Research And Implementation Of Time-Space Mix-Modulation And Scan-Drive Model For TFT-LCD

This thesis embarks from the traditional TFT-LCD scan-drive technology and the visual characteristics and imaging principle of human body eye, discussed in the insufficiency of the traditional TFT-LCD scan-drive actuation which caused the difficulty of upgrading image display gray-scale level. Then, this paper proposes a novel framework named as time-space mix-modulation scan-drive framework and set up the corresponding mathematical model. In order to achieve maximum scan-drive efficiency, this paper uses genetic algorithm to achieve the most efficient scanning sequence, with which the display system can reduce the demand on hardware resources. By using FPGA implementation, we verified the time-space mix-modulation scan-drive framework, eventually completed the IP core design. The main work and achievements are as follows:1. This thesis explores the whole process of the traditional gray-scale TFT-LCD image display, and analyzes the impact of the human eye imaging principle and the human visual characteristics on the image display. With the depth analysis of the traditional TFT-LCD scan-drive process, this paper set up the mathematical model of the traditional scan-drive framework, pointing out the redundancy questions in the traditional framework. This paper built the Time-space mix-modulation scan-drive framework with proposing Time-space mixed-scanning strategy and deduced the corresponding mathematical model. This framework includes the time-domain frame modulation technique and the spatial domain digital-analog converter (DAC) gray-scale modulation. The time-domain frame modulation technique completed the digital image high-level gray-scale scan-drive, including multi-screen subspace scanning frame modulation and the self-coupling frame dithering algorithm. The spatial domain modulation completed the digital image low-level gray-scale scan-drive by using the digital-to-analog converter modulation in the source IC of TFT-LCD. Time-space mix-modulation scan-drive framework can effectively enhance the gray-scale display level of TFT-LCD.2. The first time the genetic algorithm is applied to TFT-LCD scan-drive process. This author uses genetic algorithm to optimize the mathematical model of multi-screen subspace scanning frame modulation, in order to seek the most efficient scanning sequence of the different gray-scale scan-drive case. With these scanning sequences, the maximum scan-drive efficiency of time-space mix-modulation scan-drive framework can be achieved, while the system demand for hardware resources can be reduced, and the reliability of the display system implementation can be improved.3. This thesis proposed a new dithering algorithm named as self-coupling frame dithering algorithm by optimizing the traditional dithering algorithm and combining with frame modulation technology. This new algorithm can enhance TFT-LCD display gray-scale level and the color gentle degree, while does not reduce the image resolution ratio.4. According to the features of time-space mix-modulation scan-drive framework, this paper put forward a mixed gamma-correction techniques, including time-domain modulation figure on the Non-linear correction and space domain on non-linear digital-analog conversion correction. We obtained the different parameters of the gamma correction datum was, by simulating the LCD Physical properties. The image of the gamma correction was realized by the use of table manner.5. The time-space mix-modulation scan-drive IP core was designed, which realized the engineering application of the novel time-space mix-modulation scan-drive framework. FPGA verification platform was constructed in the 17-inch 1280 * 1024 dot-matrix color TFT-LCD display, with which we have carried out realization and verification on to the novel scan-drive model. The real-time configuration interface was designed in the IP core, with which the gray-scale level parameters and contrast adjustment parameters setting functions can be realized. Then we can upgrade different TFT-LCD display platforms and make up the defect caused by the scaler. With all of these, the foundation for engineering applications of time-space mix-modulation scan-drive was established.