Monofocal photographing lens assembly

A monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has a concave image-side surface. The second lens element has refractive power. The third lens element has refractive power. The fourth lens element has refractive power. The fifth lens element has negative refractive power. The sixth lens element with positive refractive power has a convex image-side surface.

RELATED APPLICATIONS

The application claims priority to Taiwan Application Serial Number 101132175, filed on Sep. 4, 2012, which is herein incorporated by reference.

BACKGROUND

1. Technical Field

The present invention relates to a monofocal photographing lens assembly. More particularly, the present invention relates to a compact monofocal photographing lens assembly applicable to electronic products.

2. Description of Related Art

In recent years, the applications of an optical lens system are getting wider, especially in vehicle image system, image security system, internet video, mobile device, and compact camera. The image sensor of a conventional optical lens system is typically a CCD (Charge-Coupled Device) sensor or a CMOS (Complementary Metal-Oxide Semiconductor) sensor. As the advanced semiconductor manufacturing technologies have allowed the pixel size of the sensors to be reduced and compact optical lens system have gradually evolved toward the field of higher megapixels, there is an increasing demand for optical lens system featuring better image quality.

A conventional optical lens system with a large field of view mainly adopts lens element with negative refractive power near an object side, and adopts lens elements with positive refractive power near an image side, thus an inverse telephoto structure is formed for obtaining a larger field of view, such as a four-element optical lens system disclosed in U.S. Pat. No. 7,446,955.

Although other conventional optical lens systems with five-element lens structure such as the ones disclosed in U.S. Pat. No. 8,248,713 enhance image quality and resolving power, these optical designs still reside with unsolved problems. Since the outer diameter of each lens element of the conventional optical lens system has dramatic variation in geometry, it is not favorable for assembling the lens elements so as to decrease manufacturing yield rate, and the difficulty in lens barrel design also increases. As demands on vehicle image system, image security system, and internet video device are increasing, there exits a need on a monofocal photographing lens assembly with large field of view, excellent image quality, simple design, and high manufacturing yield rate.

SUMMARY

According to one aspect of the present disclosure, a monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element. The first lens element with negative refractive power has a concave image-side surface. The second lens element has refractive power. The third lens element has refractive power. The fourth lens element has refractive power. The fifth lens element has negative refractive power. The sixth lens element with positive refractive power has a convex image-side surface. When a sum of central thicknesses of the first through sixth lens elements is ΣCT, an axial distance between an object-side surface of the first lens element and the image-side surface of the sixth lens element is Td, a focal length of the monofocal photographing lens assembly is f, a focal length of the first lens element is f1 and an f-number of the monofocal photographing lens assembly is Fno, the following relationships are satisfied: 1.0<Td/ΣCT<1.35; −1.5<f/f1<−0.6; and 1.5<Fno<3.0.

According to another aspect of the present disclosure, a monofocal photographing lens assembly includes, in order from an object side to an image side, a front lens group, a stop, and a rear lens group. The front lens group includes a first lens element and a second lens element. The first lens element with negative refractive power has concave image-side surface. The second lens element has refractive power. The rear lens group includes a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element. The third lens element with refractive power has a convex image-side surface. The fourth lens element has refractive power. The fifth lens element has negative refractive power. The sixth lens element with positive refractive power has a convex image-side surface. When a sum of central thicknesses of the first through sixth lens elements is ΣCT, an axial distance between an object-side surface of the first lens element and the image-side surface of the sixth lens element is Td, a focal length of the monofocal photographing lens assembly is f, and a focal length of the first lens element is f1, the following relationships are satisfied: 1.0<Td/ΣCT<1.35; and −1.5<f/f1<−0.6.

DETAILED DESCRIPTION

A monofocal photographing lens assembly is provided. The monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element.

Another monofocal photographing lens assembly is provided. The monofocal photographing lens assembly includes, in order from an object side to an image side, a front lens group, a stop, and a rear lens group, wherein the stop can be an aperture stop. The front lens group includes, in order from an object side to an image side, a first lens element, and a second lens element. The rear lens group includes, in order from an object side to an image side, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element.

The first lens element with negative refractive power has a concave image-side surface, so that the field of view of the monofocal photographing lens assembly can be expanded.

The second lens element can have a convex object-side surface, so that the total track length of the monofocal photographing lens assembly can be reduced.

The third lens element can have positive refractive power, so that the sensitivity of the monofocal photographing lens assembly can be reduced. The third lens element has a convex image-side surface, so that it is favorable for reducing the total track length of the monofocal photographing lens assembly. Furthermore, an air space can be formed between the second lens element and the third lens element, so that it is favorable for assembling the lens elements to enhance the manufacturing yield rate.

The fourth lens element can have a convex object-side surface and a convex image-side surface, so that the spherical aberration of the monofocal photographing lens assembly can be corrected.

The fifth lens element can have negative refractive and a concave image-side surface, so that the high order aberration of the monofocal photographing lens assembly can be corrected. Furthermore, an air space can be formed between the fourth lens element and the fifth lens element, so that it is favorable for assembling the lens elements to enhance the manufacturing yield rate.

The sixth lens element has a convex image-side surface with positive refractive power, and can have a convex object-side surface. Therefore, the distribution of the positive refractive power of the monofocal photographing lens assembly can be balanced. Furthermore, the angle of the incident light to an image sensor can be reduced for better sensor response efficiency, and the image quality can be enhanced. Moreover, the fifth lens element can be cemented with the sixth lens element, so that the chromatic aberration can be corrected.

When a sum of central thicknesses of the first through sixth lens elements is ΣCT, and an axial distance between an object-side surface of the first lens element and the mage-side surface of the sixth lens element is Td, the following relationship is satisfied 1.0<Td/ΣCT<1.35. Therefore, it is favorable for assembling the lens elements by properly adjusting the thicknesses and the distance between each lens element. Moreover, similar geometry of the outer diameter of each lens element is favorable for the design and manufacturing of the barrel. Preferably, ΣCT and Td can satisfy the following relationship: 1.0<Td/ΣCT<1.25.

When a focal length of the monofocal photographing lens assembly is f, and a focal length of the first lens element is f1 the following relationship is satisfied: −1.5<−0.6. Therefore, a field of view of the monofocal photographing lens assembly can be enlarged by properly adjusting the negative refractive power of the first lens element. Preferably, f and f1 can satisfy the following relationship: −1.2<f/f1<−0.75.

When an f-number of the monofocal photographing lens assembly is Fno, the following relationship is satisfied: 1.5<Fno<3.0. Therefore, advantages of a large aperture arrangement of the monofocal photographing lens assembly can be obtained. Furthermore, a clear image can be obtained under low light condition with a high speed shutter due to the larger aperture of the monofocal photographing lens assembly. Preferably, Fno can satisfy the following relationship: 1.8<Fno<2.5.

When the focal length of the monofocal photographing lens assembly is f, and a focal length of the second lens element is f2, the following relationship is satisfied: −0.5<f/f2<0.5. Therefore, the total track length of the monofocal photographing lens assembly can be reduced by properly adjusting the refractive power of the second lens element. Preferably, f and f2 can satisfy the following relationship: −0.3<f/f2<0.3.

When half of a maximal field of view of the monofocal photographing lens assembly is HFOV, the following relationship is satisfied: 70 degrees<HFOV<100 degrees. An excessively large field of view would produce a more pronounced image distortion at the peripheral region thereof: an insufficient field of view would overly constrain the imaging field. Therefore, the proper field of view of the monofocal photographing lens assembly can reduce image distortions so as to improve image quality.

When a relative illumination at an 80% position of a maximal image height on an image plane of the monofocal photographing lens assembly is RI—0.8F, the following relationship is satisfied: 70%<RI—0.8F. Therefore, the sufficient illumination within the imaging range can provide notable improvements in the image quality.

When an effective radius of the object-side surface of the first lens element is SD11, and an effective radius of the image-side surface of the sixth lens element is SD62, the following relationship is satisfied: 0.8<SD11/SD62<1.3. Therefore, the incident angle of the light can be effectively reduced and the off-axis aberration can be corrected as well.

When an axial distance between the object-side surface of the first lens element and the stop is Dr1s, and an axial distance between the stop and the image-side surface of the sixth lens element is Dsr12 the following relationship is satisfied: 0.4<Dr1s/Dsr12<1.0. Therefore, a field of view of the monofocal photographing lens assembly can be enlarged by properly adjusting the position of the stop, and thereby increase the viewable range.

When the focal length of the monofocal photographing lens assembly is f, the focal length of the first lens element is f1, the focal length of the second lens element is f2, a focal length of the third lens element is f3, a focal length of the fourth lens element is f4, a focal length of the fifth lens element is f5, and a focal length of the sixth lens element is f6, the following relationships are satisfied: |f/f1|>|f/f2|, |f/f1|>|f/f3|, |f/f1|>|f/f4|, |f/f1|>|f/f5|, and |f/f1|>|f/f6|. Therefore, the field of view of the monofocal photographing lens assembly can be enlarged by the proper refractive power of the first lens element, and thereby increase the viewable range.

When an axial distance between the second lens element and the third lens element is T23, and an axial distance between the fourth lens element and the fifth lens element is T45, the following relationship is satisfied: 0.1 T45/T23<5. Therefore, it is favorable for assembling the lens elements and enhancing the manufacturing yield rate by properly adjusting the distance between each lens element.

When a refractive index of the sixth lens element is N6, the following relationship is satisfied: N6>1.7. Therefore, the distribution of the refractive power of the monofocal photographing lens assembly can be balanced due to the large positive refractive power of the sixth lens element.

According to the monofocal photographing lens assembly of the present disclosure, the lens elements thereof can be made of plastic or glass materials. When the lens elements are made of glass material, the allocation of the refractive power of the monofocal photographing lens assembly may be more flexible and easier to design. When the lens elements are made of plastic material, the manufacturing cost can be effectively reduced. Furthermore, the surface of each lens element can be aspheric, so that it is easier to make the surface into non-spherical shapes. As a result, more controllable variables are obtained for reducing the aberration, and the number of required lens elements for constructing a monofocal photographing lens assembly can be reduced. Therefore, the total track length of the monofocal photographing lens assembly can also be reduced.

According to the monofocal photographing lens assembly of the present disclosure, when a lens element has a convex surface, it indicates that the surface is convex at a paraxial region; and when a lens element has a concave surface, it indicates that the surface is concave at a paraxial region.

According to the monofocal photographing lens assembly of the present disclosure, the monofocal photographing lens assembly can include at least one stop, such as an aperture stop, a glare stop or a field stop. Said glare stop or said field stop is for eliminating the stray light and thereby improving the image resolution thereof.

In the present monofocal photographing lens assembly, an aperture stop can be configured as a front stop or a middle stop. A front stop disposed between an object and the first lens element can provide a longer distance between an exit pupil of the system and an image plane and which improves the image-sensing efficiency of an image sensor. A middle stop disposed between the first lens element and an image plane is favorable for enlarging the field of view of the system and thereby provides a wider field of view for the same.

According to the above description of the present disclosure, the following 1st-8th specific embodiments are provided for further explanation.

FIG. 1is a schematic view of a monofocal photographing lens assembly according to the 1st embodiment of the present disclosure.FIG. 2shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 1st embodiment. InFIG. 1, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element110, a second lens element120, an aperture stop100, a third lens element130, a fourth lens element140, a fifth lens element150, a sixth lens element160, an IR-cut filter180, a cover glass190, and an image plane170.

The first lens element110with negative refractive power made of glass material and has a convex object-side surface111and a concave image-side surface112.

The second lens element120with positive refractive power made of glass material and has a convex object-side surface121and a concave image-side surface122.

The third lens element130with positive refractive power made of glass material and has a concave object-side surface131and a convex image-side surface132. An air space is formed between the second lens element120and the third lens element130.

The fourth lens element140with positive refractive power made of glass material and has a convex object-side surface141and a convex image-side surface142.

The fifth lens element150with negative refractive power made of glass material and has a convex object-side surface151and a concave image-side surface152. An air space is formed between the fourth lens element140and the fifth lens element150.

The sixth lens element160with positive refractive power made of glass material and has a convex object-side surface161and a convex image-side surface162. The image-side surface152of the fifth lens element150is cemented with the object-side surface161of the sixth lens element160.

The IR-cut filter180is made of glass material, wherein the IR-cut filter180and the cover glass190are sequentially located between the sixth lens element160and the image plane170, and will not affect the focal length of the monofocal photographing lens assembly.

In the monofocal photographing lens assembly according to the 1st embodiment, when a focal length of the monofocal photographing lens assembly is f, an f-number of the monofocal photographing lens assembly is Fno, and a half of a maximal field of view of the monofocal photographing lens assembly is HFOV, these parameters have the following values:

Fno=2.00; and

In the monofocal photographing lens assembly according to the 1st embodiment, when a refractive index of the sixth lens element160is N6, the following relationship is satisfied: N6=1.729.

In the monofocal photographing lens assembly according to the 1st embodiment, when an axial distance between the second lens element120and the third lens element130is T23, and an axial distance between the fourth lens element140and the fifth lens element150is T45, the following relationship is satisfied: T45/T23=0.22.

In the monofocal photographing lens assembly according to the 1st embodiment, when the focal length of the monofocal photographing lens assembly is f, and a focal length of the first lens element10is f1, the following relationship is satisfied: f/f1=−0.94.

In the monofocal photographing lens assembly according to the 1st embodiment, when the focal length of the monofocal photographing lens assembly is f, and a focal length of the second lens element120is f2, the following relationship satisfied: f/f2=0.11.

In the monofocal photographing lens assembly according to the 1st embodiment, when a sum of central thicknesses of the first110through sixth 160 lens elements (110-160) is ΣCT, and an axial distance between the object-side surface111of the first lens element110and the image-side surface162of the sixth lens element160is Td, the following relationship is satisfied: Td/ΣCT=1.14.

In the monofocal photographing lens assembly according to the 1st embodiment, when an effective radius of the object-side surface111of the first lens element110is SD11, and an effective radius of the image-side surface162of the sixth lens element160is SD62, the following relationship is satisfied: SD11/SD62=1.01.

In the monofocal photographing lens assembly according to the 1st embodiment, when an axial distance between the object-side surface111of the first lens element110and the aperture stop100is Dr1s, and an axial distance between the aperture stop100and the image-side surface162of the sixth lens element160is Dsr12, the following relationship is satisfied: Dr1s/Dsr12=0.63.

In the monofocal photographing lens assembly according to the 1st embodiment, when a relative illumination at an 80% position of a maximal image height on the image plane170of the monofocal photographing lens assembly is RI—08F, or, in other word, a relative illumination at an 80% position of a maximal field on the image plane170is RI—0.8F, the following relationship is satisfied: RI—08F=98.0%.

The detailed optical data of the 1st embodiment are shown in Table 1 below.

In Table 1, the curvature radius, the thickness and the focal length are shown in millimeters (mm). Surface numbers 0-18 represent the surfaces sequentially arranged from the object-side to the image-side along the optical axis. This information related to Table 1 also applies to the Tables for the remaining embodiments, and so an explanation in this regard will not be provided again,

FIG. 3is a schematic view of a monofocal photographing lens assembly according to the 2nd embodiment of the present disclosure.FIG. 4shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 2nd embodiment. InFIG. 3, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element210, a second lens element220, an aperture stop200, a third lens element230, a fourth lens element240, a fifth lens element250, a sixth lens element260, an IR-cut filter280, a cover glass290, and an image plane270.

The first lens element210with negative refractive power made of glass material and has a concave object-side surface211and a concave image-side surface212.

The second lens element220with positive refractive power made of glass material and has a convex object-side surface221and a concave image-side surface222.

The third lens element230with positive refractive power made of glass material and has a planar object-side surface231and a convex image-side surface232. An air space is formed between the second lens element220and the third lens element230.

The fourth lens element240with positive refractive power made of glass material and has a convex object-side surface241and a convex image-side surface242.

The fifth lens element250with negative refractive power made of glass material and has a convex object-side surface251and a concave image-side surface252. An air space is formed between the fourth lens element240and the fifth lens element250.

The sixth lens element260with positive refractive power made of glass material and has a convex object-side surface261and a convex image-side surface262. The image-side surface252of the fifth lens element250is cemented with the object-side surface261of the sixth lens element260.

The IR-cut filter280is made of glass material, wherein the IR-cut filter280and the cover glass290are sequentially located between the sixth lens element260and the image plane270, and will not affect the focal length of the monofocal photographing lens assembly.

The detailed optical data of the 2nd embodiment are shown in Table 2 below.

In the monofocal photographing lens assembly according to the 2nd embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SDG2, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 2nd embodiment. Moreover, these parameters can be calculated from Table 2 as the following values and satisfy the following relationships:

FIG. 5is a schematic view of a monofocal photographing lens assembly according to the 3rd embodiment of the present disclosure.FIG. 6shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 3rd embodiment. InFIG. 5, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element310, a second lens element320, an aperture stop300, a third lens element330, a fourth lens element340, a fifth lens element350, a sixth lens element360, an IR-cut filter380, a cover glass390, and an image plane370.

The first lens element310with negative refractive power made of glass material and has a convex object-side surface311and a concave image-side surface312.

The second lens element320with positive refractive power made of glass material and has a convex object-side surface321and a concave image-side surface322.

The third lens element330with positive refractive power made of glass material and has a concave object-side surface331and a convex image-side surface332. An air space is formed between the second lens element320and the third lens element330.

The fourth lens element340with positive refractive power made of glass material and has a convex object-side surface341and a convex image-side surface342.

The fifth lens element350with negative refractive power made of glass material and has a convex object-side surface351and a concave image-side surface352. An air space is formed between the fourth lens element340and the fifth lens element350.

The sixth lens element360with positive refractive power made of glass material and has a convex object-side surface361and a convex image-side surface362. The image-side surface352of the fifth lens element350is cemented with the object-side surface361of the sixth lens element360.

The IR-cut filter380is made of glass material, wherein the IR-cut filter380and the cover glass390are sequentially located between the sixth lens element360and the image plane370, and will not affect the focal length of the monofocal photographing lens assembly.

The detailed optical data of the 3rd embodiment are shown in Table 3 below.

In the monofocal photographing lens assembly according to the 3rd embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 3rd embodiment. Moreover, these parameters can be calculated from Table 3 as the following values and satisfy the following relationships:

FIG. 7is a schematic view of a monofocal photographing lens assembly according to the 4th embodiment of the present disclosure.FIG. 8shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 4th embodiment. InFIG. 7, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element410, a second lens element420, an aperture stop400, a third lens element430, a fourth lens element440, a fifth lens element450, a sixth lens element460, an IR-cut filter480, a cover glass490, and an image plane470.

The first lens element410with negative refractive power made of glass material and has a convex object-side surface411and a concave image-side surface412.

The second lens element420with positive refractive power made of glass material and has a convex object-side surface421and a concave image-side surface422.

The third lens element430with positive refractive power made of glass material and has a concave object-side surface431and a convex image-side surface432. An air space is formed between the second lens element420and the third lens element430.

The fourth lens element440with positive refractive power made of glass material and has a convex object-side surface441and a convex image-side surface442, wherein the object-side surface441and the image-side surface442of the fourth lens element440are aspheric.

The fifth lens element450with negative refractive power made of glass material and has a convex object-side surface451and a concave image-side surface452. An air space is formed between the fourth lens element440and the fifth lens element450.

The sixth lens element460with positive refractive power made of glass material and has a convex object-side surface461and a convex image-side surface462. The image-side surface452of the fifth lens element450is cemented with the object-side surface461of the sixth lens element460.

The IR-cut filter480is made of glass material, wherein the IR-cut filter480and the cover glass490are sequentially located between the sixth lens element460and the image plane470, and will not affect the focal length of the monofocal photographing lens assembly.

The equation of the aspheric surface profiles of the aforementioned lens elements of the 4th embodiment is expressed as follows:

X is the relative distance of a point on the aspheric surface spaced at a distance V from the optical axis relative to the tangential plane at the aspheric surface vertex on the optical axis;

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

R is the curvature radius;

k is the conic coefficient; and

Ai is the i-th aspheric coefficient.

The detailed optical data of the 4th embodiment are shown in Table 4 and the aspheric surface data are shown in Table 5 below.

In Table 5, k represents the conic coefficient of the equation of the aspheric surface profiles according to the 4th embodiment. A1-A10 represent the aspheric coefficients ranging from the 1st order to the 10th order.

In the monofocal photographing lens assembly according to the 4th embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 4th embodiment. Moreover, these parameters can be calculated from Table 4 and Table 5 as the following values and satisfy the following relationships:

FIG. 9is a schematic view of a monofocal photographing lens assembly according to the 5th embodiment of the present disclosure.FIG. 10shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 5th embodiment. InFIG. 9, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element510, an aperture stop500, a second lens element520, a third lens element530, a fourth lens element540, a fifth lens element550, a sixth lens element560, an IR-cut filter580, a cover glass590, and an image plane570.

The first lens element510with negative refractive power made of glass material and has a convex object-side surface511and a concave image-side surface512.

The second lens element520with positive refractive power made of glass material and has a convex object-side surface521and a concave image-side surface522, wherein the object-side surface521and the image-side surface522of the second lens element520are aspheric.

The third lens element530with positive refractive power made of glass material and has a concave object-side surface531and a convex image-side surface532, wherein the object-side surface531and the image-side surface532of the third lens element530are aspheric. An air space is formed between the second lens element520and the third lens element530.

The fourth lens element540with positive refractive power made of glass material and has a convex object-side surface541and a convex image-side surface542, wherein the object-side surface541and the image-side surface542of the fourth lens element540are aspheric.

The fifth lens element550with negative refractive power made of glass material and has a concave object-side surface551and a concave image-side surface552, wherein the object-side surface551and the image-side surface552of the fifth lens element550are aspheric. An air space is formed between the fourth lens element540and the fifth lens element550.

The sixth lens element560with positive refractive power made of glass material and has a convex object-side surface561and a convex image-side surface562, wherein the object-side surface561and the image-side surface562of the sixth lens element560are aspheric.

The IR-cut filter580is made of glass material, wherein the IR-cut filter580and the cover glass590are sequentially located between the sixth lens element560and the image plane570, and will not affect the focal length of the monofocal photographing lens assembly.

The detailed optical data of the 5th embodiment are shown in Table 6 and the aspheric surface data are shown in Table 7 below.

In Table 7, k represents the conic coefficient of the equation of the aspheric surface profiles according to the 5th embodiment. A1-A10 represent the aspheric coefficients ranging from the 1st order to the 10th order.

In the monofocal photographing lens assembly according to the 5th embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—08F are the same as those stated in the 1st embodiment with corresponding values for the 5th embodiment. Moreover, these parameters can be calculated from Table 6 and Table 7 as the following values and satisfy the following relationships:

FIG. 11is a schematic view of a monofocal photographing lens assembly according to the 6th embodiment of the present disclosure.FIG. 12shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 6th embodiment. InFIG. 11, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element610, a second lens element620, an aperture stop600, a third lens element630, a fourth lens element640, a fifth lens element650, a sixth lens element660, an IR-cut filter680, a cover glass690, and an image plane670.

The first lens element610with negative refractive power made of glass material and has a convex object-side surface611and a concave image-side surface612, wherein the object-side surface611and the mage-side surface612of the first lens element610are aspheric.

The second lens element620with negative refractive power made of glass material and has a convex object-side surface621and a concave image-side surface622being aspheric.

The third lens element630with positive refractive power made of glass material and has a convex object-side surface631and a convex image-side surface632. An air space is formed between the second lens element620and the third lens element630.

The fourth lens element640with positive refractive power made of glass material and has a concave object-side surface641and a convex image-side surface642.

The fifth lens element650with negative refractive power made of glass material and has a convex object-side surface651and a concave image-side surface652. An air space is formed between the fourth lens element640and the fifth lens element650.

The sixth lens element660with positive refractive power made of glass material and has a convex object-side surface661and a convex image-side surface662. The image-side surface652of the fifth lens element650is cemented with the object-side surface661of the sixth lens element660.

The IR-cut filter680is made of glass material, wherein the IR-cut filter680and the cover glass690are sequentially located between the sixth lens element660and the image plane670, and will not affect the focal length of the monofocal photographing lens assembly.

The detailed optical data of the 6th embodiment are shown in Table 8 and the aspheric surface data are shown in Table 9 below.

In Table 9, k represents the conic coefficient of the equation of the aspheric surface profiles according to the 6th embodiment, A1-A10 represent the aspheric coefficients ranging from the 1st order to the 10th order.

In the monofocal photographing lens assembly according to the 6th embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 6th embodiment. Moreover, these parameters can be calculated from Table 8 and Table 9 as the following values and satisfy the following relationships:

FIG. 13is a schematic view of a monofocal photographing lens assembly according to the 7th embodiment of the present disclosure.FIG. 14shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 7th embodiment. InFIG. 13, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element710, a second lens element720, an aperture stop700, a third lens element730, a fourth lens element740, a fifth lens element750, a sixth lens element760, an IR-cut filter780, a cover glass790, and an image plane770.

The first lens element710with negative refractive power made of glass material and has a convex object-side surface711and a concave image-side surface712.

The second lens element720with positive refractive power made of plastic material and has a convex object-side surface721and a concave image-side surface722, wherein the object-side surface721and the image-side surface722of the second lens element720are aspheric.

The third lens element730with positive refractive power made of plastic material and has a convex object-side surface731and a convex image-side surface732, wherein the object-side surface731and the image-side surface732of the third lens element730are aspheric. An air space is formed between the second lens element720and the third lens element730.

The fourth lens element740with negative refractive power made of plastic material and has a convex object-side surface741and a concave image-side surface742, wherein the object-side surface741and the image-side surface742of the fourth lens element740are aspheric.

The fifth lens element750with negative refractive power made of glass material and has a convex object-side surface751and a concave image-side surface752. An air space is formed between the fourth lens element740and the fifth lens element750.

The sixth lens element760with positive refractive power made of glass material and has a convex object-side surface761and a convex image-side surface762. The image-side surface752of the fifth lens element750is cemented with the object-side surface761of the sixth lens element760.

The IR-cut filter780is made of glass material, wherein the IR-cut filter780and the cover glass790are sequentially located between the sixth lens element760and the image plane770, and will not affect the focal, length of the monofocal photographing lens assembly.

The detailed optical data of the 7th embodiment are shown in Table 10 and the aspheric surface data are shown in Table 11 below.

In Table 11, k represents the conic coefficient of the equation of the aspheric surface profiles according to the 7th embodiment. A1-A12 represent the aspheric coefficients ranging from the 1st order to the 12th order.

In the monofocal photographing lens assembly according to the 7th embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 7th embodiment. Moreover, these parameters can be calculated from Table 10 and Table 11 as the following values and satisfy the following relationships:

FIG. 15is a schematic view of a monofocal photographing lens assembly according to the 8th embodiment of the present disclosure.FIG. 16shows spherical aberration curves, astigmatic field curves and a distortion curve of the monofocal photographing lens assembly according to the 8th embodiment. InFIG. 15, the monofocal photographing lens assembly includes, in order from an object side to an image side, a first lens element810, a second lens element820, an aperture stop800, a third lens element830, a fourth lens element840, a fifth lens element850, a sixth lens element860, an IR-cut filter880, a cover glass890, and an image plane870.

The first lens element810with negative refractive power made of glass material and has a convex object-side surface811and a concave image-side surface812.

The second lens element820with positive refractive power made of glass material and has a convex object-side surface821and a convex image-side surface822.

The third lens element830with positive refractive power made of plastic material and has a convex object-side surface831and a convex image-side surface832, wherein the object-side surface831and the image-side surface832of the third lens element830are aspheric. An air space is formed between the second lens element820and the third lens element830.

The fourth lens element840with negative refractive power made of plastic material and has a concave object-side surface841and a concave image-side surface842, wherein the object-side surface841and the image-side surface842of the fourth lens element840are aspheric.

The fifth lens element850with negative refractive power made of glass material and has a convex object-side surface851and a concave image-side surface852. An air space is formed between the fourth lens element840and the fifth lens element850.

The sixth lens element860with positive refractive power made of glass material and has a convex object-side surface861and a convex image-side surface862. The image-side surface852of the fifth lens element850is cemented with the object-side surface861of the sixth lens element860.

The IR-cut filter880is made of glass material, wherein the IR-cut filter880and the cover glass890are sequentially located between the sixth lens element860and the image plane870, and will not affect the focal length of the monofocal photographing lens assembly.

The detailed optical data, of the 8th embodiment are shown in Table 12 and the aspheric surface data are shown in Table 13 below.

In Table 13, k represents the conic coefficient of the equation of the aspheric surface profiles according to the 8th embodiment. A1-A12 represent the aspheric coefficients ranging from the 1st order to the 12th order.

In the monofocal photographing lens assembly according to the 8th embodiment, the definitions of f, Fno, HFOV, N6, T23, T45, f1, f2, ΣCT, Td, SD11, SD62, Dr1s, Dsr12, and RI—0.8F are the same as those stated in the 1st embodiment with corresponding values for the 8th embodiment. Moreover, these parameters can be calculated from Table 12 and Table 13 as the following values and satisfy the following relationships: