多通道LED光源的光色预测模型研究  

Color Prediction Model of Multi-Channel LED Light Sources

作　　者：章夫正 孙士琪 卢弘达 李遂贤 Zhang Fuzheng;Sun Shiqi;Lu Hongda;Li Suixian(Flight College,Shandong University of Aeronautics,Binzhou 256600,Shandong,China)

机构地区：[1]山东航空学院飞行学院,山东滨州256600

出　　处：《光学学报》2024年第20期294-302,共9页Acta Optica Sinica

基　　金：山东省自然科学基金(ZR2022QE160)。

摘　　要：基于多通道发光二极管(LED)光源的发光特性,提出了一种预测多通道LED光源三刺激值的三阶段模型。该模型包括三个子模型:通道响应特性表征模型、单通道光色预测模型,以及通道叠加模型。通道响应特性表征模型解决了LED对控制信号的非线性响应问题,单通道光色预测模型考虑了LED色品随控制信号发生变化的问题,通道叠加模型表征了多通道混光的加和性。分别采用具有10 bit调光分辨率的四通道(脉宽调制调光)和七通道(模拟调光)LED光源对模型的预测精度进行了实验。结果表明,所提出的模型在亮度和色品预测精度方面均显著优于线性模型,亮度误差百分比平均值分别为1.13%和1.18%,CIE 1976 UCS色品差平均值分别为0.99×10^(-3)和0.81×10^(-3)。Objective Multichannel LED light sources(MCLLSs)offer numerous advantages over traditional light sources in terms of spectral tunability and dimming control.These advantages have gained wide attention from the lighting community over the past decades.However,controlling the color produced by MCLLSs has always been a challenging problem in the lighting community.Traditionally,it is assumed that the photometric quantities produced by MCLLSs are proportional to the control signal,such as the driving current for analog dimming and the duty cycle for the pulse width modulation(PWM)dimming.However,each single LED channel of practical MCLLSs tends to show nonlinear response and chromaticity variability due to chip material,junction temperature,driving circuit,and control signal modulation.Existing color mixing algorithms based on the linear hypothesis lead to poor mixing accuracy.A highaccuracy color mixing algorithm depends on accurately characterizing the luminous properties of MCLLSs.A threestage color prediction model is therefore proposed to predict the CIE 1931 tristimulus values of MCLLSs in our study.Methods The proposed color prediction model is composed of three stages.The first stage characterizes the nonlinear response of individual channels,i.e.,the characterization model for channel response property,which can transform the control signal value of an LED channel into one of the CIE 1931 tristimulus values of the channel based on a polynomial fitting method.The polynomial of each channel can be obtained by fitting a training sample dataset.The training sample dataset is constructed by measuring the CIE 1931 tristimulus values and chromaticity coordinates of a ramp control signal sample for each single channel.The second stage predicts the remaining two CIE 1931 tristimulus values of each channel by accounting for chromaticity variability.Chromaticity variability is overcome by searching for the chromaticity coordinates at the nearest control signal sample in the training sample dataset.The last stage is the

关 键 词：视觉光学 照明 多通道LED光源 光色预测 三刺激值 

分 类 号：O432[机械工程—光学工程]