Development of High Precision Fast Light Deflectors Utilizing Inverted Domains of Lithium Niobate Single Crystals.

本研究项目的目的是利用LiNbO_3的倒磁区，提出由单晶片组成的无粘结层的光偏转器，并研制响应快、扫描范围宽的紧凑型高精度光偏转器。1.得到了如下结果：1.对于具有倒向域层的板，最适合于有效地产生扭转运动而不引起弯曲运动的最优切割是148ﾟ旋转Y形切割板，其较长的一侧相对于Z‘轴倾斜52ﾟ。2.在-100~150ﾟ的温度范围内，测量了LiNbO_3的横向压电应变常数和耦合系数随温度的变化关系，结果表明，LiNbO_3的横向压电常数和耦合系数随温度变化较小。3.从理论上分析了扭转驱动器的静态变形和共振特性，给出了获得宽扫描范围和快速响应…的设计准则更多的是既定的。4.研究了形成倒磁层的热处理条件、光偏转器的支撑方法、电击穿对策和减振方法，建立了光偏转器的制造工艺。5.实验表明，用140ﾟ旋转Y切LiNbO_3片制作的光偏转器具有良好的线性度和无滞后。通过施加()Sy的电压，获得了高达25ﾟ的光扫描范围。-.])1.5千伏至尺寸为17*5*0.1 mm^3.6的光偏转器。当以谐振频率驱动7.5x3x0.1mm3的小尺寸偏转器时，在16V&lt；p-p&gt；7的低交流电压下，获得了20ﾟ的较大扫描范围。提出了一种用于波分复用光通信系统的由光偏转器和法布里-珀罗标准具组成的可调谐滤光器，并证明了该滤光器具有窄带(0.15 nm)可调特性。较少

The purpose of this research project is to propose light deflectors consisting of a single crystal plate with no bonding layr by utilizing inverted domains of LiNbO_3 and to develop comact high precision light deflectors with a quick response and a wide scanning range. The results obtained in this project are summarized as follows : 1. The optimal cut suitable for generating only torsional motion efficiently without causing bending motion in a plate with an inverted domain layr was found to be the 148ﾟ rotated Y-cut plate with the longer side tilted 52ﾟ from the Z' axis. 2. The temperature dependences of the transverse piezoelectric strain constant and coupling factor of LiNbO_3 were measured in the range from-100ﾟto+150ﾟC and were shown to be considerably small compared to those of piezoelectric ceramics 3. The static deformation and resonant vibration of the torsional actuator were theoretically analyzed and the design guideline for attaining wide scannning range and quick response w … More as established. 4. The heat treatment conditions for forming an inverted domain layr, methods for supporting light deflectors, countermeasures for electrical breakdown, and vibration damping methods were examined and the fabrication process of light deflectors was established. 5. It was experimentally shown that a light deflector fabricated using a 140ﾟ rotated Y-cut LiNbO_3 plate had an excellent linearity and no hysteresis. A light scanning range as large as 25ﾟ was attained by application of a voltage of (]SY.+-.])1.5 kV to a light deflector with dimensions of 17*5*0.1 mm^3.6. When a small-size deflector with dimensions of 7.5*3*0.1 mm^3 was driven at the resonant frequency, a larger scanning range of 20ﾟ was attained with a low ac voltage of 16 V_<p-p>.7. A tunable optical filter consisting of the light deflector and a Fabry-Perot etalon was proposed for wavelength division multiplexed optical communication systems and was demonstrated to have narrowband (0.15nm) tunable characteristics. Less