Lissajous scanner
By combining a sheet-like piezoelectric actuator and an overlapping part on the cantilever of the Lissajous scanner, and adjusting the natural frequency difference, the vibration coupling problem was solved, resulting in a Lissajous scanner with high yield and uniform scanning effect.
Patent Information
- Application Number
- CN202423313400.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-12-26
- Estimated Expiration
- 2034-12-30
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, making them difficult to manufacture and resulting in low yield.
A Lissajous scanner is designed by combining a sheet-like piezoelectric actuator and an overlapping part on the scanner cantilever. By adjusting its shape and size parameters, the natural frequencies in two directions are both close and have a sufficient difference, thus avoiding vibration coupling. A piezoelectric actuator with a regular shape is used to reduce the difficulty of processing.
It achieves a uniform and dense scanning mesh in two directions, reducing processing difficulty, improving yield, and avoiding vibration coupling effects.
Smart Images
Figure CN223728062U_ABST
Abstract
Description
[0001] This application is a divisional application of the Chinese patent application with the application number 2024232650252, the name of invention is "a Lissajous scanner", which was filed on December 30, 2024, and the whole content of the application is incorporated herein by reference. TECHNICAL FIELD
[0002] The present application relates to the technical field of optical fiber scanner structure, in particular to a Lissajous scanner. BACKGROUND
[0003] The optical fiber scanner is a display technology that uses a scanning driver to control the swing of an optical fiber while the optical fiber emits light rays. It is mainly used in the technical fields of optical fiber scanning display technology, optical fiber scanning endoscope technology, optical fiber scanning radar, etc. When the optical fiber scanner is applied to image display, the color of the pattern illuminated by this technology is sharp and saturated, the contrast is high, the brightness is high, and the structure is very small.
[0004] The optical fiber scanner uses the principle of mechanical resonance to make the cantilever of the optical fiber achieve a large scanning range. The scanning mode of the scanning driver can be divided into spiral scanning, grid scanning and Lissajous scanning. The micro piezoelectric scanning device of Lissajous scanning generally has two driving parts, which drive the scanning device to vibrate in two directions at the same time. The closer the driving frequencies of the two directions in Lissajous scanning, the closer the uniformity (density) of the scanning grid in the two directions. In theory, the closer the driving frequencies of the two directions, the better. However, the closer the inherent frequencies used by the scanner in the two directions, the more obvious the vibration coupling effect will be, which will worsen the scanning trajectory, cause uncontrollable components in the scanning trajectory and result in distortion of the scanning image, which is difficult to completely eliminate through post-processing. Therefore, the inherent frequencies used by the Lissajous scanner in the two directions should have a precise difference range, neither too small to cause coupling effect, nor too large to cause non-uniformity.
[0005] However, the Lissajous scanner that processes and manufactures inherent frequencies with a precise difference in the two directions requires extremely high processing precision, and neither the cost of processing equipment nor the yield can be guaranteed. Practical new type content
[0006] The present application provides a Lissajous scanner to reduce the processing difficulty and improve the processing yield.
[0007] In order to achieve the above application purposes, the present application provides a Lissajous scanner, which comprises a base, a first piezoelectric actuating part, a sheet piezoelectric actuating part and an optical fiber. The first piezoelectric actuating part is a one-dimensional scanning piezoelectric actuating part. The fixed end of the first piezoelectric actuating part is fixedly connected with the base. The free end of the first piezoelectric actuating part vibrates along a first direction. The free end of the first piezoelectric actuating part is the front end, and the fixed end of the first piezoelectric actuating part is the back end. The first direction is the left-right direction. The back end of the sheet piezoelectric actuating part is fixedly connected with the free end of the first piezoelectric actuating part. The sheet piezoelectric actuating part is arranged along a direction parallel to the horizontal plane. The sheet piezoelectric actuating part and the first piezoelectric actuating part have an overlapping part in the front-back direction. The front end of the sheet piezoelectric actuating part vibrates along the vertical direction. The optical fiber is fixedly arranged at the front end of the sheet piezoelectric actuating part in a cantilever support manner. The first piezoelectric actuating part, the sheet piezoelectric actuating part and the optical fiber constitute a scanner cantilever. The sheet piezoelectric actuating part and the overlapping part make the inherent frequency of the scanner cantilever in the horizontal direction greater than the same order inherent frequency of the scanner cantilever in the vertical direction, and make the scanner cantilever in the vertical direction have a difference between the certain order inherent frequency closest to the V order inherent frequency in the horizontal direction and the V order inherent frequency in the horizontal direction, V being an integer greater than or equal to 1.
[0008] The scanner cantilever has a first order inherent frequency, a second order inherent frequency, a third order inherent frequency, …, and an N order inherent frequency in the vertical direction. Among them, the inherent frequency of a certain order (for example, U order, U being an integer greater than or equal to two) is closest to the V order inherent frequency of the scanner cantilever in the horizontal direction (V is less than U). The closer the driving frequencies of the two directions in the Lissajous scanning are, the closer the uniformity (density) of the scanning grid in the two directions is, and the more the number of points is. In theory, the closer the driving frequencies of the two directions are, the better. However, the closer the inherent frequencies of the scanner cantilever used in the two directions are, the more obvious the coupling effect is. Therefore, the present application adjusts the shape structure and / or size parameters of the sheet piezoelectric actuating part and the overlapping part, so that the inherent frequencies of the scanner cantilever used in the two directions simultaneously meet the requirements of being close enough to ensure good scanning effect and having a uniform and dense scanning grid, and also meet the requirement of having a sufficient difference, so that the vibrations of the scanner cantilever in the two directions do not produce coupling.
[0009] Preferably, the first piezoelectric actuating part has the same or similar natural frequency in the left-right direction and the vertical direction. The first piezoelectric actuating part refers to the first piezoelectric actuating part itself, not including the sheet piezoelectric actuating part or other components such as optical fibers. The first piezoelectric actuating part that meets such requirements is a piezoelectric actuator with regular shape and rotational symmetry, which has low processing difficulty, easy to control processing error, and high yield. For example, a circular tube type piezoelectric actuator, a square tube type piezoelectric actuator, a circular rod type piezoelectric actuator, and a square rod type piezoelectric actuator. The sheet piezoelectric actuating part is also a conventional actuator with low processing difficulty. The present application combines two easily processed components to obtain a scanner suitable for Lissajous scanning and with guaranteed anti-coupling effect, which has lower processing difficulty and higher yield than the existing Lissajous scanner.
[0010] Therefore, the difference satisfies that the scanner cantilever has sufficient amplitude when the first piezoelectric actuating part performs Lissajous scanning under the driving of the driving signal, and the vibration of the scanner cantilever in the horizontal direction and the vertical direction does not produce coupling.
[0011] Generally, the difference ranges from 10 Hz to 12 KHz. Further preferably, the difference ranges from 1 KHz to 10 KHz. The value is selected according to the selected V-order natural frequency of the scanner cantilever in the horizontal direction. As long as the difference satisfies that the scanner cantilever has sufficient amplitude when the piezoelectric actuating part performs Lissajous scanning under the driving, and the vibration of the scanner cantilever in the horizontal direction and the vertical direction does not produce coupling, it is acceptable. For those skilled in the art, numerical selection according to the above description is a conventional technical means in the art.
[0012] The optical fiber is fixed on the upper surface or the lower surface of the support plate in a cantilever support manner or inside the support plate. The cantilever support means that the front end of the optical fiber beyond the front end of the support plate forms an optical fiber cantilever, and the part of the optical fiber located at the rear side of the optical fiber cantilever is fixedly connected with the support plate. As an embodiment in which the optical fiber is arranged inside the support plate, a mounting hole for accommodating the optical fiber is arranged in the support plate body, and the optical fiber is fixed in the mounting hole in a cantilever support manner.
[0013] The piezoelectric actuating part includes a circular tube type piezoelectric actuator, a square tube type piezoelectric actuator, a square rod type piezoelectric actuator, or a circular rod type piezoelectric actuator.
[0014] Optionally, the sheet piezoelectric actuating part is a single piezoelectric sheet actuator or a double piezoelectric sheet actuator.
[0015] One or more technical solutions in the present application have at least the following technical effects or advantages:
[0016] The application utilizes the regulation of the shape structure and / or size parameters of the sheet piezoelectric actuating part and the coincident part, so that the scanner cantilever inherent frequencies in two directions are simultaneously satisfied, which can be close enough to ensure good scanning effect, have uniform and dense scanning grid, and have enough difference, so that the vibration of the scanner cantilever in two directions will not be coupled.
[0017] Since the inherent frequency of the first piezoelectric actuating part in the left-right direction and the inherent frequency in the vertical direction are the same or similar, the first piezoelectric actuating part here refers to the first piezoelectric actuating part itself, and does not include the sheet piezoelectric actuating part or other components such as optical fibers. The first piezoelectric actuating part satisfying such requirements is a piezoelectric actuator with regular shape and rotational symmetry, which has low processing difficulty, easy control of processing error and high yield. BRIEF DESCRIPTION OF DRAWINGS
[0018] Figure 1 It is a structural schematic diagram of the application;
[0019] Figure 2 It is a structural schematic diagram of the coincident part;
[0020] Figure 3 It is a structural schematic diagram of the circular tube type piezoelectric actuator;
[0021] Figure 4 It is a structural schematic diagram of the square tube type piezoelectric actuator;
[0022] Figure 5 It is a structural schematic diagram of the square rod type piezoelectric actuator;
[0023] Figure 6 It is a structural schematic diagram of the circular rod type piezoelectric actuator. DETAILED DESCRIPTION
[0024] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.
[0025] As Figure 1As shown, a Lissajous scanner comprises a base 400, a first piezoelectric actuator 100, a sheet piezoelectric actuator 200 and an optical fiber 300. The first piezoelectric actuator 100 is a one-dimensional scanning piezoelectric actuator. The fixed end of the first piezoelectric actuator 100 is fixedly connected to the base 400. The free end of the first piezoelectric actuator 100 vibrates in a first direction. The free end of the first piezoelectric actuator 100 is the front end, and the fixed end of the first piezoelectric actuator 100 is the back end. The first direction is the left-right direction. The back end of the sheet piezoelectric actuator 200 is fixedly connected to the free end of the first piezoelectric actuator 100. The sheet piezoelectric actuator 200 is arranged in a direction parallel to the horizontal plane. The sheet piezoelectric actuator 200 and the first piezoelectric actuator 100 have a coincident portion 500 in the front-back direction. As shown, the front end of the sheet piezoelectric actuator 200 vibrates in the vertical direction. The optical fiber 300 is fixedly arranged at the front end of the sheet piezoelectric actuator 200 in a cantilever support manner. The first piezoelectric actuator 100, the sheet piezoelectric actuator 200 and the optical fiber 300 constitute a scanner cantilever. The sheet piezoelectric actuator 200 and the coincident portion 500 make the inherent frequency of the scanner cantilever in the horizontal direction greater than the same order inherent frequency of the scanner cantilever in the vertical direction. The scanner cantilever in the vertical direction has a first order inherent frequency, a second order inherent frequency, a third order inherent frequency, …, and an Nth order inherent frequency. There is a certain order (for example, U order, U is an integer greater than or equal to two) of inherent frequency closest to the Vth order inherent frequency of the scanner cantilever in the horizontal direction (V is less than U). The closer the driving frequencies in two directions in the Lissajous scanning are, the closer the uniformity (density) of the scanning grid in the two directions is, and the more the number of points is. In theory, the closer the driving frequencies in the two directions are, the better. However, the closer the inherent frequencies of the scanner cantilever used in the two directions are, the more obvious the coupling effect is. Therefore, the application adjusts the shape structure and / or size parameters of the sheet piezoelectric actuator 200 and the coincident portion 500, so that the inherent frequencies of the scanner cantilever used in the two directions simultaneously meet the requirements of being close enough to ensure good scanning effect and having a uniform and dense scanning grid, and also meet the requirement of having a sufficient difference to prevent the vibration of the scanner cantilever in the two directions from being coupled. Figure 2 As shown, the front end of the sheet piezoelectric actuator 200 vibrates in the vertical direction. The optical fiber 300 is fixedly arranged at the front end of the sheet piezoelectric actuator 200 in a cantilever support manner. The first piezoelectric actuator 100, the sheet piezoelectric actuator 200 and the optical fiber 300 constitute a scanner cantilever. The sheet piezoelectric actuator 200 and the coincident portion 500 make the inherent frequency of the scanner cantilever in the horizontal direction greater than the same order inherent frequency of the scanner cantilever in the vertical direction. The scanner cantilever in the vertical direction has a first order inherent frequency, a second order inherent frequency, a third order inherent frequency, …, and an Nth order inherent frequency. There is a certain order (for example, U order, U is an integer greater than or equal to two) of inherent frequency closest to the Vth order inherent frequency of the scanner cantilever in the horizontal direction (V is less than U). The closer the driving frequencies in two directions in the Lissajous scanning are, the closer the uniformity (density) of the scanning grid in the two directions is, and the more the number of points is. In theory, the closer the driving frequencies in the two directions are, the better. However, the closer the inherent frequencies of the scanner cantilever used in the two directions are, the more obvious the coupling effect is. Therefore, the application adjusts the shape structure and / or size parameters of the sheet piezoelectric actuator 200 and the coincident portion 500, so that the inherent frequencies of the scanner cantilever used in the two directions simultaneously meet the requirements of being close enough to ensure good scanning effect and having a uniform and dense scanning grid, and also meet the requirement of having a sufficient difference to prevent the vibration of the scanner cantilever in the two directions from being coupled.
[0026] As shown, the front end of the sheet piezoelectric actuator 200 vibrates in the vertical direction. The optical fiber 300 is fixedly arranged at the front end of the sheet piezoelectric actuator 200 in a cantilever support manner. The first piezoelectric actuator 100, the sheet piezoelectric actuator 200 and the optical fiber 300 constitute a scanner cantilever. The sheet piezoelectric actuator 200 and the coincident portion 500 make the inherent frequency of the scanner cantilever in the horizontal direction greater than the same order inherent frequency of the scanner cantilever in the vertical direction. The scanner cantilever in the vertical direction has a first order inherent frequency, a second order inherent frequency, a third order inherent frequency, …, and an Nth order inherent frequency. There is a certain order (for example, U order, U is an integer greater than or equal to two) of inherent frequency closest to the Vth order inherent frequency of the scanner cantilever in the horizontal direction (V is less than U). The closer the driving frequencies in two directions in the Lissajous scanning are, the closer the uniformity (density) of the scanning grid in the two directions is, and the more the number of points is. In theory, the closer the driving frequencies in the two directions are, the better. However, the closer the inherent frequencies of the scanner cantilever used in the two directions are, the more obvious the coupling effect is. Therefore, the application adjusts the shape structure and / or size parameters of the sheet piezoelectric actuator 200 and the coincident portion 500, so that the inherent frequencies of the scanner cantilever used in the two directions simultaneously meet the requirements of being close enough to ensure good scanning effect and having a uniform and dense scanning grid, and also meet the requirement of having a sufficient difference to prevent the vibration of the scanner cantilever in the two directions from being coupled.
[0027] Preferably, the natural frequency of the first piezoelectric actuator 100 in the left-right direction is the same as or similar to its natural frequency in the vertical direction. Here, the first piezoelectric actuator 100 refers to the first piezoelectric actuator 100 itself, excluding the sheet-shaped piezoelectric actuator 200 and other components such as optical fibers. The first piezoelectric actuator 100 meeting these requirements is a regularly shaped, rotationally symmetrical piezoelectric actuator, which is easy to manufacture, has easily controllable manufacturing errors, and a high yield rate. Examples include cylindrical piezoelectric actuators, square cylindrical piezoelectric actuators, round bar piezoelectric actuators, and square bar piezoelectric actuators. The sheet-shaped piezoelectric actuator 200 is also a conventional actuator, with low manufacturing difficulty. This application, by combining two easily manufactured components, obtains a scanner suitable for Lissajous scanning and with guaranteed anti-coupling effect, which is less difficult to manufacture and has a higher yield rate compared to existing Lissajous scanners.
[0028] Therefore, the difference satisfies that when the first piezoelectric actuator 100 performs Lissajous scanning under the drive signal, the scanner cantilever has sufficient amplitude so that the vibration of the scanner cantilever in the horizontal direction and in the vertical direction will not couple.
[0029] 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.
[0030] The optical fiber is fixedly mounted on the upper or lower surface of the sheet-like piezoelectric actuator 200, or disposed inside the sheet-like piezoelectric actuator 200, using a cantilever support method. The cantilever support refers to the portion of the optical fiber extending beyond the front end of the sheet-like piezoelectric actuator 200 forming an optical fiber cantilever, with the portion of the optical fiber located behind the cantilever fixedly connected to the sheet-like piezoelectric actuator 200. In one embodiment where the optical fiber is disposed inside the sheet-like piezoelectric actuator 200, the sheet-like piezoelectric actuator 200 body has a mounting hole for accommodating the optical fiber, and the optical fiber is fixedly mounted within the mounting hole using a cantilever support method.
[0031] As an example of the first piezoelectric actuator 100:
[0032] like Figure 3 As shown, the cylindrical actuator has a cylindrical body as a whole, with the axis of the body arranged in the front-to-back direction. The rear end of the body is fixedly connected to the base 400, and the front part of the body is connected to the rear end of the plate-shaped piezoelectric actuator 200.
[0033] The driving mode of the main body of the round tube type can be to attach a piezoelectric sheet, or the main body itself can be a piezoelectric material, and driving electrodes are arranged at corresponding positions of the inner surface and the outer surface. The structure of the round tube type actuator, and the structure of arranging a piezoelectric sheet or driving electrodes, etc. all belong to the conventional technical means in the field.
[0034] As shown in FIG. 1, the square tube type actuator has a square tube type main body in its entirety. The cross section of the square tube type can be a square profile, or a rectangular profile. The axis of the main body is arranged in the front-rear direction, the rear end of the tube type main body is fixedly connected with the base 400, and the front part of the tube type main body is connected with the rear end of the sheet type piezoelectric actuating part 200. Of course, preferably, when the cross section of the square tube type is a rectangular profile, the long side of the main body is arranged in parallel to the direction of the sheet type piezoelectric actuating part 200, so as to make the direction in which the sheet type piezoelectric actuating part 200 improves the natural frequency be the direction in which the main body itself has a higher natural frequency. Figure 4
[0035] The driving mode of the main body of the square tube type can be to attach a piezoelectric sheet, or the main body itself can be a piezoelectric material, and driving electrodes are arranged at corresponding positions of the inner surface and the outer surface. The structure of the square tube type actuator, and the structure of arranging a piezoelectric sheet or driving electrodes, etc. all belong to the conventional technical means in the field.
[0036] As shown in FIG. 1, the square tube type actuator has a square tube type main body in its entirety. The cross section of the square tube type can be a square profile, or a rectangular profile. The axis of the main body is arranged in the front-rear direction, the rear end of the tube type main body is fixedly connected with the base 400, and the front part of the tube type main body is connected with the rear end of the sheet type piezoelectric actuating part 200. Of course, preferably, when the cross section of the square tube type is a rectangular profile, the long side of the main body is arranged in parallel to the direction of the sheet type piezoelectric actuating part 200, so as to make the direction in which the sheet type piezoelectric actuating part 200 improves the natural frequency be the direction in which the main body itself has a higher natural frequency. Figure 5 The driving mode of the square rod type actuator can be to attach a piezoelectric sheet. The structure of the square rod type actuator, and the driving mode and driving structure thereof, etc. all belong to the conventional technical means in the field.
[0037] As shown in FIG. 1, the square tube type actuator has a square tube type main body in its entirety. The cross section of the square tube type can be a square profile, or a rectangular profile. The axis of the main body is arranged in the front-rear direction, the rear end of the tube type main body is fixedly connected with the base 400, and the front part of the tube type main body is connected with the rear end of the sheet type piezoelectric actuating part 200. Of course, preferably, when the cross section of the square tube type is a rectangular profile, the long side of the main body is arranged in parallel to the direction of the sheet type piezoelectric actuating part 200, so as to make the direction in which the sheet type piezoelectric actuating part 200 improves the natural frequency be the direction in which the main body itself has a higher natural frequency.
[0038] Figure 6 As shown in FIG. 1, the square tube type actuator has a square tube type main body in its entirety. The cross section of the square tube type can be a square profile, or a rectangular profile. The axis of the main body is arranged in the front-rear direction, the rear end of the tube type main body is fixedly connected with the base 400, and the front part of the tube type main body is connected with the rear end of the sheet type piezoelectric actuating part 200. Of course, preferably, when the cross section of the square tube type is a rectangular profile, the long side of the main body is arranged in parallel to the direction of the sheet type piezoelectric actuating part 200, so as to make the direction in which the sheet type piezoelectric actuating part 200 improves the natural frequency be the direction in which the main body itself has a higher natural frequency.
[0039] The driving mode of the round rod type actuator can be to attach a piezoelectric sheet. The structure of the round rod type actuator, and the driving mode and driving structure thereof, etc. all belong to the conventional technical means in the field.
[0040] Optionally, the sheet piezoelectric actuating part 200 is a single piezoelectric sheet actuator or a double piezoelectric sheet actuator.
[0041] It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that one skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word 'comprising' or 'including' does not exclude the presence of elements or steps other than those listed in a claim. The word 'a' or 'an' preceding an element does not exclude the presence of a plurality of such elements. The use of the word 'about' followed by a value and / or a range of values, indicates the value and / or range of values plus or minus 10% of the stated value and / or range of values.
[0042] All features disclosed in this specification, unless expressly stated to the contrary, are intended to be within the scope of the present application.
[0043] Any feature in the present specification that has recited dependencies, can apply to any other feature or claims in the specification with like dependencies. Any reference in this specification to 'one embodiment', 'an embodiment' etc. means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearance of the phrases 'in one embodiment' or 'in an embodiment' in various places in the specification are not necessarily all referring to the same embodiment.
[0044] The application is not restricted to the details of the foregoing specific embodiments. The application extends to any novel one, or any novel combination, of the features disclosed in this specification, and to any novel method or process disclosed or suggested in this specification, or any novel combination of steps of the methods or processes disclosed or suggested in this specification.
Claims
1. A Lissajous scanner characterized in that, The scanner cantilever is formed by the first piezoelectric actuating part, the sheet piezoelectric actuating part and the optical fiber.
2. A Lissajous scanner as claimed in claim 1, characterized in that The difference satisfies that the scanner cantilever has sufficient amplitude when the first piezoelectric actuating part makes Lissajous scanning under the driving of the driving signal, and makes the vibration of the scanner cantilever in the horizontal direction and in the vertical direction not coupled.
3. A Lissajous scanner as claimed in claim 1 or 2, characterized in that The natural frequency of the first piezoelectric actuating part in the left-right direction is the same as or similar to the natural frequency in the vertical direction.
4. A Lissajous scanner as claimed in claim 1 or 2, characterized in that The difference ranges from 10 Hz to 12 KHz.
5. A Lissajous scanner as claimed in claim 4, characterized in that The difference ranges from 1 KHz to 10 KHz.
6. A Lissajous scanner as claimed in claim 1 or 2, characterized in that The optical fiber is fixedly arranged on the upper surface or the lower surface of the support plate or in the interior of the support plate in a cantilever support mode.
7. A Lissajous scanner as claimed in claim 1 or 2, characterized in that The piezoelectric actuating part includes a round tube type piezoelectric actuator, a square tube type piezoelectric actuator, a square rod type piezoelectric actuator or a round rod type piezoelectric actuator.
8. A Lissajous scanner as claimed in claim 1 or 2, characterized in that The sheet piezoelectric actuating part is a single piezoelectric sheet actuator or a double piezoelectric sheet actuator.