Lissajous optical fiber scanner with double driving parts
By designing a dual-drive Lissajous fiber optic scanner and utilizing a combination of cylindrical and sheet-shaped piezoelectric actuators, the vibration coupling problem of the Lissajous scanner was solved, achieving uniform scanning effect and high yield, while reducing processing difficulty and precision requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2026-04-07
AI Technical Summary
When existing Lissajous scanners utilize natural frequencies close to each other in two directions, vibration coupling effects are easily generated, leading to scanning trajectory distortion and making it difficult to guarantee processing accuracy and yield.
Design a dual-drive Lissajous fiber optic scanner. By combining a cylindrical piezoelectric actuator and a sheet piezoelectric actuator, the natural frequency difference in the two directions is ensured to be appropriate, vibration coupling is avoided, and the manufacturing difficulty and accuracy requirements are reduced.
It achieves uniformity and density in scanning results, improves processing efficiency and yield, avoids vibration coupling, and reduces processing difficulty and precision requirements.
Smart Images
Figure CN224096079U_ABST
Abstract
Description
[0001] This application is a divisional application of Chinese Patent Application No. 2024232650125, filed with the Chinese Patent Office on December 30, 2024, entitled "A Dual-Drive Lissajous Fiber Optic Scanner", the entire contents of which are incorporated herein by reference. Technical Field
[0002] This application relates to the field of fiber optic scanner structure technology, and in particular to a dual-drive Lissajous fiber optic scanner. Background Technology
[0003] A fiber optic scanner is a display technology that uses a scanning driver to control the oscillation of an optical fiber while simultaneously emitting light. It is primarily used in fiber optic scanning display technology, fiber optic scanning endoscopy technology, and fiber optic scanning radar. When applied to image display, fiber optic scanners produce images with sharp, saturated colors, high contrast, high brightness, and a very small structural size.
[0004] Fiber optic scanners utilize the principle of mechanical resonance to enable a large scanning range for the fiber optic cantilever. Scanning methods of the scanning driver can be categorized into helical scanning, grid scanning, and Lissajous scanning. Lissajous scanning micro-piezoelectric scanning devices typically have driving sections in two directions, driving the scanning device to vibrate simultaneously in both directions. In Lissajous scanning, the closer the driving frequencies in the two directions, the closer the uniformity (density) of the scanning grid in both directions. Theoretically, the closer the driving frequencies in these two directions, the better. However, the closer the natural frequencies used by the scanner in the two directions, the more pronounced the vibration coupling effect becomes, which degrades the scanning trajectory, causing uncontrolled components in the scanning trajectory and resulting in image distortion that is difficult to completely eliminate through post-processing. Therefore, the natural frequencies used by the Lissajous scanner in the two directions should ideally have a precise difference range, avoiding both excessively small differences that cause coupling effects and excessively large differences that lead to unsatisfactory uniformity.
[0005] The manufacturing of Lissajous scanners, which utilize the inherent frequencies in both directions with precise differences, requires extremely high processing accuracy, making it difficult to guarantee both the cost of processing equipment and the yield rate. Utility Model Content
[0006] This application provides a dual-drive Lissajous fiber optic scanner to reduce processing difficulty and improve processing yield.
[0007] To achieve the aforementioned objectives, this application provides a dual-drive Lissajous fiber optic scanner.
[0008] It includes a cylindrical piezoelectric actuator, a sheet-shaped piezoelectric actuator fixedly connected to the cylindrical piezoelectric actuator, and an optical fiber fixedly mounted on the sheet-shaped piezoelectric actuator in a cantilever support manner.
[0009] The described cylindrical piezoelectric actuator includes a piezoelectric material cylindrical body. With the axial extension direction of the piezoelectric material cylindrical body as the front-to-back direction, the rear end of the piezoelectric material cylindrical body is fixedly connected to a base for support.
[0010] At least one of the inner and outer surfaces of the piezoelectric material cylindrical body is provided with a first inner electrode and a first outer electrode respectively. The portion of the piezoelectric material cylindrical body located between the corresponding first inner electrode and the first outer electrode is polarized along the thickness direction. The piezoelectric material located between the two is driven to extend and retract along the front-back direction by the first inner electrode and the corresponding first outer electrode, and the front end of the piezoelectric material cylindrical body is driven to vibrate left and right along the horizontal direction.
[0011] A sheet-shaped piezoelectric actuator is positioned parallel to the horizontal plane, located at the front of the piezoelectric material cylindrical body, with its rear end fixedly connected to the piezoelectric material cylindrical body. The front end of the sheet-shaped piezoelectric actuator vibrates vertically. An optical fiber is fixedly mounted at the front end of the sheet-shaped piezoelectric actuator using a cantilever support. The sheet-shaped piezoelectric actuator and the piezoelectric material cylindrical body overlap in the front-rear direction. Mounting grooves for connecting the sheet-shaped piezoelectric actuator are provided on both the left and right sides of the piezoelectric material cylindrical body. The rear end portion of the sheet-shaped piezoelectric actuator is inserted into the mounting groove and connected to the piezoelectric material. The cylindrical body is fixedly connected. The portion of the sheet-like piezoelectric actuator installed in the mounting groove and the portion of the piezoelectric material cylindrical body that overlaps with this portion of the sheet-like piezoelectric actuator in the front-to-back direction form an overlapping portion. The sheet-like piezoelectric actuator and the overlapping portion cause the natural frequency of the combination consisting of the piezoelectric material cylindrical body, the sheet-like piezoelectric actuator, and the optical fiber in the horizontal direction to be greater than the same order natural frequency of the combination in the vertical direction. Furthermore, there is a difference between the U-order natural frequency of the combination in the vertical direction, which is closest to its V-order natural frequency in the horizontal direction, and the V-order natural frequency in the horizontal direction. V is an integer ≥ 1, and U is an integer greater than V.
[0012] Specifically, by adjusting the shape and / or size parameters of the sheet-like piezoelectric actuator and the overlapping part, the natural frequencies of the combined part used in both directions are simultaneously close enough to ensure good scanning effect and a uniform and dense scanning grid; at the same time, they have a sufficient difference so that the vibration of the combined part in the two directions will not couple.
[0013] Optionally, the piezoelectric cylindrical body has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction, its outer contour is square, and its interior is provided with a central hole with a square or circular contour that is coaxial with the outer contour.
[0014] Alternatively, the piezoelectric cylindrical body has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction, its outer contour is square, and its interior is provided with a central hole with a square or circular contour that is coaxial with the outer contour.
[0015] The difference ensures that when the assembly performs a Lissajous scan under the drive signal, the vibrations of the assembly in the horizontal direction and the vibrations in the vertical direction will not couple.
[0016] Generally, the difference ranges from 10Hz to 12kHz. More preferably, the difference ranges from 1kHz to 10kHz. Specifically, the difference is selected based on the V-order natural frequency of the scanner arm in the horizontal direction. The difference is sufficient to ensure that the scanner arm has sufficient amplitude when the piezoelectric actuator performs Lissajous scanning under drive, and that the vibrations of the scanner arm in the horizontal and vertical directions do not couple. For those skilled in the art, selecting values based on the above description is a conventional technique in the field.
[0017] Optionally, the mounting groove can be located in the middle, upper or lower part of the left and right side walls of the piezoelectric material cylindrical body in the vertical direction, without limitation.
[0018] Optionally, the sheet-like piezoelectric actuator is a single piezoelectric actuator or a dual piezoelectric actuator.
[0019] Optionally, a first inner electrode and a first outer electrode are respectively provided on the inner and outer surfaces of either the left or right sides of the piezoelectric material cylindrical body. The portion of the piezoelectric material cylindrical body located between the first inner electrode and the corresponding first outer electrode is polarized along the thickness direction. The piezoelectric material located between the first inner electrode and the corresponding first outer electrode is driven to extend and retract in the front-back direction, driving the front end of the cylindrical body to vibrate left and right in the horizontal direction. The number of first inner electrodes or first outer electrodes can be one, two, or more.
[0020] Alternatively, the inner and outer surfaces of the left and right sides of the piezoelectric cylindrical body are respectively provided with corresponding first inner electrodes and first outer electrodes. The portion of the piezoelectric cylindrical body located between the first inner electrode and the corresponding first outer electrode is polarized along the thickness direction. The piezoelectric material located between the first inner electrode and the corresponding first outer electrode is driven to extend and retract in the front-back direction, while the piezoelectric materials on the left and right sides extend and retract synchronously in opposite directions with equal length, driving the front end of the cylindrical body to vibrate left and right in the horizontal direction. The number of first inner electrodes or first outer electrodes can be one, two, or more.
[0021] In a further preferred embodiment, when the inner and outer surfaces of the left and right sides of the piezoelectric material cylindrical body are respectively provided with a first inner electrode and a corresponding first outer electrode, the first inner electrodes on the left and right sides of the piezoelectric material cylindrical body are symmetrically arranged so as to drive the piezoelectric material cylindrical body to vibrate accurately in the horizontal direction without generating a vertical displacement component.
[0022] One or more technical solutions in this application have at least the following technical effects or advantages:
[0023] This application eliminates the need for the piezoelectric actuator of the Lissajous scanner to have a specific difference in its natural frequency in the two driving directions, thus avoiding coupling of vibrations in the two driving directions and reducing the requirements for processing difficulty and precision. More preferably, this application allows the piezoelectric material cylindrical body to have the same or similar natural frequencies in the two driving directions, and allows the piezoelectric material cylindrical body itself to be a rotationally symmetric structure. This further reduces the processing difficulty of the piezoelectric actuator of the Lissajous scanner, resulting in a significant improvement in processing efficiency and yield. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of this utility model;
[0025] Figure 2 This is a schematic diagram of the overlapping structure in the front-to-back direction;
[0026] Figure 3 This is a schematic diagram of another embodiment of the present invention. Detailed Implementation
[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0028] Example:
[0029] Combination Figure 1 , Figure 2 As shown, a dual-drive Lissajous fiber optic scanner includes a cylindrical piezoelectric actuator, a sheet-like piezoelectric actuator 103 fixedly connected to the cylindrical piezoelectric actuator, and an optical fiber 104 fixedly mounted on the sheet-like piezoelectric actuator 103 in a cantilevered manner.
[0030] The cylindrical piezoelectric actuator includes a piezoelectric material cylindrical body 100. With the axial extension direction of the piezoelectric material cylindrical body 100 as the front-to-back direction, the rear end of the piezoelectric material cylindrical body 100 is fixedly connected to a base 200 for support.
[0031] At least one of the inner and outer surfaces of the piezoelectric material cylindrical body 100 is provided with a first inner electrode 1011 and a first outer electrode 1012 respectively. The portion of the piezoelectric material cylindrical body 100 located between the corresponding first inner electrode 1011 and the first outer electrode 1012 is polarized along the thickness direction. The piezoelectric material located between the first inner electrode 1011 and the corresponding first outer electrode 1012 is driven to extend and retract in the front-back direction, and the front end of the piezoelectric material cylindrical body 100 is driven to vibrate left and right in the horizontal direction.
[0032] A sheet-shaped piezoelectric actuator 103 is arranged parallel to the horizontal plane, located at the front of the piezoelectric material cylindrical body 100, and its rear end is fixedly connected to the piezoelectric material cylindrical body 100. The front end of the sheet-shaped piezoelectric actuator 103 vibrates in the vertical direction. An optical fiber 104 is fixedly arranged at the front end of the sheet-shaped piezoelectric actuator 103 in a cantilever support manner. The sheet-shaped piezoelectric actuator 103 and the piezoelectric material cylindrical body 100 have an overlapping portion 105 in the front-rear direction. The left and right sides of the piezoelectric material cylindrical body 100 are provided with mounting grooves 106 for connecting the sheet-shaped piezoelectric actuator 103. The rear end portion of the sheet-shaped piezoelectric actuator 103 is inserted into the mounting groove 106. A portion of the piezoelectric cylindrical body 100 fixedly connected to the piezoelectric material cylindrical body 100 and installed in the mounting groove 106, together with a portion of the piezoelectric material cylindrical body 100 overlapping with this portion of the piezoelectric actuating part 103 in the front-back direction, forms an overlapping portion 105. The piezoelectric actuating part 103 and the overlapping portion 105 ensure that the natural frequency of the assembly consisting of the piezoelectric material cylindrical body 100, the piezoelectric actuating part 103, and the optical fiber 104 is greater in the horizontal direction than the same-order natural frequency in the vertical direction. Furthermore, the U-order natural frequency, which is closest to its V-order natural frequency in the vertical direction, has a difference from the V-order natural frequency in the horizontal direction. In this embodiment, V-order is first-order, and U-order is second-order.
[0033] Of course, this is only the parameter selection for this embodiment. In other embodiments with similar structure types to this embodiment, V can also be an integer greater than 1, and U can be an integer greater than V.
[0034] Specifically, by adjusting the shape and / or size parameters of the sheet-like piezoelectric actuator 103 and the overlapping part 105, the natural frequencies of the combined part used in both directions are simultaneously close enough to ensure good scanning effect and have a uniform and dense scanning grid; at the same time, they have a sufficient difference so that the vibration of the combined part in both directions will not couple.
[0035] Optional, such as Figure 1 As shown, the piezoelectric material cylindrical body 100 has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction. Its outer contour is square, and its interior is provided with a central hole with a square or circular contour that is coaxial with the outer contour.
[0036] Alternatively, such as Figure 3 As shown, the piezoelectric material cylindrical body 100 has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction. Its outer contour is square, and its interior is provided with a central hole with a square or circular contour that is coaxial with the outer contour.
[0037] The difference ensures that when the assembly performs a Lissajous scan under the drive signal, the vibrations of the assembly in the horizontal direction and the vibrations in the vertical direction will not couple.
[0038] Generally, the difference ranges from 10Hz to 12kHz. More preferably, the difference ranges from 1kHz to 10kHz. Specifically, the difference is selected based on the V-order natural frequency of the scanner arm in the horizontal direction. The difference is sufficient to ensure that the scanner arm has sufficient amplitude when the piezoelectric actuator performs Lissajous scanning under drive, and that the vibrations of the scanner arm in the horizontal and vertical directions do not couple. For those skilled in the art, selecting values based on the above description is a conventional technique in the field.
[0039] Optionally, the mounting groove 106 may be located in the middle, upper or lower part of the left and right side walls of the piezoelectric material cylindrical body 100 in the vertical direction, without limitation.
[0040] Optionally, the sheet-shaped piezoelectric actuator 103 is a single piezoelectric actuator or a dual piezoelectric actuator.
[0041] Optionally, a first inner electrode 1011 and a first outer electrode 1012 are respectively provided on the inner and outer surfaces of either the left or right sides of the piezoelectric material cylindrical body 100. The portion of the piezoelectric material cylindrical body 100 located between the first inner electrode 1011 and the corresponding first outer electrode 1012 is polarized along the thickness direction. The piezoelectric material located between the first inner electrode 1011 and the corresponding first outer electrode 1012 is driven to extend and retract in the front-back direction, driving the front end of the cylindrical body 100 to vibrate left and right in the horizontal direction. The number of first inner electrodes 1011 or first outer electrodes 1012 can be one, two, or more.
[0042] Alternatively, the inner and outer surfaces of the left and right sides of the piezoelectric material cylindrical body 100 are respectively provided with correspondingly matched first inner electrodes 1011 and first outer electrodes 1012. The portion of the piezoelectric material cylindrical body 100 located between the first inner electrode 1011 and the corresponding first outer electrode 1012 is polarized along the thickness direction. The piezoelectric material located between the first inner electrode 1011 and the corresponding first outer electrode 1012 is driven to extend and retract in the front-back direction, and the piezoelectric materials on the left and right sides extend and retract synchronously in opposite directions with equal length, driving the front end of the cylindrical body 100 to vibrate left and right in the horizontal direction. The number of first inner electrodes 1011 or first outer electrodes 1012 can be one, two, or more.
[0043] More preferably, when the inner and outer surfaces of the piezoelectric material cylindrical body 100 on both sides are respectively provided with a first inner electrode 1011 and a corresponding first outer electrode 1012, the first inner electrodes 1011 on both sides of the piezoelectric material cylindrical body 100 are symmetrically arranged so as to drive the piezoelectric material cylindrical body 100 to vibrate accurately in the horizontal direction without generating a vertical displacement component.
[0044] This application eliminates the need for the piezoelectric actuator of the Lissajous scanner to have a specific difference in its natural frequency in the two driving directions, thus avoiding coupling of vibrations in the two driving directions and reducing the processing difficulty and accuracy requirements. More preferably, this application allows the piezoelectric material cylindrical body 100 to have the same or similar natural frequencies in the two driving directions, and allows the piezoelectric material cylindrical body 100 itself to be a rotationally symmetric structure. This further reduces the processing difficulty of the piezoelectric actuator of the Lissajous scanner, resulting in a significant improvement in processing efficiency and yield.
[0045] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The words “comprising” or “including” do not exclude the presence of elements or steps not listed in the claims. The words “a” or “an” preceding an element do not exclude the presence of a plurality of such elements. The use of the words first, second, and third, etc., does not indicate any order and these words can be interpreted as names.
[0046] All features disclosed in this specification, except for mutually exclusive features, can be combined in any way.
[0047] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.
Claims
1. A dual-drive Lissajous fiber optic scanner, characterized in that, It includes a cylindrical piezoelectric actuator, a sheet-shaped piezoelectric actuator fixedly connected to the cylindrical piezoelectric actuator, and an optical fiber fixedly mounted on the sheet-shaped piezoelectric actuator in a cantilever support manner. The described cylindrical piezoelectric actuator includes a piezoelectric material cylindrical body. With the axial extension direction of the piezoelectric material cylindrical body as the front-to-back direction, the rear end of the piezoelectric material cylindrical body is fixedly connected to a base for support. At least one of the inner and outer surfaces of the piezoelectric material cylindrical body is provided with a first inner electrode and a first outer electrode respectively. The portion of the piezoelectric material cylindrical body located between the corresponding first inner electrode and the first outer electrode is polarized along the thickness direction. The piezoelectric material located between the two is driven to extend and retract along the front-back direction by the first inner electrode and the corresponding first outer electrode, and the front end of the piezoelectric material cylindrical body is driven to vibrate left and right along the horizontal direction. A sheet-shaped piezoelectric actuator is positioned parallel to the horizontal plane, located at the front of the piezoelectric material cylindrical body, with its rear end fixedly connected to the piezoelectric material cylindrical body. The front end of the sheet-shaped piezoelectric actuator vibrates vertically. An optical fiber is fixedly mounted at the front end of the sheet-shaped piezoelectric actuator using a cantilever support. The sheet-shaped piezoelectric actuator and the piezoelectric material cylindrical body have overlapping portions in the front-rear direction. The left and right sides of the piezoelectric material cylindrical body are provided with mounting grooves for connecting the sheet-shaped piezoelectric actuator. The rear end portion of the sheet-shaped piezoelectric actuator is inserted into the mounting grooves and fixedly connected to the piezoelectric material cylindrical body. The portion of the sheet piezoelectric actuator installed in the mounting groove and the piezoelectric material cylindrical body portion that overlaps with this portion of the sheet piezoelectric actuator in the front-back direction form an overlapping portion. The sheet piezoelectric actuator and the overlapping portion cause the natural frequency of the combination portion consisting of the piezoelectric material cylindrical body, the sheet piezoelectric actuator and the optical fiber in the horizontal direction to be greater than the natural frequency of the same order in the vertical direction. Furthermore, the U-order natural frequency of the combination portion in the vertical direction, which is closest to its V-order natural frequency in the horizontal direction, has a difference between it and the V-order natural frequency in the horizontal direction, where V is an integer ≥ 1 and U is an integer greater than V.
2. The dual-drive Lissajous fiber optic scanner as described in claim 1, characterized in that, The piezoelectric cylindrical body has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction. Its outer contour is square, and its interior has a central hole with a square or circular contour that is coaxial with the outer contour.
3. A dual-drive Lissajous fiber optic scanner as described in claim 1, characterized in that, The piezoelectric cylindrical body has the same natural frequency in the horizontal direction and the same natural frequency in the vertical direction. Its outer contour is square, and its interior has a central hole with a square or circular contour that is coaxial with the outer contour.
4. A dual-drive Lissajous fiber optic scanner as described in claim 3, characterized in that, The difference ensures that when the assembly performs a Lissajous scan under the drive signal, the vibrations of the assembly in the horizontal direction and the vibrations in the vertical direction will not couple.
5. A dual-drive Lissajous fiber optic scanner as described in claim 1 or 4, characterized in that, The difference range is 10Hz to 12KHz.
6. A dual-drive Lissajous fiber optic scanner as described in claim 5, characterized in that, The difference range is 1kHz to 10kHz.
7. A dual-drive Lissajous fiber optic scanner as described in claim 1, characterized in that, The inner and outer surfaces of either the left or right sides of the piezoelectric cylindrical body are respectively provided with a first inner electrode and a first outer electrode that are correspondingly matched. The portion of the piezoelectric cylindrical body located between the first inner electrode and the corresponding first outer electrode is polarized along the thickness direction. The piezoelectric material located between the two is driven by the first inner electrode and the corresponding first outer electrode to extend and retract in the front-back direction, driving the front end of the cylindrical body to vibrate left and right in the horizontal direction.
8. A dual-drive Lissajous fiber optic scanner as described in claim 1, characterized in that, The inner and outer surfaces of the left and right sides of the piezoelectric cylindrical body are respectively provided with corresponding first inner electrodes and first outer electrodes. The portion of the piezoelectric cylindrical body located between the first inner electrode and the corresponding first outer electrode is polarized along the thickness direction. The piezoelectric material located between the first inner electrode and the corresponding first outer electrode is driven to extend and retract in the front-back direction. The piezoelectric materials on the left and right sides extend and retract synchronously in opposite directions with equal length, driving the front end of the cylindrical body to vibrate left and right in the horizontal direction.
9. A dual-drive Lissajous fiber optic scanner as described in claim 8, characterized in that, The first inner electrodes on the left and right sides of the piezoelectric cylindrical body are symmetrically arranged.