光学 精密工程, 2013, 21 (3): 575, 网络出版: 2013-04-08
用彩色CCD相机测量发光二极管显示屏的色度
Measurement of chroma of LED displays with color CCD camera
发光二极管显示屏 彩色CCD相机 自适应矩阵 色度测量 亮度测量 Light Emitting Diode(LED) display color CCD camera adaptive matrix chroma measurement brightness measurement
摘要
提出了一种高精度色度计和彩色CCD相机相结合快速测量发光二极管(LED)显示像素的亮度和色度的方法。首先, 用彩色CCD相机测量LED显示像素, 通过图像处理提取每个LED显示像素点在RGB颜色空间中的亮度值和色度值。然后, 建立RGB颜色空间和CIE1931XYZ颜色空间的多通道自适应矩阵, 并使用色度计对部分LED显示像素点进行精确测量, 基于精确测量值和对应的RGB值计算出自适应矩阵。最后, 通过自适应矩阵计算出所有LED显示像素的亮度和色度值。实验结果表明:自适应矩阵大小合适的情况下, 该方法计算出的数据与色度计测量数据之间的色差值ΔE<1,在人眼视觉中的颜色差异轻微, 可快速、精确地采集LED显示像素的亮度和色度值, 实现LED显示屏的高精度亮度、色度校正, 从而大幅提高LED显示屏的显示效果。
Abstract
A method by combination of a colorimeter and a color CCD to measure the brightness and chroma of color pixels of a Light Emitting Diode(LED) was proposed. Firstly, the color pixels of the LED were processed by the CCD camera and the brightness and chroma values of the LED pixels in RGB color space were calculated by image processing. Then, the multi-channel and adaptive matrix between RGB color space and CIE1931XYZ color space were established and the measured data of a few LED pixels were obtained by the colorimeter. With the RGB values and the measured data, the adaptive matrix could be calculated. Finally, the tristimulus values of the LEDs were calculated with the adaptive matrix. Experimental results indicate that the color difference between calculated data and measured data is less than 1 in an appropriate size of adaptive matrix, which can obtain the brightness and chroma of color pixels of the LED rapidly and precisely, and can correct the brightness and chroma of the LED screen. The method can be used to measure hundreds of thousands of LEDs accurately in a short time.
赵梓权, 王瑞光, 郑喜凤, 汪洋. 用彩色CCD相机测量发光二极管显示屏的色度[J]. 光学 精密工程, 2013, 21(3): 575. ZHAO Zi-quan, WANG Rui-guang, ZHENG Xi-feng, Wang Yang. Measurement of chroma of LED displays with color CCD camera[J]. Optics and Precision Engineering, 2013, 21(3): 575.