dc.description.abstract | In this thesis, we provide an regulation and calculation technique for simulating LED parallel exposure. It can be used to simulate the result of poor exposure which comes from the light decay of the UV-LED or the deviation of secondary optics in parallel exposure machine. The illuminance distribution of the light source group including a single LED and secondary optics is modeled by establishing an illuminance distribution function of a ratio of each distance from the target plane D to the source diameter S (D/S Ratio, DSR). Then optimize the source-to-source spacing by illumination superposition theory and secondary derivative method. After that, add the source group deviation parameters of the scanning parallel exposure machine to calculate the optimal spacing. Next, establish a virtual light source for the reflective element to increase the available working area. Finally, the regulation algorithm for simulating LED parallel exposure is completed.
Since the fabrication of secondary optics components with UV-LED is not easy, some slight errors can cause uneven light distribution. Due to the possibility of simulation and implementation verification in future, this study replaced the actual UV-LED with white light LED as an analog light source. We model the illuminance simulation by using the nonlinear least squares method. Then, we consider the actual source deviation and establish a light distribution function that includes linear and angular offsets. The light distribution function of the light source array is established by the superposition principle of the mathematical function. The parameter of the light source offset refers to the way continuous tracks drive the light source to perform periodic scanning exposure. Straight offset at ± 0.005mm as normal distribution, and angle offset at ±0.5 degrees for normal distribution. In the case of no deviation,
According to the design results, in the case of no offset, the illuminance uniformity of DSR=8, 10, 12, 14, 16, 20 is greater than 94%. In the case of offset extremes, the illumination uniformity of each DSR is greater than 93%. In the case of random number offset, the larger the DSR, the more obvious feature of the angular offset to the light source offset. Illumination uniformity is reduced. Therefore, the DSR of 8, 10, 12 will have better illuminance uniformity results. The last, establish the algorithm of the reflective element by creating a virtual light source. The available working area of each DSR is increased. When DSR is 12, the available working area is increased from 140×140〖mm〗^2 to 150×150〖mm〗^2. The available working area is increased by about 14.7%. | en_US |