US-20260126282-A1 - PRISM MOTOR, METHOD FOR DETECTING A ROTATION ANGLE OF A PRISM MOTOR, AND PHOTOGRAPHING MODULE

US20260126282A1US 20260126282 A1US20260126282 A1US 20260126282A1US-20260126282-A1

Abstract

A prism motor, a method for detecting a rotation angle of a prism motor, and a photographing module are provided. In the prism motor, the first electrode plate is located on a surface of the prism base; the second electrode plate is located on a surface of the prism carrier and disposed opposite to the first electrode plate, and in a case where the prism carrier rotates in one direction about a first rotation axis, either an opposing area between the first electrode plate and the second electrode plate increases while a spacing between the first electrode plate and the second electrode plate decreases, or an opposing area between the first electrode plate and the second electrode plate decreases while a spacing between the first electrode plate and the second electrode plate increases; and the processing unit is configured to determine a rotation angle of the prism carrier.

Inventors

Jun Zou
Yaoguo Zhang
Yulin Zhang

Assignees

CHIPSEMI SEMICONDUCTOR (NINGBO) CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251024
Priority Date: 20241105

Claims (20)

1 . A prism motor, comprising: a prism base; a prism carrier, spaced apart from the prism base, wherein the prism carrier is rotatable relative to the prism base; a first electrode plate, located on a surface of the prism base; a second electrode plate, located on a surface of the prism carrier and disposed opposite to the first electrode plate, wherein the first electrode plate and the second electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a first rotation axis, an opposing area between the first electrode plate and the second electrode plate increases while a spacing between the first electrode plate and the second electrode plate decreases, or an opposing area between the first electrode plate and the second electrode plate decreases while a spacing between the first electrode plate and the second electrode plate increases; and a processing unit, configured to determine a rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate.
2 . The prism motor according to claim 1 , wherein: a number of first electrode plates is even, and the first electrode plates are symmetrically arranged about a first plane where a first rotation axis of the prism carrier is located, the first plane being perpendicular to a plane where the first electrode plates are located; a number of second electrode plates is even, and the second electrode plates are symmetrically arranged about the first plane; the first electrode plates are in one-to-one correspondence with the second electrode plates, and each respective first electrode plate of the first electrode plates and a respective second electrode plate of the second electrode plates forms a capacitor; and the processing unit is configured to determine the rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the respective first electrode plate and the respective second electrode plate.
3 . The prism motor according to claim 2 , wherein each of the first electrode plates is symmetrically arranged about a second plane where a second rotation axis of the prism carrier is located, and each of the second electrode plates is symmetrically arranged about the second plane, the second plane being perpendicular to the plane where the first electrode plates are located, wherein the first rotation axis and the second rotation axis are mutually perpendicular.
4 . The prism motor according to claim 1 , wherein the first electrode plate has a length greater than a length of the second electrode plate, and wherein a length direction of the first electrode plate is parallel to the first rotation axis.
5 . The prism motor according to claim 1 , further comprising: a third electrode plate, located on the surface of the prism base; and a fourth electrode plate, located on the surface of the prism carrier and disposed opposite to the third electrode plate, wherein the third electrode plate and the fourth electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a second rotation axis, either an opposing area between the third electrode plate and the fourth electrode plate increases while a spacing the third electrode plate and the fourth electrode plate decreases, or an opposing area the third electrode plate and the fourth electrode plate decreases while a spacing the third electrode plate and the fourth electrode plate increases, wherein the first rotation axis and the second rotation axis are mutually perpendicular; wherein the processing unit is configured to collectively determine a spatial rotation angle of the prism carrier based on the capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate and a capacitance signal generated by the capacitor formed by the third electrode plate and the fourth electrode plate.
6 . The prism motor according to claim 5 , wherein: a number of third electrode plates is even, and the third electrode plates are symmetrically arranged about a first plane where the second rotation axis of the prism carrier is located, the first plane being perpendicular to a plane where the third electrode plates are located; a number of fourth electrode plates is even, and the fourth electrode plates are symmetrically arranged about the first plane; the third electrode plates are in one-to-one correspondence with the fourth electrode plates, and each respective third electrode plate of the third electrode plates and a respective fourth electrode plate of the fourth electrode plates forms a capacitor.
7 . The prism motor according to claim 2 , further comprising: a third electrode plate, located on the surface of the prism base; and a fourth electrode plate, located on the surface of the prism carrier and disposed opposite to the third electrode plate, wherein the third electrode plate and the fourth electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a second rotation axis, either an opposing area between the third electrode plate and the fourth electrode plate increases while a spacing the third electrode plate and the fourth electrode plate decreases, or an opposing area the third electrode plate and the fourth electrode plate decreases while a spacing the third electrode plate and the fourth electrode plate increases, wherein the first rotation axis and the second rotation axis are mutually perpendicular; wherein the processing unit is configured to collectively determine a spatial rotation angle of the prism carrier based on the capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate and a capacitance signal generated by the capacitor formed by the third electrode plate and the fourth electrode plate.
8 . The prism motor according to claim 7 , wherein: a number of third electrode plates is even, and the third electrode plates are symmetrically arranged about a second plane where the second rotation axis of the prism carrier is located, the second plane being perpendicular to a plane where the third electrode plates are located; a number of fourth electrode plates is even, and the fourth electrode plates are symmetrically arranged about the second plane; the third electrode plates are in one-to-one correspondence with the fourth electrode plates, and each respective third electrode plate of the third electrode plates and a respective fourth electrode plate of the fourth electrode plates forms a capacitor.
9 . The prism motor according to claim 1 , wherein a plane where the first electrode plate is located and a plane where the second electrode plate is located are both parallel to the first rotation axis.
10 . The prism motor according to claim 1 , wherein: a part of an orthographic projection of the first electrode plate toward the second electrode plate falls beyond the second electrode plate, and a part of an orthographic projection of the second electrode plate toward the first electrode plate falls beyond the first electrode plate.
11 . A method for detecting a rotation angle of a prism motor, applied to a prism motor comprising: a prism base; a prism carrier, spaced apart from the prism base, wherein the prism carrier is rotatable relative to the prism base; a first electrode plate, located on a surface of the prism base; a second electrode plate, located on a surface of the prism carrier and disposed opposite to the first electrode plate, wherein the first electrode plate and the second electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a first rotation axis, either an opposing area between the first electrode plate and the second electrode plate increases while a spacing between the first electrode plate and the second electrode plate decreases, or an opposing area between the first electrode plate and the second electrode plate decreases while a spacing between the first electrode plate and the second electrode plate increases; and a processing unit, configured to determine a rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate; the method comprising: determining an initial capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate at an initial position of the prism carrier; determining a current capacitance signal upon a change in capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate; and determining a rotation angle of the prism carrier based on a difference between the current capacitance signal and the initial capacitance signal.
12 . A photographing module, comprising: a prism motor; a lens; and a photosensitive chip, wherein incident light entering the photographing module is reflected by the prism motor, passes through the lens, and reaches the photosensitive chip; wherein the prism motor includes: a prism base; a prism carrier, spaced apart from the prism base, wherein the prism carrier is rotatable relative to the prism base; a first electrode plate, located on a surface of the prism base; a second electrode plate, located on a surface of the prism carrier and disposed opposite to the first electrode plate, wherein the first electrode plate and the second electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a first rotation axis, either an opposing area between the first electrode plate and the second electrode plate increases while a spacing between the first electrode plate and the second electrode plate decreases, or an opposing area between the first electrode plate and the second electrode plate decreases while a spacing between the first electrode plate and the second electrode plate increases; and a processing unit, configured to determine a rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate.
13 . The photographing module according to claim 12 , wherein: a number of first electrode plates is even, and the first electrode plates are symmetrically arranged about a first plane where a first rotation axis of the prism carrier is located, the first plane being perpendicular to a plane where the first electrode plates are located; a number of second electrode plates is even, and the second electrode plates are symmetrically arranged about the first plane; the first electrode plates are in one-to-one correspondence with the second electrode plates, and each respective first electrode plate of the first electrode plates and a respective second electrode plate of the second electrode plates forms a capacitor; and the processing unit is configured to determine the rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the respective first electrode plate and the respective second electrode plate.
14 . The photographing module according to claim 13 , wherein each of the first electrode plates is symmetrically arranged about a second plane where a second rotation axis of the prism carrier is located, and each of the second electrode plates is symmetrically arranged about the second plane the second plane being perpendicular to the plane where the first electrode plates are located, wherein the first rotation axis and the second rotation axis are mutually perpendicular.
15 . The photographing module according to claim 12 , wherein the first electrode plate has a length greater than a length of the second electrode plate, and wherein a length direction of the first electrode plate is parallel to the first rotation axis.
16 . The photographing module according to claim 12 , further comprising: a third electrode plate, located on the surface of the prism base; and a fourth electrode plate, located on the surface of the prism carrier and disposed opposite to the third electrode plate, wherein the third electrode plate and the fourth electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a second rotation axis, either an opposing area between the third electrode plate and the fourth electrode plate increases while a spacing the third electrode plate and the fourth electrode plate decreases, or an opposing area the third electrode plate and the fourth electrode plate decreases while a spacing the third electrode plate and the fourth electrode plate increases, wherein the first rotation axis and the second rotation axis are mutually perpendicular; wherein the processing unit is configured to collectively determine a spatial rotation angle of the prism carrier based on the capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate and a capacitance signal generated by the capacitor formed by the third electrode plate and the fourth electrode plate.
17 . The photographing module according to claim 16 , wherein: a number of third electrode plates is even, and the third electrode plates are symmetrically arranged about a first plane where the second rotation axis of the prism carrier is located, the first plane being perpendicular to a plane where the third electrode plates are located; a number of fourth electrode plates is even, and the fourth electrode plates are symmetrically arranged about the first plane; the third electrode plates are in one-to-one correspondence with the fourth electrode plates, and each respective third electrode plate of the third electrode plates and a respective fourth electrode plate of the fourth electrode plates forms a capacitor.
18 . The photographing module according to claim 13 , further comprising: a third electrode plate, located on the surface of the prism base; and a fourth electrode plate, located on the surface of the prism carrier and disposed opposite to the third electrode plate, wherein the third electrode plate and the fourth electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a second rotation axis, either an opposing area between the third electrode plate and the fourth electrode plate increases while a spacing the third electrode plate and the fourth electrode plate decreases, or an opposing area the third electrode plate and the fourth electrode plate decreases while a spacing the third electrode plate and the fourth electrode plate increases, wherein the first rotation axis and the second rotation axis are mutually perpendicular; wherein the processing unit is configured to collectively determine a spatial rotation angle of the prism carrier based on the capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate and a capacitance signal generated by the capacitor formed by the third electrode plate and the fourth electrode plate.
19 . The photographing module according to claim 12 , wherein a plane where the first electrode plate is located and a plane where the second electrode plate is located are both parallel to the first rotation axis.
20 . The photographing module according to claim 12 , wherein: a part of an orthographic projection of the first electrode plate toward the second electrode plate falls beyond the second electrode plate, and a part of an orthographic projection of the second electrode plate toward the first electrode plate falls beyond the first electrode plate.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of PCT Patent Application No. PCT/CN2025/101179, entitled “PRISM MOTOR, METHOD FOR DETECTING A ROTATION ANGLE OF A PRISM MOTOR, AND PHOTOGRAPHING MODULE,” filed Jun. 16, 2025, which claims priority to Chinese Patent Application No. CN202411572917.9, entitled “PRISM MOTOR, METHOD FOR DETECTING A ROTATION ANGLE OF A PRISM MOTOR, AND PHOTOGRAPHING MODULE,” filed on Nov. 5, 2024, which is incorporated by reference herein in its entirety. TECHNICAL FIELD The various embodiments described in this document relate in general to the field of camera technology, and more specifically to a prism motor, a method for detecting a rotation angle of a prism motor, and a photographing module. BACKGROUND Currently, a periscope photographing module typically uses a prism to refract incident light. By folding the incident light, a focal length of the photographing module is extended, thereby enhancing a zoom capability of the photographing module. During image acquisition using the photographing module, a propagation angle of the incident light can be changed by rotating a prism carrier in the prism motor, thus altering an imaging effect of the photographing module. A rotation angle of the prism carrier is usually detected by a built-in Hall sensor or a driver chip with Hall detection function. However, the prism rotation angle detection function in current periscope photography modules has at least the following drawbacks. The Hall sensor or driver chip with Hall detection function requires cooperation with a corresponding magnet to achieve angle measurement. Arranging the Hall sensor and corresponding magnet inside the prism motor occupies a large internal space of the motor, which is detrimental to miniaturization of the motor. On the other hand, given a fixed internal space of the motor, the Hall sensor and magnet occupying a large space also restrict a volume of the driving module for the prism motor, thereby being detrimental to improving driving capability of the prism motor. SUMMARY Embodiments of the present disclosure provide a prism motor, a method for detecting a rotation angle of the prism motor, and a photographing module, which saves internal volume occupied within the prism motor for implementing detection of a rotation angle of the prism motor, facilitates miniaturization of the prism motor, and enhances effectiveness in detecting a deviation angle of the prism carrier. To solve the above technical problem, embodiments of the present disclosure provide a prism motor, including: a prism base, a prism carrier, a first electrode plate, a second electrode plate, and a processing unit. The prism carrier is spaced apart from the prism base, where the prism carrier is rotatable relative to the prism base. The first electrode plate is located on a surface of the prism base. The second electrode plate is located on a surface of the prism carrier and disposed opposite to the first electrode plate, where the first electrode plate and the second electrode plate form a capacitor, and in a case where the prism carrier rotates in one direction about a first rotation axis, either an opposing area between the first electrode plate and the second electrode plate increases while a spacing between the first electrode plate and the second electrode plate decreases, or an opposing area between the first electrode plate and the second electrode plate decreases while a spacing between the first electrode plate and the second electrode plate increases. The processing unit is configured to determine a rotation angle of the prism carrier based on a capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate. The embodiments of the present disclosure further provide a method for detecting a rotation angle of a prism motor, applied to the above prism motor. The method includes: determining an initial capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate at an initial position of the prism carrier; determining a current capacitance signal upon a change in capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate; and determining a rotation angle of the prism carrier based on a difference between the current capacitance signal and the initial capacitance signal. The embodiments of the present disclosure further provide a photographing module, including: the above prism motor, a lens, and a photosensitive chip, where incident light entering the photographing module is reflected by the prism motor, passes through the lens, and reaches the photosensitive chip. Compared with the related art, in the embodiments of the present disclosure, the first electrode plate is disposed on the prism base, the second electrode plate is disposed on the prism carrier, the capacitor formed by the first electrode plate and th