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CN-115867833-B - Controllable lens actuated via flexible joint

CN115867833BCN 115867833 BCN115867833 BCN 115867833BCN-115867833-B

Abstract

The present invention relates to a controllable lens having variable optical power. The lens comprises first and second cover members (111, 112), a transparent, deformable non-fluid body (105) interposed between the first and second transparent cover members such that the first and second transparent cover members and the non-fluid body constitute a lens, one or more actuators arranged to provide displacement in a direction along the optical axis, and one or more elastic elements (130, 130_1, 130_2) connecting the actuator displacement elements with the first cover member, wherein at least a portion of each of the one or more elastic elements is arranged to elastically deform in response to a relative radial displacement between the first transparent cover member and the actuator displacement elements.

Inventors

  • Pierre Crane
  • Jenny Tapani capinene
  • Vladimir kartaschev

Assignees

  • 珀莱特股份有限公司

Dates

Publication Date
20260505
Application Date
20210622
Priority Date
20200622

Claims (15)

  1. 1. A controllable lens (100) having a variable optical power, the lens comprising: a first cover member (111) and a second cover member (112), wherein one of the first cover member and the second cover member is transparent and the other of the first cover member and the second cover member is transparent or reflective, A transparent, deformable non-fluid body (105) interposed between the first and second cover members such that the first and second cover members and the non-fluid body constitute a lens having an optical axis (150) intersecting the first and second cover members and the non-fluid body, One or more actuators (121) comprising a plurality of actuator displacement elements (122) arranged to be displaced in a direction parallel to the optical axis and arranged to cause bending of at least a first cover member in response to a force provided by the one or more actuators, One or more elastic elements (130, 130_1, 130_2) connecting the actuator displacement element with the first cover member, wherein at least a portion of each of the one or more elastic elements is arranged to elastically deform in response to a relative radial displacement between the first cover member and the actuator displacement element (122) which is generated in response to a displacement of the actuator displacement element, Wherein each of the one or more elastic elements has a first stiffness in a radial direction and a second stiffness in a direction of the optical axis, wherein the first stiffness is smaller than the second stiffness and the first stiffness is configured to enable radial deformation in a range from 0.05 μm to 500 μm, and wherein the controllable lens is configured such that, in response to displacement of the actuator displacement element (122) in a direction parallel to the optical axis and resulting bending of the first cover member, a surface at an interface between the one or more elastic elements (130) and the first cover member (111) rotates about an axis tangential to a path (151) surrounding the optical axis (150).
  2. 2. A controllable lens according to claim 1, wherein each of the one or more elastic elements is arranged to elastically deform in response to a torque (Ty) about an axis tangential to the path (151) around the optical axis, wherein the torque is generated by a relative radial displacement between the first cover member and the actuator displacement element.
  3. 3. The controllable lens according to claim 1, wherein each of the one or more elastic elements has at least one first portion (201) fixed to the first cover member and a second portion (202) fixed to at least one actuator displacement element, wherein the first and second portions are elastically connected.
  4. 4. A controllable lens according to claim 3, wherein the controllable lens comprises a plurality of first portions (201) of the one or more elastic elements (130), wherein the first portions are connected to the first cover member (101) at discrete locations thereof distributed along a path (151) around the optical axis.
  5. 5. The controllable lens according to claim 1, wherein each of the one or more elastic elements has a first spring constant (k 1) in the radial direction and a second spring constant (k 2) in the direction of the optical axis, wherein the first spring constant (k 1) is smaller than the second spring constant (k 2).
  6. 6. Controllable lens according to claim 1, wherein the actuator is fixed to a fixed support (190) such that the displacement element (122) is arranged to be displaced relative to the fixed support.
  7. 7. The controllable lens according to claim 1, wherein the controllable lens comprises one or more second elastic elements (130 a) connecting the actuator displacement element (122) with the second cover member (112).
  8. 8. The controllable lens of claim 1, wherein each of the one or more elastic elements comprises an elastic adhesive.
  9. 9. The controllable lens according to claim 1, wherein each of the one or more elastic elements (130) comprises one or more spring elements (301), wherein each spring element comprises a first portion (201) according to claim 3.
  10. 10. The controllable lens of claim 9, wherein each of the spring elements is configured as a separate spring element.
  11. 11. Controllable lens according to claim 9, wherein each of the spring elements is configured as a separate spring element and wherein each of the one or more elastic elements comprises a support member (302) arranged as a common support for a plurality of displacement elements (122) and/or a plurality of elastic portions for each of the one or more elastic elements, wherein the support member comprises the second portion (202) according to claim 3.
  12. 12. A controllable lens according to claim 9, wherein each of the spring elements is configured as a separate spring element, and wherein each of the one or more elastic elements comprises a support member (302) arranged as a common support for a plurality of displacement elements (122) and/or a plurality of elastic portions for each of the one or more elastic elements, the support member comprising the second portion (202) according to claim 3, and wherein each of the one or more support members is positioned radially closer to the optical axis than the spring element.
  13. 13. A controllable lens according to claim 1, wherein the controllable lens comprises a first elastic element (130) connecting the actuator displacement element with the first cover member (111) and a second elastic element (130 a) connecting other actuator displacement elements comprised by the controllable lens with the second cover member (112).
  14. 14. A controllable lens according to claim 3, wherein each of the one or more elastic elements comprises one or more spring elements (301) and an elastic material connected to the first and/or second portion (201, 202).
  15. 15. An electronic device comprising a controllable lens (100) according to claim 1.

Description

Controllable lens actuated via flexible joint Technical Field The present invention relates to a lens with a variable focal length, such as a variable lens for use in a miniature camera. Background The use of variable focal length lenses in cameras and other electronic devices is of great interest because such lenses can replace multi-lens systems configured with motors for displacing the lenses to achieve variable focal lengths. Variable focal length lenses may be used to improve the performance of electronic devices and/or to reduce size. There remains a need to improve the performance and quality of variable lenses, such as to reduce the wavefront error performance of the lenses. Disclosure of Invention It is an object of the invention to improve a variable focal length lens. In particular, it is an object of the present invention to provide a suitable actuator mechanism comprising a way of transmitting actuator movements to a lens membrane that does not lead to deformations of the membrane that may lead to aberrations and wavefront errors. In a first aspect of the invention, there is provided a controllable lens having variable optical power, the lens comprising A first cover member and a second cover member, wherein one of the first cover member and the second cover member is transparent and the other of the first cover member and the second cover member is transparent or reflective, A transparent, deformable non-fluid body interposed between the first and second cover members such that the first and second transparent cover members and the non-fluid body constitute a lens having an optical axis intersecting the first and second cover members and the non-fluid body, One or more actuators comprising a plurality of actuator displacement elements arranged to be displaced in a direction parallel or substantially parallel to the optical axis, -One or more elastic elements connecting the actuator displacement element with the first cover member, wherein at least a portion (such as an elastic portion) of each of the one or more elastic elements is arranged to elastically deform in response to a relative radial displacement between the first cover member and the actuator displacement element, wherein each of the one or more elastic elements has a first stiffness in a radial direction and a second stiffness in a direction of the optical axis, wherein the first stiffness is smaller than the second stiffness. The stiffness of the elastic element may be an elastic stiffness, such as the spring rate or the viscoelastic stiffness of a spring. The stiffness may be given by a combination of the dimensions of the elastic element and the properties of the elastic material, such as the young's modulus of the material. The first stiffness and the second stiffness give a relation between the deformation in the radial direction and the axial direction (along the optical axis) and the radial force or radial torque resulting in the radial deformation and the axial force resulting in the axial deformation. Advantageously, the actuator output is connected to the cover member (i.e. the lens membrane) by means of a resilient connecting element, which may accumulate changes in the radial extension of the cover member caused by the actuator, which resilient connecting element may be designed to be resiliently deformed at least in the radial direction in response to bending of the cover member. A relative radial displacement is understood to mean that at least one component of the relative radial displacement has a direction perpendicular to the optical axis in the radial direction. The elastic element comprises a structure having a bendable shape designed to bend in a radial direction (i.e. towards the optical axis) while the structure is less bendable or inflexible or only allows a smaller compression or stretching in an axial direction along the optical axis, wherein the design provides that the first stiffness or radial stiffness is smaller than the second stiffness or axial stiffness. The elastic deformation may include deformation in a radial direction toward the optical axis, deformation in a rotational direction due to torque. Radial deformations may include deformations in the range of 0.05 μm to 500 μm, such as in the range of 0.1 μm to 250 μm, in the range of 0.1 μm to 50 μm, in the range of 0.5 μm to 50 μm, in the range of 1 μm to 25 μm, in the range of 2 μm to 500 μm, in the range of 5 μm to 250 μm, such as in the range of 7 μm to 150 μm. The first cover member is a first transparent cover member and the second cover member is a second transparent cover member or a second reflective cover member. Alternatively, the first cover member is a first transparent cover member or a first reflective cover member, and the second cover member is a second transparent cover member. According to one embodiment, each of the resilient elements is arranged to elastically deform in response to a torque acting about an axis tangential to