Prism motor, prism motor rotation angle detection method and shooting module

Abstract

The embodiment of the invention relates to the technical field of camera shooting, and discloses a prism motor, a rotation angle detection method of the prism motor and a shooting module. According to the prism motor, a first polar plate is located on the surface of a prism base; the second polar plate is located on the surface of the prism carrier, and the second polar plate and the first polar plate are oppositely arranged; the first polar plate and the second polar plate form a capacitor, and under the condition that the prism carrier rotates around the first rotating shaft in a single direction, the opposite area between the first polar plate and the second polar plate is increased, and the distance between the first polar plate and the second polar plate is reduced; the opposite area between the first polar plate and the second polar plate is reduced, and the distance between the first polar plate and the second polar plate is increased; and the processing unit is used for determining the rotation angle of the prism carrier according to a capacitance signal generated by a capacitor formed by the first polar plate and the second polar plate. The miniaturization of the motor is facilitated, and the effect of detecting the deviation angle of the prism carrier is improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of camera technology, and in particular to a prism motor, a rotation angle detection method of a prism motor, and a shooting module. Background Art

[0002] At present, periscope camera modules usually use prism motors to refract incident light, and by folding the incident light, the focal length of the camera module is extended, thereby enhancing the zoom capability of the camera module. When using the camera module for image acquisition, the propagation angle of the incident light can be changed by rotating the prism carrier in the prism motor, thereby changing the imaging effect of the camera module. The rotation angle of the prism carrier is usually detected by a built-in Hall sensor or a driver chip with a Hall detection function.

[0003] The inventor found that the rotation angle detection function of the current periscope shooting module has at least the following shortcomings: the Hall sensor or the driver chip with the Hall detection function needs to cooperate with the corresponding sensing magnet to realize the angle measurement. The Hall sensor and the corresponding magnet are set inside the prism motor, which will occupy a large internal space of the motor, which is not conducive to the miniaturization of the motor. On the other hand, when the internal space of the motor is fixed, the Hall sensor and the magnet occupy a large space, which will also limit the volume of the driving module used to drive the prism motor, which is not conducive to improving the driving ability of the prism motor. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a prism motor, a rotation angle detection method of a prism motor and a shooting module, which saves the internal volume of the prism motor occupied for detecting the rotation angle of the prism motor, is conducive to the miniaturization of the motor, and improves the effect of detecting the offset angle of the prism carrier.

[0005] To solve the above technical problems, an embodiment of the present invention provides a prism motor, comprising: a prism base; a prism carrier, the prism carrier is spaced apart from the prism base, and the prism carrier can rotate relative to the prism base; a first pole plate, the first pole plate is located on the surface of the prism base; a second pole plate, the second pole plate is located on the surface of the prism carrier, and the second pole plate is arranged opposite to the first pole plate; the first pole plate and the second pole plate form a capacitor, and when the prism carrier rotates in one direction around the first rotation axis, the facing area between the first pole plate and the second pole plate increases and the distance between the first pole plate and the second pole plate decreases, or the facing area between the first pole plate and the second pole plate decreases and the distance between the first pole plate and the second pole plate increases; a processing unit, the processing unit is used to determine the rotation angle of the prism carrier according to the capacitance signal generated by the capacitance formed by the first pole plate and the second pole plate.

[0006] An embodiment of the present invention also provides a method for detecting the rotation angle of a prism motor, which is applied to the above-mentioned prism motor, and the method includes: determining an initial capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate when the prism carrier is in an initial position; when the capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate changes, determining a current capacitance signal; and determining the rotation angle of the prism carrier based on the difference between the current capacitance signal and the initial capacitance signal.

[0007] An embodiment of the present invention further provides a shooting module, comprising the above-mentioned prism motor, lens and photosensitive chip; incident light entering the shooting module is reflected by the prism motor and then passes through the lens to reach the photosensitive chip.

[0008] Compared with the prior art, the embodiment of the present invention sets a first electrode plate on the prism base and a second electrode plate on the prism carrier, and uses the first electrode plate and the second electrode plate to form a capacitor, and determines the rotation angle of the prism carrier through the change of the capacitance signal. The use of a smaller electrode plate in the motor instead of the Hall sensor saves the internal volume of the prism motor occupied for the detection of the rotation angle of the prism motor, which is conducive to the miniaturization of the motor. In addition, when the prism carrier rotates in one direction, the facing area and the spacing between the first electrode plate and the second electrode plate will change at the same time, and the change of the facing area and the change of the spacing have the same effect on the capacitance signal, that is, the change of the facing area and the change of the spacing will lead to an increase in the capacitance signal, or the change of both will lead to a decrease in the capacitance signal. Therefore, the simultaneous change of the facing area and the spacing will make the capacitance signal change more under the same angle rotation condition, resulting in more sensitive detection of the prism carrier angle rotation, and improving the effect of detecting the prism carrier offset angle.

[0009] In addition, the number of the first plates is an even number, and the plurality of the first plates are symmetrically arranged based on the first rotation axis of the prism carrier; the number of the second plates is an even number, and the plurality of the second plates are symmetrically arranged based on the first rotation axis of the prism carrier; the first plates and the second plates correspond to each other one by one, and each pair of the first plates and the second plates forms a capacitor; the processing unit is used to determine the rotation angle of the prism carrier according to the capacitance signals generated by the plurality of capacitors formed by the first plates and the second plates. By increasing the number of plates and increasing the number of capacitors used to detect the rotation angle, the accuracy of the rotation angle detection can be further improved through comprehensive analysis of the capacitance signals of the plurality of groups of capacitors.

[0010] In addition, the first electrode plate is symmetrically arranged based on the second rotation axis of the prism carrier, and the second electrode plate is symmetrically arranged based on the second rotation axis of the prism carrier; wherein the first rotation axis and the second rotation axis are perpendicular to each other. When the prism motor is rotatable in multiple directions, by arranging the electrode plates into a symmetrical structure, it is possible to ensure that the degree of change of the capacitance signals of the multiple groups of capacitors formed by the multiple electrode plates is roughly the same during rotation, thereby facilitating the elimination of the influence of the rotation angles in other directions on the detection results as much as possible through subsequent calculations, thereby improving the accuracy of the calculation of the rotation angle in a single direction.

[0011] In addition, the length of the first electrode plate is greater than the length of the second electrode plate, wherein the direction of the length is consistent with the direction of the first rotation axis. This can reduce the influence of the change in the capacitance signal generated by the first electrode plate and the second electrode plate of the first rotation axis caused by the rotation angle in other directions (such as the second rotation axis).

[0012] In addition, the prism motor further includes: a third plate, the third plate being located on the surface of the prism base; a fourth plate, the fourth plate being located on the surface of the prism carrier, and the fourth plate being arranged opposite to the third plate; the third plate and the fourth plate forming a capacitor, when the prism carrier rotates in one direction around the second rotation axis, the area facing each other between the third plate and the fourth plate increases and the distance between the third plate and the fourth plate decreases, or the area facing each other between the third plate and the fourth plate decreases and the distance between the third plate and the fourth plate increases; wherein the first rotation axis and the second rotation axis are perpendicular to each other; a processing unit, the processing unit being used to jointly determine the rotation angle of the prism carrier in space according to the capacitance signal generated by the capacitance formed by the first plate and the second plate, and the signal generated by the capacitance formed by the third plate and the fourth plate. In this way, when the prism carrier can rotate in multiple directions, different plate structures can be designed for corresponding detection.

[0013] In addition, the number of the third pole plates is an even number, and the third pole plates are symmetrically arranged based on the second rotation axis of the prism carrier; the number of the fourth pole plates is an even number, and the fourth pole plates are symmetrically arranged based on the second rotation axis of the prism carrier; the third pole plates and the fourth pole plates correspond one to one, and each pair of third pole plates and fourth pole plates forms a capacitor.

[0014] In addition, the planes where the first pole plate and the second pole plate are located are both parallel to the first rotation axis, and the planes where the third pole plate and the fourth pole plate are located are both parallel to the second rotation axis.

[0015] In addition, a portion of the orthographic projection of the first electrode plate in a direction toward the second electrode plate falls outside the second electrode plate, and a portion of the orthographic projection of the second electrode plate in a direction toward the first electrode plate falls outside the first electrode plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0017] Figure 1 is a schematic diagram of the three-dimensional structure of a prism motor according to an embodiment of the present invention; Figure 2 is a schematic cross-sectional structure diagram of a prism motor according to an embodiment of the present invention; Figure 3 is a schematic structural diagram of a prism motor according to an embodiment of the present invention when the second pole plate rotates around the first rotation axis; Figure 4 This is a schematic structural diagram of a first pole plate and a second pole plate arrangement method of a prism motor according to an embodiment of the present solution; Figure 5 It is a structural schematic diagram of another arrangement of the first pole plate and the second pole plate of the prism motor according to the embodiment of the present solution; Figure 6 is a schematic diagram of the spatial position change of the second pole plate of the prism motor rotating around the first rotation axis according to the embodiment of the present solution; Figure 7 is a schematic diagram of simulation results of a prism motor according to an embodiment of the present solution; Figure 8 is a schematic diagram comparing the sizes of the first pole plate and the second pole plate of the prism motor according to the embodiment of the present solution; Fig. 9 is a schematic structural diagram of a prism motor according to an embodiment of the present invention when the second pole plate rotates around the second rotation axis; Fig.10 This is a structural bird's-eye view of a third pole plate and a fourth pole plate arrangement method of a prism motor according to an embodiment of the present solution; Fig.11 This is a structural bird's-eye view of another arrangement of the third and fourth pole plates of the prism motor according to the embodiment of the present solution; Fig.12 This is a structural bird's-eye view of another arrangement of the third and fourth pole plates of the prism motor according to the embodiment of the present solution; Fig.13 is a schematic diagram of the positional relationship between the first pole plate and the second pole plate pair in the prism motor according to the embodiment of the present solution; Fig.14 is a schematic diagram of a shape of a first pole plate and a second pole plate pair in a prism motor according to an embodiment of the present solution; Fig.15 is a schematic diagram of another shape of the first pole plate and the second pole plate pair in the prism motor according to the embodiment of the present solution; Fig.16 is a schematic diagram of another shape of the first pole plate and the second pole plate pair in the prism motor according to the embodiment of the present solution; Fig.17 is a flow chart of a method for detecting the rotation angle of a prism motor according to an embodiment of the present invention; Fig.18 It is a schematic diagram of the structure of the shooting module in the embodiment of this scheme. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, it can be understood by those skilled in the art that in the embodiments of the present invention, many technical details are provided to enable readers to better understand the present invention. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present invention can be implemented.

[0019] The following embodiments are divided for the convenience of description and shall not constitute any limitation on the specific implementation of the present invention. The embodiments may be combined with each other and referenced to each other without contradiction.

[0020] An embodiment of the present invention relates to a prism motor, such as Figure 1 to Figure 2 As shown, the prism motor includes: a prism base 100; a prism carrier 200, the prism carrier 200 is spaced apart from the prism base 100, and the prism carrier 200 can rotate relative to the prism base 100; a first electrode plate 301, the first electrode plate 301 is located on the surface of the prism base 100; a second electrode plate 302, the second electrode plate 302 is located on the surface of the prism carrier 200, and the second electrode plate 302 is arranged opposite to the first electrode plate 301; the first electrode plate 301 and the second electrode plate 302 form a capacitor, and the prism carrier 200 When rotating in one direction around the first rotation axis, the facing area between the first electrode plate 301 and the second electrode plate 302 increases and the distance between the first electrode plate 301 and the second electrode plate 302 decreases, or the facing area between the first electrode plate 301 and the second electrode plate 302 decreases and the distance between the first electrode plate 301 and the second electrode plate 302 increases; a processing unit, the processing unit is used to determine the rotation angle of the prism carrier 200 according to the capacitance signal generated by the capacitance formed by the first electrode plate 301 and the second electrode plate 302.

[0021] Compared with the prior art, the embodiment of the present invention sets a first electrode plate 301 on the prism base 100 and sets a second electrode plate 302 on the prism carrier 200, and uses the first electrode plate 301 and the second electrode plate 302 to form a capacitor, and determines the rotation angle of the prism carrier 200 through the change of the capacitance signal, thereby realizing compensation for the angle change caused by the shake. Using a smaller electrode plate in the motor instead of the Hall sensor saves the internal volume of the prism motor occupied by the implementation of the anti-shake technology, which is conducive to the miniaturization of the motor. In addition, when the prism carrier 200 rotates unidirectionally, the facing area and the spacing between the first electrode plate 301 and the second electrode plate 302 will be changed at the same time, and the change in the facing area and the change in the spacing have the same effect on the capacitance signal, that is, the change in the facing area and the change in the spacing will both lead to an increase in the capacitance signal, or the change in both will lead to a decrease in the capacitance signal. Therefore, the simultaneous change in the facing area and the spacing will make the amplitude of the capacitance signal change larger under the same angle of rotation conditions, resulting in more sensitive detection of the angle rotation of the prism carrier 200, thereby improving the effect of detecting the offset angle of the prism carrier 200.

[0022] In addition, if Figure 2 As shown, the prism base 100 includes: a base bottom 101 and a base side 102 , and the first electrode plate 301 can be arranged on the base bottom 101 and / or the base side 102 according to the rotation direction of the prism carrier 200 .

[0023] like Figure 1 and Figure 3 As shown, the X-axis direction is the direction in which the incident light enters the prism motor, the Z-axis direction is the direction in which the incident light enters the lens vertically after being reflected, and the Y-axis is perpendicular to the XZ plane. Taking the rotation of the prism carrier 200 around the first rotation axis (Y axis) as an example, the first electrode plate 301 is fixed on the prism base 100. Before the prism carrier 200 rotates, the position of the second electrode plate 302 is as follows: Figure 3 As shown by the solid line position, when the prism carrier 200 rotates around the first rotation axis (Y axis) by an angle θ, the position of the second electrode plate 302 is as shown in FIG. Figure 3 As shown in the dotted position, the facing area between the first electrode plate 301 and the second electrode plate 302 after rotation is reduced, and the average spacing between the first electrode plate 301 and the second electrode plate 302 is increased, resulting in a change in the capacitance signal corresponding to the capacitance formed by the first electrode plate 301 and the second electrode plate 302. The rotation angle θ of the second electrode plate 302 can be determined by the change in the capacitance signal. Since the second electrode plate 302 is fixed on the prism carrier 200, that is, the rotation angle of the second electrode plate 302 corresponds to the rotation angle of the prism carrier 200, the rotation angle of the prism carrier 200 can be obtained according to the rotation angle of the second electrode plate 302, thereby completing the compensation for the angle change of the prism carrier 200 caused by the jitter.

[0024] In addition, the number of first pole plates 301 is an even number, and the multiple first pole plates 301 are symmetrically arranged based on the first rotation axis of the prism carrier 200; the number of second pole plates 302 is an even number, and the multiple second pole plates 302 are symmetrically arranged based on the first rotation axis of the prism carrier 200; the first pole plates 301 and the second pole plates 302 correspond one to one, and each pair of first pole plates 301 and second pole plates 302 forms a capacitor; the processing unit is used to determine the rotation angle of the prism carrier 200 based on the capacitance signals generated by the multiple capacitors formed by the first pole plates 301 and the second pole plates 302.

[0025] Take the example that the number of the first electrode plate 301 and the second electrode plate 302 are both 2. Figures 4 to 5 As shown, the planes where the two first pole plates 301 and the two second pole plates 302 are located are both arranged parallel to the first rotation axis (Y axis), and the two first pole plates 301 are respectively located on both sides of the first rotation axis and are symmetrically arranged relative to the first rotation axis. The two second pole plates 302 are respectively located on both sides of the first rotation axis and are symmetrically arranged relative to the first rotation axis.

[0026] When the first electrode plate 301 is disposed on the bottom 101 of the base, the second electrode plate 302 is correspondingly disposed on the bottom of the prism carrier 200. In addition, the prism base 100 is a semi-enclosed structure having three side surfaces and a bottom surface. When the first electrode plate 301 is disposed on the rear side of the base in the side portion of the base, the second electrode plate 302 is disposed on the side of the prism opposite to the rear side of the base.

[0027] Below Figure 6 Taking the first electrode plate and the second electrode plate of the first rotating axis as an example, the capacitance calculation method caused by the rotation of the second electrode plate is specifically described, taking the capacitance calculation of the left electrode plate as an example: When the second electrode 302 rotates clockwise along the Y-axis, the average gap between the first electrode 301 and the second electrode 302 on the left side of the figure increases, and at the same time, the facing area S of the two decreases. The increase in the average gap and the decrease in the facing area S will jointly aggravate the decrease in capacitance. Therefore, this method can be used to accelerate the change of capacitance, thereby improving the sensitivity of capacitance.

[0028] The initial plane equation for the second electrode plate 302 on the left side of the figure is: = -Rcosα, , ; in, represents the X-axis coordinate value of the initial plane of the second electrode plate 302, represents the minimum Z-axis coordinate value of the initial plane of the left second electrode plate 302, represents the maximum Z-axis coordinate value of the initial plane of the second electrode plate 302 on the left; R represents the distance between the center of the initial plane of the second electrode plate and the origin O, α represents the angle between the line connecting the center of the initial plane of the second electrode plate and the origin O and the X-axis, and m represents the width of the second electrode plate.

[0029] The initial plane equation of the left second electrode plate 302 is: = -Rcosα-gap, , ; in, represents the X-axis coordinate value of the initial plane of the first electrode plate 301, represents the minimum Z-axis coordinate value of the initial plane of the left first electrode plate 301, Represents the maximum Z-axis coordinate value of the initial plane of the first electrode plate 301 on the left side; m represents the width of the first electrode plate (here, the first electrode plate and the second electrode plate are taken as the same width as an example. In actual application, the first electrode plate and the second electrode plate can be set to different widths); shift represents the offset between the first electrode plate and the second electrode plate in the width direction at the initial position.

[0030] When the prism carrier 200 rotates β degrees clockwise around the Y axis, the plane equation of the left second electrode plate 302 after rotation is: ; ; in, represents the Z-axis coordinate value of the second pole plate 302 after rotation, represents the X-axis coordinate value of the second electrode plate 302 after rotation, z represents the Z-axis coordinate value of the second electrode plate 302 before rotation, x represents the X-axis coordinate value of the second electrode plate 302 before rotation, α represents the angle between the center of the initial plane of the second electrode plate and the line connecting the origin O and the X-axis, and β represents the rotation angle of the prism carrier 200.

[0031] The above equation can be used to calculate the average distance between the first electrode plate 301 and the second electrode plate 302 on the left side of the figure after rotation. for: = - ; After the rotation, the coordinate range of the overlap of the first electrode plate 301 and the second electrode plate 302 on the left side in the Z-axis direction is: ; ; in, represents the maximum Z-axis coordinate value of the initial plane of the left second electrode plate 302 after rotating by an angle of β, represents the maximum Z-axis coordinate value of the initial plane of the left first electrode plate 301, represents the minimum Z-axis coordinate value of the initial plane of the left second electrode plate 302 after rotating by an angle of β, Represents the minimum Z-axis coordinate value of the initial plane of the left first electrode plate 301.

[0032] Assuming the length of the plate is L, the capacitance expression of the two plates after rotating by angle β is: ; in, is the dielectric constant of the medium between the first plate and the second plate.

[0033] According to the calculation method of the above capacitance expression, the corresponding capacitance signal is determined by rotating the Y axis by an angle of β for simulation calculation. The initial parameters of the configuration are shown in the following table:

[0034] According to the initial parameters configured above, the simulation results of the capacitance value change corresponding to the rotation angle β are obtained as follows: Figure 7 As shown in the figure, under normal use of the prism motor, the capacitance has good linearity within the range of ±1 degree (60 minutes) of the rotation angle β, and has good capacitance sensitivity, which is convenient for determining the change in the rotation angle according to the change in the capacitance signal. In addition, if the length of the electrode is increased, that is, the initial overlapping area is increased, the capacitance signal changes more significantly, and the capacitance sensitivity can be further increased.

[0035] In addition, the first electrode plate 301 is symmetrically arranged based on the second rotation axis (X axis) of the prism carrier 200, and the second electrode plate 302 is symmetrically arranged based on the second rotation axis of the prism carrier 200; wherein the first rotation axis and the second rotation axis are perpendicular to each other. That is, the first electrode plate and the second electrode plate are symmetrically arranged in pairs about the XY plane. In addition, the first electrode plate 301 and the second electrode plate 302 are symmetrical about the ZX plane. While the prism motor rotates around the first rotation axis, it can also rotate around the second rotation axis. By setting the electrode plate as a central symmetrical structure, it is ensured that it is symmetrical relative to the first rotation axis and the second rotation axis. When the prism motor rotates around the axis, the capacitance signal changes of the multiple capacitors formed by the electrode plates of the symmetrical structure can be made to be roughly the same, thereby facilitating the elimination of the influence of the rotation angles in other directions on the detection results as much as possible through subsequent calculations, thereby improving the accuracy of the calculation of the rotation angle in a single direction.

[0036] Specifically, the first electrode plate and the second electrode plate are arranged symmetrically about the ZX plane as follows: Taking the number of the first electrode plate 301 and the second electrode plate 302 as 2 as an example, the two first electrode plates 301 are respectively located on both sides of the first rotation axis Y axis, and the Y axis does not coincide with the central axis of the first electrode plate, that is, the two first electrode plates are symmetrical about the Y axis, but the single first electrode plate is asymmetrical about the Y axis. The central axes of the two first electrode plates 301 coincide with the second rotation axis Z axis, that is, each first electrode plate is arranged symmetrically about the Z axis. Similarly, the second electrode plates 302 are respectively located on both sides of the first rotation axis Y axis, and the Y axis does not coincide with the central axis of the second electrode plate 302, that is, the two second electrode plates 302 are symmetrical about the Y axis, but the single second electrode plate 302 is asymmetrical about the Y axis. The central axes of the two second electrode plates 302 coincide with the second rotation axis Z axis, that is, each second electrode plate 302 is arranged symmetrically about the Z axis.

[0037] After determining the capacitance signals C1 and C2 generated by the electrode pair consisting of two pairs of first electrodes and second electrodes corresponding to the first rotation axis (Y axis), the final capacitance signal can be calculated by formula C1-C2. Since the rotation angle around the first rotation axis will cause the changes of capacitance signals C1 and C2 to be negatively correlated, that is, the decrease of C1 and the increase of C2, or the increase of C1 and the decrease of C2, the final capacitance signal calculated by formula C1-C2 can superimpose the two capacitance signals C1 and C2, thereby improving the capacitance sensitivity. On the other hand, by calculating the final capacitance by formula C1-C2, the change of capacitance signal caused by the rotation angle around the second rotation axis (X axis) can be eliminated to a certain extent. Rotation around the second rotation axis will have a positive correlation with the change of capacitance signals C1 and C2, that is, the decrease of C1 and the decrease of C2, or the increase of C1 and the increase of C2. Therefore, by calculating the final capacitance by formula C1-C2, the influence of rotation around the second rotation axis on capacitance signals C1 and C2 can be eliminated to a certain extent.

[0038] In addition, in addition to using the above formula to superimpose multiple capacitance signals, other formulas can also be used for comprehensive analysis, such as using (C1-C2) / (C1+C2) to perform differential processing on the results of multiple capacitance signals. In actual applications, other processing can be performed on the obtained capacitance signal according to the capacitance detection situation, such as correction or denoising of the capacitance signal, etc., to eliminate noise that affects the accuracy of the calculation results caused by environmental factors or human operation factors.

[0039] In addition, when the prism carrier 200 rotates only around the second rotation axis, the size of the facing area between the first electrode plate 301 and the second electrode plate 302 remains unchanged as much as possible. In this way, when the prism carrier 200 rotates around the second rotation axis, the facing area between the two electrode plates remains almost unchanged, and only the average spacing changes. Therefore, the influence of the rotation around the second rotation axis on the change of the capacitance signal between the first electrode plate 301 and the second electrode plate 302 can be reduced, and the change of the capacitance signal between the first electrode plate 301 and the second electrode plate 302 is more likely to correspond to the change in the angle of the rotation of the first rotation axis. Figure 8 As shown, the area sizes of the opposing surfaces between the first electrode plate 301 and the second electrode plate 302 can be set to different sizes, the area of ​​the first electrode plate in the opposing surface is set to be larger than the area of ​​the second electrode plate in the opposing surface, the width of the first electrode plate is larger than the width of the second electrode plate, and the direction of the width is consistent with the direction of the first rotation axis. Fig. 9 As shown, when the prism carrier is within the rated rotation travel range ±γ around the second rotation axis (X axis), the plate boundaries of the second electrode plate 302 in the width direction do not move beyond the plate boundaries of the first electrode plate 301 in the width direction, and the facing area of ​​the first electrode plate and the second electrode plate is almost unchanged.

[0040] In addition, the prism motor further includes: a third plate 303, the third plate is located on the surface of the prism base 100; a fourth plate 304, the fourth plate is located on the surface of the prism carrier 200, and the fourth plate is arranged opposite to the third plate; the third plate and the fourth plate form a capacitor, and when the prism carrier 200 rotates in one direction around the second rotation axis, the area facing each other between the third plate and the fourth plate increases and the distance between the third plate and the fourth plate decreases, or the area facing each other between the third plate and the fourth plate decreases and the distance between the third plate and the fourth plate increases; wherein the first rotation axis and the second rotation axis are perpendicular to each other; and a processing unit, the processing unit is used to determine the rotation angle of the prism carrier 200 in space according to the capacitance signal generated by the capacitance formed by the first plate 301 and the second plate 302, and the signal generated by the capacitance formed by the third plate 303 and the fourth plate 304. In this way, when the prism carrier 200 can rotate in multiple directions, different plate structures can be designed for corresponding detection.

[0041] like Figures 10 to 12 As shown, when the rotation axis is the X axis, the third pole plate 303 and the fourth pole plate 304 can be arranged at different positions of the prism motor, such as Fig.10 As shown, the third electrode plate 303 can be disposed on the left side of the base side portion 102 of the prism base 100, and the fourth electrode plate 304 is disposed on the left side of the prism carrier 200. Fig.11As shown, the third electrode plate 303 can be disposed on the right side of the base side portion 102 of the prism base 100, and the fourth electrode plate 304 is disposed on the right side of the prism carrier 200. Fig.12 As shown, the third electrode plate 303 can be disposed on the illustrated rear side of the base side portion 102 of the prism base 100 , and the fourth electrode plate 304 is correspondingly disposed on the illustrated rear side of the prism carrier 200 .

[0042] In addition, the arrangement rules of the third electrode plate 303 and the fourth electrode plate 304 are partially the same as the arrangement rules of the first electrode plate 301 and the second electrode plate 302. For example, the number of the third electrode plates is an even number, and the third electrode plates are arranged symmetrically based on the rotation axis of the prism carrier 200; the number of the fourth electrode plates is an even number, and the fourth electrode plates are arranged symmetrically based on the rotation axis of the prism carrier 200; the third electrode plates and the fourth electrode plates correspond one to one, and each pair of the third electrode plates and the fourth electrode plates forms a capacitor. The arrangement of the third electrode plate and the fourth electrode plate is to detect the angle of rotation of the prism carrier 200 around the second rotation axis. The calculation method refers to the simulation results of the capacitance signal and the rotation angle generated by the first electrode plate 301 and the second electrode plate 302, which will not be repeated here.

[0043] In addition, if Fig.13 As shown, part of the orthographic projection of the first electrode plate 301 in the direction of the second electrode plate 302 falls outside the second electrode plate 302, and part of the orthographic projection of the second electrode plate 302 in the direction of the first electrode plate 301 falls outside the first electrode plate 301, and there is a certain offset shift in the orthographic projections between the two electrode plates. Similarly, part of the orthographic projection of the third electrode plate in the direction of the fourth electrode plate falls outside the fourth electrode plate, and part of the orthographic projection of the fourth electrode plate in the direction of the third electrode plate falls outside the third electrode plate, and there may also be a certain offset shift in the orthographic projections between the two electrode plates. In order to make the prism carrier 200 within the rated rotation range, the two capacitors respectively composed of the two first electrode plates 301 and the two second electrode plates 302 can both ensure that the facing area is negatively correlated with the change in the average spacing, and the above effect can be achieved by limiting the numerical range of shift. The rules for limiting the numerical range of shift are as follows: by Figure 6 Taking the first electrode plate 301 and the second electrode plate 302 as an example, the initial plane equation is calculated as above. Figure 6 The minimum initial Z coordinate of the second plate 302 on the left side is , the maximum initial Z coordinate is . And the plane rotation formula is: ; Use the plane rotation formula to get the minimum Z coordinate after rotation and the maximum Z coordinate after rotation . Through the formula shift>| - |, and shift>| - |, determine the value range of the shift value.

[0044] In addition, considering the compactness of the internal structure of the prism motor, the shapes of the first plate 301 and the second plate 302, as well as the shapes of the third plate 303 and the fourth plate 304 can be other shapes besides a rectangle. According to the occupation of the internal space of the prism motor, the plates can be arranged as follows: Fig.14 The triangular plate shown in Fig.15 The circular plate shown or Fig.16 The polygonal plates or curved plates such as the trapezoidal plates shown are combined in pairs.

[0045] The embodiment of the present invention also relates to a rotation angle detection method of a prism motor, which is applied to the above-mentioned prism motor, such as Fig.17 As shown, the rotation angle detection method includes: Step 1701: determining an initial capacitance signal generated by a capacitor formed by a first electrode plate and a second electrode plate at an initial position of a prism carrier; Step 1702: when a capacitance signal generated by a capacitor formed by the first electrode plate and the second electrode plate changes, determining a current capacitance signal; Step 1703: Determine the rotation angle of the prism carrier according to the difference between the current capacitance signal and the initial capacitance signal.

[0046] Compared with the prior art, the embodiment of the present invention uses a smaller plate in the motor instead of a Hall sensor, and calculates the rotation angle of the motor by the change of the capacitance signal of the capacitor formed between the plates, which saves the internal volume of the prism motor and is conducive to the miniaturization of the motor. After determining the angle of rotation of the prism carrier, the above-mentioned angle rotation detection method can be used to achieve an anti-shake effect and control the prism carrier to rotate to a target angle. For example, the target angle is the angle required for jitter compensation, and the rotation of the prism carrier is controlled according to the difference between the current rotation angle and the target angle. Since the jitter occurs in real time during the shooting process, the jitter compensation control is also carried out in real time. After one compensation, the next round of compensation angle judgment and the process of controlling the rotation of the prism carrier are entered.

[0047] The calculation method of the corresponding relationship between the capacitance signal generated by the capacitor formed by the first electrode plate and the second electrode plate and the rotation angle is specifically described in the previous embodiment. Specifically, the rotation angle corresponding to different capacitance signals is determined based on the simulation curve generated based on the capacitance signal and the rotation angle simulation.

[0048] The step division of the above methods is only for clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the protection scope of the present invention. Adding insignificant modifications or introducing insignificant designs to the algorithm or process without changing the core design of the algorithm and process are all within the protection scope of the present invention.

[0049] Another feasible embodiment of the present invention relates to a shooting module, as shown in FIG18 , including the prism motor, lens and photosensitive chip as described above; the incident light entering the shooting module is reflected by the prism motor and then passes through the lens 400 to reach the photosensitive chip 500. Specifically, the incident light enters the shooting module through the light-transmitting sheet 201, and the propagation direction of the incident light is changed by the reflective lens 202 of the prism motor, so that the incident light can vertically penetrate the lens to reach the photosensitive chip.

[0050] Compared with the related art, the shooting module provided by the embodiment of the present invention is provided with the prism motor provided by the aforementioned embodiment. Therefore, it also has the technical effects provided by the aforementioned embodiment, which will not be elaborated here.

[0051] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A prism motor, characterized in that: include: Prism base; A prism carrier, wherein the prism carrier is spaced apart from the prism base and the prism carrier is rotatable relative to the prism base; A first electrode plate, the first electrode plate is located on a surface of the prism base; a second electrode plate, the second electrode plate is located on the surface of the prism carrier, and the second electrode plate is arranged opposite to the first electrode plate; the first electrode plate and the second electrode plate form a capacitor, and when the prism carrier rotates in one direction around the first rotation axis, the facing area between the first electrode plate and the second electrode plate increases and the distance between the first electrode plate and the second electrode plate decreases, or the facing area between the first electrode plate and the second electrode plate decreases and the distance between the first electrode plate and the second electrode plate increases; A processing unit, wherein the processing unit is used to determine the rotation angle of the prism carrier according to a capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate.

2. The prism motor according to claim 1, characterized in that: The number of the first pole plates is an even number, and the plurality of the first pole plates are symmetrically arranged based on the first rotation axis of the prism carrier; The number of the second pole plates is an even number, and the plurality of the second pole plates are symmetrically arranged based on the first rotation axis of the prism carrier; The first electrode plates and the second electrode plates correspond to each other one by one, and each pair of the first electrode plates and the second electrode plates forms a capacitor; The processing unit is used to determine the rotation angle of the prism carrier according to the capacitance signals generated by the multiple capacitors formed by the first electrode plate and the second electrode plate.

3. The prism motor according to claim 2, characterized in that: The first pole plate is symmetrically arranged based on the second rotation axis of the prism carrier, and the second pole plate is symmetrically arranged based on the second rotation axis of the prism carrier; wherein the first rotation axis and the second rotation axis are perpendicular to each other.

4. The prism motor according to claim 3, characterized in that: The length of the first electrode plate is greater than the length of the second electrode plate; wherein the direction defining the length is consistent with the direction of the first rotation axis.

5. The prism motor according to claim 1 or 2, characterized in that: Also includes: A third electrode plate, the third electrode plate is located on the surface of the prism base; a fourth electrode plate, the fourth electrode plate is located on the surface of the prism carrier, and the fourth electrode plate is arranged opposite to the third electrode plate; the third electrode plate and the fourth electrode plate form a capacitor, and when the prism carrier rotates in one direction around the second rotation axis, the facing area between the third electrode plate and the fourth electrode plate increases and the distance between the third electrode plate and the fourth electrode plate decreases, or the facing area between the third electrode plate and the fourth electrode plate decreases and the distance between the third electrode plate and the fourth electrode plate increases; wherein the first rotation axis and the second rotation axis are perpendicular to each other; A processing unit, the processing unit is used to jointly determine the angle of rotation of the prism carrier in space based on the capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate, and the signal generated by the capacitance formed by the third electrode plate and the fourth electrode plate.

6. The prism motor according to claim 5, characterized in that: The number of the third pole plates is an even number, and the third pole plates are symmetrically arranged based on the second rotation axis of the prism carrier; The number of the fourth pole plates is an even number, and the fourth pole plates are symmetrically arranged based on the second rotation axis of the prism carrier; The third electrode plates correspond to the fourth electrode plates one by one, and each pair of the third electrode plates and the fourth electrode plates forms a capacitor.

7. The prism motor according to claim 1, characterized in that: The planes where the first pole plate and the second pole plate are located are both parallel to the first rotation axis.

8. The prism motor according to claim 1, characterized in that: The orthographic projection of a portion of the first electrode plate in a direction toward the second electrode plate falls outside the second electrode plate, and the orthographic projection of a portion of the second electrode plate in a direction toward the first electrode plate falls outside the first electrode plate.

9. A method for detecting the rotation angle of a prism motor, applied to the prism motor as claimed in any one of claims 1 to 8, characterized in that: include: Determine an initial capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate when the prism carrier is in an initial position; When a capacitance signal generated by the capacitance formed by the first electrode plate and the second electrode plate changes, determining a current capacitance signal; The rotation angle of the prism carrier is determined according to the difference between the current capacitance signal and the initial capacitance signal.

10. A shooting module, characterized in that: include: The prism motor, lens and photosensitive chip as claimed in any one of claims 1 to 8; The incident light entering the shooting module is reflected by the prism motor and then passes through the lens to reach the photosensitive chip.

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