Optical image capturing system

Abstract

An optical imaging system includes: a lens group including at least one lens forming a first optical axis; and an optical path converter that reflects the light emitted from the lens group to form an image on the imaging plane. In the optical imaging system, a maximum distance from an object-side surface of a foremost lens disposed closest to an object side among the lens groups to an imaging surface in a first optical axis direction is 12.0 mm or less.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority from Korean Patent Application No. 10-2021-0134820 filed on October 12, 2021, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] The present disclosure relates to an optical imaging system and an optical imaging system including one or more optical path converters. Background Art

[0004] Portable electronic devices may include camera modules. For example, portable electronic devices such as notebook computers, smart phones, etc. may include camera modules for video conferencing, video calls, etc. At the same time, as the performance of portable electronic devices improves, the demand for camera modules with high resolution is also increasing. For example, the image sensor of the camera module is gradually enlarged to facilitate high resolution. However, since the enlargement of the image sensor increases the total length of the optical imaging system constituting the camera module (i.e., the distance from the object side of the front lens to the imaging surface), there may be a problem of miniaturization and thinning of the camera module.

[0005] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applicable as prior art to the present disclosure. Summary of the invention

[0006] The present invention summary section is provided to introduce a selection of inventive concepts in a concise form, and these inventive concepts will be further described in the following detailed description section. The present invention summary section is not intended to identify the key features or essential features of the claimed subject matter, nor is it used to help determine the scope of the claimed subject matter.

[0007] In a general aspect, an optical imaging system includes: a lens group including at least one lens forming a first optical axis; and an optical path converter reflecting light emitted from the lens group to form an image on an imaging plane, wherein a maximum distance from an object side surface of a frontmost lens disposed closest to the object side in the lens group to the imaging plane in the direction of the first optical axis is 11.0 mm or less.

[0008] The lens group may include a first lens, a second lens, and a third lens arranged sequentially from the object side.

[0009] The first lens may have positive refractive power.

[0010] The second lens may have negative refractive power.

[0011] The second lens may have a concave object side surface.

[0012] The second lens may have a concave image side surface.

[0013] The third lens may have a positive refractive power.

[0014] The distance of the optical path from the image side surface of the last lens, which is the closest to the imaging surface among the lens group, to the imaging surface may be 20.0 mm to 50.0 mm.

[0015] The following conditional expression 0.86 < BFL / TTL < 0.96 may be satisfied, where TTL is the distance of the optical path from the object side surface of the frontmost lens to the imaging surface, and BFL is the distance of the optical path from the image side surface of the last lens among the lens group to the imaging surface.

[0016] The optical axis in the first optical axis direction and the optical axis of the imaging surface may be substantially parallel.

[0017] In another general aspect, an optical imaging system includes: a lens group including at least one lens; and an optical path converter disposed between the lens group and the imaging surface and configured to reflect the light emitted from the lens group one or more times to form an image on the imaging surface by the light, where 8 < f / IMG HT < 12, where f is the focal length of the optical imaging system, and IMG HT is the height of the imaging surface.

[0018] The following conditional expression 0.30 < f1 / f < 0.40 may be satisfied, where f1 is the focal length of the first lens.

[0019] The following conditional expression -0.28 < f2 / f < -0.18 may be satisfied, where f2 is the focal length of the second lens.

[0020] The following conditional expression 0.40 < f3 / f < 0.50 may be satisfied, where f3 is the focal length of the third lens.

[0021] The following conditional expression 1.68 < (Nd1 + Nd2 + Nd3) / 3 < 1.74 may be satisfied, where Nd1 is the refractive index of the first lens, Nd2 is the refractive index of the second lens, and Nd3 is the refractive index of the third lens.

[0022] The maximum distance from the object side surface of the frontmost lens, which is the closest to the object side among the lens group, to the imaging surface in the optical axis direction of the lens group may be 11.0 mm or less.

[0023] In another general aspect, an optical imaging system includes: a lens group including at least one lens; and an optical path converter disposed between the lens group and an imaging surface and configured to reflect light emitted from the lens group two or more times to form an image on the imaging surface by the light, where 1.0 < BFL / f < 1.6, where f is the focal length of the optical imaging system and BFL is the distance of the optical path from the image side surface of the last lens among the lens group to the imaging surface.

[0024] The optical axis of at least one lens and the optical axis of the imaging surface may be substantially parallel.

[0025] Other features and aspects will be apparent from the accompanying drawings, the claims, and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a configuration diagram of an optical imaging system according to a first embodiment of the present disclosure.

[0027] Figure 2 and Figure 3 is Figure 1 the aberration curve of the optical imaging system shown in

[0028] Figure 4 is a configuration diagram of an optical imaging system according to a second embodiment of the present disclosure.

[0029] Figure 5 is Figure 4 the aberration curve of the optical imaging system shown in

[0030] Figure 6 is a configuration diagram of an optical imaging system according to a third embodiment of the present disclosure.

[0031] Figure 7 is Figure 6 the aberration curve of the optical imaging system shown in

[0032] Figure 8 is a configuration diagram of an optical imaging system according to a fourth embodiment of the present disclosure.

[0033] Fig. 9 is Figure 8 the aberration curve of the optical imaging system shown in

[0034] Fig.10 is a configuration diagram of an optical imaging system according to a fifth embodiment of the present disclosure.

[0035] Fig.11 is schematically a view showing the optical paths of a first optical path converter and a second optical path converter according to Fig.10 that shown in

[0036] Fig.12 yes Fig.10 Aberration curves of the optical imaging system shown in .

[0037] Fig.13 is a perspective view of a portable electronic device including an optical imaging system according to an embodiment of the present disclosure.

[0038] Throughout the drawings and detailed description, the same reference numerals denote the same elements. The drawings may not be drawn to scale, and the relative sizes, proportions, and depictions of the elements in the drawings may be exaggerated for clarity, illustration, and convenience. DETAILED DESCRIPTION

[0039] Hereinafter, although exemplary embodiments of the present disclosure are described in detail with reference to the accompanying illustrative drawings, it should be noted that examples are not limited thereto.

[0040] In the following description of the present disclosure, terms related to components of the present disclosure may be named in consideration of the function of each component and should not be construed as limiting the meaning of the technical components of the present disclosure.

[0041] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described in this application. However, various changes, modifications and equivalents of the methods, devices and / or systems described in this application will be apparent after understanding the present disclosure. For example, the order of operations described in this application is merely an example, and except for operations that must occur in a specific order, it is not limited to the order set forth in this application, but can be changed, which will be apparent after understanding the present disclosure. In addition, for greater clarity and brevity, the description of features well known in the art may be omitted.

[0042] The features described in this application can be implemented in different forms and should not be understood as being limited to the examples described in this application. Rather, the examples described in this application are provided only to illustrate some of the many possible ways to implement the methods, devices and / or systems described in this application, which will be apparent after understanding this disclosure.

[0043] It should be noted that in this application, the use of the word "may" with respect to examples or embodiments, for example, regarding what an example or embodiment may include or implement, means that there is at least one example or embodiment that includes or implements such features, and all examples and embodiments are not limited thereto.

[0044] Throughout the specification, when an element such as a layer, a region, or a substrate is described as being “on,” “connected to,” or “coupled to” another element, the element may be directly “on,” “connected to,” or “coupled to” the other element, or one or more other elements may be present between the element and the other element. Conversely, when an element is described as being “directly on,” “directly connected to,” or “directly coupled to” another element, there are no other elements between the element and the other element.

[0045] As used in this application, the term "and / or" includes any one of the associated listed items and any combination of any two or more items; similarly, "at least one of..." includes any one of the associated listed items and any combination of any two or more items.

[0046] Although the terms "first", "second" and "third" may be used in this application to describe various members, components, regions, layers or parts, these members, components, regions, layers or parts are not limited by these terms. More specifically, these terms are only used to distinguish one member, component, region, layer or part from another member, component, region, layer or part. Therefore, without departing from the teachings of the examples described in this application, the first member, first component, first region, first layer or first part mentioned in these examples may also be referred to as the second member, second component, second region, second layer or second part.

[0047] Spatially relative terms such as "above", "higher", "below", and "lower" may be used in this application for descriptive convenience to describe the relationship of one element relative to another element as shown in the accompanying drawings. In addition to covering the orientations depicted in the accompanying drawings, these spatially relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the accompanying drawings is flipped, an element described as being "above" or "higher" relative to another element will be "below" or "lower" relative to the other element. Therefore, depending on the spatial orientation of the device, the term "above" covers both orientations of "above" and "below". The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative terms used in this application should be interpreted accordingly.

[0048] The terms used in this application are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the articles "a", "an" and "the" are intended to also include plural forms. The words "include", "comprise" and "have" indicate the presence of the features, numbers, operations, components, elements and / or combinations thereof described, but do not exclude the presence or addition of one or more other features, numbers, operations, components, elements and / or combinations thereof.

[0049] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described in the present application are not limited to the specific shapes shown in the drawings, but include variations in shapes that occur during manufacturing.

[0050] The features of the examples described in this application may be combined in various ways that will be apparent after gaining an understanding of the present disclosure. In addition, although the examples described in this application have various configurations, other configurations that will be apparent after understanding the present disclosure are also possible.

[0051] An aspect of the present disclosure is to provide an optical imaging system that can be mounted on a portable electronic device regardless of the size of an image sensor and the optical path length of the optical imaging system.

[0052] In addition, in this specification, the first lens represents the lens closest to the object (or subject), and the third lens represents the lens closest to the imaging surface (or image sensor). In this specification, the units of the radius of curvature, thickness, TTL (the distance of the optical path from the object side of the first lens to the imaging surface), IMG HT (the height of the imaging surface), and focal length are expressed in millimeters (mm). In addition, the thickness of the lens, the distance between the lenses, TTL, BFL (the distance of the optical path from the image side of the last lens closest to the image sensor to the imaging surface), and the optical path can be the distance measured based on the center of the optical axis of the lens. In addition, in the description of the lens shape, a configuration in which one surface is convex means that the optical axis area of ​​the surface is convex, and a structure in which one surface is concave means that the optical axis area of ​​the surface is concave. Therefore, even when one surface of the lens is described as convex, the edge of the lens can also be concave. Similarly, even when one surface of the lens is described as concave, the edge of the lens can also be convex.

[0053] The optical imaging system described in this specification can be configured to be installed on a portable electronic device. For example, the optical imaging system can be installed on a smart phone, a notebook computer, an augmented reality device, a virtual reality device (VR), a portable game console, etc. The scope of use and examples of the optical imaging system described in this specification are not limited to the above-mentioned electronic devices. For example, the optical imaging system provides a narrow installation space, but can be applied to electronic devices that require high-resolution imaging.

[0054] The optical imaging system according to the first aspect of the present disclosure may include a lens group and an optical path converter. The lens group may include at least one lens. For example, the lens group may include a first lens, a second lens, and a third lens arranged sequentially along the first optical axis from the object side. The number of lenses constituting the lens group is not limited to three. For example, the lens group may include four or more lenses. As another example, the lens group may include two or fewer lenses. The lens group may be configured to form an optical axis. For example, the lenses of the lens group may be arranged sequentially along the first optical axis. The optical path converter may be configured to convert or change the optical path of the optical imaging system. For example, the optical path converter may convert the optical path formed along the first optical axis in a direction intersecting the first optical axis. As a specific example, the optical path converter may convert the optical path to form an image on an imaging surface using light emitted from the lens group.

[0055] The optical imaging system according to the first aspect can be configured to be mounted on a portable electronic device while having an optical path of considerable size. For example, the length of the optical path of the optical imaging system (the distance of the optical path from the object side of the frontmost lens in the lens group to the imaging plane: TTL) can be greater than the thickness of the portable electronic device, but the external height of the optical imaging system can be less than the thickness of the portable electronic device. As a specific example, the maximum distance from the object side of the frontmost lens in the lens group to the imaging plane in the first optical axis direction can be 11.0 mm or less.

[0056] The optical imaging system according to the second aspect may include a lens group and an optical path converter. The lens group may include at least one lens. For example, the lens group may include a first lens, a second lens, and a third lens arranged sequentially along the first optical axis from the object side. The number of lenses constituting the lens group is not limited to three. For example, the lens group may include four or more lenses. As another example, the lens group may include two or fewer lenses. The optical path converter may be disposed between the lens group and the imaging surface, and may be configured to reflect light emitted from the lens group once or more times. For example, the optical path converter may reflect light emitted from the lens group once in a direction intersecting the first optical axis. As another example, the optical path converter may reflect light emitted from the lens group twice in a direction intersecting the first optical axis. As another example, the optical path converter may reflect light emitted from the lens group in a direction intersecting the first optical axis and in a direction parallel to the first optical axis.

[0057] The optical imaging system according to the second aspect can form a specific numerical relationship between the focal length f and the image height IMG HT (the height of the imaging surface). For example, the optical imaging system according to the second aspect can satisfy 8.0 <f / IMG HT<12.0。

[0058] The optical path converter according to the present specification may include a prism. For example, the optical path converter may include a prism or two or more prisms. As another example, the optical path converter may include a Pechan prism or one or more prisms and one or more Pechan prisms. The configuration of the optical path converter is not limited to a prism and a Pechan prism. For example, the optical path converter may include a reflector.

[0059] The optical imaging system according to the present specification may satisfy one or more of the following conditional expressions. For example, the optical imaging system according to the first aspect and the second aspect may satisfy one or more of the following conditional expressions.

[0060] 10.0mm <TOH<12.0mm

[0061] 21.5mm <TOL<32.0mm

[0062] 7.50mm <TOW<16.5mm

[0063] 6.0mm <PEH<7.0mm

[0064] 6.0mm <PEL<8.5mm

[0065] 11.0mm <PEW<13.0mm

[0066] 0.05mm <DPE12

[0067] 0.1mm <DPEP

[0068] 0.2mm <DLRP1<1.0mm

[0069] 5.0mm <P1W<9.0mm

[0070] 5.0mm <P1H<9.0mm

[0071] 0.05mm <DPA

[0072] In the above conditional expressions, TOH is the maximum length of the optical imaging system in the first optical axis direction, TOL is the maximum length of the optical imaging system in the second optical axis direction (in a direction intersecting the first optical axis and extending in the imaging plane direction), TOW is the maximum length of the optical imaging system in the third optical axis direction (in a direction intersecting the first optical axis and the second optical axis, respectively), PEH is the length of the Pekan prism constituting the optical path converter in the first optical axis direction, PEL is the length of the Pekan prism constituting the optical path converter in the second optical axis direction, PEW is the length of the Pekan prism constituting the optical path converter in the third optical axis direction, and DPE12 is the length from the exit surface of the first Pekan prism constituting the optical path converter to the optical path converter constituting the optical path converter. DPEP is the distance between the Pekan prisms constituting the optical path converter (for example, the distance from the exit surface of a prism to the incident surface of a Pekan prism arranged on the image side of the prism, or the distance from the exit surface of the Pekan prism to the incident surface of the prism arranged on the image side of the Pekan prism), DLRP1 is the distance from the image side surface of the last lens in the lens group to the incident surface of the frontmost prism of the optical path converter, P1W is the length of the prisms constituting the optical path converter in the direction of the third optical axis, P1H is the length of the prisms constituting the optical path converter in the direction of the second optical axis, and DPA is the distance from the exit surface of the first prism constituting the optical path converter to the incident surface of the second prism constituting the optical path converter.

[0073] The optical imaging system may satisfy some of the above conditional expressions in a more limited form as follows:

[0074] 0.05mm <DPE12≤0.1mm

[0075] 0.1mm <DPEP<0.6mm

[0076] 0.05mm <DPA≤0.1mm

[0077] The optical imaging system according to the present specification may also satisfy one or more of the following conditional expressions, regardless of the above conditional expressions. As an example, the optical imaging system may satisfy one or more of the following conditional expressions while satisfying one or more of the above conditional expressions. As another example, the optical imaging system may satisfy one or more of the following conditional expressions, regardless of whether the above conditional expressions are satisfied:

[0078] 1.0 <TTL / f<1.7

[0079] 0.86 <BFL / TTL<0.96

[0080] 0.30 <f1 / f<0.40

[0081] -0.28 <f2 / f<-0.18

[0082] 0.40 <f3 / f<0.50

[0083] 1.0 <BFL / f<1.6

[0084] 1.68<(Nd1+Nd2+Nd3) / 3<1.74

[0085] 1.0 <TTL / BFL<1.20

[0086] 20.0mm <BFL<50.0mm

[0087] In the above conditional expressions, TTL is the length of the optical path from the object side surface of the front lens (first lens) of the lens group to the imaging surface, f is the focal length of the optical imaging system, BFL is the distance of the optical path from the image side surface of the last lens (third lens) of the lens group to the imaging surface, 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, Nd1 is the refractive index of the first lens, Nd2 is the refractive index of the second lens, and Nd3 is the refractive index of the third lens.

[0088] The optical imaging system according to the present specification may include one or more lenses having the following characteristics as needed. For example, the optical imaging system according to the first aspect may include one of the first to third lenses according to the following characteristics. As another example, the optical imaging system according to the second aspect may include two or more of the first to third lenses according to the following characteristics. The optical imaging system according to the above aspects may not necessarily include lenses according to the following characteristics. In the following, the characteristics of the first to third lenses will be described.

[0089] The first lens may have a refractive power. For example, the first lens may have a positive refractive power. The first lens may include a spherical surface or an aspherical surface. For example, both surfaces of the first lens may be aspherical. The first lens may be made of a material having high light transmittance and good processability. For example, the first lens may be made of a plastic material or a glass material. The first lens may be configured to have a predetermined refractive index. For example, the refractive index of the first lens may be greater than 1.7. As a specific example, the refractive index of the first lens may be greater than 1.70 and less than 1.80. The first lens may have a predetermined Abbe number. For example, the Abbe number of the first lens may be 40 or greater. As a specific example, the Abbe number of the first lens may be greater than 40 and less than 50.

[0090] The second lens may have a refractive power. For example, the second lens may have a negative refractive power. The second lens may have a shape in which one surface is concave. For example, the second lens may have a concave object side surface. As another example, the second lens may have a concave image side surface. The second lens may include a spherical surface or an aspherical surface. For example, both surfaces of the second lens may be aspherical. The second lens may be made of a material having high light transmittance and good processability. For example, the second lens may be made of a plastic material or a glass material. The second lens may be configured to have a predetermined refractive index. For example, the refractive index of the second lens may be greater than 1.6. As a specific example, the refractive index of the second lens may be greater than 1.60 and less than 1.70. The second lens may have a predetermined Abbe number. For example, the Abbe number of the second lens may be 30 or more. As a specific example, the Abbe number of the second lens may be greater than 20 and less than 40.

[0091] The third lens may have a refractive power. For example, the third lens may have a positive refractive power. The third lens may include a spherical surface or an aspherical surface. For example, both surfaces of the third lens may be aspherical. The third lens may be made of a material having high light transmittance and good processability. For example, the third lens may be made of a plastic material or a glass material. The third lens may be configured to have a predetermined refractive index. For example, the refractive index of the third lens may be greater than 1.7. As a specific example, the refractive index of the third lens may be greater than 1.70 and less than 1.80. The third lens may have a predetermined Abbe number. For example, the Abbe number of the third lens may be 40 or greater. As a specific example, the Abbe number of the third lens may be greater than 40 and less than 50.

[0092] The plurality of lenses may be made of a material having a refractive index different from that of air. For example, the plurality of lenses may be made of a plastic material or a glass material. At least one of the plurality of lenses may have an aspherical shape. The aspherical shape of the lens may be expressed by Equation 1.

[0093] Equation 1

[0094]

[0095] In Equation 1, c is the inverse of the radius of curvature of the corresponding lens, k is the cone constant, r is the distance from any point on the aspherical surface to the optical axis, A to H and J are aspherical constants, and Z (or SAG) is the height from a specific point on the aspherical surface to the vertex of the corresponding aspherical surface in the optical axis direction.

[0096] The optical imaging system according to the present specification may include a filter and an aperture.

[0097] The filter can be arranged between the lens group and the optical path converter, or between the optical path converter and the imaging surface. The filter can block incident light of some wavelengths to improve the resolution of the optical imaging system. For example, the filter can block incident light of infrared wavelengths. The diaphragm can be arranged between the lenses, or between the lens group and the optical path converter. The diaphragm can be omitted as needed.

[0098] The optical imaging system according to the present specification may further include a spacing member. The spacing member may be disposed between lenses, between a lens group and an optical path converter, or between an optical path converter and an imaging surface.

[0099] Next, specific embodiments of the optical imaging system will be described with reference to the accompanying drawings.

[0100] First, refer to Figure 1 An optical imaging system 100 according to a first embodiment is described.

[0101] The optical imaging system 100 may include a lens group LG and an optical path converter FE. The configuration of the optical imaging system 100 is not limited to the lens group LG and the optical path converter FE. For example, the optical imaging system 100 may further include a filter IF disposed between the optical path converter FE and the imaging plane IP.

[0102] The lens group LG may include a plurality of lenses. For example, the lens group LG may include a first lens 110, a second lens 120, and a third lens 130 arranged sequentially from the object side. The configuration of the lens group LG is not limited to the first lens 110 to the third lens 130. For example, the lens group LG may consist of only the first lens 110 and the second lens 120. As another example, the lens group LG may be configured to include the first lens 110 to the fourth lens (not shown).

[0103] The first lens 110 may have positive refractive power. The first lens 110 may have a convex object-side surface and a convex image-side surface. The second lens 120 may have negative refractive power. The second lens 120 may have a concave object-side surface and a concave image-side surface. The third lens 130 may have positive refractive power. The third lens 130 may have a convex object-side surface and a convex image-side surface.

[0104] The optical path converter FE may include a prism P. The prism P may be disposed between the lens group LG and the imaging surface IP. The prism P may be configured to convert the optical path of the lens group LG. For example, the prism P may convert the path of light incident along the first optical axis C1 in the direction of the second optical axis C2.

[0105] Table 1 shows lens characteristics of the optical imaging system 100 according to the present embodiment, and Table 2 shows aspherical surface values ​​of the optical imaging system 100 according to the present embodiment. Figure 2 and Figure 3 ∠ is an aberration curve of the optical imaging system 100 according to this embodiment.

[0106] Table 1

[0107] Surface number Radius of curvature Thickness / distance Glass Code Y semi-aperture X semi-aperture part S1 7.6294 1.2150 743972.4485 3.2609 3.2609 First lens S2 -117.7929 0.3000 3.3131 3.3131 S3 -10.2950 0.3200 637777.3464 3.3097 3.3097 Second lens S4 6.8799 0.5688 3.2562 3.2562 S5 117.5235 1.0962 743972.4485 3.2644 3.2644 The third lens S6 -11.0483 0.5000 3.2294 3.2294 S7 infinity 3.1500 721743.2950 3.0000 4.0000 Prism S8 infinity 3.1500 721743.2950 4.2426 4.0000 S9 infinity 22.6055 3.0000 4.0000 S10 infinity 0.2100 518274.6417 3.0000 4.0000 Optical Filters S11 infinity 1.0000 2.9977 2.9977 S12 infinity -0.0066 3.0094 3.0094 Imaging surface

[0108] Table 2

[0109] Surface number S1 S2 S3 S4 S5 S6 K 0.0000E+00 0.0000E+00 0.0000E+00 2.1678E+00 0.0000E+00 0.0000E+00 A -7.4221E-04 8.2934E-04 4.0013E-03 -2.7423E-03 -2.7352E-03 -4.2059E-04 B -8.9399E-06 2.4474E-05 -3.1930E-04 1.8195E-05 2.8005E-04 7.0287E-05 C 4.4126E-06 4.2472E-06 2.4431E-05 -1.1984E-05 -4.2723E-06 5.6261E-06 D -8.2480E-07 -8.5384E-07 -7.6642E-07 8.1628E-07 8.2474E-07 3.7637E-07

[0110] Will refer to Figure 4 An optical imaging system 200 according to the second embodiment is described.

[0111] The optical imaging system 200 may include a lens group LG and an optical path converter FE. The configuration of the optical imaging system 200 is not limited to the lens group LG and the optical path converter FE. For example, the optical imaging system 200 may also include a filter IF disposed between the optical path converter FE and the imaging plane IP.

[0112] The lens group LG may include a plurality of lenses. For example, the lens group LG may include a first lens 210, a second lens 220, and a third lens 230 arranged sequentially from the object side. The configuration of the lens group LG is not limited to the first lens 210 to the third lens 230. For example, the lens group LG may consist of only the first lens 210 and the second lens 220. As another example, the lens group LG may be configured to include the first lens 210 to the fourth lens (not shown).

[0113] The first lens 210 may have positive refractive power. The first lens 210 may have a convex object-side surface and a convex image-side surface. The second lens 220 may have negative refractive power. The second lens 220 may have a concave object-side surface and a concave image-side surface. The third lens 230 may have positive refractive power. The third lens 230 may have a convex object-side surface and a convex image-side surface.

[0114] The optical path converter FE may include a plurality of prisms P1, P2, P3 and P4. For example, the optical path converter FE may include a first prism P1, a second prism P2, a third prism P3 and a fourth prism P4. The first prism P1 to the fourth prism P4 may be disposed between the lens group LG and the imaging plane IP.

[0115] The first prism P1 to the fourth prism P4 can be configured to convert the optical path of the lens group LG. In more detail, the first prism P1 to the fourth prism P4 can convert the optical path of the incident light in different directions. For example, the first prism P1 can reflect the light incident along the first optical axis C1 in the direction of the second optical axis C2, the second prism P2 can reflect the light incident along the second optical axis C2 in the direction of the third optical axis C3, the third prism P3 can reflect the light incident along the third optical axis C3 in the direction of the fourth optical axis C4, and the fourth prism P4 can reflect the light incident along the fourth optical axis C4 in the direction of the fifth optical axis C5 (i.e., in the direction of the imaging plane IP).

[0116] The first to fourth prisms P1 to P4 may be configured to reflect incident light in a direction intersecting with the incident light direction. For example, the second optical axis C2 may be formed in a direction intersecting with the first optical axis C1, the third optical axis C3 may be formed in a direction intersecting with the second optical axis C2, and the fourth optical axis C4 may be formed in a direction intersecting with the third optical axis C3, and the fifth optical axis C5 may be formed in a direction intersecting with the fourth optical axis C4.

[0117] Table 3 shows lens characteristics of the optical imaging system 200 according to the present embodiment, and Table 4 shows aspherical surface values ​​of the optical imaging system 200 according to the present embodiment. Figure 5 ∠ is an aberration curve of the optical imaging system 200 according to this embodiment.

[0118] Table 3

[0119]

[0120]

[0121] Table 4

[0122] Surface number S1 S2 S3 S4 S5 S6 K 0.0000E+00 0.0000E+00 0.0000E+00 2.1678E+00 0.0000E+00 0.0000E+00 A -7.4221E-04 8.2934E-04 4.0013E-03 -2.7423E-03 -2.7352E-03 -4.2059E-04 B -8.9399E-06 2.4474E-05 -3.1930E-04 1.8195E-05 2.8005E-04 7.0287E-05 C 4.4126E-06 4.2472E-06 2.4431E-05 -1.1984E-05 -4.2723E-06 5.6261E-06 D -8.2480E-07 -8.5384E-07 -7.6642E-07 8.1628E-07 8.2474E-07 3.7637E-07

[0123] Reference Figure 6 An optical imaging system 300 according to the third embodiment is described.

[0124] The optical imaging system 300 may include a lens group LG and an optical path converter FE. The configuration of the optical imaging system 300 is not limited to the lens group LG and the optical path converter FE. For example, the optical imaging system 300 may further include a filter IF disposed between the optical path converter FE and the imaging plane IP.

[0125] 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 arranged sequentially from the object side. The configuration of the lens group LG is not limited to the first lens 310 to the third lens 330. For example, the lens group LG may consist of only the first lens 310 and the second lens 320. As another example, the lens group LG may be configured to include the first lens 310 to the fourth lens (not shown).

[0126] The first lens 310 may have positive refractive power. The first lens 310 may have a convex object-side surface and a convex image-side surface. The second lens 320 may have negative refractive power. The second lens 320 may have a concave object-side surface and a concave image-side surface. The third lens 330 may have positive refractive power. The third lens 330 may have a convex object-side surface and a convex image-side surface.

[0127] The optical path converter FE may include a plurality of prisms P1 and P2. For example, the optical path converter FE may include a first prism P1 and a second prism P2. The first prism P1 and the second prism P2 may be disposed between the lens group LG and the imaging plane IP.

[0128] The first prism P1 and the second prism P2 may be configured to convert the optical path of the lens group LG. In more detail, the first prism P1 and the second prism P2 may convert the optical path of the incident light in a direction intersecting the first optical axis C1 or in a direction parallel to the first optical axis C1. For example, the first prism P1 may reflect the light incident along the first optical axis C1 in the direction of the second optical axis C2, and the second prism P2 may reflect the light incident along the second optical axis C2 in the direction of the third optical axis C3 (i.e., in the direction of the imaging plane IP).

[0129] The first prism P1 and the second prism P2 may be configured to reflect the incident light in a direction intersecting the incident light direction. For example, the second optical axis C2 may be formed in a direction intersecting the first optical axis C1, and the third optical axis C3 may be formed in a direction intersecting the second optical axis C2.

[0130] Table 5 shows lens characteristics of the optical imaging system 300 according to the present embodiment, and Table 6 shows aspherical surface values ​​of the optical imaging system 300 according to the present embodiment. Figure 7 ∠ is an aberration curve of the optical imaging system 300 according to this embodiment.

[0131] Table 5

[0132] Surface number Radius of curvature Thickness / distance Glass Code Y semi-aperture X semi-aperture part S1 7.6294 1.2150 743972.4485 3.2609 3.2609 First lens S2 -117.7929 0.3000 3.2504 3.2504 S3 -10.2950 0.3200 637777.3464 3.2478 3.2478 Second lens S4 6.8799 0.5688 3.2039 3.2039 S5 117.5235 1.0962 743972.4485 3.2118 3.2118 The third lens S6 -11.0483 0.5000 3.1857 3.1857 S7 infinity 3.1500 721743.2950 3.0000 4.0000 First Prism S8 infinity 3.1500 721743.2950 4.2426 4.0000 S9 infinity 18.8207 3.0000 4.0000 S10 infinity 3.0000 721743.2950 2.8000 3.8000 Second prism S11 infinity 3.0000 721743.2950 3.9598 3.8000 S12 infinity 0.3000 2.8000 3.8000 S13 infinity 0.2100 518274.6417 3.0000 4.0000 Optical Filters S14 infinity 1.0000 2.9920 2.9920 S15 infinity -0.0066 3.0047 3.0047 Imaging surface

[0133] Table 6

[0134] Surface number S1 S2 S3 S4 S5 S6 K 0.0000E+00 0.0000E+00 0.0000E+00 2.1678E+00 0.0000E+00 0.0000E+00 A -7.4221E-04 8.2934E-04 4.0013E-03 -2.7423E-03 -2.7352E-03 -4.2059E-04 B -8.9399E-06 2.4474E-05 -3.1930E-04 1.8195E-05 2.8005E-04 7.0287E-05 C 4.4126E-06 4.2472E-06 2.4431E-05 -1.1984E-05 -4.2723E-06 5.6261E-06 D -8.2480E-07 -8.5384E-07 -7.6642E-07 8.1628E-07 8.2474E-07 3.7637E-07

[0135] Reference Figure 8 An optical imaging system 400 according to a fourth embodiment is described.

[0136] The optical imaging system 400 may include a lens group LG and an optical path converter FE. The configuration of the optical imaging system 400 is not limited to the lens group LG and the optical path converter FE. For example, the optical imaging system 400 may further include a filter IF disposed between the optical path converter FE and the imaging plane IP.

[0137] The lens group LG may include a plurality of lenses. For example, the lens group LG may include a first lens 410, a second lens 420, and a third lens 430 arranged sequentially from the object side. The configuration of the lens group LG is not limited to the first lens 410 to the third lens 430. For example, the lens group LG may also include a lens disposed in the optical path converter FE (refer to Figure 8 , a lens between the first prism P1 and the second prism P2).

[0138] The first lens 410 may have positive refractive power. The first lens 410 may have a convex object-side surface and a convex image-side surface. The second lens 420 may have negative refractive power. The second lens 420 may have a concave object-side surface and a concave image-side surface. The third lens 430 may have positive refractive power. The third lens 430 may have a convex object-side surface and a convex image-side surface.

[0139] The optical path converter FE may include a plurality of prisms P1, P2, and P3. For example, the optical path converter FE may include a first prism P1, a second prism P2, and a third prism P3. The first prism P1 to the third prism P3 may be disposed between the lens group LG and the imaging plane IP.

[0140] The first prism P1 to the third prism P3 may be configured to convert the optical path of the lens group LG. In more detail, the first prism P1 to the third prism P3 may convert the optical path of the incident light in a direction intersecting the first optical axis C1 or in a direction parallel to the first optical axis C1. For example, the first prism P1 may reflect the light incident along the first optical axis C1 in the direction of the second optical axis C2, the second prism P2 may reflect the light incident along the second optical axis C2 in the direction of the third optical axis C3, and the third prism P3 may reflect the light incident along the third optical axis C3 in the direction of the fourth optical axis C4 (i.e., in the direction of the imaging plane IP).

[0141] The first to third prisms P1 to P3 may be configured to reflect the incident light in a direction intersecting the incident light. For example, the second optical axis C2 may be formed in a direction intersecting the first optical axis C1, the third optical axis C3 may be formed in a direction intersecting the second optical axis C2, and the fourth optical axis C4 may be formed in a direction intersecting the third optical axis C3.

[0142] Table 7 shows lens characteristics of the optical imaging system 400 according to the present embodiment, and Table 8 shows aspherical surface values ​​of the optical imaging system 400 according to the present embodiment. Fig. 9 ∫ is an aberration curve of the optical imaging system 400 according to this embodiment.

[0143] Table 7

[0144]

[0145]

[0146] Table 8

[0147] Surface number S1 S2 S3 S4 S5 S6 K 0.0000E+00 0.0000E+00 0.0000E+00 2.1678E+00 0.0000E+00 0.0000E+00 A -7.4221E-04 8.2934E-04 4.0013E-03 -2.7423E-03 -2.7352E-03 -4.2059E-04 B -8.9399E-06 2.4474E-05 -3.1930E-04 1.8195E-05 2.8005E-04 7.0287E-05 C 4.4126E-06 4.2472E-06 2.4431E-05 -1.1984E-05 -4.2723E-06 5.6261E-06 D -8.2480E-07 -8.5384E-07 -7.6642E-07 8.1628E-07 8.2474E-07 3.7637E-07

[0148] Will refer to Fig.10 An optical imaging system 500 according to a fifth embodiment is described.

[0149] The optical imaging system 500 may include a lens group LG and an optical path converter FE. The configuration of the optical imaging system 500 is not limited to the lens group LG and the optical path converter FE. For example, the optical imaging system 500 may further include an optical filter IF disposed between the optical path converter FE and the imaging plane IP.

[0150] The lens group LG may include a plurality of lenses. For example, the lens group LG may include a first lens 510, a second lens 520, and a third lens 530 arranged sequentially from the object side. The configuration of the lens group LG is not limited to the first lens 510 to the third lens 530. For example, the lens group LG may also include a lens disposed in the optical path converter FE (refer to Fig.10 , a lens between the first prism P1 and the second prism P2).

[0151] The first lens 510 may have positive refractive power. The first lens 510 may have a convex object-side surface and a convex image-side surface. The second lens 520 may have negative refractive power. The second lens 520 may have a concave object-side surface and a concave image-side surface. The third lens 530 may have positive refractive power. The third lens 530 may have a convex object-side surface and a convex image-side surface.

[0152] The optical path converter FE may include a plurality of prisms P1 and P2 and a plurality of Pecan prisms PE1 and PE2. For example, the optical path converter FE may include a first prism P1, a second prism P2, a first Pecan prism PE1, and a second Pecan prism PE2. The first prism P1, the second prism P2, the first Pecan prism PE1, and the second Pecan prism PE2 may be disposed between the lens group LG and the imaging plane IP.

[0153] The first prism P1, the second prism P2, the first Pecan prism PE1, and the second Pecan prism PE2 may be configured to convert the optical path of the optical imaging system 500. When commanded, the first prism P1 and the second prism P2 may convert the optical path of incident light in a direction intersecting the first optical axis C1 or in a direction parallel to the first optical axis C1, and the first Pecan prism PE1 and the second Pecan prism PE2 may be configured to reflect light emitted from the first prism P1 two or more times in a plane direction intersecting the first optical axis C1, respectively.

[0154] The following will refer to Fig.11 describe Fig.10 The light path in the Pechan prism shown in .

[0155] The first Pecan prism PE1 and the second Pecan prism PE2 may be configured to form a long light path in a limited space. For example, the first Pecan prism PE1 and the second Pecan prism PE2 may be configured to reflect incident light twice or more. As another example, the second Pecan prism PE2 may include a surface capable of reflecting light while allowing light to be incident or emitted. As a specific example, the first surface PE2S1 of the second Pecan prism PE2 may allow light to be incident and may reflect light, and the second surface PE2S2 of the second Pecan prism PE2 may reflect light and may emit light.

[0156] The first Pecan prism PE1 and the second Pecan prism PE2 configured as described above may reflect light emitted from the first prism P1 five or more times. For example, the first surface PE1S1 of the first Pecan prism PE1 may reflect light incident along the second optical axis C2 in the direction of the third optical axis C3, and the second surface PE1S2 of the first Pecan prism PE1 may reflect light incident along the third optical axis C3 in the direction of the fourth optical axis C4. As another example, the second surface PE2S2 of the second Pecan prism PE2 may reflect light incident along the fourth optical axis C4 in the direction of the fifth optical axis C5, the third surface PE2S3 of the second Pecan prism PE2 may reflect light incident along the fifth optical axis C5 in the direction of the sixth optical axis C6, and the first surface PE2S1 of the second Pecan prism PE2 may reflect light incident along the direction of the sixth optical axis C6 in the direction of the seventh optical axis C7.

[0157] Therefore, according to the present embodiment, even in a limited space, an optical path having a considerable length can be formed by the first Pecan prism PE1 and the second Pecan prism PE2 to implement the optical imaging system 500 having a long focal length.

[0158] Table 9 shows lens characteristics of the optical imaging system 500 according to the present embodiment, and Table 10 shows aspherical surface values ​​of the optical imaging system 500 according to the present embodiment. Fig.12∠ is an aberration curve of the optical imaging system 500 according to this embodiment.

[0159] Table 9

[0160] Surface number Radius of curvature Thickness / distance Glass Code Y semi-aperture X semi-aperture part S1 7.6294 1.2150 743972.4485 2.7273 2.7273 First lens S2 -117.7929 0.3000 2.6684 2.6684 S3 -10.2950 0.3200 637777.3464 2.6610 2.6610 Second lens S4 6.8799 0.5688 2.6321 2.6321 S5 117.5235 1.0962 743972.4485 2.6507 2.6507 The third lens S6 -11.0483 0.5000 2.6979 2.6979 S7 infinity 3.0000 721743.2950 3.0000 3.0000 First Prism S8 infinity 3.0000 721743.2950 4.2426 3.0000 S9 infinity 1.0000 3.0000 3.0000 S10 infinity 3.2000 721743.2950 3.2000 3.2000 The first Pechan prism S11 infinity 4.5255 721743.2950 3.2000 4.5255 S12 infinity 3.2000 721743.2950 3.2000 3.4637 S13 infinity 0.1000 3.2000 3.2000 S14 infinity 3.2000 721743.2950 3.2000 3.2000 Second Pechan Prism S15 infinity 6.4000 721743.2950 3.2000 4.5255 S16 infinity 4.5255 721743.2950 3.2000 3.4637 S17 infinity 4.5255 721743.2950 3.2000 4.5255 S18 infinity 1.0000 3.2000 3.2000 S19 infinity 3.0000 721743.2950 3.0000 3.0000 Second prism S20 infinity 3.0000 721743.2950 4.2426 3.0000 S21 infinity 0.3000 3.0000 3.0000 S22 infinity 0.2100 518274.6417 2.9000 3.2000 Optical Filters S23 infinity 0.7167 2.9885 2.9885 S24 infinity 0.0066 3.0078 3.0078 Imaging surface

[0161] Table 10

[0162] Surface number S1 S2 S3 S4 S5 S6 K 0.0000E+00 0.0000E+00 0.0000E+00 2.1678E+00 0.0000E+00 0.0000E+00 A -7.4221E-04 8.2934E-04 4.0013E-03 -2.7423E-03 -2.7352E-03 -4.2059E-04 B -8.9399E-06 2.4474E-05 -3.1930E-04 1.8195E-05 2.8005E-04 7.0287E-05 C 4.4126E-06 4.2472E-06 2.4431E-05 -1.1984E-05 -4.2723E-06 5.6261E-06 D -8.2480E-07 -8.5384E-07 -7.6642E-07 8.1628E-07 8.2474E-07 3.7637E-07

[0163] Tables 11 to 13 show optical characteristic values ​​and conditional expression values ​​of the optical imaging systems according to the first to fifth embodiments.

[0164] Table 11

[0165]

[0166]

[0167] Table 12

[0168] First embodiment Second embodiment Third embodiment Fourth embodiment Fifth embodiment TOH 10.50 11.60 11.60 10.30 11.10 TOL 30.60 21.80 31.80 29.40 22.00 TOW 8.80 16.10 8.80 13.80 11.70 PEH N / A N / A N / A N / A 6.40 PEL N / A N / A N / A N / A 7.80 PEW N / A N / A N / A N / A 12.80 DPE12 N / A N / A N / A N / A 0.10 DPEP N / A N / A N / A N / A 0.50 DLRP1 0.50 0.50 0.50 0.50 0.50 P1W 8.00 8.00 8.00 8.00 6.00 P1H 6.00 6.00 6.00 6.00 6.00 DPA N / A 0.10 N / A 0.10 N / A

[0169] Table 13

[0170]

[0171] The optical imaging systems 100, 200, 300, 400, and 500 according to the present specification may be installed in a portable electronic device. For example, one or more of the optical imaging systems according to the first to fifth embodiments may be installed in a portable electronic device such as a Fig.13 On the rear surface or front surface of the portable terminal 10 shown in , where the rear surface or the front surface may be parallel to a plane defined by the X-axis direction and the Z-axis direction and intersect with the thickness direction (Y-axis direction) of the portable terminal 10 .

[0172] According to the present disclosure, an optical imaging system that can be mounted on a portable electronic device while enlarging an image sensor can be provided.

[0173] Furthermore, according to the present disclosure, the degree of freedom in arrangement of image sensors can be increased to reduce the external size of the optical imaging system.

[0174] Although specific exemplary embodiments have been shown and described above, it will be apparent after understanding the present disclosure that various changes in form and detail may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described in this application are considered to be illustrative only and not for limiting purposes. The description of the features or aspects in each example is considered to be applicable to similar features or aspects in other examples. If the described techniques are performed in a different order, and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways, and / or replaced or supplemented by other components or their equivalents, appropriate results may be obtained. Therefore, the scope of the present disclosure is not limited by specific embodiments, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents will be interpreted as included in the present disclosure.

Claims

1. An optical imaging system, comprising: A lens group including at least one lens forming a first optical axis; And An optical path converter disposed between the lens group and the imaging surface, Wherein the lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side, Wherein the first lens has a positive refractive power, the second lens has a negative refractive power, and the third lens has a positive refractive power, and Satisfies the following conditional expressions: -0.28 < f2 / f < -0.18 and 1.0 < BFL / f < 1.6, Where f is the focal length of the optical imaging system, f2 is the focal length of the second lens, and BFL is the distance of the optical path from the image side surface of the third lens to the imaging surface.

2. The optical imaging system according to claim 1, wherein: The first lens has a convex object side surface.

3. The optical imaging system according to claim 1, wherein: The second lens has a concave object side surface.

4. The optical imaging system according to claim 1, wherein: The third lens has a convex object side surface.

5. An optical imaging system, comprising: A lens group including at least one lens forming a first optical axis; And An optical path converter disposed between the lens group and the imaging surface, Wherein the lens group includes a first lens, a second lens, and a third lens arranged in sequence from the object side, Wherein the first lens has a positive refractive power, the second lens has a negative refractive power, and the third lens has a positive refractive power, and Satisfies the following conditional expressions: 0.40 < f3 / f < 0.50, Where f is the focal length of the optical imaging system, and f3 is the focal length of the third lens.

6. The optical imaging system according to claim 5, wherein: The first lens has a convex object side surface.

7. The optical imaging system according to claim 5, wherein: The second lens has a concave object side surface.

8. The optical imaging system according to claim 5, wherein: The third lens has a convex object side surface.

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