Backlight Of TFT Research & LED Backlight Design L

Because the TFT-LCD panel can't emit the light by itself, in order to light the product it must have a backlight to add. While backlight is the key parts to optic constitutes for LCD display product. Along with the fast development of the IT industry, TFT-LCD industry keeps developing new items on the basis of their old ones. So as the core discreteness of the LCD product, backlight industry must certainly empolder the new product constantly with the new technology to catch the growing trend of the IT industry.The single backlight is not just a single accessory of the LCD product; it's a complex optical component consists of many kinds of accessories and materials. Since the design & development of backlight is a subject involving Optics, Physics, Materials, Electrics and other subjects, the better performance of backlight should be derived from researches in different aspects: such as material design, optic analysis, mould development, performance testing and circuits driving.In the first part of this dissertation, the author introduces the development history of the LCD backlight. Then the author gives a brief introduction of the principle of backlight and its application in the TFT-LCD and make a forecast for the backlight market at present and its' development in the future. In this section of the introduction of the backlight research, the author makes a detail introduction of the design strategy for backlight and takes a deeper study in CCFL backlight-the most popular backlight at present. Based on the fundamental material of its component, the author makes an explanation in detail about CCFL backlight from its principle and structure. Then the author gives us an example on how the CCFL backlight is designed, which shows the complete developing procedure of new products, and illustrate the problems and related resolvent during the whole procedure from the development stage to design stage of new products.In the second section of the dissertation, the author gives a general introduction of the fundamental knowledge of newly LED backlight, such as the development history of LED products, the technology advantage of LED, comparing to the CCFL backlight products above. Then the author makes an introduction of the LED driving circuit, and explains the controlling method of LCD, LED backlight referring to the actual examples. In the end, aiming to problems that LED faced at present, new development strategies are raised at the same time.In the last section of the dissertation, the author makes a brief introduction of the latest LED design. In the very beginning, a single white LED backlight design procedure has been taken as an instance; the author makes a specific explanation to the design procedure of this new backlight from many aspects such as the carry out of project plan, the design and simulation of LED backlight, the design of circuit control of LED backlight. In the end, the author makes an introduction of the latest RGB backlight of three mixed colors on the basis of the relating testing data.