Lissajous optical fiber scanner with double driving parts
By adjusting the shape and size parameters of the support plate, a dual-drive Lissajous fiber optic scanner was designed, which solved the problem of vibration coupling effect in Lissajous scanners and achieved efficient processing and improved yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU IDEALSEE TECH
- Filing Date
- 2024-12-30
- Publication Date
- 2026-05-15
AI Technical Summary
When existing Lissajous scanners utilize natural frequencies close in two directions, they are prone to vibration coupling effects, leading to scanning trajectory distortion and making it difficult to guarantee processing accuracy and yield.
A dual-drive Lissajous fiber optic scanner is designed. By adjusting the shape and size parameters of the support plate, the natural frequencies of the combined part in two directions are made close but have a sufficient difference to avoid vibration coupling. At the same time, the rigidity of the support column is used to isolate vibration interference, reducing the processing difficulty and accuracy requirements.
It achieves excellent scanning results and a uniform and dense scanning grid, improving processing efficiency and yield, while reducing processing size and precision requirements.
Smart Images
Figure CN224247986U_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, comprising a cylindrical body and an optical fiber. With the axis of the cylindrical body extending in the forward and backward direction, the rear end of the cylindrical body is fixedly connected to a base for support.
[0008] The cylindrical body includes support columns located at the four corners and four side plates connecting any two adjacent support columns. The upper side plate is a sheet-like piezoelectric actuator, and the length of the sheet-like piezoelectric actuator in the front-to-back direction is longer than the length of the other three side plates.
[0009] The rear half of the sheet piezoelectric actuator, together with four support columns and the remaining three side plates, forms a cylindrical overlapping section. The front end of the sheet piezoelectric actuator vibrates vertically, and the optical fiber is fixedly mounted at the front end of the sheet piezoelectric actuator in a cantilever support manner.
[0010] At least one of the inner and outer surfaces of the cylindrical overlapping portion is provided with a first inner electrode and a first outer electrode respectively. The portion of the cylindrical overlapping portion between the first inner electrode and the corresponding first outer electrode is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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.
[0011] The support plate ensures that the natural frequency of the combination of the cylindrical body and the optical fiber in the horizontal direction is greater than the natural frequency of the same order in the vertical direction, and that there is a difference between the natural frequency of the combination in the vertical direction that is closest to its V-order natural frequency in the horizontal direction and the natural frequency in the horizontal direction, where V is an integer greater than or equal to 1.
[0012] The assembly has first-order, second-order, third-order, ... N-order natural frequencies in the vertical direction. Among them, a certain natural frequency (e.g., U-order, where U is an integer greater than or equal to two) is closest to the V-order natural frequency of the assembly in the horizontal direction (V is less than U). In Lissajous scanning, the closer the driving frequencies in the two directions are, the closer the uniformity (density) of the scanning grid in the two directions will be. The more sampling points, the better, theoretically. However, the closer the natural frequencies used by the assembly in the two directions are, the more obvious the coupling effect will be. Therefore, this application uses the adjustment of the support plate shape structure and / or size parameters to make the natural frequencies of the assembly used in the two directions simultaneously satisfy the following: they are 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 assembly in the two directions will not produce coupling. Therefore, this application utilizes the adjustment of the support plate's shape and / or dimensional parameters to ensure that the vibration frequency of the assembly in both directions meets the requirements of Lissajous scanning, thereby reducing the processing size and precision requirements of the cylindrical body, making the processing of the cylindrical body easier, the processing error easier to control, and the yield rate higher.
[0013] Meanwhile, the rigidity of the support column is greater than that of the side plate, and its design can isolate the mutual deformation interference between the side plates vibrating in the horizontal direction and the side plates vibrating in the vertical direction, thereby improving the scanning accuracy.
[0014] In this embodiment, V is of order one and U is of order two. Of course, this is only the parameter selection for this embodiment. In other embodiments with similar structures, V can also be an integer greater than 1, and U can be an integer greater than V.
[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 inner and outer surfaces of either the left or right sides of the cylindrical overlapping portion are respectively provided with correspondingly fitted first inner and first outer electrodes. The portion of the cylindrical overlapping portion located between the first inner electrode and the corresponding first outer electrode is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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 overlapping portion 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.
[0018] Alternatively, the inner and outer surfaces of both sides of the cylindrical overlapping portion are respectively provided with corresponding first inner electrodes and first outer electrodes. The portion of the cylindrical overlapping portion between the first inner electrode and the corresponding first outer electrode is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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 material portions on the upper and lower sides extend and retract synchronously in opposite directions and by the same length, driving the front end of the cylindrical overlapping portion to vibrate left and right in the horizontal direction. The number of first inner electrodes or first outer electrodes located on the same side can be one, two, or more.
[0019] More preferably, when the inner and outer surfaces of the left and right sides of the cylindrical overlapping portion 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 cylindrical overlapping portion are symmetrically arranged so as to drive the cylindrical overlapping portion to vibrate accurately in the horizontal direction without generating a displacement component in the vertical direction.
[0020] One or more technical solutions in this application have at least the following technical effects or advantages:
[0021] This application eliminates the need for a specific difference in the natural frequencies of the piezoelectric actuator in the two driving directions of a Lissajous scanner, thus avoiding coupling of vibrations in both directions and reducing the requirements for manufacturing difficulty and precision. By adjusting the shape and / or dimensional parameters of the sheet-like piezoelectric actuator, the vibration frequencies of the assembly in both directions meet the requirements of Lissajous scanning, reducing the size and precision requirements of the cylindrical body. This results in lower manufacturing difficulty, easier control of manufacturing errors, and higher yield, significantly improving manufacturing efficiency and yield. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the structure of this utility model;
[0023] Figure 2 This is a schematic diagram of the main structure of the cylindrical body. Detailed Implementation
[0024] 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.
[0025] Example:
[0026] Combination Figure 1 , Figure 2 As shown, a dual-drive Lissajous fiber optic scanner includes a cylindrical body and an optical fiber 104.
[0027] With the axial extension direction of the cylindrical body as the front-to-back direction, the rear end of the cylindrical body is fixedly connected to the base 200 and supported by the base 200.
[0028] The cylindrical body includes support columns 105 located at the four corners and four side plates 106 connecting any two adjacent support columns 105. The upper side plate 106 is a sheet-like piezoelectric actuator 103, and the length of the sheet-like piezoelectric actuator 103 in the front-back direction is longer than the length of the other three side plates 106.
[0029] The rear half of the sheet piezoelectric actuator 103, together with four support columns 105 and the remaining three side plates 106, forms a cylindrical overlapping section. The front end of the sheet piezoelectric actuator 103 vibrates in the vertical direction. The optical fiber 104 is fixedly mounted on the front end of the sheet piezoelectric actuator 103 in a cantilever support manner.
[0030] At least one of the inner and outer surfaces of the cylindrical overlapping portion has a first inner electrode 1011 and a first outer electrode 1012 respectively, which are correspondingly fitted. The portion of the cylindrical overlapping portion between the first inner electrode 1011 and the corresponding first outer electrode 1012 is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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 to vibrate left and right in the horizontal direction.
[0031] The support plate makes the natural frequency of the combination of the cylindrical body and the optical fiber 104 in the horizontal direction greater than the natural frequency of the same order in the vertical direction, and makes the natural frequency of the combination in the vertical direction that is closest to its natural frequency of order V in the horizontal direction have a difference with the natural frequency in the horizontal direction, where V is an integer greater than or equal to 1.
[0032] The assembly has first-order, second-order, third-order, ... N-order natural frequencies in the vertical direction. Among them, a certain natural frequency (e.g., U-order, where U is an integer greater than or equal to two) is closest to the V-order natural frequency of the assembly in the horizontal direction (V is less than U). In Lissajous scanning, the closer the driving frequencies in the two directions are, the closer the uniformity (density) of the scanning grid in the two directions will be. The more sampling points, the better, theoretically. However, the closer the natural frequencies used by the assembly in the two directions are, the more obvious the coupling effect will be. Therefore, this application uses the adjustment of the support plate shape structure and / or size parameters to make the natural frequencies of the assembly used in the two directions simultaneously satisfy the following: they are 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 assembly in the two directions will not produce coupling. Therefore, this application utilizes the adjustment of the support plate's shape and / or dimensional parameters to ensure that the vibration frequency of the assembly in both directions meets the requirements of Lissajous scanning, thereby reducing the processing size and precision requirements of the cylindrical body, making the processing of the cylindrical body easier, the processing error easier to control, and the yield rate higher.
[0033] Meanwhile, the rigidity of the support column 105 is greater than that of the side plate 106. Its design can isolate the mutual deformation interference between the side plate 106 vibrating in the horizontal direction and the side plate 106 vibrating in the vertical direction, thereby improving the scanning accuracy.
[0034] In this embodiment, V is of order one and U is of order two. Of course, this is only the parameter selection for this embodiment. In other embodiments with similar structures, V can also be an integer greater than 1, and U can be an integer greater than V.
[0035] 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.
[0036] 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.
[0037] Optionally, a first inner electrode 1011 and a first outer electrode 1012 are respectively provided on the inner and outer surfaces of either side of the cylindrical overlapping portion. The portion of the cylindrical overlapping portion between the first inner electrode 1011 and the corresponding first outer electrode 1012 is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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 overlapping portion 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.
[0038] Alternatively, the inner and outer surfaces of both sides of the cylindrical overlapping portion are respectively provided with correspondingly fitted first inner electrodes 1011 and first outer electrodes 1012. The portion of the cylindrical overlapping portion between the first inner electrode 1011 and the corresponding first outer electrode 1012 is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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, while the piezoelectric material portions on the upper and lower sides extend and retract synchronously in opposite directions with equal length, driving the front end of the cylindrical overlapping portion to vibrate left and right in the horizontal direction. The number of first inner electrodes 1011 or first outer electrodes 1012 located on the same side can be one, two, or more.
[0039] More preferably, when the inner and outer surfaces of the left and right sides of the cylindrical overlapping portion are respectively provided with a first inner electrode 1011 and a corresponding first outer electrode 1012, the first inner electrodes 1011 on the left and right sides of the cylindrical overlapping portion are symmetrically arranged so as to drive the cylindrical overlapping portion to vibrate accurately in the horizontal direction without generating a displacement component in the vertical direction.
[0040] This application eliminates the need for a specific difference in the natural frequencies of the piezoelectric actuator in the two driving directions of the Lissajous scanner, thus avoiding coupling of vibrations in both directions and reducing the requirements for manufacturing difficulty and precision. By adjusting the shape and / or dimensional parameters of the sheet-like piezoelectric actuator 103, this application ensures that the vibration frequencies of the assembly in both directions meet the requirements of Lissajous scanning, reducing the size and precision requirements of the cylindrical body. This results in lower manufacturing difficulty, easier control of manufacturing errors, and higher yield, significantly improving manufacturing efficiency and yield.
[0041] 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.
[0042] All features disclosed in this specification, except for mutually exclusive features, can be combined in any way.
[0043] 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 body and optical fibers. With the axis of the cylindrical body extending in the front-to-back direction, the rear end of the cylindrical body is fixedly connected to a base for support. The cylindrical body includes support columns located at the four corners and four side plates connecting any two adjacent support columns. The upper side plate is a sheet-like piezoelectric actuator, and the length of the sheet-like piezoelectric actuator in the front-to-back direction is longer than the length of the other three side plates. The rear half of the sheet piezoelectric actuator, together with four support columns and the remaining three side plates, forms a cylindrical overlapping section. The front end of the sheet piezoelectric actuator vibrates vertically, and the optical fiber is fixedly mounted at the front end of the sheet piezoelectric actuator in a cantilever support manner. At least one of the inner and outer surfaces of the cylindrical overlapping portion is provided with a first inner electrode and a first outer electrode respectively. The portion of the cylindrical overlapping portion between the first inner electrode and the corresponding first outer electrode is a piezoelectric material portion polarized along the thickness direction. The piezoelectric material portion 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 support plate ensures that the natural frequency of the combination of the cylindrical body and the optical fiber in the horizontal direction is greater than the natural frequency of the same order in the vertical direction, and that there is a difference between the natural frequency of the combination in the vertical direction that is closest to its V-order natural frequency in the horizontal direction and the natural frequency in the horizontal direction, where V is an integer greater than or equal to 1.
2. The dual-drive Lissajous fiber optic scanner as described in claim 1, 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.
3. A dual-drive Lissajous fiber optic scanner as described in claim 1 or 2, characterized in that, The difference range is 10Hz to 12KHz.
4. A dual-drive Lissajous fiber optic scanner as described in claim 3, characterized in that, The difference range is 1kHz to 10kHz.
5. A dual-drive Lissajous fiber optic scanner as described in claim 1 or 2, characterized in that, The inner and outer surfaces of either side of the cylindrical overlapping part are respectively provided with a first inner electrode and a first outer electrode that are correspondingly matched. The part of the cylindrical overlapping part between the first inner electrode and the corresponding first outer electrode is a piezoelectric material part polarized along the thickness direction. The piezoelectric material part 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, and the front end of the cylindrical overlapping part is driven to vibrate left and right in the horizontal direction.
6. A dual-drive Lissajous fiber optic scanner as described in claim 1 or 2, characterized in that, The inner and outer surfaces of the left and right sides of the cylindrical overlapping part are respectively provided with corresponding first inner electrodes and first outer electrodes. The part of the cylindrical overlapping part between the first inner electrode and the corresponding first outer electrode is a piezoelectric material part polarized along the thickness direction. The piezoelectric material part 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. The piezoelectric material parts on the upper and lower sides extend and retract synchronously in opposite directions with equal length, driving the front end of the cylindrical overlapping part to vibrate left and right in the horizontal direction.
7. A dual-drive Lissajous fiber optic scanner as described in claim 6, characterized in that, The first inner electrodes on the left and right sides of the overlapping cylindrical part are symmetrically arranged.
8. A dual-drive Lissajous fiber optic scanner as described in claim 1, characterized in that, The rigidity of the support column is greater than that of the side plate.