Piezoelectrically driven microelectromechanical scanning mirror for optical coherence tomography probes

Abstract

The utility model discloses a piezoelectric drive micro electro mechanical scanning mirror for optical coherence tomography probe, piezoelectric drive micro electro mechanical scanning mirror for optical coherence tomography probe includes: base, lens, a plurality of piezoelectric driver, piezoelectric driver at least includes first electrode layer, second electrode layer and piezoelectric layer, piezoelectric layer is located between two first electrode layer and second electrode layer, piezoelectric layer is lead zirconate titanate piezoelectric film, piezoelectric driver links to each other with base, a plurality of elastic beams, every piezoelectric driver links to each other with the lens through elastic beam. Piezoelectric drive micro electro mechanical scanning mirror for optical coherence tomography probe according to the utility model embodiment has the advantages such as small demand voltage, high scanning frequency, small volume.

Description

Technical Field

[0001] This utility model relates to the field of optical imaging technology, and more specifically, to a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography probe. Background Technology

[0002] The driving methods for scanning mirrors in related technologies include electrostatic, electrothermal, and electromagnetic driving methods. For the in vivo application of optical coherence tomography (OCT) probes: electrostatically driven scanning mirrors usually require high voltage driving, making them difficult to use in the human body; the response speed of electrothermally driven scanning mirrors is determined by the material's sensitivity to temperature, resulting in a slow response speed and low scanning frequency; electromagnetically driven scanning mirrors require the electromagnet to be integrated into the scanning mirror, resulting in a large size that cannot achieve small-size probe packaging. Utility Model Content

[0003] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography (OCT) probe, which has advantages such as low voltage requirement, high scanning frequency, and small size.

[0004] To achieve the above objectives, an embodiment of this utility model proposes a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography (OCT) probe. The piezoelectric-driven OCT probe includes: a base; a lens; multiple piezoelectric actuators, each of which includes at least a first electrode layer, a second electrode layer, and a piezoelectric layer, the piezoelectric layer being located between two of the first electrode layers and the second electrode layer, the piezoelectric layer being a lead zirconate titanate piezoelectric film; the piezoelectric actuators being connected to the base; and multiple elastic beams, each of the piezoelectric actuators being connected to the lens via the elastic beams.

[0005] The piezoelectric-driven microelectromechanical scanning mirror for optical coherence tomography probe according to the present invention has the advantages of low voltage requirement, high scanning frequency, and small size.

[0006] In addition, the piezoelectrically driven microelectromechanical scanning mirror for optical coherence tomography probe according to the above embodiments of the present invention may also have the following additional technical features: According to one embodiment of the present invention, the elastic beam has a sinusoidal wave shape in a cross section perpendicular to the axial direction of the lens.

[0007] According to one embodiment of the present invention, the piezoelectric actuator is located radially outward of the lens, and a plurality of the piezoelectric actuators are arranged at circumferential intervals along the lens.

[0008] According to one embodiment of the present invention, there are four piezoelectric actuators, and each pair of adjacent piezoelectric actuators are arranged symmetrically.

[0009] According to one embodiment of the present invention, each of the piezoelectric actuators extends circumferentially along the lens, one end of each piezoelectric actuator is connected to the base and the other end is connected to the lens via the elastic beam.

[0010] According to one embodiment of the present invention, the first electrode layer and the second electrode layer are respectively a copper electrode layer and a platinum electrode layer.

[0011] According to one embodiment of the present invention, the piezoelectric-driven microelectromechanical scanning mirror for optical coherence tomography probe further includes a substrate layer, the first electrode layer is connected to the piezoelectric layer through a first adhesion layer, and the second electrode layer is connected to the substrate layer through a second adhesion layer.

[0012] According to one embodiment of the present invention, the first adhesive layer and the second adhesive layer are titanium layers.

[0013] According to one embodiment of the present invention, the piezoelectric-driven microelectromechanical scanning mirror for optical coherence tomography probe further includes electrode leads, the electrode leads including a first electrode lead layer, a second electrode lead layer and an insulating layer, the first electrode lead layer being connected to the first electrode layer, the second electrode lead layer being connected to the second electrode layer, and the insulating layer being disposed between the first electrode lead layer and the second electrode lead layer.

[0014] According to one embodiment of the present invention, the insulating layer includes an aluminum oxide layer and a silicon oxide layer.

[0015] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the structure of a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography probe according to an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the structure of a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography probe according to an embodiment of the present invention.

[0018] Figure 3This is a cross-sectional view of a piezoelectric actuator for a piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to an embodiment of the present invention.

[0019] Figure 4 This is a cross-sectional view of the electrode leads of a piezoelectric-driven microelectromechanical scanning mirror for an optical coherence tomography probe according to an embodiment of the present invention.

[0020] Reference numerals: piezoelectric-driven microelectromechanical scanning mirror 1, lens 10, piezoelectric actuator 20, first electrode layer 21, second electrode layer 22, piezoelectric layer 23, substrate layer 24, first adhesive layer 25, second adhesive layer 26, elastic beam 30, electrode lead 40, first electrode lead layer 41, second electrode lead layer 42, insulating layer 43, alumina layer 431, silicon oxide layer 432, lead substrate layer 44, first lead adhesive layer 45, second lead adhesive layer 46 for optical coherence tomography probe. Detailed Implementation

[0021] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0022] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0023] The piezoelectrically driven microelectromechanical scanning mirror 1 for an optical coherence tomography probe according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0024] like Figures 1-4 As shown, the piezoelectric-driven microelectromechanical scanning mirror 1 for an optical coherence tomography probe according to an embodiment of the present invention includes a base (not shown in the figure), a lens 10, a plurality of piezoelectric actuators 20 and a plurality of elastic beams 30.

[0025] Each piezoelectric actuator 20 includes at least a first electrode layer 21, a second electrode layer 22, and a piezoelectric layer 23. The piezoelectric layer 23 is located between the two first electrode layers 21 and the second electrode layer 22. The piezoelectric layer 23 is a lead zirconate titanate (PZT) piezoelectric film. The piezoelectric actuator 20 is connected to the base. Each piezoelectric actuator 20 is connected to the lens 10 via an elastic beam 30.

[0026] Specifically, the lens 10 uses an electron beam evaporation process to deposit a nanoscale gold film to increase the reflection efficiency of incident light.

[0027] The lead zirconate titanate piezoelectric thin film is a magnetron sputtered lead zirconate titanate piezoelectric thin film.

[0028] When a voltage is applied to the first electrode layer 21 and the second electrode layer 22 of the piezoelectric actuator 20, the piezoelectric layer 23 will undergo electrostatic contraction due to the reverse voltage effect, thereby causing the piezoelectric actuator 20 to undergo mechanical deformation. The deformation generated by the piezoelectric actuator 20 is transmitted to the lens 10 through the elastic beam 30, causing the lens 10 to be displaced and deflected.

[0029] According to an embodiment of the present invention, a piezoelectric-driven microelectromechanical scanning mirror 1 for an optical coherence tomography (OCT) probe is provided with a piezoelectric actuator 20, which includes at least a first electrode layer 21, a second electrode layer 22, and a piezoelectric layer 23. The piezoelectric layer 23 is a lead zirconate titanate piezoelectric film. By applying voltage to the electrode layer, the piezoelectric layer 23 can undergo electrostatic contraction, thereby causing mechanical deformation of the piezoelectric actuator 20 and driving the lens 10 to produce displacement and deflection. Compared with the electrostatic driving method used in related technologies, the piezoelectric actuator 20 requires a smaller voltage and can be driven at a low voltage, enabling its application in the human body. Compared with the electrothermal driving method used in related technologies, the piezoelectric actuator 20 has higher sensitivity, which can improve the response speed of the lens 10 and increase the scanning frequency. Compared with the electromagnetic driving method used in related technologies, the lead zirconate titanate piezoelectric film occupies a smaller volume, which can facilitate the reduction of the size of the piezoelectric-driven microelectromechanical scanning mirror 1 for an OCT probe and realize the small-size packaging of the OCT probe.

[0030] Therefore, the piezoelectric-driven microelectromechanical scanning mirror 1 for optical coherence tomography probe according to the present invention has advantages such as low voltage requirement, high scanning frequency, and small size.

[0031] The piezoelectrically driven microelectromechanical scanning mirror 1 for an optical coherence tomography probe according to a specific embodiment of the present invention is described below with reference to the accompanying drawings.

[0032] In some specific embodiments of this utility model, such as Figures 1-4 As shown, the piezoelectric-driven microelectromechanical scanning mirror 1 for an optical coherence tomography probe according to an embodiment of the present invention includes a base, a lens 10, a plurality of piezoelectric actuators 20 and a plurality of elastic beams 30.

[0033] Advantageously, such as Figure 1 and Figure 2 As shown, the elastic beam 30 has a sinusoidal wavy shape in the cross-section perpendicular to the axis of the lens 10. This can improve the transmission efficiency of the driving force between the piezoelectric actuator 20 and the lens 10, and increase the deflection angle of the lens 10.

[0034] Specifically, such as Figure 1 and Figure 2 As shown, the piezoelectric actuators 20 are located radially outside the lens 10, and multiple piezoelectric actuators 20 are arranged at intervals along the circumference of the lens 10. This facilitates the piezoelectric actuators 20 in driving the lens 10 and avoids interference with the movement of the lens 10.

[0035] More specifically, such as Figure 1 and Figure 2As shown, there are four piezoelectric actuators 20, and each pair of adjacent piezoelectric actuators 2020 is arranged symmetrically. This facilitates the deflection drive of the lens 10 in different directions, enabling dual-axis Lissajous scanning for two-dimensional scanning, and combined with three-dimensional scanning imaging algorithms to achieve high-precision imaging.

[0036] Specifically, such as Figure 2 As shown, the four piezoelectric actuators 20 are labeled a, b, c, and d in a clockwise direction. For example, each piezoelectric actuator 20 has a first resonant frequency and a second resonant frequency. When driving the lens 10, the first resonant frequency is applied to piezoelectric actuators a and b, driving the lens 10 to deflect along the first axis; the first resonant frequency is applied to piezoelectric actuators c and d, driving the lens 10 to deflect along the second axis; thus, the lens 10 is deflected along the first and second axes, i.e., the lens 10 is deflected in two dimensions.

[0037] When a driving voltage is applied, a voltage of 0V is applied to the second electrode layer 22 of the piezoelectric actuator 20, and a voltage greater than 0V is applied to the first electrode layer 21 of the piezoelectric actuator 20. The applied voltage signal is a sinusoidal signal. By designing the frequency and phase of the sinusoidal signal, the scanning trajectory can be changed to achieve high-resolution scanning imaging and meet the imaging requirements of optical coherence tomography probes.

[0038] Furthermore, such as Figure 1 and Figure 2 As shown, each piezoelectric actuator 20 extends circumferentially along the lens 10, with one end of each piezoelectric actuator 20 connected to the base and the other end connected to the lens 10 via an elastic beam 30. This facilitates the deformation of the piezoelectric actuator 20 onto the lens 10, causing the lens 10 to deflect.

[0039] Figure 3 and Figure 4 A piezoelectrically driven microelectromechanical scanning mirror 1 for an optical coherence tomography probe is shown, according to some examples of the present invention. For example... Figure 3 As shown, the first electrode layer 21 and the second electrode layer 22 are copper electrode layers and platinum electrode layers, respectively. This improves the conductivity of the electrode layers.

[0040] Specifically, such as Figure 3 and Figure 4 As shown, the piezoelectric-driven microelectromechanical scanning mirror 1 used for optical coherence tomography (OCT) probes also includes a substrate layer 24. A first electrode layer 21 is connected to a piezoelectric layer 23 via a first adhesive layer 25, and a second electrode layer 22 is connected to the substrate layer 24 via a second adhesive layer 26. This facilitates adhesion between the electrode layer, the substrate layer 24, and the piezoelectric layer 23.

[0041] Optionally, the first adhesive layer 25 and the second adhesive layer 26 are titanium layers. This can improve the adhesion effect.

[0042] More specifically, such as Figure 4 As shown, the piezoelectric-driven microelectromechanical scanning mirror 1 used for optical coherence tomography (OCT) probes also includes electrode leads 40. The electrode leads 40 include a first electrode lead layer 41, a second electrode lead layer 42, and an insulating layer 43. The first electrode lead layer 41 is connected to the first electrode layer 21, and the second electrode lead layer 42 is connected to the second electrode layer 22. The insulating layer 43 is disposed between the first electrode lead layer 41 and the second electrode lead layer 42. Specifically, the first electrode lead layer 41 is a copper layer and the second electrode lead layer 42 is a titanium layer. This facilitates ensuring the insulation between the first electrode lead layer 41 and the second electrode lead layer 42, improving the reliability of applying voltage to the electrode layers.

[0043] Optionally, such as Figure 4 As shown, the insulating layer 43 includes an aluminum oxide layer 431 and a silicon oxide layer 432. This can further improve the insulating performance of the insulating layer 43.

[0044] Specifically, the electrode lead 40 also includes a lead substrate layer 44. The first electrode lead layer 41 is connected to the insulating layer through a first lead adhesion layer 45, and the lead substrate layer 44 is connected to the second electrode lead layer 42 through a second lead adhesion layer 46. Both the first lead adhesion layer 45 and the second lead adhesion layer 46 are titanium layers. The first lead adhesion layer 45 is connected to the aluminum oxide layer 431, and the second electrode lead layer 42 is connected to the silicon oxide layer 432. This facilitates the adhesion between the electrode lead layer, the lead substrate layer 44, and the insulating layer 43.

[0045] Other configurations and operations of the piezoelectrically driven microelectromechanical scanning mirror 1 for optical coherence tomography probe according to the embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0047] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe, characterized in that, include: Base; lens; Multiple piezoelectric actuators, each piezoelectric actuator including at least a first electrode layer, a second electrode layer and a piezoelectric layer, the piezoelectric layer being located between two first electrode layers and two second electrode layers, the piezoelectric layer being a lead zirconate titanate piezoelectric film, the piezoelectric actuator being connected to the base; Multiple elastic beams, each of the piezoelectric actuators being connected to the lens via the elastic beam.

2. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, The elastic beam has a sinusoidal wavy shape in a cross section perpendicular to the axis of the lens.

3. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, The piezoelectric actuator is located radially outside the lens, and a plurality of the piezoelectric actuators are arranged at circumferential intervals along the lens.

4. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, The piezoelectric actuators are four in number and are arranged symmetrically between any two adjacent piezoelectric actuators.

5. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, Each of the piezoelectric actuators extends circumferentially along the lens, with one end of each piezoelectric actuator connected to the base and the other end connected to the lens via the elastic beam.

6. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, The first electrode layer and the second electrode layer are a copper electrode layer and a platinum electrode layer, respectively.

7. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, It also includes a substrate layer, wherein the first electrode layer is connected to the piezoelectric layer through a first adhesive layer, and the second electrode layer is connected to the substrate layer through a second adhesive layer.

8. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 7, characterized in that, The first adhesive layer and the second adhesive layer are titanium layers.

9. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 1, characterized in that, It also includes electrode leads, which include a first electrode lead layer, a second electrode lead layer and an insulating layer. The first electrode lead layer is connected to the first electrode layer, the second electrode lead layer is connected to the second electrode layer, and the insulating layer is disposed between the first electrode lead layer and the second electrode lead layer.

10. The piezoelectrically driven microelectromechanical scanning mirror for an optical coherence tomography probe according to claim 9, characterized in that, The insulating layer comprises an aluminum oxide layer and a silicon oxide layer.

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