Optical system and electronic device

Abstract

Provided is an optical system capable of simultaneously achieving miniaturization of a camera using a large-size image sensor and an autofocus function for achieving a macro function, and an electronic device having the optical system. The optical system includes a first reflecting member provided on an object side and a second reflecting member provided on an imaging surface side. Each of the first reflecting member and the second reflecting member has a lens shape having a refractive power on an entrance surface and an exit surface. In one embodiment, the optical system includes a first lens group including the first reflecting member and having a positive refractive power, a second lens group having the positive refractive power, and a third lens group including the second reflecting member and having a negative refractive power.

Description

Technical Field

[0001] The present invention relates to an optical system comprising multiple lenses and lens groups, and an electronic device having the optical system. Background Technology

[0002] In recent years, small electronic devices such as digital cameras and mobile phones have become increasingly popular, and these devices typically incorporate compact camera modules. There is a strong demand for miniaturization of these camera modules, especially along the thickness of the electronic device.

[0003] On the other hand, the image quality of camera systems installed in electronic devices is constantly improving. Furthermore, to enhance image quality, more and more electronic devices are using large-size image sensors and large-aperture lenses. In addition, macro photography using telephoto lenses is becoming increasingly common, emerging as a new added function for electronic devices. Therefore, a lens system that simultaneously fulfills macro photography requirements is needed.

[0004] However, these requirements for camera modules and lens systems are contradictory and difficult to meet simultaneously by simply extending traditional lens technology. This is especially true for telephoto lens systems, due to their longer focal lengths; therefore, achieving miniaturization while maintaining brightness, large aperture, and macro photography capabilities is a significant challenge.

[0005] For example, the lens system described in U.S. Patent No. 11,194,133 can be considered a technique for reducing the size of lens systems. In this lens system, an optical path bending prism is arranged on the object side, and a focusing group consisting of a lens element with refractive power and an image sensor is arranged on the image side. Focusing is then performed by moving the focusing group. According to this lens system, the height of the camera module can be limited to the height of the image sensor. Therefore, increasing the number of lenses and increasing the size of the focusing group does not affect the height of the camera module. Such a lens system consists of two focusing lens groups that move during focusing. However, the focusing lens groups cannot have sufficient power to achieve the optical magnification required for macro photography. Similarly, from the perspective of image sensor layout, the size of the image sensor is proportional to the height of the camera module. That is, the height of the image sensor directly determines the size of the camera, which is detrimental to increasing the size of the image sensor. Therefore, it is difficult for this lens system to balance the improvement in image quality from a large image sensor with the miniaturization of the lens system.

[0006] Furthermore, as a configuration for achieving macro photography, a macro lens described in U.S. Patent No. 10,215,999 is known. The macro lens comprises a first focusing lens group with negative refractive power and a second focusing lens group with positive refractive power. These two focusing lens groups then move with different amounts of movement. Because this configuration complicates the arrangement of the focusing lens groups, miniaturization is difficult. Alternatively, a macro lens described in U.S. Patent No. 7,009,779 is known with another configuration. In this macro lens, when focusing from infinity to near distance, the front lens group moves forward to the object plane; this architecture necessitates a longer lens system. This configuration makes size reduction difficult because the total length of the lens changes during focusing and becomes longer. Summary of the Invention

[0007] The present invention addresses the aforementioned problems and aims to simultaneously achieve miniaturization of cameras employing large-size image sensors and autofocus functionality for macro photography.

[0008] According to a first aspect of the present invention, an optical system is provided, comprising a first reflective member disposed on the object side and a second reflective member disposed on the imaging surface side. Each of the first reflective member and the second reflective member has a lens shape that has refractive power on the incident surface and the exit surface.

[0009] According to the aforementioned aspect, in an optical system including a first reflective member and a second reflective member, each of the first reflective member and the second reflective member has a lens shape having refractive power on the incident and exit surfaces. Therefore, since the height of the optical system is independent of the height of the image sensor, it is possible to simultaneously achieve camera miniaturization and autofocus functionality for macro photography.

[0010] According to one possible implementation of the first aspect, the optical system includes: The first lens assembly includes the first reflective member and has positive refractive power; The second lens assembly has the aforementioned positive refractive power; The third lens assembly includes the second reflective member and has negative refractive power.

[0011] According to the implementation method, since the focusing lens group can have sufficient power, the autofocus function that enables macro photography can be achieved.

[0012] According to one possible implementation of the first aspect, the second lens group is configured to be movable along the optical axis.

[0013] According to the implementation method, focusing can be achieved from infinity to close distance by extending the second lens group toward the object side.

[0014] According to one possible implementation of the first aspect, at least one surface of at least one of the first reflective member and the second reflective member has an aspherical lens shape.

[0015] According to the implementation method, at least one surface can be shaped like an aspherical lens to achieve an optical system with less image distortion.

[0016] According to one possible implementation of the first aspect, when the exit surface of the second reflective member has the aspherical lens shape, the aspherical lens shape includes an inflection point.

[0017] According to the implementation method, spherical aberration can be removed using an aspherical lens shape that includes the inflection point.

[0018] According to one possible implementation of the first aspect, the incident surface of the first reflective member has positive refractive power, and the exit surface of the first reflective member has negative refractive power.

[0019] According to the implementation method, since the incident surface of the first reflective member has positive refractive power and the exit surface has negative refractive power, the chromatic aberration of the first lens group can be corrected.

[0020] According to one possible implementation of the first aspect, the incident and exit surfaces of the second reflective member have negative refractive power.

[0021] According to the implementation method, since the incident and exit surfaces of the second reflective member have negative refractive power, chromatic aberration can be corrected within the third lens group.

[0022] According to one possible implementation of the first aspect, the exit surface of the second reflective member has an aspherical lens shape.

[0023] According to the aforementioned implementation, since the exit surface of the second reflective member has an aspherical lens shape, an optical system with less distortion can be realized.

[0024] According to one possible implementation of the first aspect, the focal length EFLP1 of the first reflecting member and the focal length EFLP2 of the second reflecting member satisfy the following conditions: 1.3<| EFLP1 / EFLP2 |<3.1(1).

[0025] According to the implementation method, the optimal range of refractive power of the first lens group and the second reflective member having a lens shape can be set relative to the optical system.

[0026] According to one possible implementation of the first aspect, the length TP1 on the optical axis of the first reflecting member and the length TP2 on the optical axis of the second reflecting member satisfy the following condition: 1.0 < | TP1 / TP2 | < 1.8 (2).

[0027] According to the implementation method, the size of the first lens group and the size of the second reflective member having the lens shape can be set within a suitable range.

[0028] According to one possible implementation of the first aspect, the focal length EFLP1 of the first reflective member and the focal length EFLGp2 of the second lens group satisfy the following conditions: 0.8<| EFLP1 / EFLGp2 |<3.7(3).

[0029] According to the implementation method, the optimal range of refractive power for the first lens group and the second lens group can be set.

[0030] According to one possible implementation of the first aspect, the focal length EFLP2 of the second reflective member and the focal length EFLGp2 of the second lens group satisfy the following conditions: 0.2<| EFLP2 / EFLGp2 |<1.6 (4).

[0031] According to the implementation method, the optimal range of refractive power of the second reflective member having the lens shape and the refractive power of the second lens group can be set.

[0032] According to one possible implementation of the first aspect, the focal length EFLP1 of the first reflective element and the focal length EFL of the entire optical system satisfy the following conditions: 1.0<| EFLP1 / EFL |<1.7(5).

[0033] According to the implementation method, the optimal refractive power of the first lens group in the optical system can be set.

[0034] According to one possible implementation of the first aspect, the focal length EFLP2 of the second reflective element and the focal length EFL of the entire optical system satisfy the following conditions: 0.5<| EFLP2 / EFL |<1.1(6).

[0035] According to the implementation method, the refractive power of the second reflective member with the optimal lens shape in the optical system can be set.

[0036] According to one possible implementation of the first aspect, the focal length EFLP1 of the first reflective member and the focal length EFLGp3 of the third lens group satisfy the following conditions: 2.8<| EFLP1 / EFLGp3 |<5.6 (7).

[0037] According to the implementation method, the optimal refractive power of the best lens of the first lens group and the third lens group can be set.

[0038] According to a second aspect of the present invention, an electronic device is provided, comprising the optical system described above. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments, the accompanying drawings required for describing the embodiments of the present invention are briefly introduced below. Obviously, the drawings described below only depict some possible embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1A The configuration of the optical system for infinity photography according to an embodiment is shown; Figure 1B The configuration of the optical system for macro photography according to an embodiment is shown; Figure 2A The configuration of the optical system for infinity photography according to the first example is shown; Figure 2B The configuration of the optical system for macro photography according to the first example is shown; Figure 2C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the first example; Figure 3A The configuration of the optical system for infinity photography according to the second example is shown; Figure 3B The configuration of the optical system for macro photography according to the second example is shown; Figure 3C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the second example; Figure 4A The configuration of the optical system for infinity photography according to the third example is shown; Figure 4B The configuration of the optical system for macro photography according to the third example is shown; Figure 4C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the third example; Figure 5AThe configuration of the optical system for infinity photography according to the fourth example is shown; Figure 5B The configuration of the optical system for macro photography according to the fourth example is shown; Figure 5C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the fourth example; Figure 6A The configuration of the optical system for infinity photography according to the fifth example is shown; Figure 6B The configuration of the optical system for macro photography according to the fifth example is shown; Figure 6C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the fifth example; Figure 7A The configuration of the optical system for infinity photography according to the sixth example is shown; Figure 7B The configuration of the optical system for macro photography according to the sixth example is shown; Figure 7C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to the sixth example; Figure 8 The configuration of an electronic device according to an embodiment is shown. Detailed Implementation

[0040] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0041] Figure 1A A diagram illustrating the configuration of an optical system for infinity photography according to an embodiment of the present invention is shown. This diagram is a cross-sectional view of the image sensor along its short side; all subsequent views are cross-sectional views along the short side. The optical system 100 includes a first lens group Gp1, a second lens group Gp2, and a third lens group Gp3. Figure 1A In the image, lenses L11 and L12, L21 to L23, and L31 to L33 are lens elements with refractive power.

[0042] The first lens group Gp1 is disposed on the object side and includes a first prism unit PU1 as a first reflecting member. The first prism unit PU1 includes a first lens L11 with positive refractive power, a right-angle prism PR1, and a second lens L12 with negative refractive power. Lens L11 is in contact with the incident surface of the right-angle prism PR1, and lens L12 is in contact with the exit surface of the right-angle prism PR1. The right-angle prism PR1 bends the optical axis AX1 of the incident light toward the optical axis AX2.

[0043] The second lens group Gp2 includes a first lens L21 with positive refractive power, a second lens L22 with negative refractive power, and a third lens L23 with positive refractive power.

[0044] The third lens group Gp3 is located on the imaging plane side and includes a first lens L31 with negative refractive power and a second prism unit PU2 as a second reflector. The second prism unit PU2 includes a second lens L32 with negative refractive power, a right-angle prism PR2 as a second reflector, and a third lens L33 with negative refractive power. Lens L32 is in contact with the incident surface of the right-angle prism PR2, and lens L33 is in contact with the exit surface of the right-angle prism PR2. The right-angle prism PR2 bends the optical axis AX2 of the incident light towards the optical axis AX3. A sensor unit S is located on the exit surface side of lens L33. For example, the sensor unit S located on the imaging plane side can be a CMOS type image sensor.

[0045] Typically, the image sensor is arranged perpendicular to the optical axis along the longitudinal direction of the camera module (e.g., axis AX2 in the example of FIG1). In this case, the height direction of the camera module coincides with the height direction of the image sensor. Therefore, the thickness of the electronic device is proportional to the height of the image sensor. Conversely, in the embodiments of the present invention, the height of the camera module is independent of the height of the sensor portion S, because the sensor portion S is arranged perpendicular to the height direction of the camera module. Therefore, according to the embodiments of the present invention, a camera module employing a large-size image sensor can be miniaturized.

[0046] In the above configuration, the first lens group Gp1 has a positive refractive index, the second lens group Gp2 has a positive refractive index, and the third lens group Gp3 has a negative refractive index.

[0047] Furthermore, at least one of the incident and exit surfaces of the first prism unit PU1 and the incident and exit surfaces of the second prism unit PU2 may have an aspherical lens shape.

[0048] In embodiments of this application, the lens L33 has an aspherical lens shape on the surface of the imaging plane, and the aspherical lens shape may have an inflection point.

[0049] Figure 1BA diagram illustrating the configuration of an optical system for macro photography according to an embodiment of the present invention is shown. A second lens group Gp2, having positive refractive power, can be movably configured in the direction of the optical axis AX2 used for focusing. Figure 1B As shown, the second lens group Gp2 extends to the object side when focusing from infinity to close distance. According to an embodiment of the present invention, while maintaining the miniaturization of the camera module in the height direction, the moving distance of the second lens group Gp2 can be increased. Therefore, it is possible to simultaneously achieve miniaturization of the camera module and autofocus functionality for macro photography.

[0050] Next, the conditions for the focal length of the lens group in the optical system according to an embodiment of the present invention will be described.

[0051] Preferably, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLP2 of the second prism unit PU2 satisfy the following conditions: 1.3<| EFLP1 / EFLP2 |<3.1(1).

[0052] Preferably, such as Figure 1B As shown, when the length of the optical axis of the first prism unit PU1 is TP1 and the length of the optical axis of the second prism unit PU2 is TP2, the following condition is satisfied: 1.0 < | TP1 / TP2 | < 1.8 (2).

[0053] Preferably, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.8<| EFLP1 / EFLGp2 |<3.7(3).

[0054] Preferably, the focal length EFLP2 of the second prism unit PU2 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.2<| EFLP2 / EFLGp2 |<1.6 (4).

[0055] Preferably, the focal length EFLP1 of the first prism unit PU1 and the focal length EFL of the entire optical system 100 satisfy the following conditions: 1.0<| EFLP1 / EFL |<1.7(5).

[0056] Preferably, the focal length EFLP2 of the second prism unit PU2 and the focal length EFL of the entire optical system 100 satisfy the following conditions: 0.5<| EFLP2 / EFL |<1.1(6).

[0057] Preferably, the focal length EFLP1 of the first reflecting member and the focal length EFLGp3 of the third lens group satisfy the following conditions: 2.8<| EFLP1 / EFLGp3 |<5.6 (7).

[0058] (Example 1) Figure 2A A diagram illustrating the configuration of an optical system for infinity photography according to a first example of the present invention is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power.

[0059] Figure 2B A diagram illustrating the configuration of an optical system for macro photography according to an embodiment of the present invention is shown. A second lens group Gp2, having positive refractive power, can be movably configured in the direction of the optical axis AX2 used for focusing. Figure 2B As shown, the second lens group Gp2 moves to the object side when focusing from infinity to close distance.

[0060] Table 1-1 shows the lens data for this example, specifically the radius of curvature R and lens thickness or spacing D for each optical surface, as well as the refractive index nd and Abbe number vd at a wavelength of 587.56 nm (d line).

[0061] Table 1-1

[0062] Tables 1-2 to 1-4 show the aspherical coefficients of each optical surface of the aspherical lens according to the optical system of this example. The aspherical profile is represented by the following formula:

[0063] Table 1-2

[0064] Table 1-3

[0065] Table 1-4

[0066] Figure 2C Simulation results for spherical aberration, field curvature, and distortion aberrations of the F-line (486 nm), d-line (587 nm), and C-line (656 nm wavelength) in the optical system according to this example are shown. Figure 2C In this context, Sag represents the imaging position in the sagittal beam, and Tan represents the imaging position in the meridional beam.

[0067] In this example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.8<| EFLP1 / EFLGp2 |<3.7(3).

[0068] Under these conditions, the optimal range of refractive power for the first lens group Gp1 and the second lens group Gp2 can be set. If this condition is not met, the refractive power of the second lens group Gp2 becomes too strong, resulting in large aberrations. Alternatively, the refractive power of the second lens group Gp2 becomes weaker than needed and cannot maintain sufficient focusing function.

[0069] In the same example, the focal length EFLP2 of the second prism unit PU2 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.2<| EFLP2 / EFLGp2 |<1.6 (4).

[0070] Under these conditions, the optimal range of refractive power for the second prism unit PU2, which has a lens shape, and the refractive power for the second lens group Gp2 can be set. If this condition is not met, the refractive power of the second prism unit PU2 may be too high or too low. This leads to problems such as the lens portion on the second prism unit PU2 becoming too thick to be miniaturized, or the lens portion becoming too thin to be difficult to manufacture.

[0071] from Figure 2C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0072] (Example 2) Figure 3A A diagram illustrating the configuration of the optical system for infinity photography according to a second example of the present invention is shown. Figure 3B A diagram illustrating the configuration of the optical system for macro photography according to this example is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power.

[0073] Table 2-1 shows the lens data for the optical system according to this example. In this example, the radius of curvature R of the lens group is different from that in the first example, as shown below.

[0074] Table 2-1

[0075] Tables 2-2 to 2-4 show the aspherical coefficients of each optical surface of the aspherical lens of the optical system according to this example.

[0076] Table 2-2

[0077] Table 2-3

[0078] Table 2-4

[0079] Figure 3C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to this example.

[0080] In this example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLP2 of the second prism unit PU2 satisfy the following conditions: 1.3<| EFLP1 / EFLP2 |<3.1(1).

[0081] Under these conditions, the optimal range of refractive power for the first lens group Gp1 and the second prism unit PU2, which has a lens shape, can be determined. If this condition is not met, the optical system will become too large, which is detrimental to reducing the size of the optical system.

[0082] In the same example, the focal length EFLP2 of the second prism unit PU2 and the focal length EFL of the entire optical system satisfy the following conditions: 0.5<| EFLP2 / EFL |<1.1(6).

[0083] Under these conditions, the refractive power of the second prism unit PU2 with the optimal lens shape in the optical system can be set. If this condition is not met, the required flange back distance for production cannot be guaranteed.

[0084] Furthermore, in this example, the focal length ELP1 of the first prism unit PU1 and the focal length EFLGp3 of the third lens group Gp3 satisfy the following conditions: 2.8<| EFLP1 / EFLGp3 |<5.6 (7).

[0085] Under these conditions, the refractive power of the first lens group Gp1 and the third lens group Gp3 can be optimally set. If this condition is not met, the refractive power arrangement of the three lens groups will be tilted towards the first lens group Gp1 or the third lens group Gp3. Therefore, it will be difficult to achieve a balance between miniaturization of the optical system, increasing the magnification of macro photography, and optimizing aberration correction.

[0086] from Figure 3C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0087] (Example 3) Figure 4A A diagram illustrating the configuration of the optical system for infinity photography according to a third example of the present invention is shown. Figure 4B A diagram illustrating the configuration of the optical system for macro photography according to this example is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power.

[0088] Table 3-1 shows the lens data for the optical system according to this example. In this example, the radius of curvature R and lens thickness or spacing D are different from those in the first example, as shown below.

[0089] Table 3-1

[0090] Tables 3-2 to 3-4 show the aspherical coefficients of each optical surface of the aspherical lens in the optical system according to this example.

[0091] Table 3-2

[0092] Table 3-3

[0093] Table 3-4

[0094] Figure 4C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to this example.

[0095] In this example, the length TP1 on the optical axis of the first prism unit PU1 and the length TP2 on the optical axis of the second prism unit PU2 satisfy the following condition: 1.0 < | TP1 / TP2 | < 1.8 (2).

[0096] Under these conditions, the dimensions of the first lens group Gp1 and the second prism unit PU2, which has a lens shape, can be set within a suitable range. If this condition is not met, the balance between the lens aperture and the image plane size will be disrupted, making it difficult to achieve aberration correction while maintaining lens light intensity.

[0097] from Figure 4C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0098] (Example 4) Figure 5AA diagram illustrating the configuration of the optical system for infinity photography according to a fourth example of the present invention is shown. Figure 5B A diagram illustrating the configuration of the optical system for macro photography according to this example is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power.

[0099] Table 4-1 shows the lens data for the optical system according to this example. In this example, the radius of curvature R, lens thickness or spacing D, and the refractive index nd and Abbe number vd of the d-line are different from those in the first example, as shown below.

[0100] Table 4-1

[0101] Tables 4-2 to 4-4 show the aspherical coefficients of each optical surface of the aspherical lens in the optical system according to this example.

[0102] Table 4-2

[0103] Table 4-3

[0104] Table 4-4

[0105] Figure 5C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to this example.

[0106] In this example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFL of the entire optical system satisfy the following conditions: 1.0<| EFLP1 / EFL |<1.7(5).

[0107] Under these conditions, the optimal refractive power of the first lens group Gp1 in the optical system can be set. If this condition is not met, significant aberrations will occur in the first lens group Gp1, including the first prism unit PU1, making it difficult to maintain good optical performance.

[0108] In the same example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLGp3 of the third lens group Gp3 satisfy the following conditions: 2.8<| EFLP1 / EFLGp3 |<5.6 (7).

[0109] from Figure 5C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0110] (Example 5) Figure 6A A diagram illustrating the configuration of the optical system for infinity photography according to a fifth example of the present invention is shown. Figure 6B A diagram illustrating the configuration of the optical system for macro photography according to this example is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power. In this example, the radius of curvature R and lens thickness or spacing D are different from those in the first example, as shown below. The right-angle prism PR2 is also arranged such that light traveling along the optical axis AX2 bends 90° towards the top of the diagram and travels along the optical axis AX3 in the opposite direction to the incident light. The sensor unit S is disposed above the third lens group Gp3. With this optical system configuration, the height of the electronic device no longer depends on the height of the sensor unit S as in the optical system shown in FIG1. ​​Therefore, according to embodiments of the present invention, the size of the electronic device can be reduced.

[0111] Table 5-1 shows the lens data for the optical system according to this example.

[0112] Table 5-1

[0113] Tables 5-2 to 5-4 show the aspherical coefficients of each optical surface of the aspherical lens of the optical system according to this example.

[0114] Table 5-2

[0115] Table 5-3

[0116] Table 5-4

[0117] Figure 6C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to this example.

[0118] In this example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLP2 of the second prism unit PU2 satisfy the following conditions: 1.3<| EFLP1 / EFLP2 |<3.1(1).

[0119] In addition, the length TP1 on the optical axis of the first prism unit PU1 and the length TP2 on the optical axis of the second prism unit PU2 satisfy the following conditions: 1.0 < | TP1 / TP2 | < 1.8 (2).

[0120] Furthermore, the focal length EFLP2 of the second prism unit PU2 and the focal length EFL of the entire optical system satisfy the following conditions: 0.5<| EFLP2 / EFL |<1.1(6).

[0121] from Figure 6C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0122] (Example 6) Figure 7A A diagram illustrating the configuration of the optical system for infinity photography according to a sixth example of the present invention is shown. Figure 7B A diagram illustrating the configuration of the optical system for macro photography according to this example is shown. The optical system, from the object side, includes: a first lens group Gp1 with positive refractive power, a second lens group Gp2 with positive refractive power, and a third lens group Gp3 with negative refractive power.

[0123] Table 6-1 shows the lens data for the optical system according to this example. This example is another example where the radius of curvature R and lens thickness or spacing D are different from the first example, as shown below.

[0124] Table 6-1

[0125] Tables 6-2 to 6-4 show the aspherical coefficients of each optical surface of the aspherical lens of the optical system according to this example.

[0126] Table 6-2

[0127] Table 6-3

[0128] Table 6-4

[0129] Figure 7C The spherical aberration, field curvature, and distortion for each wavelength are shown in the optical system according to this example.

[0130] In this example, the focal length EFLP1 of the first prism unit PU1 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.8<| EFLP1 / EFLGp2 |<3.7(3).

[0131] In addition, the focal length EFLP2 of the second prism unit PU2 and the focal length EFLGp2 of the second lens group Gp2 satisfy the following conditions: 0.2<| EFLP2 / EFLGp2 |<1.6 (4).

[0132] Furthermore, the focal length EFLP1 of the first prism unit PU1 and the focal length EFL of the entire optical system satisfy the following conditions: 1.0<| EFLP1 / EFL |<1.7(5).

[0133] from Figure 7C As can be seen, in the optical system based on this example, each aberration is well corrected.

[0134] Table 7 shows the relationship between the micro-magnification of the optical systems in Examples 1 to 6 and the parameters included in Equations (1) to (6).

[0135] Table 7

[0136] In Table 7, underlines indicate the maximum and minimum values ​​for each parameter. These values ​​are shown in the two columns on the right side of the table.

[0137] Figure 8 The configuration of an electronic device 800 according to an embodiment of the present invention is shown. The electronic device 800 has a camera 802 implementing the optical system described above and a graphics processing unit (GPU) 804. The camera 802 is used to convert an image into digital image data through the optical system of the present invention and input the digital image data to the GPU 804. The GPU 804 is used to process the digital image data received from the camera 802.

[0138] exist Figure 8 Although the electronic device 800 includes three cameras 802, the number of cameras can be one, two, four, or more. In the electronic device 800, at least one camera can implement the optical system of the present invention.

[0139] The above description is merely a specific implementation of the present invention and is not intended to limit the scope of protection of the present invention. Any variations or substitutions that are readily conceived by those skilled in the art within the scope of the disclosed technology should fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An optical system, characterized in that, It includes a first reflecting member disposed on the object side and a second reflecting member disposed on the imaging surface side. Each of the first reflective member and the second reflective member has a lens shape that has refractive power on the incident surface and the exit surface.

2. The optical system according to claim 1, characterized in that, Also includes: The first lens assembly includes the first reflective member and has positive refractive power; The second lens assembly has the aforementioned positive refractive power; The third lens assembly includes the second reflective member and has negative refractive power.

3. The optical system according to claim 2, characterized in that, The second lens group is configured to be movable along the optical axis.

4. The optical system according to claim 1, characterized in that, At least one surface of at least one of the first reflective member and the second reflective member has an aspherical lens shape.

5. The optical system according to claim 4, characterized in that, When the exit surface of the second reflective member has the aspherical lens shape, the aspherical lens shape includes an inflection point.

6. The optical system according to claim 1, characterized in that, The incident surface of the first reflective member has positive refractive power, and the exit surface of the first reflective member has negative refractive power.

7. The optical system according to claim 1, characterized in that, The incident and exit surfaces of the second reflective member have negative refractive power.

8. The optical system according to claim 7, characterized in that, The exit surface of the second reflective member has an aspherical lens shape.

9. The optical system according to claim 1, characterized in that, The focal lengths EFLP1 of the first reflecting member and EFLP2 of the second reflecting member satisfy the following conditions: 1.3<| EFLP1 / EFLP2 |<3.1(1).

10. The optical system according to claim 1, characterized in that, The lengths TP1 on the optical axis of the first reflective member and TP2 on the optical axis of the second reflective member satisfy the following condition: 1.0 < | TP1 / TP2 | < 1.8 (2).

11. The optical system according to claim 2, characterized in that, The focal length EFLP1 of the first reflective element and the focal length EFLGp2 of the second lens group satisfy the following conditions: 0.8<| EFLP1 / EFLGp2 |<3.7(3).

12. The optical system according to claim 2, characterized in that, The focal length EFLP2 of the second reflective element and the focal length EFLGp2 of the second lens group satisfy the following conditions: 0.2<| EFLP2 / EFLGp2 |<1.6 (4).

13. The optical system according to claim 1, characterized in that, The focal length EFLP1 of the first reflective element and the focal length EFL of the entire optical system satisfy the following conditions: 1.0<| EFLP1 / EFL |<1.7(5).

14. The optical system according to claim 1, characterized in that, The focal length EFLP2 of the second reflective element and the focal length EFL of the entire optical system satisfy the following conditions: 0.5<| EFLP2 / EFL |<1.1(6).

15. The optical system according to claim 2, characterized in that, The focal length EFLP1 of the first reflective element and the focal length EFLGp3 of the third lens group satisfy the following conditions: 2.8<| EFLP1 / EFLGp3 |<5.6 (7).

16. An electronic device, characterized in that, Includes the optical system according to any one of claims 1 to 15.

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