The application of Neural Networks to the luminance and color uniformity for the LED modules
| Autor: | Zhi-kai Xu, 徐志凱 |
|---|---|
| Rok vydání: | 2011 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 99 The technologies used for the brightness and color testing of the LED (Light Emitting Diode) modules on the market, are mostly remain in the manual ways, manual inspection could induce the human errors and cause the damage of human eyes. Due to the different operators, timing and environment, the results of the inspection might be different. The study is utilizing the concept of the neural networks, using the back-propagation neural network method, to construct a LED module automatic inspection system. The uniformity of the brightness and the color deviation of the module were tested. The CCD camera captures the red, green, and blue grayscale values from the samples under test, the captured data are divided into 3 different bins, one for the learning, one for the testing and retraining, and one for the final accuracy conformation purpose. The optical centroid qualified method is used for the LED RGB gray level images. The results of the study are fairly reasonable, some deviations are caused by the environmental factors, adding these samples to the learning bin, making some repeated learning, and the acceptable results are obtained. The fuzzy logic methodology is considered to be the future study for the advanced research, and more stable results would be expected. Keywords: LED, neural networks, back-propagation |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|