Study on Optical Servosystem

1.光伏效应的机理为了阐明PLZT元件中光伏效应的机理，提出了PLZT元件中光伏效应的电学模型，该模型由依赖于光强的电流源、依赖于光强和元件温度的电阻和依赖于温度的电容并联而成。2. PLZT元件特性的改善从电模型可以看出，PLZT元件具有很慢的二阶响应速度。通过在PLZT元件的表面上照射用于加热的光而引起的热电效应的叠加，可以显著改善响应速度的上升时间，并且通过控制用于加热的光的照射时间，也改善了响应的稳定时间。实验表明，掺杂0.5mol%的W， ...更多信息 研究了双压电晶片型光致动器的位移控制方法，并对双压电晶片型光致动器的位移控制方法进行了研究。在简单的开-关控制中，在阶跃响应中引起一些大的稳态振荡，因为系统中控制照射时间所需的光学快门具有严重的时滞特性。研究了另外两种方法来补偿这一弱点。一种是通过控制驱动器的当前位移、当前速度以及与它们相关的阈值来控制辐照时间的方法。另一种是预测控制，其中通过考虑光闸的当前位移和时间滞后来预测照射时间。实验结果表明，预测控制在这三种控制方法中是最适用的，可以说，如果对PLZT元件的光学驱动器作进一步的研究，它是适用于光学伺服系统的。少

1.Mechanism of Photovoltaic Effect.The electric model for the photovoltaic effect in PLZT element is proposed to make clear the mechanism of the photovoltaic effect in it. The model is constructed in parallel by an electric current source dependent on the light intensity, electric resistance on the light intensity and the temperature of the element, and the electric capacitance on the temperature. The validity of this model is shown by the experiment.2.Inprovement of Characteristics of PLZT Element.It can be estimated from the electric model that the PLZT element has the very slow response speed of second ordor. The rise time of the response speed can be considerably improved by the superposition of the pyro-electric effect caused by irradiating the light for heating on the surface of the PLZT element, and the settling time of the response is also improved by controlling the time to irradiate the light for heating. It is clarified by the experiment that the doping of W of 0.5 mol% impr … More oves the response speed, and the optimization of the doping should be investigated for the improvement.3.Development of Control Method in Optical Servosystem.Some control methods of the displacement of the bimorph type optical actuator are developed. In a simple On-Off control some large stationary oscillation is caused in the step response because the optical shutter in the system necessary for control of the irradiating time has severe time lag characteristic. The other two methods are studied to compensate the weak point. The one is the method where the irradiating time is controled by considering the current displacement of the actuator, the current velocity and a threshold relating to them. The other is a predicition control where the irradiating time is predicted by cunsidering the current displacement and the time lag of the optical shutter. It is clarified by the experiment that the prediction control is most applicable among these three methods.It can be said from these results that the optical actuator using PLZT element is applicable to the optical servosystem if they will be investigated further in detail. Less