Optical-mechanical system and electronic device comprising optical-mechanical system

Abstract

An opto-mechanical system and an electronic device comprising the opto-mechanical system, characterized in that the opto-mechanical system (1) comprises a first lens device (2) defining a first optical axis (A1); an image sensor (3) intersecting a second optical axis (A2), the second optical axis (A2) extending parallel to the first optical axis (A1); a reflective element (4) for redirecting light between the first lens arrangement (2) and the image sensor (3), the first lens arrangement (2) and the image sensor (3) being arranged on a first side of the reflective element (4); the first actuator (5) is used for enabling the first lens device (2) to generate at least partial displacement along the first optical axis (A1) or enabling the reflecting element (4) to generate displacement along a displacement axis (A3) parallel to the first optical axis (A1). The first actuator (5) may facilitate autofocus and / or optical stabilization within the opto-mechanical system (1).

Description

Technical Field

[0001] This disclosure relates to an optomechanical system for an electronic device, the optomechanical system including a lens assembly, an image sensor, a reflective element, and an actuator. Background Technology

[0002] Optical systems for portable electronic devices face several challenges. Portable electronic devices such as smartphones preferably have the smallest possible external size, while optical systems typically require a certain minimum size to provide sufficiently good image sharpness, spatial frequency response, and sensitivity.

[0003] One of the challenges is how to provide imaging systems with ultra-long focal lengths (e.g., equivalent to film focal lengths in the range of conventional 90mm to 280mm lens systems).

[0004] To provide long focal lengths, narrow field-of-view lenses are typically required. However, a narrow field of view can lead to less than ideal optical properties. First, the lens's modulation transfer function (MTF) value, a measure of sharpness and spatial frequency, is limited by diffraction due to the narrow aperture. The lower the MTF value, the blurrier the image and the fewer high-frequency details are visible. Second, the optical system becomes less sensitive in low light, leading to longer exposure times and consequently, poorer image quality. Long exposure times make it difficult to capture moving subjects effectively, and any hand tremor during long exposures will degrade image quality.

[0005] These problems can be avoided or mitigated by providing imaging systems with larger entrance pupil diameters for such narrow fields of view, thereby reducing diffraction and improving sensitivity in low light. Larger entrance pupil diameters improve the performance of the optical system; however, they also result in a shorter focal length.

[0006] To achieve long focal lengths with sufficient image quality, existing solutions suggest folding the light path. One such solution is a Cassegrain-based double-reflection system. A Cassegrain embodiment includes a parabolic primary mirror and a hyperbolic secondary mirror, the latter reflecting light through an aperture in the primary mirror. By folding the light path, the optical system can be designed to be more compact.

[0007] However, the secondary mirror obscures the central portion of the system's entrance pupil aperture, leaving only an annular entrance pupil aperture. This annular entrance pupil aperture exhibits significantly reduced performance compared to designs that include a fully open entrance pupil aperture. Larger secondary mirrors result in lower MTF values ​​at lower spatial frequencies.

[0008] Therefore, there is a need for improved optical engines for portable and / or smaller electronic devices. Utility Model Content

[0009] The object of this disclosure is to provide an improved optomechanical system. The above and other objects are achieved through the features of the independent claims. Other implementations will be apparent from the dependent claims, the specification, and the drawings.

[0010] According to a first aspect, an optomechanical system for an electronic device is provided, the optomechanical system comprising: a first lens assembly defining a first optical axis; an image sensor intersecting a second optical axis extending parallel to the first optical axis; a reflective element for redirecting light between the first lens assembly and the image sensor, the first lens assembly and the image sensor being disposed on a first side of the reflective element; and a first actuator for displacing the first lens assembly at least partially along the first optical axis or displacing the reflective element along a displacement axis parallel to the first optical axis.

[0011] Such a system reflects incident light, resulting in a focal length longer than the actual external dimensions of the optomechanical system and the reflecting element. When used in optomechanical systems (such as cameras), reflecting elements that provide a longer focal length produce higher magnification and a narrower field of view. Furthermore, components capable of achieving longer focal lengths have small packages and occupy as little space as possible within the electronics that include them.

[0012] In one possible implementation of the first aspect, the reflective element is used to reflect light, which enters the interior of the reflective element through the first lens device, is reflected sequentially by several reflective surfaces inside the reflective element, and exits from the reflective element in a direction toward the image sensor, thereby achieving a long focal length and thin package.

[0013] In another possible implementation of the first aspect, the first actuator is coplanar with at least one of the first lens device, the reflective element, and the image sensor in a first plane to ensure the thinnest possible package.

[0014] In another possible implementation of the first aspect, the first actuator is disposed on a second side of the reflective element, the second side being opposite to the first side of the reflective element, and the first actuator is used to move the reflective element along the displacement axis, thereby reducing the size of the actuator stroke required for macro focusing.

[0015] In another possible implementation of the first aspect, the optomechanical system further includes a printed circuit board configured adjacent to the second side of the reflective element, the printed circuit board including the first actuator such that the actuator can be embedded in the printed circuit board.

[0016] In another possible implementation of the first aspect, the first actuator includes a voice coil motor, a stepper motor, a piezoelectric motor, or a shape memory alloy, making it possible to use any suitable type of simple, small, and reliable actuator with low power consumption.

[0017] In another possible implementation of the first aspect, the optomechanical system further includes a tunable lens disposed between the first lens assembly and the reflective element, wherein the first actuator is coplanar with the reflective element and is used to actuate the tunable lens at least partially along the first optical axis, the tunable lens being used to engage the first lens assembly such that actuation of the tunable lens causes at least one lens within the first lens assembly to move along the first optical axis, thereby facilitating the integration of autofocus into the optomechanical system.

[0018] In another possible implementation of the first aspect, the optomechanical system further includes a second lens device that defines the second optical axis and is disposed between the reflective element and the image sensor, which helps to achieve a further improved imaging system.

[0019] In another possible implementation of the first aspect, the optomechanical system further includes a second actuator positioned adjacent to at least one of the first lens assembly and the image sensor, the second actuator being used to move the first lens assembly and / or the image sensor in a direction perpendicular to the first optical axis and the second optical axis. This allows for the implementation of optical image stabilization independently while still maintaining the thinnest possible package.

[0020] In another possible implementation of the first aspect, the second actuator is used to move the first lens assembly and the second lens assembly in a direction perpendicular to the first optical axis and the second optical axis, thereby enabling autofocus and optical image stabilization while still maintaining the thinnest possible package.

[0021] In another possible implementation of the first aspect, the second actuator is used to move the first lens device and the image sensor simultaneously in a direction perpendicular to the first optical axis and the second optical axis, thereby enabling optical image stabilization while still maintaining the thinnest possible package.

[0022] In another possible implementation of the first aspect, the second actuator is used to move at least one of the first lens device, the second lens device, and the image sensor in a direction parallel to the first optical axis and the second optical axis, thereby enabling focusing to be achieved using the second actuator.

[0023] In another possible implementation of the first aspect, the second actuator is used to move the first lens assembly in a direction perpendicular to the first and second optical axes, and the optomechanical system further includes a third actuator for moving the image sensor in a direction perpendicular to the first and second optical axes. This makes it possible to achieve autofocus and optical image stabilization separately while still maintaining the thinnest possible package.

[0024] In another possible implementation of the first aspect, the first actuator, the second actuator, and / or the third actuator comprise a voice coil motor or a shape memory alloy, enabling the use of any suitable type of simple, small, and reliable actuator with low power consumption.

[0025] According to a second aspect, an electronic device is provided that includes the optomechanical system described above. Such a system reflects incident light such that the focal length is longer than the actual external dimensions of the optomechanical system and the reflecting element. When used in an optomechanical system (such as a camera), the reflecting element providing the longer focal length produces higher magnification and a narrower field of view. The electronic device incorporating such an optomechanical system can have a thin package while still possessing a long focal length.

[0026] In one possible implementation of the second aspect, the optomechanical system is configured such that the first and second optical axes of the optomechanical system extend perpendicularly to the main surface of the electronic device, thereby enabling the optomechanical system to be as compact and precise as possible, allowing the electronic device to generate high-quality images while remaining relatively small.

[0027] These and other aspects will become apparent from the embodiments described below. Attached Figure Description

[0028] In the following detailed description of the invention, various aspects, embodiments, and implementations are explained in more detail with reference to exemplary embodiments shown in the accompanying drawings, in which:

[0029] Figure 1 A schematic diagram of an example optomechanical system according to an embodiment of the present disclosure is shown;

[0030] Figure 2 A schematic diagram of an example optomechanical system according to an embodiment of the present disclosure is shown;

[0031] Figure 3 A schematic diagram of an example optomechanical system according to an embodiment of the present disclosure is shown. Detailed Implementation

[0032] The present invention relates to an optomechanical system 1 for an electronic device 11, the optomechanical system 1 comprising: a first lens device 2 defining a first optical axis A1; an image sensor 3 intersecting a second optical axis A2 extending parallel to the first optical axis A1; a reflective element 4 for redirecting light between the first lens device 2 and the image sensor 3, the first lens device 2 and the image sensor 3 being disposed on a first side of the reflective element 4; and a first actuator 5 for displacing the first lens device 2 at least partially along the first optical axis A1 or displacing the reflective element 4 along a displacement axis A3 parallel to the first optical axis A1.

[0033] The present invention also relates to an electronic device 11 comprising the optomechanical system 1 detailed below. The electronic device 11 may be a smartphone, tablet computer, wearable device, or any type of electronic device having an optical system.

[0034] The optomechanical system 1 can be configured such that a first optical axis A1 and an optional second optical axis A2 extend perpendicularly to the main surface of the electronic device, wherein the first optical axis A1 is defined by the first lens device 2 and the second optical axis A2 is defined by the second lens device 9. For example, the main surface of the electronic device can be formed by the wall of a housing, the housing wall including a light path entrance aperture coaxially arranged with the first lens device 2. The entrance aperture can be circular and have an unobstructed inner diameter, allowing all light entering the aperture to pass unimpeded through the first lens device 2 and reach the reflecting element 4.

[0035] As described above, the optomechanical system 1 includes a first lens device 2, defining a first optical axis A1, such as... Figures 1 to 3 As shown.

[0036] The image sensor 3 is configured to intersect with the second optical axis A2, which extends parallel to the first optical axis A1.

[0037] The optomechanical system 1 may also include a second lens device 9, which defines a second optical axis A2 and is disposed between the reflective element 4 and the image sensor 3.

[0038] The second lens device 9 can be configured such that its optical axis is coaxial with the optical axis A2 of the image sensor 3. The first lens device 2 and the second lens device 9 can be configured such that the optical axis of the second lens device 9 is parallel to the optical axis A1 of the first lens device 2.

[0039] The first lens assembly 2 and the second lens assembly 9 may each include at least one lens. A diffractive optical element may be included at the front of the first lens assembly 2 to reduce the total number of lenses while still maintaining sufficient color correction. Furthermore, the first lens assembly 2 may include a prism, such as a freeform prism, to improve and simplify the first lens assembly 2.

[0040] The lens of the second lens assembly 9 can have any suitable cutout, such as an I-shaped cutout or a D-shaped cutout, which frees up space within the second lens assembly 9.

[0041] The reflective element 4 is used to redirect light between the first lens assembly 2 and the image sensor 3, which are disposed on a first side of the reflective element 4. The first side of the reflective element 4 may be the side facing outward when disposed within an electronic device.

[0042] The reflective element 4 can be used to reflect light internally. Light enters the interior of the reflective element 4 through the first lens assembly 2, and thereafter is sequentially reflected by several reflective surfaces within the reflective element 4, and finally exits from the reflective element 4 in a direction toward the image sensor 3. The reflective element 4 includes at least three reflective surfaces, which may include mirrors. At least one surface of the reflective element 4 can be used to reflect light by total internal reflection.

[0043] The first lens device 2 can be configured as a first region adjacent to the main surface of the reflective element 4, and the image sensor 3 can be configured as a second region adjacent to the main surface of the reflective element 4. The optical axes of the first lens device 2 and the image sensor 3 can extend perpendicularly to the main surface of the reflective element 4.

[0044] The optomechanical system 1 can be used to allow light rays to pass through the first lens assembly 2 and enter the interior of the reflective element 4. Thereafter, the light rays are internally reflected by several reflective surfaces, and finally, the light rays exit from the reflective element 4 and reach the image sensor 3.

[0045] The first actuator 5 is used to cause the first lens assembly 2 to undergo at least partial displacement along the first optical axis A1, such as Figure 1 and Figure 3 As shown, or the reflecting element 4 can be displaced along a displacement axis A3 parallel to the first optical axis A1, such as... Figure 2 As shown.

[0046] The first actuator 5 can be coplanarly disposed within the first plane P1 with at least one of the first lens assembly 2, the reflective element 4, and the image sensor 3. For example... Figure 1 and Figure 3 As shown, the first actuator 5 can be arranged coplanarly with the reflective element 4. The first actuator 5 can be located on one side of the reflective element 4, or it can be configured as other components surrounding the reflective element 4 and the optional optomechanical system 1.

[0047] like Figure 2 As shown, the first actuator 5 can be disposed on the second side of the reflective element 4, which is opposite to the first side of the reflective element 4. In other words, the second side of the reflective element 4 can be the side facing the interior of the electronic device 11.

[0048] The first actuator 5 can be used to move the reflecting element 4 along the displacement axis A3. In such an embodiment, the first lens assembly 2 can be fixed.

[0049] The optomechanical system 1 may include a printed circuit board 6 positioned adjacent to a second side of the reflective element 4. The printed circuit board 6 may include a first actuator 5, such that the first actuator 5 is part of the printed circuit board 6.

[0050] The first actuator 5 may include a voice coil motor, a stepper motor, a piezoelectric motor, or a shape memory alloy.

[0051] like Figure 1 and Figure 3 As shown, the optomechanical system 1 may also include a tunable lens 7 disposed between the first lens assembly 2 and the reflecting element 4.

[0052] The first actuator 5 may be coplanar with the reflecting element 4 and is used to actuate the tunable lens 7 at least partially along the first optical axis A1. In other words, the tunable lens 7 is used to engage the first lens assembly 2 such that actuation of the tunable lens 7 causes at least one lens within the first lens assembly 2 to move along the first optical axis A1. The tunable lens 7 may comprise an optical liquid or a soft optical material, and it can move the first lens assembly 2 or its lenses by actuation.

[0053] The tunable lens 7 can be used to integrate autofocus functionality. However, autofocus can also be performed, for example, by moving the reflective element 4 along the displacement axis A3.

[0054] The optomechanical system 1 may further include a second actuator 8, configured adjacent to at least one of the first lens assembly 2 and the image sensor 3. The second actuator 8 is used to move the first lens assembly 2, such as... Figure 2 and Figure 3 As shown, and / or move the image sensor 3 in a direction perpendicular to the first optical axis A1 and the second optical axis A2, such as Figure 1 As shown.

[0055] For example, optical image stabilization (OIS) can be performed by moving the first lens device 2 and the optional second lens device 9 in the xy plane (where the optical axis A1 is the z-axis); or by moving the image sensor 3 in the xy plane.

[0056] The second actuator 8 can be used to move the first lens assembly 2 and the second lens assembly 9 in a direction perpendicular to the first optical axis A1 and the second optical axis A2, such as... Figure 2 As shown.

[0057] The second actuator 8 can be used to move the first lens device 2 and the image sensor 3 simultaneously in a direction perpendicular to the first optical axis A1 and the second optical axis A2. In other words, the second actuator 8 can be used to move the first lens device 2 and the image sensor 3.

[0058] The second actuator 8 can also be used to move at least one of the first lens device 2, the second lens device 9, and the image sensor 3 in a direction parallel to the first optical axis A1 and the second optical axis A2, so that the second actuator 8 can achieve focusing.

[0059] The second actuator 8 can be used to move only the first lens assembly 2 in a direction perpendicular to the first optical axis A1 and the second optical axis A2. In such an embodiment, the optomechanical system 1 may include, for example, Figure 3 The third actuator 10 is shown. The third actuator 10 can be used to generate a so-called sensor offset, that is, to move the image sensor 3 in a direction perpendicular to the first optical axis A1 and the second optical axis A2. In other words, the second actuator 8 can be used to move the first lens device 2, while the third actuator 10 is used to move the image sensor 3.

[0060] The first actuator 5, the second actuator 8, and / or the third actuator 10 may include a voice coil motor or a shape memory alloy.

[0061] This document has described various aspects and implementations in conjunction with various embodiments. However, those skilled in the art, upon studying the accompanying drawings, the invention, and the appended claims, will be able to understand and implement other variations of the disclosed embodiments in practicing the claimed subject matter. In the claims, the word "comprising" does not exclude other elements or steps, and "a" or "an" does not exclude a plurality. The enumeration of measures in mutually different dependent claims does not imply that a combination of these measures cannot be used to obtain an advantage.

[0062] The reference numerals used in the claims should not be construed as limiting the scope. Unless otherwise stated, the drawings (e.g., cross shading, component arrangements, scale, degrees, etc.) should be read in conjunction with the specification and should be considered an integral part of the entire written description of the invention. The terms “horizontal,” “vertical,” “left,” “right,” “up,” and “down,” as well as their adjective and adverbial derivatives (e.g., “horizontally,” “to the right,” “upward,” etc.) used herein, when a particular drawing is facing the reader, simply indicate the orientation of the illustrated structure. Similarly, the terms “inward” and “outward” generally refer to the orientation of a surface relative to its axis of elongation or axis of rotation (where applicable).

Claims

1. An optomechanical system (1), characterized in that, The optical-mechanical system (1) includes The first lens device (2) defines the first optical axis (A1); The image sensor (3) intersects with the second optical axis (A2), which extends parallel to the first optical axis (A1); A reflective element (4) is used to redirect light between the first lens device (2) and the image sensor (3), the first lens device (2) and the image sensor (3) being disposed on a first side of the reflective element (4); The first actuator (5) is used to cause the first lens device (2) to be displaced at least partially along the first optical axis (A1) or to cause the reflective element (4) to be displaced along a displacement axis (A3) parallel to the first optical axis (A1).

2. The optomechanical system (1) according to claim 1, characterized in that, The reflective element (4) is used to reflect light, which enters the interior of the reflective element (4) through the first lens device (2), and is reflected sequentially by several reflective surfaces inside the reflective element (4), and is emitted from the reflective element (4) in a direction toward the image sensor (3).

3. The optomechanical system (1) according to claim 1 or 2, characterized in that, The first actuator (5) is coplanar with at least one of the first lens device (2), the reflective element (4) and the image sensor (3) in a first plane (P1).

4. The optomechanical system (1) according to claim 1 or 2, characterized in that, The first actuator (5) is disposed on the second side of the reflective element (4), wherein the second side is opposite to the first side of the reflective element (4), and the first actuator (5) is used to move the reflective element (4) along the displacement axis (A3).

5. The optomechanical system (1) according to claim 4, characterized in that, It also includes a printed circuit board (6) configured adjacent to the second side of the reflective element (4), the printed circuit board (6) including the first actuator (5).

6. The optomechanical system (1) according to claim 4, characterized in that, The first actuator (5) includes a voice coil motor, a stepper motor, a piezoelectric motor, or a shape memory alloy.

7. The optomechanical system (1) according to claim 4, characterized in that, Also includes: A tunable lens (7) is disposed between the first lens assembly (2) and the reflective element (4). A first actuator (5) is coplanar with the reflective element (4) and is used to actuate the tunable lens (7) at least partially along the first optical axis (A1). The tunable lens (7) is used to engage the first lens assembly (2) such that actuation of the tunable lens (7) causes at least one lens in the first lens assembly (2) to move along the first optical axis (A1).

8. The optomechanical system (1) according to claim 1, characterized in that, It also includes a second lens device (9) that defines the second optical axis (A2) and is disposed between the reflective element (4) and the image sensor (3).

9. The optomechanical system (1) according to claim 1, characterized in that, It also includes a second actuator (8), wherein the second actuator (8) is configured to be adjacent to at least one of the first lens device (2) and the image sensor (3), and the second actuator (8) is used to move the first lens device (2) and / or the image sensor (3) in a direction perpendicular to the first optical axis (A1) and the second optical axis (A2).

10. The optomechanical system (1) according to claim 8, characterized in that, The second actuator (8) is used to move the first lens device (2) and the second lens device (9) in a direction perpendicular to the first optical axis (A1) and the second optical axis (A2).

11. The optomechanical system (1) according to claim 9, characterized in that, The second actuator (8) is used to move the first lens device (2) and the image sensor (3) simultaneously in a direction perpendicular to the first optical axis (A1) and the second optical axis (A2).

12. The optomechanical system (1) according to claim 9, characterized in that, The second actuator (8) is used to move at least one of the first lens device (2), the second lens device (9) and the image sensor (3) in a direction parallel to the first optical axis (A1) and the second optical axis (A2).

13. The optomechanical system (1) according to claim 9, characterized in that, The second actuator (8) is used to move the first lens device (2) in a direction perpendicular to the first optical axis (A1) and the second optical axis (A2). The optomechanical system (1) further includes a third actuator (10) for moving the image sensor (3) in a direction perpendicular to the first optical axis (A1) and the second optical axis (A2).

14. The optomechanical system (1) according to claim 1, characterized in that, The first actuator (5), the second actuator (8) and / or the third actuator (10) include a voice coil motor or a shape memory alloy.

15. An electronic device (11) comprising an optomechanical system, characterized in that, Includes the optomechanical system (1) according to any one of claims 1 to 14.

16. The electronic device (11) according to claim 15, characterized in that, The optomechanical system (1) is configured such that the first optical axis (A1) and the second optical axis (A2) of the optomechanical system (1) extend perpendicularly to the main surface of the electronic device (11).

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