a Distortion diagram (aberration) of the imaging optical system 10 according to the seventh embodiment, in which the Distortion ratio of light having a wavelength of 587.56nm passing through the imaging optical system 10 is within a range of ± 5.0%. As can be seen from fig. 28, the image distortion caused by the main beam is small, and the imaging quality of the imaging optical system 10 is excellent.

The seven embodiments above, summarized the following characteristics:

watch 15

The imaging optical system 10 provided by the application can meet the micro-telephoto characteristic of the mobile phone lens, and the six-piece optical structure ensures higher resolving power, expands the field angle and obtains wider shooting pictures under the condition of having the telephoto characteristic. Can be applied to a small-sized image pickup device.

The image capturing module of the present invention includes the imaging optical system 10 and the electronic photosensitive element of any one of the above embodiments. The electron-sensitive element is disposed on the image side of the imaging optical system 10, and alternatively, a Complementary Metal Oxide Semiconductor (CMOS) image sensor or a Charge-coupled Device (CCD) image sensor may be used as the electron-sensitive element.

The utility model discloses get for instance the module and dispose through reasonable lens for under the condition that imaging optical system 10 has the long focal characteristic, enlarge the angle of vision, obtain wider shooting picture. According to the utility model discloses electron device includes the getting for instance module of casing and above-mentioned embodiment, gets for instance the module and installs on the casing in order to acquire the image. The utility model discloses embodiment's electron device passes through reasonable lens configuration, has under the condition of long focal characteristic, enlarges the angle of vision, obtains wider shooting picture. The electronic device according to the embodiment of the present invention includes, but is not limited to, a miniaturized smart phone, a mobile phone, a Personal Digital Assistant (PDA), a game machine, an information terminal device such as a PC, a home appliance having a camera function, and the like.

In the description herein, references to the description of the terms "embodiment," "example," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An imaging optical system comprising, in order from an object side to an image side along an optical axis:

a first lens having an optical power;

a second lens having an optical power;

a third lens having optical power;

a fourth lens having an optical power;

a fifth lens having optical power;

a sixth lens having optical power;

the imaging optical system satisfies the conditional expression: HFOV >25 degrees, f/TTL > 1;

the HFOV is a half of a maximum field angle of the imaging optical system, f is an effective focal length of the imaging optical system, and TTL is a distance from an object side surface of the first lens to an imaging surface on an optical axis.

2. Imaging optical system according to claim 1,

the first lens has a positive optical power, and the object side surface of the first lens is convex at a paraxial region;

the second lens has a negative optical power; the fifth lens has a negative optical power, and an object side surface of the fifth lens is concave at a paraxial region.

3. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: 0< T56/CT6< 0.93;

wherein T56 is the air space between the fifth lens and the sixth lens on the optical axis, and CT6 is the central thickness of the sixth lens on the optical axis.

4. The imaging optical system according to claim 1, wherein an object-side surface of the sixth lens element is convex at a paraxial region, an image-side surface of the sixth lens element is concave at a paraxial region, and at least one of the object-side surface and the image-side surface of the sixth lens element has an inflection point.

5. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: 0< | f5/f6| < 2.6;

wherein f5 is the focal length of the fifth lens, and f6 is the focal length of the sixth lens.

6. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: 0.46< ImgH/f < 0.52;

wherein ImgH is half of the image height corresponding to the maximum field angle of the imaging optical system.

7. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: -0.1< f2/f34< 0.1;

wherein f2 is the focal length of the second lens, and f34 is the combined focal length of the third lens and the fourth lens.

8. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: -3.33< (R51+ R52)/(R51-R52) < 0;

wherein R51 is a radius of curvature at the optical axis of the object-side surface of the fifth lens, and R52 is a radius of curvature at the optical axis of the image-side surface of the fifth lens.

9. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: -5.5< f5/f < -1;

wherein f5 is the focal length of the fifth lens.

10. The imaging optical system according to claim 1, characterized in that the imaging optical system satisfies the following conditional expression: -18.6< SAG51/SAG61< 7.4;

SAG51 is the axial distance from the intersection point of the object side surface of the fifth lens and the optical axis to the projection of the optically effective area edge of the object side surface of the fifth lens on the optical axis, and SAG61 is the axial distance from the intersection point of the object side surface of the sixth lens and the optical axis to the projection of the optically effective area edge of the object side surface of the sixth lens on the optical axis.

11. The imaging optical system according to any one of claims 1 to 10, characterized by further comprising: a stop disposed in the middle between an image-side surface of the second lens and an object-side surface of the third lens.

12. An image capturing module, comprising:

the imaging optical system of any one of claims 1 to 11; and

and the electronic photosensitive element is arranged on the image side of the imaging optical system.

13. An electronic device, comprising:

a housing; and

the image capture module of claim 12, mounted on the housing.