Piezoelectric thick diaphragm driving micro deformable mirror and producing method thereof

Abstract

The invention belongs to a microdeformable mirror and the machining and preparing field thereof, concretely relating to a piezoelectric film drive-based microdeformable mirror and the preparing method thereof. And the mcirodeformable mirror comprises micro actuator array composed of actuating units and mirror surface, where the micro actuator array is of a centrosymmetric regular hexagonal structure and the mirror composed of monocrystalline silicon diaphragm is connected with upper electrodes through photosensitive high polymer boss; the preparing course comprises: preparing silicon substrate piezoelectric ceramic base film, using wet-etching process to etch the silicon substrate piezoelectric ceramic base film, using wet-etching process to etch silicon substrate piezoelectric ceramic thick film shape, preparing upper electrode array on the silicon substrate piezoelectric ceramic thick film array, and preparing connection boss on the upper surface of the upper electrode array and using photosensitive high polymer to fix the mirror surface on the actuator array. And the microdeformable mirror can drive the mirror to generate larger displacement so as to meet the requirements of the fields of astro-observation, amotio imaging, etc; and the preparing method has simple process, low cost and good commercial application prospect.

Description

Technical field: [0001] The invention belongs to the field of micro-deformable mirrors and their processing and preparation, and in particular relates to a micro-deformable mirror driven by a piezoelectric film and a preparation method thereof. Background technique: [0002] Deformable mirror is a new type of optical device that can be used in optical systems for optical path wavefront distortion correction, photoelectric identification of friend and foe, etc. It has good application prospects in both military and civilian markets. For example, when the deformable mirror is used for human retinal imaging, it can correct the aberrations of living human eyes that change randomly in time and space, so as to obtain high-resolution visual cell images close to the diffraction limit, so as to achieve the goal of seriously affecting human vision and vision. Early diagnosis of blinding diseases (such as retinal vascular disease, macular disease, retinal detachment and other fundus di...

AI Technical Summary

Problems solved by technology

This kind of deformable mirror uses piezoelectric film actuator array to drive the mirror surface deformation, which avoids the defect of high working voltage of electrostatically driven deformable mirror, but because its piezoelectric film is prepared by gel-gel method, its preparation process Complexity, poor stability and repeatability, commercial application is very difficult, and the driving force of the piezoelectric film is weak, resulting in a small effective displacement of the mirror (generally no more than 2 microns), which cannot meet the needs of special users, such as for Micromechanical deformable mirrors in the fields of astronomical observation and retinal imaging usually require their effective deformation to be 5-10 microns, or even higher

Moreover, although the mirror surface is made of SOI silicon wafers, which overcomes the shortcomings of the large initial deformation of the mirror surface in the electrostatically driven deformable mirror, the price of SOI silicon wafers is high, and the corresponding processing equipment requirements are high, so the cost of preparing such mirrors is high.

At the same time, the mirror surface and the actuator array in this type of deformable mirror are fixed by metal bosses, and the fixing operation of the two usually needs to be carried out under high vacuum, which requires high equipment

In addition, since the adjacent piezoelectric film actuator units form a regular quadrilateral structure, the decoupling algorithm for controlling the mirror shape is more complicated, which is not conducive to the decoupling control and optimal control of the mirror shape.

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