【作者】 张雅；

【导师】 蔡长龙；

【作者基本信息】 西安工业大学 ， 光学工程， 2012， 硕士

【摘要】 红外热成像探测器由于其应用广泛而备受关注,而非制冷型探测器与制冷型探测器相比,具有体积小、成本低和可靠性高的优势。近些年来,随着红外探测成像技术的发展,现有的非制冷探测技术遇上了技术瓶颈,其中关键是缺乏高性能材料。克服这一困难的技术途径很多,如采用全新的信号产生和读出机制、寻找不同于常规的新材料等。本文基于胆甾相液晶热光效应,设计了一种新型光学读出方式的红外探测成像系统,其核心部件为红外敏感装置,由装在红外液晶盒内的胆甾相液晶构成。以此光学系统为平台,本文重点研究了胆甾相液晶的旋光特性、红外液晶盒中红外吸收薄膜与取向薄膜的制备工艺。在胆甾相液晶旋光特性的研究方面,通过设计搭建测量光路,研究了温度变化速率、S811的含量、测量光路中起偏器与检偏器夹角θ对胆甾相液晶旋光特性的影响,并制备出了旋光特性符合本文成像要求的胆甾相液晶样品。在红外吸收薄膜制备过程中,选取ITO为红外吸收材料,采用磁控溅射法沉积薄膜,研究了制备工艺参数对薄膜厚度、光学特性及方阻特性的影响,获得了红外吸收率为58%的ITO薄膜的最佳制备工艺参数。在取向薄膜制备过程中,选取聚酰亚胺(PI)为取向材料,重点研究了PI浓度、匀胶转速、热处理时间与温度对取向薄膜厚度的影响,制备出了固化后膜厚为63nm的取向薄膜,并对其光学特性进行了研究。通过对本课题的研究,设计出了一种实现光学读出红外探测成像的新方法,本光学读出系统具有无需制冷,无需金属导线连接,在探测器上不会产生附加热量等优点,这为液晶材料的应用与光学读出方式的红外探测成像技术提供了新的研究思路。更多还原

【Abstract】 Much attention has been paid to thermal irradiation detectors for their wide applications. Compared with cooled detectors, uncooled thermal imaging devices have many advantages, such as small dimension, low cost, and superior reliability. In recent years, with the infrared detect imaging technology rapidly developing, uncooled detection technology meets the technical bottlenecks, and the key problem is lacking of high-performance materials. There are many ways to solve this problem, such as using the new way for the signal generation and reading, or looking for new materials.Based on the optical rotation property of cholesteric liquid crystals(CLCs), an optical readout infrared detect imaging system is designed. The core of the system is the infrared sensitive device composed of the infrared liquid crystal box and CLCs. In this article, the optical rotation characteristic of CLCs with temperature changing, the production process of infrared absorption thin film, and orientation thin film in the infrared liquid crystal box are studied. In order to study the optical rotation characteristic of CLCs, a measuring optical path is designed. The impact of the rate of temperature change, S811 content, and the angle between the two polarizers on the optical rotation is studied, and the samples of CLCs that meet the imaging requirements are produced. In the production process of infrared liquid crystal box, the ITO prepared by RF magnetron sputtering is selected as the infrared absorption material. The impact of the process parameters on the thickness, optical properties and electrical properties of ITO thin film are also researched. The optimal technological parameters are obtained for ITO thin film with the infrared absorption of 58%. On the other hand, the orientation material is polyimide. Our study focuses are the impacts of the concentration of polyimide solution, the speed of spinning coater, temperature and time of thermal processing on the thickness of the orientation thin film. With a lot of experiments, the samples of PI thin film are obtained that the thickness is 63nm after curing, and the optical properties of the samples are also analyzed.In this subject, a new method for optical readout infrared detection imaging is achieved. This optical readout system does not need the cooling device and metal wires, and it does not produce additional heat on the detector, so it provides a new idea for the application of liquid crystal material and the optical readout infrared detection imaging technology.更多还原