| Since OLED had been reported at 1987, OLED has developed rapidly because of its features that it adopts the EL principle and can issued a strong light without a high voltage. It owns some technology advantages such as high saturation, high reaction speed, wide viewing angle and lower consumption. For these reasons, it has been a new device that can be applied to many aspects such as illumination, display and so on. Moreover, it has gradually played a dominant role in the display field and become the rising star with immeasurable development perspectives. Therefore, we need to find a way, which can use OLED better for the engineering applications and integrate the market products and the application more comprehensive. And it is necessary that looking out an energy-saving display mode to respond to the needs of portable devices. Based on these, this paper carried out the following:In the experiment, the author built the full-color AMOLED drive circuits and the test platform, and treated the pictures which one should be displayed through the human machine interface programs on the PC. Written the pictures test program by the Matlab, by which we find out the 16-bit RGB color values and the grayscale values of the displayed pictures. In the experiment, we also verified the wide-angle characteristic of AMOLED, and tested the current of the different levers of same color pictures and the different grayscale pictures. We do a comprehensive analysis of the current work of the corresponding image, and get some requirements of AMOLED in the engineering attentions. Specific work is divided into two parts, hardware and software.1. By substantially reading pertinent literature and learning about the drive mode and feature of the OLED, we select AMOLED to be the experiment devices which based on the devices'weakness and strength. According to whether it has single pixel driving circuit, the OLED can be divided into two kinds, active and passive. The former has better controllable and electrical characteristics. For the good characteristic of AMOLED, we select LH300WQ1 (240xRGBx400) screen of LG3.0 inches and LGDP4251 driver chip to be our research sample.2. Because there are many kinds of the centre controller electrical products in the market, especially the ones which use AMOLED display, such as mobile phones and MP4, they mostly adopt ARM control system, and MCU capability is limited that it can't reach the request of products, therefore we select ARM7 S3C44BOX as the center controller to approach to the project application. During the test system, we carry out the communication between PC and treat system to display the selection and control of the content, then send the contents to AMOLED display system, and we apply NOR FLASH of ARM development system to store data for receiving and storing the data of 16-bit bitmap.In the paper, we design the power supply circuit of AMOLED monitor, including the effectively supply stable power for AMOLED needed so that the experiment can go on smoothly. Also we reserve test interfaces to make it convenient to test instantaneous current in the system.3. In the PC, by using Matlab, we compile figures, analyze program and establish man-machine interface. First, change the target images for being displayed into 16-bit bitmap format. Second, based on the principle of image color, we calculate R, G, B, H, S, I values and mean gray value of the target images, and then draw histogram, so we can visibly learn about primary features of images, and analyze the color component.4. Tested the currents of displaying different images, and analysis the results of the experiment. We synthetically analyze the image characteristics, such as the instantaneous current, color component, and mean gray value obtained when specific image displays in the test, and then we can get some relationship between the display and consumption of AMOLED. So that we can sum up some characteristics of the energy saving display of AMOLED, for supplying reasonable opinions and suggestions on energy saving display field to engineer manufacture and application, such as:First, the operating current of displaying pure white image is much larger than the black one. Because OLED is a current-driven self-luminous device, when it shows the white image, the red, blue and green pixels are all working at the same time, it makes the consumption of current big. But the current is small while the black is displayed for OLED does not work. This is very different with LCD. Therefore, the use of AMOLED engineering applications should be as little as possible with a white background or the menu bar. In addition, when the black image is being displayed, it still has some component consume in the circuit, such as the pixel drive circuit components in the TFT, the black screen of AMOLED still has some small current flew, not zero.Second, the summation of the operating currents of displaying red, blue and green separately is as same as it of pure white. And the color has the maximum power consumption is pure blue, green is the second one, and the red is the smallest one, so the display can display the requested with less blue.Third, the average gray image and the operating current have proportional relationship, because of that, a specific set of images only has one corresponding gray value, but a set of gray values corresponding to an infinite number of image color schemes, so the relationship of the gray scales and the current complexes. |
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