Research On Flexible Electronic Paper Display Devices Based On PDLC Materials

As a new type of display technology,flexible electronic paper display technology,with its small size,light weight,low power consumption,passive light emission and other characteristics,has become one of the most important directions in the research of modern display technology.Most of the existing flexible display devices are based on OLED technology.Because the flexibility is limited by the characteristics of the substrate material,it can't achieve true flexibility.As a display material,PDLC(polymer dispersed liquid crystal)has the characteristics of high contrast,faster response time,passive luminescence display,and easy to make flexible panels.It has many inherent advantages in the field of flexible electronic paper display technology.In this paper,a flexible display device for passive luminescence is studied by using PDLC as the display material.In this paper,the basic display principle and physical structure of PDLC display film are described first,and then the principle of color control of PDLC display film is analyzed,namely saturation control.Through the related research of color science,the method of color calculation and measurement for full-color display of PDLC electronic paper is given.After that,the PDLC film produced by a manufacturer in Beijing was used as a sample.The basic photoelectric characteristics of PDLC film materials were investigated.After completing the measurement of the basic photoelectric properties of PDLC thin film samples,the basic structure of the pixel of the display device was designed.In the structure of color display,based on the analysis of the principle of color perception of human eyes and the principle of color mixing,RGB is adopted as the three-base color of subpixel.Then,based on the basic pixel structure,the arrangement of two pixel arrays of hashing and matrix is presented,and their advantages and disadvantages are analyzed and compared.For the drive of PDLC display device,this paper proposes two schemes:multi gray level analog voltage drive and time division control waveform drive.After the analysis of the two schemes,the scheme of driving the time division waveform is determined.The multistage gray scale control of PDLC can be realized by the way of waveform superposition,which produces different voltage waveforms of the duty ratio.According to the pixel structure of matrix type,the circuit structure of TFT substrate in electrophoretic electronic paper display is analyzed.The driving scheme of matrix PDLC material is tested by electrophoretic electronic paper TFT substrate.Finally,in the subject,we uses the high-voltage output chip HV583 to complete the 8-level grayscale drive display of the PDLC material.The analysis of the display effect shows that the multi-level grayscale display drive of the PDLC can be achieved by HV583 with the voltage change of the common pole.DPLC driving experiment based on TFT shows that using TFT substrate can realize PDLC matrix progressive refresh display.By contrast with the dynamic display effect of electrophoretic screen,it is found that PDLC material has a great improvement on the dynamic display effect than the traditional electrophoretic display device.