KR20090067782A - High quality optical system - Google Patents

Abstract

A high definition optical system is provided to improve a color fringing phenomenon by correcting a chromatic aberration. A high definition imaging optical system includes an aperture stop, a first lens group(G1), a second lens group(G2), a third lens group(G3), and a fourth lens group(G4). The first lens group has a positive refractive power by having the first lens which is convex from the object side. The second lens group has a negative refractive power by having the second lens and the third lens. The second lens has the positive refractive power. The third lens has the negative refractive power. The third lens group has the positive refractive power by having the fourth lens which is convex upward. The fourth lens group has the negative refractive lens by having the firth lens which is concave upward.

Description

High Definition Optical System

The present invention relates to an imaging optical system. More particularly, the present invention relates to an imaging optical system. More particularly, the present invention relates to an imaging optical system, which is compact and has a high resolution and is mounted on a mobile communication terminal, a PDA, or the like. It relates to a high-definition imaging optical system that can be photographed easily.

In general, a camera module lens used in a mobile communication terminal is composed of two or three lenses in a low pixel class and three or four lenses in a high pixel class.

In other words, the lens employed in the camera module designed for the low pixel class can be composed of three lenses because the pixel size is relatively large and the resolution required on the screen is low, and in some cases, two lenses can be used. However, the lens employed in the camera module designed for the high pixel class is composed of three or four lenses because the pixel size is small and the resolution required on the screen is high.

When the imaging optical system is composed of three sheets, it is difficult to properly correct chromatic aberration. Therefore, by configuring the imaging optical system composed of four sheets, chromatic aberration correction can be facilitated and image quality can be improved.

Accordingly, the present invention is to solve the above problems, the purpose of which is high performance and compact to achieve a miniaturization, and to improve the resolution while also correcting the chromatic aberration (Chromatic Aberration) with good color bleeding in indoor or outdoor shooting (Color Fringing) It is an object of the present invention to provide a high-definition imaging optical system that can satisfactorily improve a phenomenon.

As a specific means for achieving the above object, the present invention, the aperture stop in order from the object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And a fourth lens group having a fifth lens concave toward the image and having negative refractive power; It provides a high-definition imaging optical system comprising a.

Preferably, the second lens group includes a second lens having a positive refractive power and a third lens having a negative refractive power.

More preferably, at least one side of any one of the fourth lens and the fifth lens has an aspherical surface shape.

More preferably, the following Conditional Expression 1 is satisfied with respect to the optical axis direction dimension of the optical system.

(Condition 1) 1.0 <TL / f <1.5

Here, TL is the distance from the side of the first lens object of the first lens group to the image surface, and f is the focal length of the whole optical system.

More preferably, the following Conditional Expression 2-1 is satisfied with respect to the refractive power of the first lens group.

(Condition 2-1) 0.5 <f1 / f <1.0

Here, f1 is a focal length of the first lens group.

More preferably, the following Conditional Expression 3-1 is satisfied with respect to the refractive power of the first and second lens groups.

(Condition 3-1) 1.1 <f12 / f <1.5

Here, f12 is a combined focal length of the first lens group and the second lens group.

More preferably, the following Conditional Expression 4-1 is satisfied with respect to the shape of the fourth lens.

(Condition 4-1) -2.5 <R_L4F / f <-1.0

Here, R_L4F is the radius of curvature of the object-side surface of the fourth lens.

More preferably, the following Conditional Expressions 5-1 and 5-2 are satisfied with respect to the Abbe number of the second and third lenses.

(Condition 5-1) 45 <V_L2 <71

(Condition 5-2) 23 <V_L3 <40

Here, V_L2 is the Abbe's number of the second lens and V_L3 is the Abbe's number of the third lens.

More preferably, the following Conditional Expression 6-1 is satisfied with respect to the refractive power of the first lens group and the fourth lens group.

(Condition 6-1) -1.4 <f3 / f4 <-0.8

Here, f3 is the focal length of the first lens group, and f4 is the focal length of the fourth lens group.

Preferably, the second lens group includes a second lens having negative refractive power and a third lens having positive refractive power.

More preferably, at least one side of any one of the fourth lens and the fifth lens has an aspherical surface shape.

More preferably, the following Conditional Expression 1 is satisfied with respect to the optical axis direction dimension of the optical system.

(Condition 1) 1.0 <TL / f <1.5

Here, TL is the distance from the side of the first lens object of the first lens group to the image surface, and f is the focal length of the whole optical system.

More preferably, the following Conditional Expression 2-2 is satisfied with respect to the refractive power of the first lens group.

(Condition 2-2) 0.4 <f1 / f <0.9

Here, f1 is a focal length of the first lens group.

More preferably, the following Conditional Expression 3-2 is satisfied with respect to the refractive power of the first and second lens groups.

(Condition 3-2) 1.1 <f12 / f <1.7

Here, f12 is a combined focal length of the first lens group and the second lens group.

More preferably, the following Conditional Expression 4-2 is satisfied with respect to the shape of the fourth lens.

(Condition 4-1) -3.0 <R_L4F / f <-0.0

Here, R_L4F is the radius of curvature of the object-side surface of the fourth lens.

More preferably, the following conditional expressions 5-3, 5-4 and 5-5 are satisfied with respect to the Abbe number of the first, second and third lenses.

(Condition 5-3) 50 <V_L1 <70

(Condition 5-4) 25 <V_L2 <45

(Condition 5-5) 50 <V_L3 <70

Here, V_L1 is the Abbe number of the first lens, V_L2 is the Abbe number of the second lens, and V_L3 is the Abbe number of the third lens.

More preferably, the following Conditional Expression 6-1 is satisfied with respect to the refractive power of the first lens group and the fourth lens group.

(Condition 6-2) -1.4 <f3 / f4 <-0.7

Here, f3 is the focal length of the first lens group, and f4 is the focal length of the fourth lens group.

Moreover, this invention is an aperture stop in order from an object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group in which the image side surface of the second lens having positive refractive power and the object side surface of the third lens having negative refractive power are bonded or separated from each other and have negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And a fourth lens group having a negative refractive power by having a fifth lens concave toward the image and having at least one side as an aspherical surface; It provides a high-definition imaging optical system comprising a, satisfies the following conditional formula 1 with respect to the optical axis direction dimension of the optical system, and satisfies the following conditional formula 2-1 with respect to the refractive power of the first lens.

(Condition 1) 1.0 <TL / f <1.5

(Condition 2-1) 0.5 <f1 / f <1.0

Here, TL is the distance from the first lens object side surface of the first lens group to the image surface, and f is the focal length of the entire optical system. f1 is a focal length of the first lens.

More preferably, the following Conditional Expression 3-1 is satisfied with respect to the refractive power of the first and second lens groups.

(Condition 3-1) 1.1 <f12 / f <1.5

Here, f12 is a combined focal length of the first lens group and the second lens group.

And this invention is aperture diaphragm in order from an object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group in which an image side surface of the second lens having negative refractive power and an object side surface of the third lens having positive refractive power are bonded or separated from each other, and have negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And a fourth lens group having a negative refractive power by having a fifth lens concave toward the image and having at least one side as an aspherical surface; It provides a high-definition imaging optical system comprising a, satisfies the following conditional formula 1 with respect to the optical axis direction dimension of the optical system, and satisfies the following conditional formula 2-2 with respect to the refractive power of the first lens.

(Condition 1) 1.0 <TL / f <1.5

(Condition 2-2) 0.4 <f1 / f <0.9

Here, TL is the distance from the first lens object side surface of the first lens group to the image surface, f is the focal length of the entire optical system, and f1 is the focal length of the first lens.

Preferably, the following Conditional Expression 3-2 is satisfied with respect to the refractive power of the first and second lens groups.

(Condition 3-2) 1.1 <f12 / f <1.7

Here, f12 is a combined focal length of the first lens group and the second lens group.

And this invention is aperture diaphragm in order from an object side; A first lens group having a first lens having both convex surfaces and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And a fourth lens group having a negative refractive power by having a fifth lens concave toward the image and having at least one side as an aspherical surface; It provides a high-definition imaging optical system, characterized in that it satisfies the following conditional formula 1 with respect to the optical axis direction dimensions of the optical system.

(Condition 1) 1.0 <TL / f <1.5

Here, TL is the distance from the first lens object side surface of the first lens group to the image surface, and f is the focal length of the entire optical system.

Preferably, the second lens group includes a second lens having a positive refractive power and a third lens having a negative refractive power.

Preferably, the second lens group includes a second lens having a negative refractive power and a third lens having a positive refractive power.

More preferably, the fifth lens of the fourth lens group has a curved point on the image side surface.

In addition, the present invention is an aperture stop in order from the object side; A first lens group having a first lens having both convex surfaces and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group which is convex toward the image and has a fourth lens having at least one side as an aspherical surface and having a positive refractive power; And a fourth lens group having a negative refractive power, the fifth lens being concave toward the image and having at least one side as an aspheric surface; It provides a high-definition imaging optical system comprising a.

Preferably, the second lens group includes a second lens having a positive refractive power and a third lens having a negative refractive power.

Preferably, the second lens group includes a second lens having a negative refractive power and a third lens having a positive refractive power.

More preferably, the fifth lens of the fourth lens group is provided in a cross-sectional shape in which the image-side surface is convex toward the object side and convex to the image-side surface as the distance from the optical axis.

According to the present invention having the above-described configuration, there is an effect that a compact and high-definition optical system can be obtained with high resolution and a small number of lenses.

Further, by correcting the chromatic aberration while improving the resolution, the color fringing phenomenon can be satisfactorily improved in indoor or outdoor photography, thereby improving quality and reliability.

In addition, by using a lens made of a plastic material, not only can be reduced in weight, but also has an advantageous effect that an optical system can be implemented, which is easy to manufacture, which enables mass production and low manufacturing cost.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29 and 31 show the first to sixteenth embodiments of the high-definition imaging optical system according to the present invention. It is a lens block diagram. In the following lens configuration, the thickness, size, and shape of the lens have been somewhat exaggerated for explanation, and in particular, the shape of the spherical or aspherical surface shown in the lens configuration is merely an example and is not limited thereto.

1,3,5,7,9,11,13,15,17,19,21,23,25,27,29 and 31, the embodiment of the present invention is located closest to the object side. An aperture diaphragm S for removing unnecessary light is disposed, and then, in order from the object side, the first lens group G1, the second lens group G2, the third lens group G3, and the fourth lens group. (G4).

The first lens group G1 may include a first lens L1, and the first lens L1 may have an object side surface 1 convex toward the object side or both sides 1 and 2 convex. Has refractive power.

The second lens group G2 has negative refractive power as a whole, and includes a second lens L2 and a third lens L3 in which the image side surface 4 and the object side that face each other are bonded or separated from each other.

The second lens L2 has a positive refractive power in which the image side surface 4 is convex toward the image side, and the third lens L3 has a negative refractive power in which the object side surface is concave toward the image side. The three lenses are shown to be bonded as shown in Figs. 1, 3, 5, 7, 9, 11, 13, 15, 17, and 19, but are not limited thereto, and as shown in Figs. It may be separated.

25, 27, 29 and 31, the second lens L2 has negative refractive power in which the image side surface 4 is concave to the image side, and the third lens L3 has the object side surface. The second lens L2 and the third lens L3 have a convex amount of refractive power toward the object side, and the second lens L2 and the third lens L3 are illustrated and described as being bonded, but the present invention is not limited thereto, and the same may be separated from each other.

The third lens group G3 includes a fourth lens L4, and the fourth lens L4 has an image surface 7 convex toward the image side and has a positive refractive power.

The fourth lens group G4 includes a fifth lens L5, and the fifth lens L5 has negative refractive power.

Herein, at least one of the object-side surfaces 6 and 8 and the image-side surfaces 7 and 9 may be provided as an aspheric surface of the fourth lens L4 and the fifth lens L5.

 In addition, by constructing two or more of the plurality of lenses provided in the first lens group G1 to the fourth lens group G4 with plastic lenses, the manufacturing cost is low, mass production is possible, and a compact and lightweight optical system can be realized. There is an advantage.

In addition, since the at least one surface of the fourth and fifth lenses L4 and L5 is aspheric, the optical system can be miniaturized compared to the spherical lens.

In addition, the fifth lens L5 of the fourth lens group G4 is provided with a cross section in which the image side surface 9 is convex toward the object side and convex toward the image as the image surface 9 moves away from the optical axis toward the periphery thereof. A curved point is formed on the upper surface 9 of the c).

The infrared filter IF is provided behind the fourth lens group G4. The infrared filter IF may be replaced or omitted with other filters as necessary, and shall not affect the optical properties of the present invention in principle.

In addition, the image sensor is composed of a Charged Coupled Device (CCD), a Complementarly Metal Oxide Semiconductor (CMOS), etc., and is provided on an upper surface (photosensitive surface) 12 for receiving an image formed by the lens. Correspondingly arranged behind the infrared filter IF.

Look at the effect of the following Conditional Expressions 1 to 6-2 under such an overall configuration.

(Condition 1) 1.0 <TL / f <1.5

Here, TL is the distance from the object-side surface 1 of the first lens L1 to the image surface 12 of the first lens group G1.

Conditional Expression 1 is to reduce the overall length of the optical system while satisfying the high resolution, and when it is out of the lower limit, coma and astigmatism are largely generated, so that it is difficult to obtain a clear image, and the optimal top position of the screen center and surroundings is greatly increased. This makes it impossible to achieve high resolution across the screen. In addition, the pads synthesizing (Petzval) Sum) is increased, the upper surface curvature is increased. If the upper limit is out of the upper limit, the distance from the object-side surface 1 of the first lens L1 to the image surface 12 becomes long, which makes it difficult to design a compact optical system.

(Condition 2-1) 0.5 <f1 / f <1.0

(Condition 2-2) 0.4 <f1 / f <0.9

Here, f1 is the focal length of the first lens group G1.

Conditional Expressions 2-1 and 2-2 are to ensure excellent image quality by suppressing spherical aberration and coma flare while keeping the refractive power of the first lens group and the overall size of the optical system small. Spherical aberration and coma aberration are greatly generated, resulting in deterioration of image quality. And, if the deviation from the upper limit, the refractive power of the first lens (L1) is weakened, so that the store location where the light rays starting from the object-side surface (1) of the first lens (L1) meets the optical axis is far away. It becomes difficult to get

(Condition 3-1) 1.1 <f12 / f <1.5

(Condition 3-2) 1.1 <f12 / f <1.7

Here, f12 is the combined focal length of the first lens group G1 and the second lens group G2.

Condition Equation 3-1 and Condition Equation 3-2 relate to the refractive power of the first and second lens groups G1 and G2, and the overall size of the optical system is minimized while suppressing the occurrence of color fringing that may affect the image quality. In order to keep the size small, if the deviation is lower than the lower limit, the image point position of each wavelength of the light beam incident toward one point of the image surface is greatly shifted, resulting in color bleeding, thereby degrading image quality. Let's do it. And, if the deviation from the upper limit, the force to refract the incident light flux is weakened, the distance from the object-side surface 1 of the first lens group G1 to the image surface 12 becomes long, so that the compact optical system It becomes difficult to get

(Condition 4-1) -2.5 <R_L4F / f <-1.0

(Condition 4-2) -3.0 <R_L4F / f <0.0

Here, R_L4F is the radius of curvature of the object-side surface 6 of the fourth lens L4.

Conditional Expression 4-1 and Conditional Expression 4-2 relate to the shape of the fourth lens L1 and to reduce the overall size of the optical system while minimizing the shape distortion of the subject. The aberration becomes very large. If it is out of the upper limit, the distortion aberration can be made very small, but the shop position is moved backwards, so that the distance from the object side surface 1 of the first lens L1 to the image surface 12 becomes farther, and thus the length of the entire photographing lens system Becomes large.

(Condition 5-1) 45 <V_L2 <71

(Condition 5-2) 23 <V_L3 <40

(Condition 5-3) 50 <V_L1 <70

(Condition 5-4) 25 <V_L2 <45

(Condition 5-5) 50 <V_L3 <70

Here, V_L1 is the Abbe number of the first lens, V_L2 is the Abbe number of the second lens, and V_L3 is the Abbe number of the third lens.

Conditional Expression 5-1, Conditional Expression 5-2, Conditional Expression 5-3, Conditional Expression 5-4 and Conditional Expression 5-5 relate to Abbe numbers of the first, second and third lenses L1, L2 and L3. Then, chromatic aberration generated in the second lens L2 having positive refractive power can be appropriately corrected by the third lens L3 having negative refractive power.

(Condition 6-1) -1.4 <f3 / f4 <-0.8

(Condition 6-2) -1.4 <f3 / f4 <-0.7

Here, f3 'is the focal length of the third lens group G3, and f4' is the focal length of the fourth lens group G4.

Conditional Expressions 6-1 and 6-2 relate to the angle of the chief ray angle incident on the upper surface 12. In the optical system using an image sensor such as a CMOS or CCD, imaging of the image sensor to obtain good light sensitivity is achieved. By properly arranging the micro lens array on the surface, the incident angle of the chief rays of light is increased, whereby the chief ray incident angle of the image sensor with good light sensitivity is determined.

Therefore, if the conditional expressions 6-1 and 6-2 are out of the range, the light receiving sensitivity of the image sensor may deteriorate sharply, resulting in deterioration or darkening of the image quality.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

The aspherical surface used in each of the following examples is obtained from well-known Equation 1, and is used for the Conic constant (K) and the aspherical coefficients (A, B, C, D, and E), followed by the numerals. 'Represents a power of 10. For example, E21 has a 10 ^21, E-02 indicates the ^10-2.

Z (r): Distance from the vertex of the lens to the optical axis direction

r: distance in the direction perpendicular to the optical axis

c: radius of curvature at the vertex of the lens

K: Conic constant

A, B, C, D, E, F: Aspherical Coefficient

Example 1

Table 1 below shows numerical examples according to the first embodiment of the present invention.

1 is a lens configuration diagram illustrating a high-definition imaging optical system according to a first embodiment of the present invention, and FIGS. 2A to 2C show aberrations of the optical systems shown in Table 1 and FIG. 1.

In addition, the d line shown in the spherical aberration diagram below shows a 587.56 nm wavelength, the g line shows a 435.83 nm wavelength, the c line shows 656.27 nm, and S.C is a sine condition. In the astigmatism diagram, "S" represents sagittal and "M" represents tangential.

In Example 1, the effective focal length f of the entire lens system is 5.686 mm, the F number F _No is 2.8, and the total angle of the lens (2ω) is 64 °. The total length TL from the object-side surface of the first lens group to the image surface is 6.50 mm.

The focal length f1 of the first lens group G1 is 3.74 mm, the focal length f2 of the second lens group G2 is -5.238 mm, and the focal length f3 of the third lens group G3 is 3.735. mm, and the focal length f4 of the fourth lens group G4 is −3.169 mm.

In Table 1, * denotes an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 2 below.

Example 2

Table 3 below shows a numerical example according to the second embodiment of the present invention.

4 is a lens configuration diagram showing a high-definition imaging optical system according to a second embodiment of the present invention, and FIGS. 4A to 4C show aberrations of the optical systems shown in Tables 3 and 3.

In Example 2, the effective focal length f of the optical system is 5.683 mm, the F number F _No is 2.8, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 6.50 mm.

The focal length f1 of the first lens group G1 is 3.651 mm, the focal length f2 of the second lens group G2 is -5.538 mm, and the focal length f3 of the third lens group G3 is 4.070. mm, and the focal length f4 of the fourth lens group G4 is −3.523 mm.

In Table 3, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 4 below.

Example 3

Table 5 below shows a numerical example according to the third embodiment of the present invention.

6 is a lens configuration diagram illustrating a high-definition imaging optical system according to a third embodiment of the present invention, and FIGS. 6A to 6C show aberrations of the optical systems shown in Tables 5 and 5.

In Example 3, the effective focal length f of the optical system is 5.699 mm, the F number F _No is 2.8, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 6.80 mm.

The focal length f1 of the first lens group G1 is 3.554 mm, the focal length f2 of the second lens group G2 is -5.029 mm, and the focal length f3 of the third lens group G3 is 2.776. mm, and the focal length f4 of the fourth lens group G4 is -2.646 mm.

In Table 5, * represents an aspherical surface, and the values of the koenic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 6 below.

Example 4

Table 7 below shows numerical examples according to the fourth embodiment of the present invention.

7 is a lens configuration diagram showing a high-definition imaging optical system according to a fourth embodiment of the present invention, and FIGS. 8A to 8C show aberrations of the optical systems shown in Tables 7 and 7.

In Example 4, the effective focal length f of the optical system is 5.700 mm, the F number F _No is 2.8, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 6.80 mm.

The focal length f1 of the first lens group G1 is 3.430 mm, the focal length f2 of the second lens group G2 is -4.851 mm, and the focal length f3 of the third lens group G3 is 2.714. mm, and the focal length f4 of the fourth lens group G4 is -2.545 mm.

In Table 7, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 8 below.

Example 5

Table 9 below shows a numerical example according to the fifth embodiment of the present invention.

9 is a lens configuration diagram illustrating a high-definition imaging optical system according to a fifth embodiment of the present invention, and FIGS. 10A to 10C show aberrations of the optical systems shown in Tables 9 and 9.

In Example 5, the effective focal length f of the optical system is 5.706 mm, the F number F _No is 2.6, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.15 mm.

The focal length f1 of the first lens group G1 is 3.551 mm, the focal length f2 of the second lens group G2 is -5.332 mm, and the focal length f3 of the third lens group G3 is 2.311. mm, and the focal length f4 of the fourth lens group G4 is -2.195 mm.

In Table 9, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 10 below.

Example 6

Table 11 below shows a numerical example according to the sixth embodiment of the present invention.

11 is a lens configuration diagram showing a high-definition imaging optical system according to a sixth embodiment of the present invention, and FIGS. 12A to 12C show aberrations of the optical systems shown in Tables 11 and 11.

In Example 6, the effective focal length f of the optical system was 5.691 mm, the F number F _No was 2.6, and the total angle 2ω of the lens was 64 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.15 mm.

The focal length f1 of the first lens group G1 is 3.586 mm, the focal length f2 of the second lens group G2 is -5.274 mm, and the focal length f3 of the third lens group G3 is 2.697. mm, and the focal length f4 of the fourth lens group G4 is -2.608 mm.

In Table 11, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 12 below.

Example 7

Table 13 below shows a numerical example according to the seventh embodiment of the present invention.

13 is a lens configuration diagram showing a high-definition imaging optical system according to a seventh embodiment of the present invention, and FIGS. 14A to 14C show aberrations of the optical systems shown in Tables 13 and 13.

In Example 7, the effective focal length f of the optical system is 5.698 mm, the F number F _No is 2.6, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 7.58 mm.

The focal length f1 of the first lens group G1 is 4.434 mm, the focal length f2 of the second lens group G2 is -7.478 mm, and the focal length f3 of the third lens group G3 is 2.652. mm, and the focal length f4 of the fourth lens group G4 is -2.599 mm.

In Table 13, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 14 below.

Example 8

Table 15 below shows numerical examples according to the eighth embodiment of the present invention.

15 is a lens configuration diagram illustrating a high-definition imaging optical system according to an eighth embodiment of the present invention, and FIGS. 16A to 16C show aberrations of the optical systems shown in Tables 15 and 15.

In Example 8, the effective focal length f of the optical system is 5.702 mm, the F number F _No is 2.6, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 7.58 mm.

The focal length f1 of the first lens group G1 is 4.460 mm, the focal length f2 of the second lens group G2 is -7.334 mm, and the focal length f3 of the third lens group G3 is 2.612. mm, and the focal length f4 of the fourth lens group G4 is -2.554 mm.

In Table 15, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 16 below.

Example 9

Table 17 below shows a numerical example according to the ninth embodiment of the present invention.

17 is a lens configuration diagram illustrating a high-definition imaging optical system according to a ninth embodiment of the present invention, and FIGS. 18A to 18C show aberrations of the optical systems shown in Table 17 and FIG. 17.

In Example 9, the effective focal length f of the optical system is 5.701 mm, the F number F _No is 2.6, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.92 mm.

The focal length f1 of the first lens group G1 is 4.972 mm, the focal length f2 of the second lens group G2 is -9.728 mm, and the focal length f3 of the third lens group G3 is 2.706. mm, and the focal length f4 of the fourth lens group G4 is -2.624 mm.

In Table 17, * represents an aspherical surface, and the values of the koenic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 18 below.

Example 10

Table 19 below shows a numerical example according to the tenth embodiment of the present invention.

20 is a lens configuration diagram illustrating a high-definition imaging optical system according to a tenth embodiment of the present invention, and FIGS. 20A to 20C show aberrations of the optical systems shown in Table 19 and FIG. 19.

In Example 10, the effective focal length f of the optical system is 5.698 mm, the F number F _No is 2.6, and the total angle 2ω of the lens is 64 °. The total length TL from the object-side surface to the image surface of one lens group is 7.94 mm.

The focal length f1 of the first lens group G1 is 4.606 mm, the focal length f2 of the second lens group G2 is -7.395 mm, and the focal length f3 of the third lens group G3 is 2.504. mm, and the focal length f4 of the fourth lens group G4 is -2.443 mm.

In Table 19, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 20 below.

Example 11

Table 21 below shows a numerical example according to the eleventh embodiment of the present invention.

21 is a lens configuration diagram illustrating a high-definition imaging optical system according to an eleventh embodiment of the present invention, and FIGS. 22A to 22C show aberrations of the optical systems shown in Table 21 and FIG. 21.

In Example 11, the effective focal length f of the optical system was 5.703 mm, the F number F _No was 2.6, and the total angle 2ω of the lens was 64 °. The total length TL from the object-side surface to the image surface of one lens group is 7.20 mm.

The focal length f1 of the first lens group G1 is 3.849 mm, the focal length f2 of the second lens group G2 is -5.925 mm, and the focal length f3 of the third lens group G3 is 2.272. mm, the focal length f4 of the fourth lens group G4 is -2.202 mm.

In Table 21, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 22 below.

Example 12

Table 23 below shows a numerical example according to the twelfth embodiment of the present invention.

23 is a lens configuration diagram showing a high-definition imaging optical system according to a twelfth embodiment of the present invention, and FIGS. 24A to 24C show aberrations of the optical systems shown in Tables 23 and 23. FIG.

In Example 12, the effective focal length f of the optical system was 5.703 mm, the F number F _No was 2.6, and the total angle 2ω of the lens was 64 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.57 mm.

The focal length f1 of the first lens group G1 is 4.570 mm, the focal length f2 of the second lens group G2 is -7.384 mm, and the focal length f3 of the third lens group G3 is 2.713. mm, the focal length f4 of the fourth lens group G4 is -2.730 mm.

In Table 23, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 24 below.

Example 13

Table 25 below shows numerical examples according to Example 13 of the present invention.

25 is a lens configuration diagram showing a high-definition imaging optical system according to a thirteenth embodiment of the present invention, and FIGS. 26A to 26C show aberrations of the optical systems shown in Table 25 and FIG. 25.

In Example 13, the effective focal length f of the optical system was 5.625 mm, the F number F _No was 2.8, the total angle of the lens 2ω was 64.6 °, and The total length TL from the object-side surface to the image surface of one lens group is 7.26 mm.

The focal length f1 of the first lens group G1 is 3.662 mm, the focal length f2 of the second lens group G2 is -5.031 mm, and the focal length f3 of the third lens group G3 is 2.857. mm, the focal length f4 of the fourth lens group G4 is -2.760 mm.

In Table 25, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 26 below.

Example 14

Table 27 below shows a numerical example according to the fourteenth embodiment of the present invention.

27 is a lens configuration diagram showing a high-definition imaging optical system according to a fourteenth embodiment of the present invention, and FIGS. 28A to 28C show aberrations of the optical systems shown in Tables 27 and 27. FIG.

In Example 14, the effective focal length f of the optical system was 5.637 mm, the F number F _No was 2.8, and the total angle 2ω of the lens was 64.6 °. The total length TL from the object-side surface to the image surface of one lens group is 7.19 mm.

The focal length f1 of the first lens group G1 is 3.508 mm, the focal length f2 of the second lens group G2 is -4.394 mm, and the focal length f3 of the third lens group G3 is 2.272. mm, the focal length f4 of the fourth lens group G4 is -2.186 mm.

In Table 27, * represents an aspherical surface, and the values of the koenic constant (K) and the aspherical coefficients (A, B, C, D, E, F) according to Equation 1 are shown in Table 28 below.

Example 15

Table 29 below shows a numerical example according to the fifteenth embodiment of the present invention.

29 is a lens configuration diagram illustrating a high-definition imaging optical system according to a fifteenth embodiment of the present invention, and FIGS. 30A to 30C show aberrations of the optical systems shown in Table 29 and FIG. 29.

In Example 15, the effective focal length f of the optical system was 5.624 mm, the F number F _No was 2.8, and the total angle 2ω of the lens was 64.6 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.10 mm.

The focal length f1 of the first lens group G1 is 3.488 mm, the focal length f2 of the second lens group G2 is -4.582 mm, and the focal length f3 of the third lens group G3 is 2.612. mm, the focal length f4 of the fourth lens group G4 is -2.475 mm.

In Table 29, * represents an aspherical surface, and the values of the koenic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 30 below.

Example 16

Table 31 below shows a numerical example according to the sixteenth embodiment of the present invention.

31 is a lens configuration diagram showing a high-definition imaging optical system according to a sixteenth embodiment of the present invention, and FIGS. 32A to 32C show aberrations of the optical systems shown in Table 31 and FIG.

In Example 16, the effective focal length f of the optical system was 5.628 mm, the F number F _No was 2.8, and the total angle 2ω of the lens was 64.6 °. The total length TL from the object-side surface of the one lens group to the image surface is 7.0 mm.

The focal length f1 of the first lens group G1 is 3.539 mm, the focal length f2 of the second lens group G2 is -4.745 mm, and the focal length f3 of the third lens group G3 is 2.641. mm, the focal length f4 of the fourth lens group G4 is -2.309 mm.

In Table 31, * represents an aspherical surface, and the values of the conic constant (K) and aspherical coefficients (A, B, C, D, E, and F) according to Equation 1 are shown in Table 32 below.

The values of Conditional Expressions 1 to 6-1 for Examples 1 to 12 are shown in Table 33 below.

In addition, the values of Conditional Expressions 1 and 2-2 to 6-2 for Examples 13 to 16 are shown in Table 34 below.

As shown in Table 21, Examples 1 to 16 of the present invention satisfy conditional expressions 1 to 6-2, and FIGS. 2, 4, 6, 8, 10, 12, 14, and 16. 18 and 20, 22, 24, 26, 28, 30 and 32, it can be seen that an optical system having excellent characteristics of the first aberration is implemented.

1 is a lens configuration showing a high-definition imaging optical system according to a first embodiment of the present invention.

2A to 2C are graphs illustrating aberrations of the optical system illustrated in FIG. 1.

3 is a lens configuration diagram showing a high-definition imaging optical system according to a second embodiment of the present invention.

4A to 4C are graphs showing aberrations of the optical system illustrated in FIG. 3.

5 is a lens diagram illustrating a high-definition imaging optical system according to a third embodiment of the present invention.

6A to 6C are graphs illustrating aberrations of the optical system illustrated in FIG. 5.

7 is a lens diagram illustrating a high-definition imaging optical system according to a fourth embodiment of the present invention.

8A to 8C are graphs illustrating aberrations of the optical system illustrated in FIG. 7.

9 is a lens diagram illustrating a high-definition imaging optical system according to a fifth embodiment of the present invention.

10A to 10C are graphs illustrating aberrations of the optical system illustrated in FIG. 9.

11 is a lens diagram illustrating a high-definition imaging optical system according to a sixth embodiment of the present invention.

12A to 12C are graphs illustrating aberrations of the optical system illustrated in FIG. 11.

13 is a lens configuration diagram illustrating a high-definition imaging optical system according to a seventh embodiment of the present invention.

14A to 14C are graphs showing aberrations of the optical system shown in FIG. 13.

15 is a lens configuration diagram illustrating a high-definition imaging optical system according to an eighth embodiment of the present invention.

16A to 16C are graphs showing aberrations of the optical system shown in FIG. 15.

17 is a lens diagram illustrating a high-definition imaging optical system according to a ninth embodiment of the present invention.

18A to 18C are graphs showing aberrations of the optical system shown in FIG. 17.

19 is a lens diagram illustrating a high-definition imaging optical system according to a tenth embodiment of the present invention.

20A to 20C are graphs illustrating aberrations of the optical system illustrated in FIG. 19.

21 is a lens diagram illustrating a high-definition imaging optical system according to an eleventh embodiment of the present invention.

22A to 22C are graphs showing aberrations of the optical system shown in FIG. 21.

Fig. 23 is a lens configuration diagram showing a high definition imaging optical system according to a twelfth embodiment of the present invention.

24A to 24C are graphs illustrating aberrations of the optical system illustrated in FIG. 23.

25 is a lens configuration diagram illustrating a high-definition imaging optical system according to a thirteenth embodiment of the present invention.

26A to 26C are graphs illustrating aberrations of the optical system illustrated in FIG. 25.

27 is a lens configuration diagram showing a high-definition imaging optical system according to a fourteenth embodiment of the present invention.

28A to 28C are graphs showing aberrations of the optical system shown in FIG. 27.

29 is a lens configuration diagram illustrating a high definition imaging optical system according to a fifteenth embodiment of the present invention.

30A to 30C are graphs showing aberrations of the optical system shown in FIG. 29.

31 is a lens configuration diagram illustrating a high definition imaging optical system according to a sixteenth embodiment of the present invention.

32A to 32C are graphs showing aberrations of the optical system shown in FIG. 31.

Explanation of symbols on the main parts of the drawings

G1: first lens group G2: second lens group

G2: second lens group G4: fourth lens group

L1: first lens L2: second lens

L3: third lens L4: fourth lens

L5: 5th lens S ...

Claims (29)

Aperture stop in sequence from the object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And A fourth lens group having a fifth lens concave toward the image and having negative refractive power; High-definition imaging optical system comprising a. The high-definition imaging optical system of claim 1, wherein the second lens group comprises a second lens having positive refractive power and a third lens having negative refractive power. The high-definition imaging optical system of claim 2, wherein at least one surface of the fourth lens and the fifth lens is provided in an aspheric shape. 4. The high-definition imaging optical system according to claim 3, wherein the following Conditional Expression 1 is satisfied with respect to the optical axis direction dimension of the optical system. (Condition 1) 1.0 <TL / f <1.5 TL: distance from the side of the first lens object of the first lens group to the image surface f: focal length of the whole optical system 4. The high-definition imaging optical system according to claim 3, wherein the following conditional expression 2-1 is satisfied with respect to the refractive power of the first lens group. (Condition 2-1) 0.5 <f1 / f <1.0 Where f1 is the focal length of the first lens group. 4. The high-definition imaging optical system according to claim 3, wherein the following conditional expression 3-1 is satisfied with respect to the refractive power of the first and second lens groups. (Condition 3-1) 1.1 <f12 / f <1.5 Where f12 is the combined focal length of the first lens group and the second lens group. 4. The high-definition imaging optical system according to claim 3, wherein the following conditional expression 4-1 is satisfied with respect to the shape of the fourth lens. (Condition 4-1) -2.5 <R_L4F / f <-1.0 Where R_L4F is the radius of curvature of the object-side surface of the fourth lens. 4. The high-definition imaging optical system according to claim 3, wherein the following conditional expressions 5-1 and 5-2 are satisfied with respect to the Abbe number of the second and third lenses. (Condition 5-1) 45 <V_L2 <71 (Condition 5-2) 23 <V_L3 <40 Where V_L2 is the Abbe number of the second lens. V_L3: Abbe number of the third lens 4. The high-definition imaging optical system according to claim 3, wherein the following conditional expression 6-1 is satisfied with respect to the refractive power of the first lens group and the fourth lens group. (Condition 6-1) -1.4 <f3 / f4 <-0.8 Where f3 is the focal length of the first lens group. f4: The focal length of the fourth lens group The high-definition imaging optical system of claim 1, wherein the second lens group comprises a second lens having negative refractive power and a third lens having positive refractive power. 11. The high definition imaging optical system of claim 10, wherein at least one surface of the fourth lens and the fifth lens has an aspherical surface shape. 12. The high-definition imaging optical system according to claim 11, wherein the following Conditional Expression 1 is satisfied with respect to the optical axis direction dimension of the optical system. (Condition 1) 1.0 <TL / f <1.5 TL: distance from the side of the first lens object of the first lens group to the image surface f: focal length of the whole optical system 12. The high-definition imaging optical system according to claim 11, wherein the following conditional expression 2-2 is satisfied with respect to the refractive power of the first lens group. (Condition 2-2) 0.4 <f1 / f <0.9 Where f1 is the focal length of the first lens group. 12. The high-definition imaging optical system according to claim 11, wherein the following Conditional Expression 3-2 is satisfied with respect to the refractive power of the first and second lens groups. (Condition 3-2) 1.1 <f12 / f <1.7 Where f12 is the combined focal length of the first lens group and the second lens group. 12. The high-definition imaging optical system according to claim 11, wherein the following conditional expression 4-2 is satisfied with respect to the shape of the fourth lens. (Condition 4-1) -3.0 <R_L4F / f <-0.0 Where R_L4F is the radius of curvature of the object-side surface of the fourth lens. 12. The high-definition imaging optical system according to claim 11, wherein the following conditional expressions 5-3, 5-4, and 5-5 are satisfied with respect to the Abbe number of the first, second, and third lenses. (Condition 5-3) 50 <V_L1 <70 (Condition 5-4) 25 <V_L2 <45 (Condition 5-5) 50 <V_L3 <70 Where V_L1 is the Abbe number of the first lens. V_L2: Abbe number of the second lens V_L3: Abbe number of the third lens 12. The high-definition imaging optical system according to claim 11, wherein the following conditional expression 6-1 is satisfied with respect to the refractive power of the first lens group and the fourth lens group. (Condition 6-2) -1.4 <f3 / f4 <-0.7 Where f3 is the focal length of the first lens group. f4: The focal length of the fourth lens group Aperture stop in sequence from the object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group in which the image side surface of the second lens having positive refractive power and the object side surface of the third lens having negative refractive power are bonded or separated from each other and have negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And A fourth lens group having a negative refractive power with a fifth lens concave toward the image and having at least one side as an aspherical surface; Including, A high definition imaging optical system characterized by satisfying the following Conditional Expression 1 with respect to the optical axis direction dimension of the optical system and satisfying the following Conditional Expression 2-1 with respect to the refractive power of the first lens. (Condition 1) 1.0 <TL / f <1.5 (Condition 2-1) 0.5 <f1 / f <1.0 TL: distance from the first lens object side surface of the first lens group to the image surface f: focal length of the whole optical system f1: The focal length of the first lens 19. The high-definition imaging optical system according to claim 18, wherein the following conditional expression 3-1 is satisfied with respect to the refractive power of the first and second lens groups. (Condition 3-1) 1.1 <f12 / f <1.5 Where f12 is the combined focal length of the first lens group and the second lens group. Aperture stop in sequence from the object side; A first lens group having a first lens convex toward the object side and having a positive refractive power; A second lens group in which an image side surface of the second lens having negative refractive power and an object side surface of the third lens having positive refractive power are bonded or separated from each other, and have negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And A fourth lens group having a negative refractive power with a fifth lens concave toward the image and having at least one side as an aspherical surface; Including, A high-definition imaging optical system according to claim 1, wherein the following Conditional Expression 1 is satisfied with respect to the optical axis direction of the optical system, and the following Conditional Expression 2-2 is satisfied with respect to the refractive power of the first lens. (Condition 1) 1.0 <TL / f <1.5 (Condition 2-2) 0.4 <f1 / f <0.9 TL: distance from the first lens object side surface of the first lens group to the image surface f: focal length of the whole optical system f1: The focal length of the first lens 21. The high-definition imaging optical system according to claim 20, wherein the following conditional formula 3-2 is satisfied with respect to the refractive power of the first and second lens groups. (Condition 3-2) 1.1 <f12 / f <1.7 Where f12 is the combined focal length of the first lens group and the second lens group. Aperture stop in sequence from the object side; A first lens group having a first lens having both convex surfaces and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group having a fourth lens convex toward the image and having a positive refractive power; And A fourth lens group having a negative refractive power with a fifth lens concave toward the image and having at least one side as an aspherical surface; Including, A high-definition imaging optical system characterized by satisfying the following conditional expression 1 with respect to the optical axis direction dimension of an optical system. (Condition 1) 1.0 <TL / f <1.5 TL: distance from the first lens object side surface of the first lens group to the image surface f: focal length of the whole optical system 23. The high definition imaging optical system of claim 22, wherein the second lens group comprises a second lens having positive refractive power and a third lens having negative refractive power. 23. The high definition imaging optical system of claim 22, wherein the second lens group comprises a second lens having negative refractive power and a third lens having positive refractive power. 25. The high-definition imaging optical system according to any one of claims 22 to 24, wherein the fifth lens of the fourth lens group has a curved point on an image side surface. Aperture stop in sequence from the object side; A first lens group having a first lens having both convex surfaces and having a positive refractive power; A second lens group having a second negative lens and a third lens having an image side and an object side facing each other joined or separated from each other and having negative refractive power as a whole; A third lens group which is convex toward the image and has a fourth lens having at least one side as an aspherical surface and having a positive refractive power; And A fourth lens group having a negative refractive power with a fifth lens concave to the image side and having at least one side as an aspherical surface; High-definition imaging optical system comprising a. 27. The high definition imaging optical system of claim 26, wherein the second lens group comprises a second lens having positive refractive power and a third lens having negative refractive power. 27. The high definition imaging optical system of claim 26, wherein the second lens group comprises a second lens having negative refractive power and a third lens having positive refractive power. 29. The high-definition imaging method according to any one of claims 26 to 28, wherein the fifth lens of the fourth lens group is provided in a cross section in which the image side surface is convex toward the object side and convex toward the image side surface as the image side surface moves away from the optical axis. Optical system.

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