三通道PWM的数控调光调色方法

A Digital Dimming Color and Intensity Method of Three-channel LED

针对目前机器视觉光源存在工作时间长、需要现场工作人员手动调试、发热严重、适应能力差等问题,提出了一种基于PWM的数字控制光源,建立了混色光下三通道占空比与光照度的函数关系,分8种情况讨论,并分析了该模型的局限性。从调光原理、驱动原理和控制原理3方面详细说明了该数控光源的实现方法,并且对本文提出的数学模型进行了4种有代表性的实验测试。实验结果表明,该数学模型能满足大多数比例的混光模型,实现光源颜色、照度可调,上述问题均可得到良好的解决,同时提高光源寿命、节约能源。

In machine vision,there are many problems exist in light-source,like long running times,manual debugging,heating seriously and poor adaptability.Accordingly,a digital dimming method of light source was proposed based on PWM technology,which was divided into eight situations.The limitation of this model was pointed out and the principals of the digital light-source was declared from three aspects:dimming theory,control theory as well as driving theory.In the meanwhile,four representative experiments were showed out.The results show that this method can satisfy most proportion of the mixed light models,and realize the adjustment of color as well as the change of illumination.With the function of trigger control,the above problems can be solved properly,at the same time,postponing aging of light-source and energy saving can be achieve as well.