针对机器视觉检测 TFT-LCD Mura缺陷时存在的图像整体亮度不均匀、背景复杂等影响检测准确性的问题，提出一种基于 B样条曲面拟合的背景抑制方法。在最小二乘法准则的约束下，采用双三次 B样条曲面拟合算法拟合出背景，并添加光顺项调整拟合精度，用原始图像减去拟合背景，从而消除亮度不均匀背景对缺陷分割造成的影响。为提高算法速度，对原始图像进行分块拟合，并将双三次 B样条函数分解为一元函数求解，减小了计算量，同时避免了对原函数求解时容易出现的病态解问题。实验结果表明，该算法准确、高效。

A background suppression method based on B-spline surface fitting was proposed to solve the problem of the accuracy of Mura detection, which is often caused by the uneven brightness and complex background when employing machine vision on Mura detection of TFT-LCD. Under the constraint of least square criterion, bicubic B-spline surface fitting algorithm was deployed to fit the uneven brightness background and a fairing item was added to adjust fitting precision. In order to increase the performance of the proposed algorithm and decrease the calculation time, divided fitting method was used on original image and the bicubic B-spline function was analyzed into one-dimensional functions for efficiently solving. Furthermore, pathological problems caused by solving of the two-dimensional functions could be avoided simultaneously. The effect on the Mura defect segmentation caused by uneven brightness background was eliminated by subtracting the fitted background from the original image. The experimental results show that the proposed method can suppress the uneven brightness background efficiently and Mura defect can be segmented accurately after background suppression.