A New Type Of Orthogonal Gradient Index Micro-cylinder Lens Arrays Used For LD Beam Shaping

The first semiconductor laser in the world was born in the early sixties of 20th century, after nearly half a century of development, the performance and technology of semiconductor lasers have been greatly improved. As a member of semiconductor lasers, laser diode(LD) has a small size, light weight, and high power conversion efficiency. Tuning and modulation could be achieved by changing temperature, doping, magnetic field, and stress. The range of applications is very wide because of the long life, low cost, easy mass production, etc. For example, LD could be used widely in optical fiber communications, medical equipment, optical storage and laser printing, solid-state laser pump, aerospace, military and other fields of science and technology.However, the spot shape of laser diode spot is elliptical, which brings a lot of inconveniences to the application, it is necessary to use beam shaping to improve its beam quality. Therefore, the laser diode beam shaping technology has been a popular research topic which accompanied the development of semiconductor lasers. At the same time, various shaping devices were designed such as aspherical lens, self-focusing lens, binary optics, isosceles right-angle prism and micro-prism stack. Certain effects can be achieved by these devices on beam quality controlling, but still can not meet people's requirements.In this thesis, I summed up and analyzed the shaping methods and devices which appeared in recent years, compared their respective advantages and disadvantages. On this basis, I proposed a new type of orthogonal gradient index micro-cylinder lens arrays for LD beam shaping, and studied the shaping theory and imaging properties in-depth. Some samples which coincided with the theoretical design have been produced.The thesis includes six parts. The first chapter introduces the development and application of LD and the meaning of beam shaping,then analyses the current commonly used method of beam shaping, and put forward a new idea of orthogonal gradient index micro-cylinder lens. The second part of the thesis describes the ion-exchange theory. The imaging properties of orthogonal gradient index micro-cylinder lens are contained in the third chapter. The two following chapters discuss the production process and test the performance of the lens. In addition, the conclusion and outlook are made in the final chapter.