KR20230040852A - Imaging Lens System - Google Patents

Abstract

An imaging optical system according to an embodiment of the present invention includes: a first lens group; a first optical path changing means including a plurality of reflective surfaces; and a second optical path changing means including a plurality of reflective surfaces. In the imaging optical system according to an embodiment, the first lens group, the first optical path changing means, and the second optical path changing means are sequentially disposed from an object side. The imaging optical system according to an embodiment has a long focal length and can be mounted on a small terminal or a thin terminal.

Description

Imaging optical system {Imaging Lens System}

The present invention relates to an imaging optical system having a long focal length.

An imaging optical system having a long focal length (eg, a telescopic imaging optical system) is difficult to mount in a small terminal because it is not easy to reduce the thickness and size of the optical system. However, as the demand for function improvement and performance improvement of a small terminal, for example, a smart phone, increases, the need to mount a telescopic imaging optical system to the small terminal is increasing.

An object of the present invention is to provide an imaging optical system having a long focal length while being able to be installed in a small terminal.

An imaging optical system according to an embodiment of the present invention for achieving the above object includes a first lens group; first optical path changing means including a plurality of reflecting surfaces; and a second optical path conversion unit including a plurality of reflective surfaces. In the imaging optical system according to an embodiment, the first lens group, the first optical path changing means, and the second optical path changing means are sequentially disposed from the object side. An imaging optical system according to an embodiment has a long focal length and can be mounted on a small terminal or a thin terminal.

The imaging optical system according to the present invention has a long focal length and can be mounted on a small terminal or a thin terminal.

1 is a configuration diagram of an imaging optical system according to a first embodiment.
2 is an aberration curve of the imaging optical system shown in FIG. 1;
FIG. 3 is a first modified example of the imaging optical system shown in FIG. 1 .
FIG. 4 is a second modified example of the imaging optical system shown in FIG. 1 .
FIG. 5 is a third modified example of the imaging optical system shown in FIG. 1 .
FIG. 6 is a fourth modified example of the imaging optical system shown in FIG. 1 .
FIG. 7 is a fifth modified example of the imaging optical system shown in FIG. 1 .
8 is a configuration diagram of an imaging optical system according to a second embodiment.
9 is an aberration curve of the imaging optical system shown in FIG. 8;
FIG. 10 is a modified example of the imaging optical system shown in FIG. 8 .
11 is a configuration diagram of an imaging optical system according to a third embodiment.
FIG. 12 is an aberration curve of the imaging optical system shown in FIG. 11;
FIG. 13 is a first modified example of the imaging optical system shown in FIG. 11 .
FIG. 14 is a second modified example of the imaging optical system shown in FIG. 11 .
15 is a configuration diagram of an imaging optical system according to a fourth embodiment.
16 is an aberration curve of the imaging optical system shown in FIG. 15;
17 is a configuration diagram of an imaging optical system according to a fifth embodiment.
18 is an aberration curve of the imaging optical system shown in FIG. 17;
19 is a configuration diagram of an imaging optical system according to a sixth embodiment.
20 is an aberration curve of the imaging optical system shown in FIG. 19;
21 is a configuration diagram of an imaging optical system according to a seventh embodiment.
FIG. 22 is an aberration curve of the imaging optical system shown in FIG. 21;
23 is a configuration diagram of an imaging optical system according to an eighth embodiment.
24 is an aberration curve of the imaging optical system shown in FIG. 23;

In describing the present invention below, terms referring to the components of the present invention are named in consideration of the functions of each component, so they should not be understood as limiting the technical components of the present invention.

In addition, throughout the specification, that a component is 'connected' to another component includes not only the case where these components are 'directly connected', but also the case where they are 'indirectly connected' through other components. means that In addition, 'including' a certain component means that other components may be further included, rather than excluding other components unless otherwise stated.

In this specification, the first lens means a lens closest to the object (or subject). In addition, the number of lenses means the order in which they are arranged along the optical axis direction from the object side. For example, the second lens means a lens positioned second from the object side, and the third lens means a lens positioned third from the object side. In this specification, the radius of curvature of the lens (Radius), thickness (Thickness), TTL (distance from the object side of the first lens to the image surface), 2ImgHT (diagonal length of the image surface), ImgHT (height of the image surface or 1/2 of 2ImgHT) , the unit of focal length is mm.

The thickness of the lens, the distance between the lenses, the TTL, and the angle of incidence are calculated sizes based on the optical axis of the imaging optical system. In addition, in the description of the shape of the lens, a convex shape on one surface means that a paraxial region of the corresponding surface is convex, and a concave shape means that the paraxial region of the corresponding surface is concave. Therefore, even if one surface of the lens is described as having a convex shape, the edge portion of the lens may be concave. Likewise, even if one surface of the lens is described as having a concave shape, the edge portion of the lens may be convex.

The imaging optical system described herein may be configured to be mounted on a portable electronic device. For example, the imaging optical system may be mounted on a smart phone, a laptop computer, an augmented reality device (VR), a virtual reality device (VR), a portable game machine, and the like. However, the use range and use examples of the imaging optical system described in this specification are not limited to the aforementioned electronic device. For example, the imaging optical system may be applied to an electronic device that provides a narrow mounting space but requires high-resolution imaging.

The imaging optical system described herein may be configured to reduce the external size of the imaging optical system while securing a long rear focal length (or BFL: distance from the image side surface of the rearmost lens to the image surface). For example, the imaging optical system can reduce the external size of the imaging optical system while securing a BFL necessary for realizing the telescopic imaging optical system through the reflector.

An imaging optical system according to the present specification may include a lens. In other words, the imaging optical system may include one or more lenses sequentially disposed along an optical axis. For example, the imaging optical system may include a first lens, a second lens, and a third lens sequentially disposed from the object side. However, the number of lenses constituting the imaging optical system is not limited to three. For example, the imaging optical system may include less than 3 lenses or may include 4 or more lenses.

The imaging optical system may be configured to form a long optical path in a limited space. For example, the reflector according to the present specification may be configured to reflect light twice or more.

An imaging optical system according to the present specification may include a plurality of reflectors. For example, the imaging optical system may include a first reflector and a second reflector disposed between the rearmost lens and the image surface. The first reflector and the second reflector may be sequentially disposed along the light path.

The first reflector and the second reflector according to the present specification may be configured to transmit and reflect light. For example, the first reflector is configured to reflect incident light three or more times and then refract it to the second reflector, and the second reflector reflects incident light two or more times and then irradiates it to the upper surface. It can be.

The first reflector and the second reflector according to the present specification may be configured to have a predetermined correlation. For example, the projection surface of the first reflector may be configured to be in equilibrium with the incident surface of the second reflector. As another example, the final reflection surface of the first reflector and the projection surface of the second reflector may be parallel or perpendicular to each other. As another example, the angle between the projection surface of the first reflector and the third reflection surface adjacent to the projection surface may be the same as the angle between the incident surface of the second reflector and the first reflection surface adjacent to the incident surface. there is.

For reference, in this specification, the reflector may be expressed in other terms. For example, the reflector may be expressed as an optical path changing unit or a prism.

An imaging optical system according to the first aspect may include a first lens group, first optical path changing means, and second optical path changing means sequentially disposed from the object side. The first optical path changing unit and the second optical path changing unit may include a plurality of reflecting surfaces. For example, the first optical path changing unit may include two reflecting surfaces, and the second optical path changing unit may include two reflecting surfaces. However, the number of reflection surfaces constituting the first optical path changing unit and the second optical path changing unit is not limited to two each. For example, the first optical path changing unit may include three reflecting surfaces, and the second optical path changing unit may include two reflecting surfaces. As another example, the first optical path changing unit may include two reflecting surfaces, and the second optical path changing unit may include three reflecting surfaces.

The imaging optical system according to the first aspect may be configured to satisfy a predetermined conditional expression. For example, in the imaging optical system according to the first aspect, the conditional expression 2.0 for TTL (the distance from the object side surface of the frontmost lens of the first lens group (ie, the first lens) to the image plane) and the focal length f1 of the frontmost lens < TTL/f1 < 4.0 may be satisfied.

In the first aspect, the first optical path changing means may include two reflecting surfaces as described above. As a specific example, the first optical path changing means reflects the light reflected from the first rearmost reflective surface and the first rearmost reflective surface disposed most adjacent to the second optical path changing means to the second optical path changing means. It may include a first reflective surface configured. The first rearmost reflective surface and the first reflective surface are disposed adjacent to each other in the first light path changing means, and may have a predetermined angle between them. For example, the first angle of intersection between the first rearmost reflective surface and the first reflective surface may be less than 45 degrees.

In the first aspect, the first optical path changing means may include three reflecting surfaces. For example, the first light path changing unit may further include a first frontmost reflective surface in addition to the first rearmost reflective surface and the first reflective surface. The first frontmost reflective surface may be configured to reflect light emitted from the first lens group to the first rearmost reflective surface.

In the first aspect, the second optical path changing means may include two or more reflecting surfaces as described above. As a specific example, the second optical path changing unit controls the light emitted from the second frontmost reflective surface and the first optical path changing unit (specifically, the first reflective surface) disposed most adjacent to the first optical path changing unit. 2 may include a second reflective surface configured to reflect to the frontmost reflective surface. The second frontmost reflective surface and the second reflective surface are disposed adjacent to each other in the second optical path changing means, and may have a predetermined angle between them. For example, the second intercept angle between the second frontmost reflective surface and the second reflective surface may be less than 45 degrees. As another example, the second interception angle may have substantially the same size as the first interception angle.

In the first aspect, the second optical path changing means may include three reflecting surfaces. For example, the second light path changing unit may further include a second rearmost reflective surface in addition to the second frontmost reflective surface and the second reflective surface. The second most rear reflective surface may be configured to reflect light emitted from the second most front reflective surface to an upper surface.

An imaging optical system according to the second aspect may include a lens group, first optical path converting means, and second optical path converting means sequentially disposed from the object side. The first optical path changing unit and the second optical path changing unit may include a total reflection surface. For example, the first optical path changing unit may include one total reflection surface, and the second optical path changing unit may include one total reflection surface.

The imaging optical system according to the third aspect may further include a lens configuration unique to the imaging optical system according to the first aspect or the second aspect. For example, in the imaging optical system according to the third aspect, the first lens group may include a lens having a positive refractive power. As another example, the first lens group may include a first lens having a positive refractive power and a second lens having a negative refractive power.

An imaging optical system according to a fourth aspect includes a first lens group, a first optical path changing means, a second lens group, a second optical path changing means, and a third optical path changing means sequentially disposed from the object side. can be configured. The imaging optical system according to the fourth aspect may include the features of the imaging optical systems according to the first to third aspects described above. For example, the second optical path changing means and the third optical path changing means of the fourth aspect are configured in the same or similar form as the first optical path changing means and the second optical path changing means according to the first to second aspects. It can be. As another example, the first lens group may have the same or similar shape as the first lens group according to the third aspect.

An imaging optical system according to the fifth aspect may be configured to satisfy at least one of the following conditional expressions. However, not only the imaging optical system according to the fifth aspect satisfies the following conditional expression. For example, the imaging optical systems according to the first to fourth aspects may satisfy at least one of the following conditional expressions.

BFL/TTL < 0.9

30 < V1-V2

18 mm < f

24 mm < TTL

1.1 < TTL/f

In the above conditional expression, BFL is the distance from the image side of the rearmost lens of the lens group to the image plane, TTL is the distance from the object side of the frontmost lens (first lens) of the lens group to the image plane, and V1 is the Abbe of the first lens. number, V2 is the Abbe number of the second lens (that is, the lens disposed most adjacent to the image side of the first lens), and f is the focal length of the imaging optical system.

The imaging optical system according to the fifth aspect may be configured to further satisfy at least one of the following conditional expressions.

0.6 < BFL/TTL < 0.9

32 < V1-V2 < 38

18 mm < f < 36 mm

24 mm < TTL < 42 mm

1.1 < TTL/f < 1.4

2.0 < TTL/f1 < 4.0

-5.0 < TTL/f2 < -0.2

-1.0 < TTL/f3 < 2.0

2.6 < f number < 4.0

2.0 < ( f number) *f/TTL < 3.4

0.16 < Vh1/TTL < 0.32

0.10 < Vh2/TTL < 0.23

In the above conditional expression, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, and Vh1 is the first half of the light path changing means from the object side of the first lens. is the distance to the slope (based on the optical axis), and Vh2 is the distance from the side surface of the object of the second lens to the first reflective surface of the optical path changing means (based on the optical axis).

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

First, an imaging optical system according to the first embodiment will be described with reference to FIG. 1 .

The imaging optical system 100 according to the present embodiment includes a lens group including a first lens 110, a second lens 120, and a third lens 130, a first reflector P1, and a second reflector ( P2) is included. However, the configuration of the imaging optical system 100 is not limited to the members described above. For example, the imaging optical system 100 may further include one or more lenses.

The first lens 110 to the third lens 130 may be sequentially disposed from the object side. For example, the second lens 120 may be disposed on the image side of the first lens 110, and the third lens 130 may be disposed on the image side of the second lens 120. The first lens 110 to the third lens 130 may be disposed at predetermined intervals. For example, the image side of the first lens 110 does not contact the object side of the second lens 120, and the image side of the second lens 120 does not contact the object side of the third lens 130. can be placed so as not to However, the first lens 110 to the third lens 130 are not necessarily arranged in a non-contact state. For example, the image side of the first lens 110 may contact the object side of the second lens 120 or the image side of the second lens 120 may contact the object side of the third lens 130. may be

Next, the characteristics of the first lens 110 to the third lens 130 will be described.

The first lens 110 has refractive power. For example, the first lens 110 may have positive refractive power. The first lens 110 may have a convex shape on one surface. For example, the first lens 110 may have a convex object side surface. One surface of the first lens 110 may have a concave shape. For example, the first lens 110 may have a concave image side surface. However, the image side of the first lens 110 is not limited to a concave shape. For example, an image side surface of the first lens 110 may have a convex shape if necessary. The first lens 110 may include a spherical surface. For example, both the object side and the image side of the first lens 110 may be formed as spherical surfaces.

The second lens 120 has refractive power. For example, the second lens 120 may have negative refractive power. The second lens 120 may have a convex shape on one surface. For example, the second lens 120 may have a convex object side surface. However, the object side of the second lens 120 is not limited to a convex shape. For example, the object side of the second lens 120 may have a concave shape as needed. The second lens 120 may have a concave shape on one surface. For example, the second lens 120 may have a concave image side surface. The second lens 120 may include an aspheric surface. For example, at least one of the object side and the image side of the second lens 120 may be formed as an aspheric surface.

The third lens 130 has refractive power. For example, the third lens 130 may have positive or negative refractive power. The third lens 130 may have a convex shape on one surface. For example, the third lens 130 may have a convex object side surface. The third lens 130 may have a concave shape on one surface. For example, the third lens 130 may have a concave image side surface. However, the image side of the third lens 130 is not limited to a concave shape. For example, an image side surface of the third lens 130 may have a convex shape if necessary. The third lens 130 may include an aspheric surface. For example, at least one of the object side and the image side of the third lens 130 may be formed as an aspheric surface.

The first reflector P1 and the second reflector P2 may be disposed between the third lens 130 and the image surface IP. The first reflector P1 and the second reflector P2 may be configured to reduce the external distance from the image side surface of the third lens 130 to the image surface IP. In other words, the first reflector P1 and the second reflector P2 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 130 to the image surface, and the third lens 130 The external distance or size from the image side surface of the lens 130 to the image surface may be reduced. Accordingly, the imaging optical system 100 according to the present embodiment may be mounted on a small terminal or a thin terminal as it is optically designed. The first reflector P1 and the second reflector P2 may have a prism shape. However, the shapes of the first and second reflectors P1 and P2 are not limited to prisms.

Next, the shapes of the first reflector P1 and the second reflector P2 will be described.

The first reflector P1 may be formed in a substantially polyhedral shape. For example, the first reflector P1 may be formed in a hexahedral shape. However, the shape of the first reflector P1 is not limited to a hexahedron. A cross-sectional shape of the first reflector P1 parallel to the optical axis C (or a cross-sectional shape of the first reflector P1 in which an optical path is formed) may be substantially rectangular. For example, the cross section of the first reflector P1 may have a trapezoid shape in which a pair of opposite sides are parallel.

As shown in FIG. 1 , the cross section of the first reflector P1 may have a quadrangular shape having four sides. For example, the cross section of the first reflector P1 may include a first side P1S1, a second side P1S2, a third side P1S3, and a fourth side P1S4. However, the cross section of the first reflector P1 is not necessarily rectangular.

The first reflector P1 is configured to refract light incident from the third lens 130 to the second reflector P2. To this end, the first reflector P1 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the first reflector P1 may include three reflective surfaces and two transmission surfaces.

The first reflector P1 may include a plurality of transmission surfaces. For example, the first side P1S1 and the third side P1S3 of the first reflector P1 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the first reflector P1, the first side P1S1 closest to the third lens 130 forms a first transmission surface, and in the cross-sectional shape of the first reflector P1, The third side P1S3 closest to the second reflector P2 may form a second transmission surface.

The first reflector P1 may include a plurality of reflective surfaces. For example, the second side P1S2, the third side P1S3, and the fourth side P1S4 of the first reflecting unit P1 are the first reflecting surface (or the first frontmost reflecting surface) and the second half, respectively. A slope (or first rearmost reflective surface) and a third reflective surface (or first reflective surface) may be formed. In other words, the second side P1S2 forms a first reflection surface that reflects light incident through the first side P1S1, and the third side P1S3 facing the second side P1S2 is A second reflective surface is formed to reflect the light reflected from the two sides P1S2 to the fourth side P1S4, and the fourth side P1S4 formed parallel to the first side P1S1 is the third side P1S3. ) may form a third reflection surface for re-reflecting light totally reflected from the third side P1S3.

That is, in the first reflector P1 according to the present embodiment, the first side P1S1 forms the first transmission surface, the second side P1S2 forms the first reflection surface, and the third side P1S3 ) may form a second transmission surface and a second reflective surface, and the fourth side P1S4 may form a third reflective surface.

The second reflector P2 may be formed in a substantially polyhedral shape. For example, the second reflector P2 may be formed in a pentahedral shape. However, the shape of the second reflector P2 is not limited to the pentahedron. A cross-sectional shape of the second reflector P2 parallel to the optical axis C may be substantially triangular.

As shown in FIG. 1 , the cross section of the second reflector P2 may have a triangular shape with three sides. For example, the cross section of the second reflector P2 may include a first side P2S1, a second side P2S2, and a third side P2S3. However, the cross section of the second reflector P2 is not necessarily triangular.

The second reflector P2 is configured to form an image of light emitted from the first reflector P1 on the upper surface IP. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include three reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the first reflector P1 forms the first transmission surface, and the cross-sectional shape of the second reflector P2 In , the third side P2S3 closest to the upper surface IP may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the first side (P2S2), the second side (P2S2), and the third side (P2S3) of the second reflecting unit (P2) form a first reflection surface, a second reflection surface, and a third reflection surface, respectively. can do. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1 to the first side P2S1, and the first side P2S1 is the third side. A second reflection surface that totally reflects the light reflected from (P2S3) to the second side (P2S2) is formed, and the second side (P2S2) transmits the light totally reflected from the third side (P2S3) toward the third side (P2S3). It is possible to form a third reflective surface for re-reflection.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface and the second reflection surface, and the second side P2S2 forms the third reflection surface. The third side P2S3 may form a second transmission surface and a first reflection surface.

The first reflector P1 and the second reflector P2 may be configured to establish a predetermined mechanical relationship. For example, the third side P1S3 of the first reflector P1 may be parallel to the first side P2S1 of the second reflector P2. As another example, the fourth side P1S4 of the first reflector P1 may be parallel to the third side P2S3 of the second reflector P2. As another example, an angle θ1 formed between the third side P1S3 and the fourth side P1S4 of the first reflector P1 is equal to the first side P2S1 and the third side P2S1 of the second reflector P2. It may have the same size as the angle θ2 formed by (P2S3).

The first reflector P1 and the second reflector P2 may be disposed at a predetermined interval. For example, the distance d from the third side P1S3 of the first reflector P1 to the first side P2S1 of the second reflector P2 may be determined to be non-zero.

Since the imaging optical system 100 configured as above can secure an optical path of considerable length (or distance) through the first reflector P1 and the second reflector P2, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 100 according to this embodiment includes the first lens 110, the second lens 120, the third lens 130, the first reflector P1, and the second reflector P2. Since it can be integrated in a limited space, it can be installed in a small or ultra-thin terminal.

The imaging optical system 100 configured as above may exhibit aberration characteristics of the form shown in FIG. 2 . Tables 1 and 2 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 5.055 2.552 1.585 59.5 9.5296 S2 44.211 0.100 S3 2nd lens 19.200 0.604 1.619 26.0 -7.3745 S4 3.645 1.781 S5 3rd lens 5.746 0.934 1.678 19.2 20.0009 S6 9.320 0.800 S7 1st reflector Infinity 1.800 1.519 64.2 S8 Infinity 6.000 1.519 64.2 S9 Infinity 2.000 1.519 64.2 S10 Infinity 1.000 1.519 64.2 S11 Infinity 2.000 S12 2nd reflector Infinity 1.000 1.519 64.2 S13 Infinity 2.000 1.519 64.2 S14 Infinity 5.000 1.519 64.2 S15 Infinity 1.600 1.519 64.2 S16 Infinity 1.124 1.519 64.2 S17 upper face Infinity -0.010

side number S1 S2 S3 S4 S5 S6 K 0 0 3.853E+01 2.185E-01 -6.926E-01 8.950E+00 A 0 0 1.402E-02 1.702E-02 5.213E-03 2.804E-03 B 0 0 1.316E-03 -1.545E-04 -3.164E-04 -4.304E-04 C 0 0 -1.310E-05 1.933E-04 1.675E-05 -1.909E-04 D 0 0 3.115E-04 1.730E-05 -3.925E-07 -1.245E-04 E 0 0 0 0 0 0 F 0 0 0 0 0 0 G 0 0 0 0 0 0 H 0 0 0 0 0 0 J 0 0 0 0 0 0

Next, a modified example of the imaging optical system 100 according to the first embodiment will be described with reference to FIGS. 3 to 7 . For reference, in the following description, a detailed description of the same or similar configuration as that shown in FIG. 1 will be omitted. In addition, in the following description, some components may be used with different reference numerals from the above-described embodiments.

The imaging optical system 100 according to the first embodiment may be modified into the form shown in FIGS. 3 to 7 .

First, an imaging optical system according to a first modified example will be described with reference to FIG. 3 .

In the imaging optical system 101 according to the first modified example, the first reflecting unit P1 and the second reflecting unit P2 may be formed of a plurality of reflecting members. More specifically, the first reflector P1 is composed of the first reflector M1, the second reflector M2, and the third reflector M3, and the second reflector P2 is the fourth reflector. It may be composed of a member M4, a fifth reflective member M5, and a sixth reflective member M6.

In the first reflection part (P1), the first reflection member (M1) reflects light incident from the second lens (120) to the second reflection member (M2), and the second reflection member (M2) is the first reflection member The light reflected through the (M1) is totally reflected by the third reflective member (M3), and the third reflective member (M3) reflects the light reflected through the second reflective member (M2) to the second reflective part (P2). can make it For reference, in the first reflector P1, the second reflector M2 may reflect the light of the first reflector M1 and transmit the light of the third reflector M3 at the same time. there is.

In the second reflector P2, the fourth reflector M4 transmits light incident from the first reflector P1 and transmits the light reflected from the fifth reflector M5 to the sixth reflector M6. ), the fifth reflecting member M5 reflects the light incident from the first reflecting member P1 to the fourth reflecting member M4, and the sixth reflecting member M6 reflects the light incident from the first reflecting member P1 to the fourth reflecting member M4. ) may be configured to reflect light reflected from the upper surface IP.

The imaging optical system 101 according to the first modified example may be composed of two lenses. For example, the imaging optical system 101 may include a first lens 110 and a second lens 120 sequentially disposed from the object side. In the first modified example, the first lens 110 may have a positive refractive power, and may have a shape in which an object side surface is convex and an image side surface is concave. In the first modified example, the second lens 120 may have positive or negative refractive power, and may have a shape in which an object side surface is convex and an image side surface is concave. However, the refractive power and shape of the first lens 110 and the second lens 120 are not limited to the above-described forms.

An imaging optical system according to a second modified example will be described with reference to FIG. 4 .

In the imaging optical system 102 according to the second modified example, each of the first and second reflectors P1 and P2 may be configured with a plurality of prisms. In other words, the first reflector P1 is composed of the first prism PR1 and the second prism PR2, and the second reflector P2 includes the third prism P3 and the fourth prism P4. may consist of

The first reflector P1 may be configured in a form in which the first prism PR1 and the second prism PR2 are coupled or bonded. In other words, one surface of the first prism PR1 and one surface of the second prism PR2 may be configured in parallel or may be in close contact with each other without an air gap.

In the first reflecting part P1, the first surface PR1S1 and the second surface PR1S2 of the first prism PR1 form a first transmission surface and a first reflection surface, respectively, and The second surface PR2S2 and the third surface PR2S3 may form a third reflective surface and a second reflective surface, respectively, and the third surface PR2S3 of the second prism PR2 may form a second transmission surface. there is. In addition, the third surface PR1S3 of the first prism PR1 is configured parallel to the first surface PR2S1 of the second prism PR2 or has a gap with the first surface PR2S1 of the second prism PR2. can be joined without

The second reflector P2 may be configured in a form in which the third prism PR3 and the fourth prism PR4 are coupled or bonded. In other words, one side of the third prism PR3 and one side of the fourth prism PR4 may be configured in parallel or may be in close contact with each other without an air gap.

In the second reflection part P2, the first surface PR3S1 of the third prism PR3 forms a first transmission surface and a second reflection surface, and the second surface PR3S2 of the third prism PR3 forms a first transmission surface and a second reflection surface. A first reflective surface is formed, the second surface PR4S2 of the fourth prism PR4 forms a third reflective surface, and the third surface PR4S3 of the fourth prism PR4 forms a second transmission surface. can In addition, the third surface PR3S3 of the third prism PR3 is configured parallel to the first surface PR4S1 of the fourth prism PR4 or has a gap with the first surface PR4S1 of the fourth prism PR4. can be joined without

The imaging optical system 102 according to the second modified example may be composed of a single lens. For example, the imaging optical system 102 may include a first lens 110 . In the second modified example, the first lens 110 may have a positive refractive power, and may have a convex object side surface and a concave image side surface. However, the refractive power and shape of the first lens 110 are not limited to those described above.

An imaging optical system according to a third modification to a fifth modification will be described with reference to FIGS. 5 to 7 . For reference, in the following description, a detailed description of the same or similar configuration as that shown in FIG. 1 will be omitted.

The imaging optical systems 103, 104, and 105 according to the third to fifth modifications may further include a filter IF. For example, the imaging optical system 103 according to the third modified example further includes a filter IF disposed between the third lens 130 and the first reflector P1 as shown in FIG. As shown in FIG. 6, the imaging optical system 104 according to the quadrilateral example includes a filter IF disposed between the first reflecting unit P1 and the second reflecting unit P2, and according to the fifth modification example As shown in FIG. 7 , the imaging optical system 105 according to the present invention may include a filter IF attached to or integrally formed on one surface of the first reflector P1 or the second reflector P2.

Next, an imaging optical system according to the second embodiment will be described with reference to FIG. 8 .

The imaging optical system 200 according to the present embodiment includes a lens group including a first lens 210, a second lens 220, and a third lens 230, a first reflector P1, and a second reflector ( P2) is included. However, the configuration of the imaging optical system 200 is not limited to the members described above. For example, the imaging optical system 200 may further include one or more lenses.

The first lens 210 to the third lens 230 may be sequentially disposed from the object side. For example, the second lens 220 may be disposed on the image side of the first lens 210, and the third lens 230 may be disposed on the image side of the second lens 220. The first lens 210 to the third lens 230 may be disposed at a predetermined interval. For example, the image side of the first lens 210 does not contact the object side of the second lens 220, and the image side of the second lens 220 does not contact the object side of the third lens 230. can be placed so as not to However, the first lens 210 to the third lens 230 are not necessarily arranged in a non-contact state. For example, the image side of the first lens 210 may contact the object side of the second lens 220 or the image side of the second lens 220 may contact the object side of the third lens 230. may be

Next, the characteristics of the first lens 210 to the third lens 230 will be described.

The first lens 210 has refractive power. For example, the first lens 210 may have positive refractive power. The first lens 210 may have a convex shape on one surface. For example, the first lens 210 may have a convex object side surface. One surface of the first lens 210 may be concave. For example, the first lens 210 may have a concave image side surface. However, the image side of the first lens 210 is not limited to a concave shape. For example, an image side surface of the first lens 210 may have a convex shape if necessary. The first lens 210 may include a spherical surface. For example, both the object side and the image side of the first lens 210 may be formed as spherical surfaces.

The second lens 220 has refractive power. For example, the second lens 220 may have negative refractive power. The second lens 220 may have a convex shape on one surface. For example, the second lens 220 may have a convex object side surface. However, the object side of the second lens 220 is not limited to a convex shape. For example, the object side of the second lens 220 may have a concave shape as needed. The second lens 220 may have a concave shape on one surface. For example, the second lens 220 may have a concave image side surface. The second lens 220 may include an aspherical surface. For example, at least one of the object side and the image side of the second lens 220 may be formed as an aspheric surface.

The third lens 230 has refractive power. For example, the third lens 230 may have positive or negative refractive power. The third lens 230 may have a convex shape on one surface. For example, the third lens 230 may have a shape in which an object side surface is convex. The third lens 230 may have a concave shape on one surface. For example, the third lens 230 may have a concave image side surface. However, the image side of the third lens 230 is not limited to a concave shape. For example, an image side surface of the third lens 230 may have a convex shape if necessary. The third lens 230 may include an aspheric surface. For example, at least one of the object side and the image side of the third lens 230 may be formed as an aspheric surface.

The first reflector P1 and the second reflector P2 may be disposed between the third lens 230 and the image surface IP. The first reflector P1 and the second reflector P2 may be configured to reduce the external distance from the image side surface of the third lens 230 to the image surface IP. In other words, the first reflector P1 and the second reflector P2 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 230 to the image surface, and the third lens 230 The external distance or size from the image side surface of the lens 230 to the image surface may be reduced. Accordingly, the imaging optical system 200 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The first reflector P1 and the second reflector P2 may have a prism shape. However, the shapes of the first and second reflectors P1 and P2 are not limited to prisms.

Next, the shapes of the first reflector P1 and the second reflector P2 will be described.

The first reflector P1 may be formed in a substantially polyhedral shape. For example, the first reflector P1 may be formed in a hexahedral shape. However, the shape of the first reflector P1 is not limited to a hexahedron. A cross-sectional shape of the first reflector P1 parallel to the optical axis C (or a cross-sectional shape of the first reflector P1 in which an optical path is formed) may be substantially rectangular. For example, the cross section of the first reflector P1 may have a trapezoid shape in which a pair of opposite sides are parallel.

As shown in FIG. 8 , the cross section of the first reflector P1 may have a quadrangular shape having four sides. For example, the cross section of the first reflector P1 may include a first side P1S1, a second side P1S2, a third side P1S3, and a fourth side P1S4. However, the cross section of the first reflector P1 is not necessarily rectangular.

The first reflector P1 is configured to refract light incident from the third lens 230 to the second reflector P2. To this end, the first reflector P1 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the first reflector P1 may include three reflective surfaces and two transmission surfaces.

The first reflector P1 may include a plurality of transmission surfaces. For example, the first side P1S1 and the third side P1S3 of the first reflector P1 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the first reflector P1, the first side P1S1 closest to the third lens 230 forms a first transmission surface, and in the cross-sectional shape of the first reflector P1, The third side P1S3 closest to the second reflector P2 may form a second transmission surface.

The first reflector P1 may include a plurality of reflective surfaces. For example, the second side (P1S2), the third side (P1S3), and the fourth side (P1S4) of the first reflection part (P1) form the first reflection surface, the second reflection surface, and the third reflection surface, respectively. can do. In other words, the second side P1S2 forms a first reflection surface that reflects light incident through the first side P1S1, and the third side P1S3 facing the second side P1S2 is A second reflective surface is formed to reflect the light reflected from the two sides P1S2 to the fourth side P1S4, and the fourth side P1S4 formed parallel to the first side P1S1 is the third side P1S3. ) may form a third reflection surface for re-reflecting light totally reflected from the third side P1S3.

That is, in the first reflector P1 according to the present embodiment, the first side P1S1 forms the first transmission surface, the second side P1S2 forms the first reflection surface, and the third side P1S3 ) may form a second transmission surface and a second reflective surface, and the fourth side P1S4 may form a third reflective surface.

The second reflector P2 may be formed in a substantially polyhedral shape. For example, the second reflector P2 may be formed in a hexahedral shape. However, the shape of the second reflector P2 is not limited to a hexahedron. A cross-sectional shape of the second reflector P2 parallel to the optical axis C may be substantially rectangular.

As shown in FIG. 8 , the cross section of the second reflector P2 may have a quadrangular shape having four sides. For example, the cross section of the second reflector P2 may include a first side P2S1, a second side P2S2, a third side P2S3, and a fourth side P2S4. However, the cross section of the second reflector P2 is not necessarily rectangular.

The second reflector P2 is configured to form or reflect the light emitted from the first reflector P1 onto the upper surface IP. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include three reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the fourth side P2S4 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the first reflector P1 forms the first transmission surface, and the cross-sectional shape of the second reflector P2 In , the fourth side P2S4 closest to the upper surface IP may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the first side (P2S2), the second side (P2S2), and the third side (P2S3) of the second reflecting unit (P2) form a first reflection surface, a second reflection surface, and a third reflection surface, respectively. can do. In other words, the second side P2S2 forms a first reflection surface that reflects light incident through the first side P2S1 to the first side P2S1, and the first side P2S1 forms a second side. A second reflection surface that totally reflects the light reflected from P2S2 to the third side P2S3 is formed, and the third side P2S3 transmits light totally reflected from the first side P2S1 to the fourth side P2S4 or P2S3. A third reflective surface for reflecting to the upper surface IP may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface and the second reflection surface, and the second side P2S2 forms the first reflection surface. The third side P2S3 may form a third reflective surface, and the fourth side P2S4 may form a second transmission surface.

The first reflector P1 and the second reflector P2 may be configured to establish a predetermined mechanical relationship. For example, the third side P1S3 of the first reflector P1 may be parallel to the first side P2S1 of the second reflector P2. As another example, the fourth side P1S4 of the first reflector P1 may be parallel to the second side P2S2 of the second reflector P2. As another example, an angle θ1 formed by the third side P1S3 and the fourth side P1S4 of the first reflector P1 is equal to the first side P2S1 and the second side P2S1 of the second reflector P2. It may have the same size as the angle θ2 formed by (P2S2).

The first reflector P1 and the second reflector P2 may be disposed at a predetermined interval. However, the first reflector P1 and the second reflector P2 are not necessarily disposed at intervals. For example, it may be possible to place one surface of the first reflector P1 and one surface of the second reflector P2 in contact with each other.

Since the imaging optical system 200 configured as above can secure an optical path of considerable length (or distance) through the first reflector P1 and the second reflector P2, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 200 according to the present embodiment includes the first lens 210, the second lens 220, the third lens 230, the first reflector P1, and the second reflector P2. Since it can be integrated in a limited space, it can be installed in a small or ultra-thin terminal.

The imaging optical system 200 configured as above may exhibit aberration characteristics of the form shown in FIG. 9 . Tables 3 and 4 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 5.056 2.550 1.585 59.5 9.6058 S2 41.104 0.096 S3 2nd lens 18.236 0.620 1.619 26.0 -7.0948 S4 3.494 1.408 S5 3rd lens 5.666 0.799 1.667 20.3 18.6031 S6 9.842 2.000 S7 1st reflector Infinity 2.000 1.518 64.2 S8 Infinity 6.000 1.518 64.2 S9 Infinity 2.000 1.518 64.2 S10 Infinity 1.000 1.518 64.2 S11 Infinity 2.000 S12 2nd reflector Infinity 1.000 1.518 64.2 S13 Infinity 2.000 1.518 64.2 S14 Infinity 5.000 1.518 64.2 S15 Infinity 1.500 1.518 64.2 S16 Infinity 0.500 S17 Infinity 0.210 1.518 64.2 S18 Infinity 0.448 S19 upper face Infinity -0.010

side number S1 S2 S3 S4 S5 S6 K 0 0 3.899E+01 2.304E-01 -5.662E-01 9.108E+00 A 0 0 1.325E-02 1.731E-02 5.315E-03 2.446E-03 B 0 0 1.404E-03 -4.154E-04 -3.214E-04 -3.917E-04 C 0 0 1.519E-04 3.083E-04 1.504E-05 -1.280E-04 D 0 0 4.678E-04 6.369E-05 -5.662E-09 -1.154E-04 E 0 0 0 0 0 0 F 0 0 0 0 0 0 G 0 0 0 0 0 0 H 0 0 0 0 0 0 J 0 0 0 0 0 0

The imaging optical system 200 according to the second embodiment may be modified into the form shown in FIG. 10 . A modified example of the imaging optical system will be described with reference to FIG. 10 .

In the imaging optical system 201 according to the modified example, the first reflecting unit P1 and the second reflecting unit P2 may be configured with a plurality of reflecting members. More specifically, the first reflector P1 is composed of the first reflector M1, the second reflector M2, and the third reflector M3, and the second reflector P2 is the fourth reflector. It may be composed of a member M4, a fifth reflective member M5, and a sixth reflective member M6.

In the first reflection part (P1), the first reflection member (M1) reflects light incident from the second lens (120) to the second reflection member (M2), and the second reflection member (M2) is the first reflection member The light reflected through the (M1) is totally reflected by the third reflective member (M3), and the third reflective member (M3) reflects the light reflected through the second reflective member (M2) to the second reflective part (P2). can make it For reference, in the first reflector P1, the second reflector M2 may reflect the light of the first reflector M1 and transmit the light of the third reflector M3 at the same time. there is.

In the second reflector P2, the fourth reflector M4 transmits light incident from the first reflector P1 and transmits the light reflected from the fifth reflector M5 to the sixth reflector M6. ), the fifth reflecting member M5 reflects the light incident from the first reflecting member P1 to the fourth reflecting member M4, and the sixth reflecting member M6 reflects the light incident from the first reflecting member P1 to the fourth reflecting member M4. ) may be configured to reflect light reflected from the upper surface IP.

Next, an imaging optical system according to a third embodiment will be described with reference to FIG. 11 .

The imaging optical system 300 according to this embodiment includes a lens group LG, a first reflector P1, and a second reflector P2. However, the configuration of the imaging optical system 300 is not limited to the members described above.

The lens group LG may include a plurality of lenses. For example, the lens group LG may include a first lens 310 , a second lens 320 , and a third lens 330 . However, the configuration of the lens group LG is not limited to the first lens 310 to the third lens 330 . The first lens 310 to the third lens 330 may be sequentially disposed from the object side. For example, the second lens 320 may be disposed on the image side of the first lens 310, and the third lens 330 may be disposed on the image side of the second lens 320. The first lens 310 to the third lens 330 may be disposed at a predetermined interval. For example, the image side of the first lens 310 does not contact the object side of the second lens 320, and the image side of the second lens 320 does not contact the object side of the third lens 330. can be placed so as not to However, the first lens 310 to the third lens 330 are not necessarily arranged in a non-contact state. For example, the image side of the first lens 310 may contact the object side of the second lens 320 or the image side of the second lens 320 may contact the object side of the third lens 330. may be

Next, the characteristics of the first lens 310 to the third lens 330 will be described.

The first lens 310 has refractive power. For example, the first lens 310 may have positive refractive power. The first lens 310 may have a convex shape on one surface. For example, the first lens 310 may have a convex object side surface. One surface of the first lens 310 may be concave. For example, the first lens 310 may have a concave image side surface. However, the image side of the first lens 310 is not limited to a concave shape. For example, an image side surface of the first lens 310 may have a convex shape if necessary. The first lens 310 may include a spherical surface. For example, both the object side and the image side of the first lens 310 may be formed as spherical surfaces.

The second lens 320 has refractive power. For example, the second lens 320 may have negative refractive power. The second lens 320 may have a convex shape on one surface. For example, the second lens 320 may have a shape in which an object side surface is convex. However, the object side of the second lens 320 is not limited to a convex shape. For example, the object side of the second lens 320 may have a concave shape as needed. The second lens 320 may have a concave shape on one surface. For example, the second lens 320 may have a concave image side surface. The second lens 320 may include an aspheric surface. For example, at least one of the object side and the image side of the second lens 320 may be formed as an aspheric surface.

The third lens 330 has refractive power. For example, the third lens 330 may have positive or negative refractive power. The third lens 330 may have a convex shape on one surface. For example, the third lens 330 may have a shape in which an object side surface is convex. The third lens 330 may have a concave shape on one surface. For example, the third lens 330 may have a concave image side surface. However, the image side of the third lens 330 is not limited to a concave shape. For example, an image side surface of the third lens 330 may have a convex shape if necessary. The third lens 330 may include an aspheric surface. For example, at least one of the object side and the image side of the third lens 330 may be formed as an aspherical surface.

The first reflector P1 and the second reflector P2 may be disposed between the third lens 330 and the image surface IP. The first reflector P1 and the second reflector P2 may be configured to reduce the external distance from the image side surface of the third lens 330 to the image surface IP. In other words, the first reflector P1 and the second reflector P2 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 330 to the image surface, and the third lens 330 The external distance or size from the image side surface of the lens 330 to the image surface may be reduced. Accordingly, the imaging optical system 300 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The first reflector P1 and the second reflector P2 may have a prism shape. However, the shapes of the first and second reflectors P1 and P2 are not limited to prisms.

Next, the shapes of the first reflector P1 and the second reflector P2 will be described.

The first reflector P1 may be formed in a substantially polyhedral shape. For example, the first reflector P1 may be formed in a hexahedral shape. However, the shape of the first reflector P1 is not limited to a hexahedron. A cross-sectional shape of the first reflector P1 parallel to the optical axis C (or a cross-sectional shape of the first reflector P1 in which an optical path is formed) may be substantially rectangular. For example, the cross section of the first reflector P1 may have a trapezoid shape in which a pair of opposite sides are parallel.

As shown in FIG. 11, the cross section of the first reflector P1 may have a quadrangular shape having four sides. For example, the cross section of the first reflector P1 may include a first side P1S1, a second side P1S2, a third side P1S3, and a fourth side P1S4. However, the cross section of the first reflector P1 is not necessarily rectangular.

The first reflector P1 is configured to refract light incident from the third lens 330 to the second reflector P2. To this end, the first reflector P1 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the first reflector P1 may include three reflective surfaces and two transmission surfaces.

The first reflector P1 may include a plurality of transmission surfaces. For example, the first side P1S1 and the third side P1S3 of the first reflector P1 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the first reflector P1, the first side P1S1 closest to the third lens 330 forms a first transmission surface, and in the cross-sectional shape of the first reflector P1, The third side P1S3 closest to the second reflector P2 may form a second transmission surface.

The first reflector P1 may include a plurality of reflective surfaces. For example, the second side (P1S2), the third side (P1S3), and the fourth side (P1S4) of the first reflection part (P1) form the first reflection surface, the second reflection surface, and the third reflection surface, respectively. can do. In other words, the second side P1S2 forms a first reflection surface that reflects light incident through the first side P1S1, and the third side P1S3 facing the second side P1S2 is A second reflective surface is formed to reflect the light reflected from the two sides P1S2 to the fourth side P1S4, and the fourth side P1S4 formed parallel to the first side P1S1 is the third side P1S3. ) may form a third reflection surface for re-reflecting the light totally reflected from the third side (P1S3).

That is, in the first reflector P1 according to the present embodiment, the first side P1S1 forms the first transmission surface, the second side P1S2 forms the first reflection surface, and the third side P1S3 ) may form a second transmission surface and a second reflective surface, and the fourth side P1S4 may form a third reflective surface.

The second reflector P2 may be formed in a substantially polyhedral shape. For example, the second reflector P2 may be formed in a hexahedral shape. However, the shape of the second reflector P2 is not limited to a hexahedron. A cross-sectional shape of the second reflector P2 parallel to the optical axis C may be substantially rectangular.

As shown in FIG. 11, the cross section of the second reflector P2 may have a quadrangular shape having four sides. For example, the cross section of the second reflector P2 may include a first side P2S1, a second side P2S2, a third side P2S3, and a fourth side P2S4. Here, the third side P2S3 may be omitted if necessary (in this case, the cross section of the second reflector P2 may be configured as a triangle).

The second reflector P2 is configured to form or reflect the light emitted from the first reflector P1 onto the upper surface IP. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the fourth side P2S4 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the first reflector P1 forms the first transmission surface, and the cross-sectional shape of the second reflector P2 In , the fourth side P2S4 closest to the upper surface IP may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the first and second sides P2S2 and P2S2 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the second side P2S2 forms a first reflection surface that reflects light incident through the first side P2S1 to the first side P2S1, and the first side P2S1 forms a second side. A second reflection surface that totally reflects the light reflected from P2S2 to the fourth side P2S4 or the upper surface IP may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface and the second reflection surface, and the second side P2S2 forms the first reflection surface. The fourth side P2S4 may form a second transmission surface.

The first reflector P1 and the second reflector P2 may be configured to establish a predetermined mechanical relationship. For example, the third side P1S3 of the first reflector P1 may be parallel to the first side P2S1 of the second reflector P2. As another example, the fourth side P1S4 of the first reflector P1 may be parallel to the second side P2S2 of the second reflector P2. As another example, the angle θ1 between the third side P1S3 and the fourth side P1S4 of the first reflector P1 is the first side P2S1 and the second side P2S1 of the second reflector P2. It may be substantially the same size as the angle between (θ2) between (P2S2).

The first reflector P1 and the second reflector P2 may be disposed at a predetermined interval. However, the first reflector P1 and the second reflector P2 are not necessarily disposed at intervals. For example, it may be possible to place one surface of the first reflector P1 and one surface of the second reflector P2 in contact with each other.

Since the imaging optical system 300 configured as above can secure an optical path of considerable length (or distance) through the first reflector P1 and the second reflector P2, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 300 according to the present embodiment includes the first lens 310, the second lens 320, the third lens 330, the first reflector P1, and the second reflector P2. Since it can be integrated in a limited space, it can be installed in a small or ultra-thin terminal.

The imaging optical system 300 configured as above may exhibit aberration characteristics of the form shown in FIG. 12 . Tables 5 and 6 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 5.027 2.550 1.546 56.1 10.2279 S2 41.350 0.096 S3 2nd lens 18.336 0.620 1.640 24.0 -7.0808 S4 3.584 1.408 S5 3rd lens 5.510 0.799 1.678 19.2 15.9217 S6 10.604 1.000 S7 1st reflector Infinity 2.000 1.518 64.2 S8 Infinity 6.000 1.518 64.2 S9 Infinity 2.000 1.518 64.2 S10 Infinity 1.000 1.518 64.2 S11 Infinity 1.000 S12 2nd reflector Infinity 1.000 1.518 64.2 S13 Infinity 2.000 1.518 64.2 S14 Infinity 4.000 1.518 64.2 S15 Infinity 0.000 1.518 64.2 S16 Infinity 0.000 S17 Infinity 0.000 S18 Infinity 5.383 S19 upper face Infinity 0.000

side number S1 S2 S3 S4 S5 S6 K 0 0 3.802E+01 2.334E-01 -7.633E-01 9.249E+00 A 0 0 1.295E-02 1.658E-02 4.784E-03 8.126E-04 B 0 0 1.454E-03 2.157E-04 -2.739E-04 -4.059E-04 C 0 0 -2.283E-05 1.486E-04 5.443E-06 3.395E-05 D 0 0 2.983E-04 -3.554E-06 1.006E-05 -4.334E-05 E 0 0 0 0 0 0 F 0 0 0 0 0 0 G 0 0 0 0 0 0 H 0 0 0 0 0 0 J 0 0 0 0 0 0

The imaging optical system 300 according to the third embodiment may be deformable in the form shown in FIGS. 13 and 14 .

First, a first modified example of the imaging optical system will be described with reference to FIG. 13 .

In the imaging optical system 301 according to the first modified example, the first reflecting unit P1 and the second reflecting unit P2 may be formed of a plurality of reflecting members. More specifically, the first reflector P1 is composed of the first reflector M1, the second reflector M2, and the third reflector M3, and the second reflector P2 is the fourth reflector. It may be composed of a member M4 and a fifth reflective member M5.

In the first reflection part (P1), the first reflection member (M1) reflects light incident from the second lens (120) to the second reflection member (M2), and the second reflection member (M2) is the first reflection member The light reflected through the (M1) is totally reflected by the third reflective member (M3), and the third reflective member (M3) reflects the light reflected through the second reflective member (M2) to the second reflective part (P2). can make it For reference, in the first reflector P1, the second reflector M2 may reflect the light of the first reflector M1 and transmit the light of the third reflector M3 at the same time. there is.

In the second reflector P2, the fourth reflector M4 transmits the light incident from the first reflector P1 and also totally reflects the light reflected from the fifth reflector M5 to the upper surface IP. and the fifth reflective member M5 may be configured to reflect the light incident from the first reflective member P1 to the fourth reflective member M4.

An imaging optical system according to a second modified example will be described with reference to FIG. 14 .

In the imaging optical system 302 according to the second modified example, the first reflector P1 may be formed of a plurality of prisms. More specifically, the first reflector P1 may include a first prism PR1 and a second prism PR2, and the second reflector P2 may include a third prism P3.

The first reflector P1 may be configured in a form in which the first prism PR1 and the second prism PR2 are coupled or bonded. In other words, one surface of the first prism PR1 and one surface of the second prism PR2 may be configured in parallel or may be in close contact with each other without an air gap.

In the first reflecting part P1, the first surface PR1S1 and the second surface PR1S2 of the first prism PR1 form a first transmission surface and a first reflection surface, respectively, and The second surface PR2S2 and the third surface PR2S3 may form a third reflective surface and a second reflective surface, respectively, and the third surface PR2S3 of the second prism PR2 may form a second transmission surface. there is. In addition, the third surface PR1S3 of the first prism PR1 is configured parallel to the first surface PR2S1 of the second prism PR2 or has a gap with the first surface PR2S1 of the second prism PR2. can be joined without

The second reflector P2 may include one third prism PR3. In the second reflection part P2, the first surface PR3S1 of the third prism PR3 forms a first transmission surface and a second reflection surface, and the second surface PR3S2 forms a first reflection surface. The third surface PR3S3 may form a second transmission surface.

Next, an imaging optical system according to a fourth embodiment will be described with reference to FIG. 15 .

The imaging optical system 400 according to this embodiment includes a first lens group LG1, a first reflector P1, a second lens group LG2, a second reflector P2, It includes a third reflector (P2). However, the configuration of the imaging optical system 400 is not limited to the members described above.

The first lens group LG1 may include a plurality of lenses. For example, the first lens group LG1 may include a first lens 410 and a second lens 420 . However, the configuration of the first lens group LG1 is not limited to the first lens 410 and the second lens 420 . The first lens 410 and the second lens 420 may be sequentially disposed from the object side. The first lens 410 and the second lens 420 may be disposed at a predetermined interval. For example, the image side of the first lens 410 may be disposed so as not to face the object side of the second lens 420 .

Next, characteristics of the first lens 410 and the second lens 420 will be described.

The first lens 410 has refractive power. For example, the first lens 410 may have positive refractive power. The first lens 410 has a shape in which an object side surface is convex and an image side surface is convex. The first lens 410 may include a spherical surface. For example, both the object side and the image side of the first lens 410 may be formed as spherical surfaces.

The second lens 420 has refractive power. For example, the second lens 420 may have negative refractive power. The second lens 420 has a convex object side and a concave image side. The second lens 420 may include an aspherical surface. For example, both the object side and the image side of the second lens 420 may be formed as aspheric surfaces.

The first reflector P1 may be configured to totally reflect light incident through the first lens group LG1 to the second lens group LG2. For example, the first reflector P1 may be configured to reflect light incident through the first lens group LG1 in a direction of approximately 90 degrees.

The second lens group LG2 may include one or more lenses. For example, the second lens group LG2 may include the third lens 430 . The third lens 430 has refractive power. For example, the third lens 430 may have negative refractive power. The third lens 430 has a convex object side surface and a concave image side surface. The third lens 430 may include an aspherical surface. For example, an image side surface of the third lens 430 may be formed as an aspherical surface.

The second reflector P2 and the third reflector P3 may be disposed between the third lens 430 and the image surface IP. The second reflector P2 and the third reflector P3 may be configured to reduce the external distance from the image side surface of the third lens 430 to the image surface IP. In other words, the second reflector P2 and the third reflector P3 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 430 to the image surface, and the third reflector P3 The external distance or size from the image side surface of the lens 430 to the image surface may be reduced. Accordingly, the imaging optical system 400 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The second reflector P2 and the third reflector P3 may have a prism shape. However, the shapes of the second and third reflectors P2 and P3 are not limited to prisms.

Next, the shapes of the second reflector P2 and the third reflector P3 will be described.

A cross section of the second reflector P2 may be formed as a triangle having three sides. For example, the cross-sectional shape of the second reflector P2 may be a triangle including a first side P2S1, a second side P2S2, and a third side P2S3.

The second reflector P2 is configured to refract light incident from the third lens 430 to the third reflector P3. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the third lens 430 forms a first transmission surface, and in the cross-sectional shape of the second reflector P2, The third side P2S3 closest to the third reflector P3 may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the second and third sides P2S2 and P2S3 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1, and the second side P2S3 reflects the light reflected from the third side P2S3. A second reflection surface for re-reflecting to the third side P2S3 may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface, the second side P2S2 forms the second reflection surface, and the third side P2S3 ) may form the second transmission surface and the first reflection surface.

A cross section of the third reflector P3 may be formed as a triangle with three sides. For example, the cross-sectional shape of the third reflector P3 may be formed as a triangle including the first side P3S1, the third side P3S2, and the third side P3S3.

The third reflector P3 is configured to form or reflect the light emitted from the second reflector P2 to the upper surface IP. To this end, the third reflector P3 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the third reflector P3 may include two reflective surfaces and two transmission surfaces.

The third reflector P3 may include a plurality of transmission surfaces. For example, the first side P3S1 and the second side P3S2 of the third reflector P3 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the third reflector P3, the first side P3S1 closest to the second reflector P2 forms the first transmission surface, and the cross-sectional shape of the third reflector P3 In , the second side P3S2 closest to the upper surface IP may form a second transmission surface.

The third reflector P3 may include a plurality of reflective surfaces. For example, the first side P3S1, the second side P3S2, and the third side P3S3 of the third reflector P3 may each form a reflective surface. In other words, the second side P3S2 forms a first reflection surface that reflects light incident through the first side P3S1 to the first side P3S1, and the first side P3S1 forms a second side. A second reflection surface that totally reflects light reflected from P3S2 to the third side P3S3 may be formed, and the third side P3S3 may form a third reflection surface that reflects incident light to the upper surface.

That is, in the third reflector P3 according to the present embodiment, the first side P3S1 forms the first transmission surface and the second reflection surface, and the second side P3S2 forms the first reflection surface and the second transmission surface. A surface is formed, and the third side P3S3 may form a third reflective surface.

The second reflector P2 and the third reflector P3 may be configured to establish a predetermined mechanical relationship. For example, the third side P2S3 of the second reflector P2 may be formed substantially parallel to the first side P3S1 of the third reflector P3. As another example, the second side P2S2 of the second reflector P2 may be formed substantially parallel to the second side P3S2 of the third reflector P3. As another example, the angle θ1 between the second side P2S2 and the third side P2S3 of the second reflector P2 is the first side P3S1 and the second side P3S1 of the third reflector P3. It may be substantially the same size as the angle between (θ2) between (P3S2).

The second reflector P2 and the third reflector P3 may be disposed at a predetermined interval. However, the second reflector P2 and the third reflector P3 are not necessarily spaced apart from each other. For example, it may be possible to place one surface of the second reflector P2 and one surface of the third reflector P3 in contact with each other.

Since the imaging optical system 400 configured as above can secure an optical path of considerable length (or distance) through the second reflector P2 and the third reflector P3, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 400 according to this embodiment includes a first lens 410, a second lens 420, a first reflector P1, a third lens 430, a second reflector P2, Since the third reflector P3 can be integrated in a limited space, it can be mounted on a small or ultra-thin terminal.

The imaging optical system 400 configured as above may exhibit aberration characteristics of the form shown in FIG. 16 . Tables 7 and 8 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 11.056 2.000 1.537 55.7 17.0716 S2 -50.158 0.100 S3 2nd lens 27.480 0.800 1.677 19.2 -48.8552 S4 14.833 1.000 S5 Infinity 0.000 S6 1st reflector Infinity 3.000 1.518 64.2 S7 Infinity 3.000 1.518 64.2 S8 Infinity 1.400 S9 3rd lens -36.453 0.800 1.537 55.7 -113.2090 S10 -22.610 0.400 S11 2nd reflector Infinity 4.000 1.518 64.2 S12 Infinity 4.000 1.518 64.2 S13 Infinity 2.000 1.518 64.2 S14 Infinity 0.500 S15 3rd reflector Infinity 1.600 1.518 64.2 S16 Infinity 3.000 1.518 64.2 S17 Infinity 6.000 1.518 64.2 S18 Infinity 2.600 1.518 64.2 S19 Infinity 0.200 S20 filter Infinity 0.210 1.518 64.2 S21 Infinity 0.475 S22 upper face Infinity -0.02

side number S1 S2 S3 S4 S9 S10 K 0 0 3.176E+01 1.320E+00 0 1.729E+01 A 0 0 2.834E-02 9.351E-03 0 1.834E-03 B 0 0 -2.453E-03 3.441E-03 0 -6.069E-04 C 0 0 1.570E-03 8.699E-04 0 3.451E-04 D 0 0 1.608E-03 1.564E-03 0 -1.466E-04 E 0 0 -2.680E-04 2.375E-04 0 1.272E-04 F 0 0 -1.804E-04 -4.904E-05 0 -9.930E-05 G 0 0 -1.569E-05 -2.252E-06 0 1.081E-05 H 0 0 0 0 0 0 J 0 0 0 0 0 0

Next, an imaging optical system according to a fifth embodiment will be described with reference to FIG. 17 .

The imaging optical system 500 according to this embodiment includes a first lens group LG1, a first reflector P1, a second lens group LG2, a second reflector P2, It includes a third reflector (P2). However, the configuration of the imaging optical system 500 is not limited to the members described above.

The first lens group LG1 may include a plurality of lenses. For example, the first lens group LG1 may include a first lens 510 and a second lens 520 . However, the configuration of the first lens group LG1 is not limited to the first lens 510 and the second lens 520 . The first lens 510 and the second lens 520 may be sequentially disposed from the object side. The first lens 510 and the second lens 520 may be disposed at a predetermined interval. For example, an image side surface of the first lens 510 may be disposed so as not to face an object side surface of the second lens 520 .

Next, characteristics of the first lens 510 and the second lens 520 will be described.

The first lens 510 has refractive power. For example, the first lens 510 may have positive refractive power. The first lens 510 has a shape in which an object side surface is convex and an image side surface is convex. The first lens 510 may include a spherical surface. For example, both the object side and the image side of the first lens 510 may be formed as spherical surfaces.

The second lens 520 has refractive power. For example, the second lens 520 may have negative refractive power. The second lens 520 has a convex object side and a concave image side. The second lens 520 may include an aspheric surface. For example, both the object side surface and the image side surface of the second lens 520 may be formed as aspheric surfaces.

The first reflector P1 may be configured to totally reflect light incident through the first lens group LG1 to the second lens group LG2. For example, the first reflector P1 may be configured to reflect light incident through the first lens group LG1 in a direction of approximately 90 degrees.

The second lens group LG2 may include one or more lenses. For example, the second lens group LG2 may include the third lens 530 . The third lens 530 has refractive power. For example, the third lens 530 may have negative refractive power. The third lens 530 has a convex object side surface and a concave image side surface. The third lens 530 may include an aspheric surface. For example, an image side surface of the third lens 530 may be formed as an aspherical surface.

The second reflector P2 and the third reflector P3 may be disposed between the third lens 530 and the image surface IP. The second reflector P2 and the third reflector P3 may be configured to reduce the external distance from the image side surface of the third lens 530 to the image surface IP. In other words, the second reflector P2 and the third reflector P3 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 530 to the image surface, and the third reflector P3 The external distance or size from the image side surface of the lens 530 to the image surface may be reduced. Accordingly, the imaging optical system 500 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The second reflector P2 and the third reflector P3 may have a prism shape. However, the shapes of the second and third reflectors P2 and P3 are not limited to prisms.

Next, the shapes of the second reflector P2 and the third reflector P3 will be described.

A cross section of the second reflector P2 may be formed as a triangle having three sides. For example, the cross-sectional shape of the second reflector P2 may be a triangle including a first side P2S1, a second side P2S2, and a third side P2S3.

The second reflector P2 is configured to refract light incident from the third lens 530 to the third reflector P3. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the third lens 530 forms the first transmission surface, and in the cross-sectional shape of the second reflector P2, The third side P2S3 closest to the third reflector P3 may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the second and third sides P2S2 and P2S3 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1, and the second side P2S3 reflects the light reflected from the third side P2S3. A second reflection surface for re-reflecting to the third side P2S3 may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface, the second side P2S2 forms the second reflection surface, and the third side P2S3 ) may form the second transmission surface and the first reflection surface.

A cross section of the third reflector P3 may be formed as a triangle with three sides. For example, the cross-sectional shape of the third reflector P3 may be formed as a triangle including the first side P3S1, the third side P3S2, and the third side P3S3.

The third reflector P3 is configured to form or reflect the light emitted from the second reflector P2 to the upper surface IP. To this end, the third reflector P3 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the third reflector P3 may include two reflective surfaces and two transmission surfaces.

The third reflector P3 may include a plurality of transmission surfaces. For example, the first side P3S1 and the second side P3S2 of the third reflector P3 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the third reflector P3, the first side P3S1 closest to the second reflector P2 forms the first transmission surface, and the cross-sectional shape of the third reflector P3 In , the second side P3S2 closest to the upper surface IP may form a second transmission surface.

The third reflector P3 may include a plurality of reflective surfaces. For example, the first side P3S1, the second side P3S2, and the third side P3S3 of the third reflector P3 may each form a reflective surface. In other words, the second side P3S2 forms a first reflection surface that reflects light incident through the first side P3S1 to the first side P3S1, and the first side P3S1 forms a second side. A second reflection surface that totally reflects the light reflected from P3S2 to the third side P3S3 may be formed, and the third side P3S3 may form a third reflection surface that reflects incident light to the upper surface.

That is, in the third reflector P3 according to the present embodiment, the first side P3S1 forms the first transmission surface and the second reflection surface, and the second side P3S2 forms the first reflection surface and the second transmission surface. A surface is formed, and the third side P3S3 may form a third reflective surface.

The second reflector P2 and the third reflector P3 may be configured to establish a predetermined mechanical relationship. For example, the third side P2S3 of the second reflector P2 may be formed substantially parallel to the first side P3S1 of the third reflector P3. As another example, the second side P2S2 of the second reflector P2 may be formed substantially parallel to the second side P3S2 of the third reflector P3. As another example, the angle θ1 between the second side P2S2 and the third side P2S3 of the second reflector P2 is the first side P3S1 and the second side P3S1 of the third reflector P3. It may be substantially the same size as the angle between (θ2) between (P3S2).

The second reflector P2 and the third reflector P3 may be disposed at a predetermined interval. However, the second reflector P2 and the third reflector P3 are not necessarily spaced apart from each other. For example, it may be possible to place one surface of the second reflector P2 and one surface of the third reflector P3 in contact with each other.

Since the imaging optical system 500 configured as above can secure an optical path of considerable length (or distance) through the second reflector P2 and the third reflector P3, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 500 according to this embodiment includes a first lens 510, a second lens 520, a first reflector P1, a third lens 530, a second reflector P2, Since the third reflector P3 can be integrated in a limited space, it can be mounted on a small or ultra-thin terminal.

The imaging optical system 500 configured as above may exhibit aberration characteristics of the form shown in FIG. 18 . Tables 9 and 10 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 6.603 1.200 1.537 55.7 10.2873 S2 -31.588 0.060 S3 2nd lens 16.634 0.480 1.677 19.2 -31.6702 S4 9.257 0.600 S5 Infinity 0.000 S6 1st reflector Infinity 1.800 1.518 64.2 S7 Infinity 1.800 1.518 64.2 S8 Infinity 0.840 S9 3rd lens -17.2853915 0.480 1.537 55.7 -33.0163 S10 -8.666 0.400 S11 2nd reflector Infinity 2.500 1.518 64.2 S12 Infinity 2.300 1.518 64.2 S13 Infinity 2.300 1.518 64.2 S14 Infinity 0.000 S15 3rd reflector Infinity 1.200 1.518 64.2 S16 Infinity 2.400 1.518 64.2 S17 Infinity 3.600 1.518 64.2 S18 Infinity 2.040 1.518 64.2 S19 Infinity 0.281 S20 upper face Infinity 0.000

side number S1 S2 S3 S4 S9 S10 K 0 0 2.946E+01 1.506E+00 0 7.453E+00 A 0 0 1.963E-02 5.278E-03 0 -1.637E-03 B 0 0 -2.596E-03 2.418E-03 0 5.417E-04 C 0 0 6.479E-04 -2.232E-04 0 -2.707E-04 D 0 0 1.047E-03 8.320E-04 0 4.196E-05 E 0 0 -2.255E-04 3.574E-04 0 7.355E-05 F 0 0 -2.017E-04 -3.492E-04 0 -1.660E-04 G 0 0 -2.380E-06 1.385E-04 0 -1.010E-04 H 0 0 0 0 0 0 J 0 0 0 0 0 0

Next, an imaging optical system according to a sixth embodiment will be described with reference to FIG. 19 .

The imaging optical system 600 according to this embodiment includes a first lens group LG1, a first reflector P1, a second lens group LG2, a second reflector P2, It includes a third reflector (P2). However, the configuration of the imaging optical system 600 is not limited to the members described above.

The first lens group LG1 may include a plurality of lenses. For example, the first lens group LG1 may include a first lens 610 and a second lens 620 . However, the configuration of the first lens group LG1 is not limited to the first lens 610 and the second lens 620 . The first lens 610 and the second lens 620 may be sequentially disposed from the object side. The first lens 610 and the second lens 620 may be disposed at a predetermined interval. For example, an image side surface of the first lens 610 may be disposed not to face an object side surface of the second lens 620 .

Next, characteristics of the first lens 610 and the second lens 620 will be described.

The first lens 610 has refractive power. For example, the first lens 610 may have positive refractive power. The first lens 610 has a shape in which an object side surface is convex and an image side surface is convex. The first lens 610 may include a spherical surface. For example, both the object side and the image side of the first lens 610 may be formed as spherical surfaces.

The second lens 620 has refractive power. For example, the second lens 620 may have negative refractive power. The second lens 620 has a convex object side surface and a concave image side surface. The second lens 620 may include an aspheric surface. For example, both the object side and the image side of the second lens 620 may be formed as aspheric surfaces.

The first reflector P1 may be configured to totally reflect light incident through the first lens group LG1 to the second lens group LG2. For example, the first reflector P1 may be configured to reflect light incident through the first lens group LG1 in a direction of approximately 90 degrees.

The second lens group LG2 may include two lenses. For example, the second lens group LG2 may include a third lens 630 and a fourth lens 640 . The third lens 630 has refractive power. For example, the third lens 630 may have negative refractive power. The third lens 630 has a concave object side surface and a concave image side surface. The third lens 630 may include a spherical surface. For example, both the object side and the image side of the third lens 630 may be formed as spherical surfaces. The fourth lens 640 has refractive power. For example, the fourth lens 640 may have negative refractive power. The fourth lens 640 has a convex object side surface and a concave image side surface. The fourth lens 640 may include an aspheric surface. For example, an image side surface of the fourth lens 640 may be formed as an aspherical surface.

The second reflector P2 and the third reflector P3 may be disposed between the third lens 630 and the image surface IP. The second reflector P2 and the third reflector P3 may be configured to reduce the external distance from the image side surface of the third lens 630 to the image surface IP. In other words, the second reflector P2 and the third reflector P3 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 630 to the image surface, and the third reflector P3 The external distance or size from the image side surface of the lens 630 to the image surface may be reduced. Therefore, the imaging optical system 600 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The second reflector P2 and the third reflector P3 may have a prism shape. However, the shapes of the second and third reflectors P2 and P3 are not limited to prisms.

Next, the shapes of the second reflector P2 and the third reflector P3 will be described.

A cross section of the second reflector P2 may be formed as a triangle having three sides. For example, the cross-sectional shape of the second reflector P2 may be a triangle including a first side P2S1, a second side P2S2, and a third side P2S3.

The second reflector P2 is configured to refract light incident from the third lens 630 to the third reflector P3. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the third lens 630 forms a first transmission surface, and in the cross-sectional shape of the second reflector P2, The third side P2S3 closest to the third reflector P3 may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the second and third sides P2S2 and P2S3 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1, and the second side P2S3 reflects the light reflected from the third side P2S3. A second reflection surface for re-reflecting to the third side P2S3 may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface, the second side P2S2 forms the second reflection surface, and the third side P2S3 ) may form the second transmission surface and the first reflection surface.

A cross section of the third reflector P3 may be formed as a triangle with three sides. For example, the cross-sectional shape of the third reflector P3 may be formed as a triangle including the first side P3S1, the third side P3S2, and the third side P3S3.

The third reflector P3 is configured to form or reflect the light emitted from the second reflector P2 to the upper surface IP. To this end, the third reflector P3 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the third reflector P3 may include two reflective surfaces and two transmission surfaces.

The third reflector P3 may include a plurality of transmission surfaces. For example, the first side P3S1 and the second side P3S2 of the third reflector P3 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the third reflector P3, the first side P3S1 closest to the second reflector P2 forms the first transmission surface, and the cross-sectional shape of the third reflector P3 In , the second side P3S2 closest to the upper surface IP may form a second transmission surface.

The third reflector P3 may include a plurality of reflective surfaces. For example, the first side P3S1, the second side P3S2, and the third side P3S3 of the third reflector P3 may each form a reflective surface. In other words, the second side P3S2 forms a first reflection surface that reflects light incident through the first side P3S1 to the first side P3S1, and the first side P3S1 forms a second side. A second reflection surface that totally reflects light reflected from P3S2 to the third side P3S3 may be formed, and the third side P3S3 may form a third reflection surface that reflects incident light to the upper surface.

That is, in the third reflector P3 according to the present embodiment, the first side P3S1 forms the first transmission surface and the second reflection surface, and the second side P3S2 forms the first reflection surface and the second transmission surface. A surface is formed, and the third side P3S3 may form a third reflective surface.

The second reflector P2 and the third reflector P3 may be configured to establish a predetermined mechanical relationship. For example, the third side P2S3 of the second reflector P2 may be formed substantially parallel to the first side P3S1 of the third reflector P3. As another example, the second side P2S2 of the second reflector P2 may be formed substantially parallel to the second side P3S2 of the third reflector P3. As another example, the angle θ1 between the second side P2S2 and the third side P2S3 of the second reflector P2 is the first side P3S1 and the second side P3S1 of the third reflector P3. It may be substantially the same size as the angle between (θ2) between (P3S2).

The second reflector P2 and the third reflector P3 may be disposed at a predetermined interval. However, the second reflector P2 and the third reflector P3 are not necessarily spaced apart from each other. For example, it may be possible to place one surface of the second reflector P2 and one surface of the third reflector P3 in contact with each other.

Since the imaging optical system 600 configured as above can secure an optical path of considerable length (or distance) through the second reflector P2 and the third reflector P3, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 600 according to this embodiment includes a first lens 610, a second lens 620, a first reflector P1, a third lens 630, a fourth lens 640, a Since the second reflector P2 and the third reflector P3 can be integrated in a limited space, they can be mounted on a small terminal or an ultra-thin terminal.

The imaging optical system 600 configured as above may exhibit aberration characteristics of the form shown in FIG. 20 . Tables 11 and 12 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 10.808 2.000 1.537 55.7 17.1408 S2 -57.895 0.100 S3 2nd lens 28.033 0.800 1.677 19.2 -64.2269 S4 16.847 1.000 S5 Infinity 0.000 S6 1st reflector Infinity 3.000 1.518 64.2 S7 Infinity 3.000 1.518 64.2 S8 Infinity 1.400 S9 3rd lens 129.079544 0.400 1.645 23.5 -117.0044 S10 -181.631 0.200 S11 4th lens -27.3053294 0.800 1.537 55.7 -52.1855 S12 -13.6857342 0.400 S13 2nd reflector Infinity 4.400 1.518 64.2 S14 Infinity 3.200 1.518 64.2 S15 Infinity 1.600 1.518 64.2 S16 Infinity 0.600 S17 3rd reflector Infinity 2.000 1.518 64.2 S18 Infinity 4.000 1.518 64.2 S19 Infinity 6.000 1.518 64.2 S20 Infinity 3.500 1.518 64.2 S21 Infinity 0.500 S22 filter Infinity 0.210 1.518 64.2 S23 Infinity 1.141 S24 upper face Infinity 0.000

side number S1 S2 S3 S4 S9 S10 S11 S12 K 0 0 2.879E+01 1.452E+00 0 0 0 1.035E+01 A 0 0 3.432E-02 7.038E-03 0 0 0 -3.764E-03 B 0 0 -4.297E-03 4.538E-03 0 0 0 1.158E-03 C 0 0 1.513E-03 1.707E-04 0 0 0 -3.614E-04 D 0 0 7.904E-04 7.891E-04 0 0 0 3.850E-05 E 0 0 4.802E-04 9.102E-04 0 0 0 9.442E-06 F 0 0 -7.809E-04 -4.432E-04 0 0 0 2.737E-05 G 0 0 -1.845E-04 -8.055E-06 0 0 0 1.902E-05 H 0 0 0 0 0 0 0 0 J 0 0 0 0 0 0 0 0

Next, an imaging optical system according to a seventh embodiment will be described with reference to FIG. 21 .

The imaging optical system 700 according to the present embodiment includes a first lens group LG1, a first reflector P1, a second lens group LG2, a second reflector P2, It includes a third reflector (P2). However, the configuration of the imaging optical system 700 is not limited to the members described above.

The first lens group LG1 may include a plurality of lenses. For example, the first lens group LG1 may include a first lens 710 and a second lens 720 . However, the configuration of the first lens group LG1 is not limited to the first lens 710 and the second lens 720 . The first lens 710 and the second lens 720 may be sequentially disposed from the object side. The first lens 710 and the second lens 720 may be disposed at a predetermined interval. For example, an image side surface of the first lens 710 may be disposed so as not to face an object side surface of the second lens 720 .

Next, characteristics of the first lens 710 and the second lens 720 will be described.

The first lens 710 has refractive power. For example, the first lens 710 may have positive refractive power. The first lens 710 has a shape in which an object side surface is convex and an image side surface is convex. The first lens 710 may include a spherical surface. For example, both the object side and the image side of the first lens 710 may be formed as spherical surfaces.

The second lens 720 has refractive power. For example, the second lens 720 may have negative refractive power. The second lens 720 has a convex object side surface and a concave image side surface. The second lens 720 may include an aspheric surface. For example, both the object side surface and the image side surface of the second lens 720 may be formed as aspheric surfaces.

The first reflector P1 may be configured to totally reflect light incident through the first lens group LG1 to the second lens group LG2. For example, the first reflector P1 may be configured to reflect light incident through the first lens group LG1 in a direction of approximately 90 degrees.

The second lens group LG2 may include two lenses. For example, the second lens group LG2 may include a third lens 730 and a fourth lens 740 . The third lens 730 has refractive power. For example, the third lens 730 may have negative refractive power. The third lens 730 has a convex object side surface and a concave image side surface. The third lens 730 may include a spherical surface. For example, both the object side and the image side of the third lens 730 may be formed as spherical surfaces. The fourth lens 740 has refractive power. For example, the fourth lens 740 may have negative refractive power. The fourth lens 740 has a convex object side surface and a concave image side surface. The fourth lens 740 may include an aspheric surface. For example, an image side surface of the fourth lens 740 may be formed as an aspherical surface.

The second reflector P2 and the third reflector P3 may be disposed between the third lens 730 and the image surface IP. The second reflector P2 and the third reflector P3 may be configured to reduce the external distance from the image side surface of the third lens 730 to the image surface IP. In other words, the second reflector P2 and the third reflector P3 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 730 to the image surface, and the third reflector P3 The external distance or size from the image side surface of the lens 730 to the image surface may be reduced. Accordingly, the imaging optical system 700 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The second reflector P2 and the third reflector P3 may have a prism shape. However, the shapes of the second and third reflectors P2 and P3 are not limited to prisms.

Next, the shapes of the second reflector P2 and the third reflector P3 will be described.

A cross section of the second reflector P2 may be formed as a triangle having three sides. For example, the cross-sectional shape of the second reflector P2 may be a triangle including a first side P2S1, a second side P2S2, and a third side P2S3.

The second reflector P2 is configured to refract light incident from the third lens 730 to the third reflector P3. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the third lens 730 forms a first transmission surface, and in the cross-sectional shape of the second reflector P2, The third side P2S3 closest to the third reflector P3 may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the second and third sides P2S2 and P2S3 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1, and the second side P2S3 reflects the light reflected from the third side P2S3. A second reflection surface for re-reflecting to the third side P2S3 may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface, the second side P2S2 forms the second reflection surface, and the third side P2S3 ) may form the second transmission surface and the first reflection surface.

A cross section of the third reflector P3 may be formed as a triangle with three sides. For example, the cross-sectional shape of the third reflector P3 may be formed as a triangle including the first side P3S1, the third side P3S2, and the third side P3S3.

The third reflector P3 is configured to form or reflect the light emitted from the second reflector P2 to the upper surface IP. To this end, the third reflector P3 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the third reflector P3 may include two reflective surfaces and two transmission surfaces.

The third reflector P3 may include a plurality of transmission surfaces. For example, the first side P3S1 and the second side P3S2 of the third reflector P3 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the third reflector P3, the first side P3S1 closest to the second reflector P2 forms the first transmission surface, and the cross-sectional shape of the third reflector P3 In , the second side P3S2 closest to the upper surface IP may form a second transmission surface.

The third reflector P3 may include a plurality of reflective surfaces. For example, the first side P3S1, the second side P3S2, and the third side P3S3 of the third reflector P3 may each form a reflective surface. In other words, the second side P3S2 forms a first reflection surface that reflects light incident through the first side P3S1 to the first side P3S1, and the first side P3S1 forms a second side. A second reflection surface that totally reflects light reflected from P3S2 to the third side P3S3 may be formed, and the third side P3S3 may form a third reflection surface that reflects incident light to the upper surface.

That is, in the third reflector P3 according to the present embodiment, the first side P3S1 forms the first transmission surface and the second reflection surface, and the second side P3S2 forms the first reflection surface and the second transmission surface. A surface is formed, and the third side P3S3 may form a third reflective surface.

The second reflector P2 and the third reflector P3 may be configured to establish a predetermined mechanical relationship. For example, the third side P2S3 of the second reflector P2 may be formed substantially parallel to the first side P3S1 of the third reflector P3. As another example, the second side P2S2 of the second reflector P2 may be formed substantially parallel to the second side P3S2 of the third reflector P3. As another example, the angle θ1 between the second side P2S2 and the third side P2S3 of the second reflector P2 is the first side P3S1 and the second side P3S1 of the third reflector P3. It may be substantially the same size as the angle between (θ2) between (P3S2).

The second reflector P2 and the third reflector P3 may be disposed at a predetermined interval. However, the second reflector P2 and the third reflector P3 are not necessarily spaced apart from each other. For example, it may be possible to place one surface of the second reflector P2 and one surface of the third reflector P3 in contact with each other.

Since the imaging optical system 700 configured as above can secure an optical path of considerable length (or distance) through the second reflector P2 and the third reflector P3, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 700 according to this embodiment includes a first lens 710, a second lens 720, a first reflector P1, a third lens 730, a fourth lens 740, a Since the second reflector P2 and the third reflector P3 can be integrated in a limited space, they can be mounted on a small terminal or an ultra-thin terminal.

The imaging optical system 700 configured as above may exhibit aberration characteristics of the form shown in FIG. 22 . Tables 13 and 14 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 10.808 2.000 1.537 55.7 17.1312 S2 -57.680 0.100 S3 2nd lens 28.097 0.800 1.677 19.2 -56.1615 S4 15.971 1.000 S5 Infinity 0.000 S6 1st reflector Infinity 3.000 1.518 64.2 S7 Infinity 3.000 1.518 64.2 S8 Infinity 1.400 S9 3rd lens -51.4637 0.400 1.537 55.7 -249.6500 S10 -37.083 0.200 S11 4th lens -32.1572 0.800 1.537 55.7 -48.2648 S12 -14.2235 0.400 S13 2nd reflector Infinity 4.400 1.518 64.2 S14 Infinity 3.200 1.518 64.2 S15 Infinity 1.600 1.518 64.2 S16 Infinity 0.600 S17 3rd reflector Infinity 2.000 1.518 64.2 S18 Infinity 4.000 1.518 64.2 S19 Infinity 6.000 1.518 64.2 S20 Infinity 3.500 1.518 64.2 S21 Infinity 0.500 S22 filter Infinity 0.210 1.518 64.2 S23 Infinity 1.682 S24 upper face Infinity 0.000

side number S1 S2 S3 S4 S9 S10 S11 S12 K 0 0 2.877E+01 1.465E+00 0 0 0 1.036E+01 A 0 0 3.441E-02 6.928E-03 0 0 0 -3.750E-03 B 0 0 -4.242E-03 4.469E-03 0 0 0 1.063E-03 C 0 0 1.523E-03 1.653E-04 0 0 0 -3.874E-04 D 0 0 7.978E-04 7.791E-04 0 0 0 2.816E-05 E 0 0 4.830E-04 9.062E-04 0 0 0 8.484E-07 F 0 0 -7.728E-04 -4.393E-04 0 0 0 1.956E-05 G 0 0 -1.731E-04 -7.472E-06 0 0 0 2.167E-05 H 0 0 0 0 0 0 0 0 J 0 0 0 0 0 0 0 0

Next, an imaging optical system according to an eighth embodiment will be described with reference to FIG. 23 .

The imaging optical system 800 according to the present embodiment includes a first lens group LG1, a first reflector P1, a second lens group LG2, a second reflector P2, It includes a third reflector (P2). However, the configuration of the imaging optical system 800 is not limited to the members described above.

The first lens group LG1 may include a plurality of lenses. For example, the first lens group LG1 may include a first lens 810 and a second lens 820 . However, the configuration of the first lens group LG1 is not limited to the first lens 810 and the second lens 820 . The first lens 810 and the second lens 820 may be sequentially disposed from the object side. The first lens 810 and the second lens 820 may be disposed at a predetermined interval. For example, an image side surface of the first lens 810 may be disposed so as not to face an object side surface of the second lens 820 .

Next, characteristics of the first lens 810 and the second lens 820 will be described.

The first lens 810 has refractive power. For example, the first lens 810 may have positive refractive power. The first lens 810 has a shape in which an object side surface is convex and an image side surface is convex. The first lens 810 may include a spherical surface. For example, both the object side and the image side of the first lens 810 may be formed as spherical surfaces.

The second lens 820 has refractive power. For example, the second lens 820 may have negative refractive power. The second lens 820 has a convex object side surface and a concave image side surface. The second lens 820 may include an aspherical surface. For example, both the object side and the image side of the second lens 820 may be formed as aspheric surfaces.

The first reflector P1 may be configured to totally reflect light incident through the first lens group LG1 to the second lens group LG2. For example, the first reflector P1 may be configured to reflect light incident through the first lens group LG1 in a direction of approximately 90 degrees.

The second lens group LG2 may include three lenses. For example, the second lens group LG2 may include a third lens 830 , a fourth lens 840 , and a fifth lens 850 . The third lens 830 has refractive power. For example, the third lens 830 may have negative refractive power. The third lens 830 has a concave object side surface and a convex image side surface. The third lens 830 may include a spherical surface. For example, both the object side and the image side of the third lens 830 may be formed as spherical surfaces. The fourth lens 840 has refractive power. For example, the fourth lens 840 may have negative refractive power. The object side of the fourth lens 840 is concave and the image side is flat. The fourth lens 840 may include a spherical surface. For example, both the object side and the image side of the fourth lens 840 may be formed as spherical surfaces. The fifth lens 850 has refractive power. For example, the fifth lens 850 may have negative refractive power. The fifth lens 850 has a convex object side surface and a concave image side surface. The fifth lens 850 may include an aspherical surface. For example, an image side surface of the fifth lens 850 may be formed as an aspherical surface.

The second reflector P2 and the third reflector P3 may be disposed between the third lens 830 and the image surface IP. The second reflector P2 and the third reflector P3 may be configured to reduce the external distance from the image side surface of the third lens 830 to the image surface IP. In other words, the second reflector P2 and the third reflector P3 do not substantially change the optical path length (or BFL) from the image side surface of the third lens 830 to the image surface, and the third reflector P3 The external distance or size from the image side surface of the lens 830 to the image surface may be reduced. Accordingly, the imaging optical system 800 according to the present embodiment may be installed in a small terminal or a thin terminal as it is optically designed. The second reflector P2 and the third reflector P3 may have a prism shape. However, the shapes of the second and third reflectors P2 and P3 are not limited to prisms.

Next, the shapes of the second reflector P2 and the third reflector P3 will be described.

A cross section of the second reflector P2 may be formed as a triangle having three sides. For example, the cross-sectional shape of the second reflector P2 may be a triangle including a first side P2S1, a second side P2S2, and a third side P2S3.

The second reflector P2 is configured to refract light incident from the third lens 830 to the third reflector P3. To this end, the second reflector P2 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the second reflector P2 may include two reflective surfaces and two transmission surfaces.

The second reflector P2 may include a plurality of transmission surfaces. For example, the first side P2S1 and the third side P2S3 of the second reflector P2 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the second reflector P2, the first side P2S1 closest to the third lens 830 forms a first transmission surface, and in the cross-sectional shape of the second reflector P2, The third side P2S3 closest to the third reflector P3 may form a second transmission surface.

The second reflector P2 may include a plurality of reflective surfaces. For example, the second and third sides P2S2 and P2S3 of the second reflector P2 may form the first and second reflection surfaces, respectively. In other words, the third side P2S3 forms a first reflection surface that reflects light incident through the first side P2S1, and the second side P2S3 reflects the light reflected from the third side P2S3. A second reflection surface for re-reflecting to the third side P2S3 may be formed.

That is, in the second reflector P2 according to the present embodiment, the first side P2S1 forms the first transmission surface, the second side P2S2 forms the second reflection surface, and the third side P2S3 ) may form the second transmission surface and the first reflection surface.

A cross section of the third reflector P3 may be formed as a triangle with three sides. For example, the cross-sectional shape of the third reflector P3 may be formed as a triangle including the first side P3S1, the third side P3S2, and the third side P3S3.

The third reflector P3 is configured to form or reflect the light emitted from the second reflector P2 to the upper surface IP. To this end, the third reflector P3 may include a plurality of reflective surfaces and a plurality of transmission surfaces. In other words, the third reflector P3 may include two reflective surfaces and two transmission surfaces.

The third reflector P3 may include a plurality of transmission surfaces. For example, the first side P3S1 and the second side P3S2 of the third reflector P3 may form a first transmission surface and a second transmission surface, respectively. In other words, in the cross-sectional shape of the third reflector P3, the first side P3S1 closest to the second reflector P2 forms the first transmission surface, and the cross-sectional shape of the third reflector P3 In , the second side P3S2 closest to the upper surface IP may form a second transmission surface.

The third reflector P3 may include a plurality of reflective surfaces. For example, the first side P3S1, the second side P3S2, and the third side P3S3 of the third reflector P3 may each form a reflective surface. In other words, the second side P3S2 forms a first reflection surface that reflects light incident through the first side P3S1 to the first side P3S1, and the first side P3S1 forms a second side. A second reflection surface that totally reflects light reflected from P3S2 to the third side P3S3 may be formed, and the third side P3S3 may form a third reflection surface that reflects incident light to the upper surface.

That is, in the third reflector P3 according to the present embodiment, the first side P3S1 forms the first transmission surface and the second reflection surface, and the second side P3S2 forms the first reflection surface and the second transmission surface. A surface is formed, and the third side P3S3 may form a third reflective surface.

The second reflector P2 and the third reflector P3 may be configured to establish a predetermined mechanical relationship. For example, the third side P2S3 of the second reflector P2 may be formed substantially parallel to the first side P3S1 of the third reflector P3. As another example, the second side P2S2 of the second reflector P2 may be formed substantially parallel to the second side P3S2 of the third reflector P3. As another example, the angle θ1 between the second side P2S2 and the third side P2S3 of the second reflector P2 is the first side P3S1 and the second side P3S1 of the third reflector P3. It may be substantially the same size as the angle between (θ2) between (P3S2).

The second reflector P2 and the third reflector P3 may be disposed at a predetermined interval. However, the second reflector P2 and the third reflector P3 are not necessarily spaced apart from each other. For example, it may be possible to place one surface of the second reflector P2 and one surface of the third reflector P3 in contact with each other.

Since the imaging optical system 800 configured as above can secure an optical path of considerable length (or distance) through the second reflector P2 and the third reflector P3, it is necessary to implement a high-performance telephoto camera module. can be hired In addition, the imaging optical system 800 according to this embodiment includes a first lens 810, a second lens 820, a first reflector P1, a third lens 830, a fourth lens 840, Since the 5 lenses 850, the second reflector P2, and the third reflector P3 can be integrated in a limited space, they can be mounted on a small terminal or an ultra-thin terminal.

The imaging optical system 800 configured as above may exhibit aberration characteristics of the form shown in FIG. 24 . Tables 15 and 16 show lens characteristics and aspheric surface values of the imaging optical system according to the present embodiment.

side number composition radius of curvature thickness/distance refractive index Abe number focal length S1 1st lens 10.807 2.000 1.537 55.7 17.1673 S2 -58.514 0.100 S3 2nd lens 27.959 0.800 1.677 19.2 -83.6514 S4 18.501 1.000 S5 Infinity 0.000 S6 1st reflector Infinity 3.000 1.518 64.2 S7 Infinity 3.000 1.518 64.2 S8 Infinity 0.800 S9 3rd lens 22.4705 0.400 1.646 23.5 -127.8761 S10 31.081 0.100 S11 4th lens 57.5181 0.400 1.646 23.5 -88.9736 S12 Infinity 0.200 S13 5th lens -19.2307 0.400 1.518 64.2 -82.9800 S14 -13.1942 0.400 1.518 64.2 S15 2nd reflector Infinity 4.400 1.518 64.2 S16 Infinity 3.200 S17 Infinity 1.600 1.518 64.2 S18 Infinity 0.600 1.518 64.2 S19 3rd reflector Infinity 2.000 1.518 64.2 S20 Infinity 4.000 1.518 64.2 S21 Infinity 6.000 S22 Infinity 3.500 1.518 64.2 S23 Infinity 0.500 S24 filter Infinity 0.210 S25 Infinity 1.556 S26 upper face Infinity 0.000

side number S1 S2 S3 S4 S9 S10 S11 S12 S13 S14 K 0 0 2.864E+01 1.462E+00 0 0 0 0 0 1.025E+01 A 0 0 3.436E-02 6.873E-03 0 0 0 0 0 -5.507E-03 B 0 0 -4.679E-03 4.923E-03 0 0 0 0 0 1.926E-03 C 0 0 1.442E-03 7.499E-07 0 0 0 0 0 -2.913E-04 D 0 0 9.654E-04 8.854E-04 0 0 0 0 0 -6.461E-05 E 0 0 4.035E-04 1.210E-03 0 0 0 0 0 1.122E-04 F 0 0 -7.092E-04 -6.263E-04 0 0 0 0 0 9.219E-05 G 0 0 -2.294E-04 1.773E-04 0 0 0 0 0 6.168E-05 H 0 0 0 0 0 0 0 0 0 0 J 0 0 0 0 0 0 0 0 0 0

The imaging optical system according to the above-described embodiment may satisfy all of the above-mentioned conditional expressions. Table 17 shows optical characteristic values and conditional expression values of imaging optical systems according to the first to eighth embodiments.

note Example 1 Example 2 3rd embodiment Example 4 Example 5 6th embodiment Example 7 Example 8 f 24.8379 26.0002 26.0862 28.0032 19.1383 33.9955 34.3373 34.0000 f number 3.18 3.69 3.45 2.87 3.92 3.92 3.84 3.18 TTL 30.2842 31.1208 30.8560 37.0649 24.2809 40.2514 40.7917 40.1660 BFL 1.1136 1.1482 5.3834 0.6649 0.0000 1.3514 1.8917 1.7660 V1-V2 33.5098 33.5098 32.1121 36.4792 36.4792 36.4792 36.4792 36.4792 TTL/f 1.2193 1.1969 1.1828 1.3236 1.2687 1.1840 1.1880 1.1814 BFL/TTL 0.8028 0.8241 0.8226 0.6735 0.7010 0.6845 0.6887 0.6963 TTL/f1 3.1779 3.2398 3.0169 2.1712 2.3603 2.3483 2.3811 2.3397 TTL/f2 -4.1066 -4.3864 -4.3577 -0.7587 -0.7667 -0.6267 -0.7263 -0.4802 TTL/f3 1.5141 1.6729 1.9380 -0.3274 -0.7354 -0.3440 -0.1634 -0.3141 (f number*f)
/TTL 2.6081 3.0829 2.9167 2.1683 3.0898 3.3108 3.2324 2.6918 Vh1/TTL 0.2830 0.3044 0.2746 0.1862 0.1705 0.1714 0.1692 0.1718 Vh2/TTL 0.1954 0.2194 0.1888 0.1295 0.1186 0.1193 0.1177 0.1195

The present invention is not limited to the embodiments described above, and those skilled in the art can do so without departing from the gist of the technical idea of the present invention described in the claims below. It can be implemented by making various changes. For example, various features described in the above-described embodiment may be applied in combination with other embodiments unless explicitly stated otherwise.

Claims (16)

a first lens group;
first optical path changing means including a plurality of reflecting surfaces; and
second optical path changing means including a plurality of reflective surfaces;
including,
the first lens group, the first light path changing means, and the second light path changing means are sequentially disposed from the object side;
An imaging optical system that satisfies the following conditional expression.
2.0 < TTL/f1 < 4.0
(In the above conditional expression, TTL is the distance from the side of the object to the image plane of the frontmost lens (first lens) of the first lens group, and f1 is the focal length of the first lens) According to claim 1,
The first optical path conversion means,
a first rearmost reflective surface disposed closest to the second optical path changing means; and
and a first reflection surface configured to re-reflect the light reflected from the first rearmost reflection surface to the second optical path changing unit. According to claim 2,
The first optical path conversion means,
The imaging optical system further includes a first frontmost reflecting surface configured to reflect the light emitted from the first lens group to the first rearmost reflecting surface. According to claim 2,
The second optical path conversion means
a second frontmost reflective surface disposed most adjacent to the first optical path changing means; and
and a second reflective surface configured to reflect light emitted from the first reflective surface to the second frontmost reflective surface. According to claim 4,
The second optical path conversion means,
and a second rearmost reflective surface configured to reflect the light emitted from the second most forward reflective surface to an image surface. According to claim 4,
An angle of interception between the first rearmost reflective surface and the first reflective surface has the same size as an angle of interception between the second most rearward reflective surface and the second reflective surface. According to claim 1,
The first lens group,
An imaging optical system including a lens having positive refractive power. According to claim 1,
The imaging optical system further includes a third optical path changing means disposed on an object side of the first optical path changing means. According to claim 8,
and a second lens group disposed between the third optical path changing means and the first optical path changing means. lens group;
first optical path changing means including a plurality of reflecting surfaces; and
second optical path changing means including a plurality of reflective surfaces;
including,
the first lens group, the first light path changing means, and the second light path changing means are sequentially disposed from the object side;
wherein each of the first optical path changing means and the second optical path changing means includes one total reflection surface. According to claim 10,
The lens group,
a first lens having positive refractive power; and
a second lens having negative refractive power;
Imaging optical system comprising a. According to claim 11,
An imaging optical system that satisfies the following conditional expression.
30 < V1-V2
(In the conditional expression, V1 is the Abbe number of the first lens, and V2 is the Abbe number of the second lens) According to claim 11,
An imaging optical system that satisfies the following conditional expression.
2.0 < TTL/f1 < 4.0
(In the above conditional expression, TTL is the distance from the side of the object to the image surface of the first lens, and f1 is the focal length of the first lens) According to claim 11,
An imaging optical system that satisfies the following conditional expression.
-5.0 < TTL/f2 < -0.2
(In the above conditional expression, TTL is the distance from the side of the object to the image surface of the first lens, and f2 is the focal length of the second lens) According to claim 10,
An imaging optical system that satisfies the following conditional expression.
1.1 < TTL/f
(In the above conditional expression, TTL is the distance from the object side of the frontmost lens of the lens group to the image plane, and f is the focal length of the imaging optical system) According to claim 10,
An imaging optical system that satisfies the following conditional expression.
0.6 < BFL/TTL < 0.9
(In the conditional expression, BFL is the distance from the image side of the rearmost lens of the lens group to the image plane, and TTL is the distance from the object side of the frontmost lens of the lens group to the image plane)

Images