基于结构光的主动视觉测量技术因具有诸多优点在工业测量领域得到广泛应用,而投影仪和相机组成的测量系统的Gamma非线性、系统抖动以及噪声等因素,均易导致相位和三维测量结果出现较大误差。针对测量系统出现的Gamma非线性问题以及投影仪亮度分布不均匀导致Gamma值不同,投射单一灰度的图像于表面光滑的均匀白板,利用灰度特征对采集图像进行分区和直方图统计,建立不同区域的模型后,进而完成对初始相位的补偿。在求解相位之前,为避免系统抖动和噪声影响相位误差对图片进行预处理。将该方法应用于实际测量中,相位精度和测量精度大幅提高,该方法比已有的消除Gamma非线性影响的方法更简单方便。

Active light measurement based on structured light is widely used in industrial measurement for its several advantages, while the Gamma nonlinearity, vibration, and noises easily lead to phase error and effect accuracy of three-dimensional measurement. Due to Gamma nonlinear problem for measurement system and different brightness distributions of projector, the system has different Gamma values. An image is projected on a standard whiteboard with smooth surface, and partitioned by using grayscale feature by histogram statistics. According to sub-regional information target area of the projector sub-area information is obtained to establish different regions modelling, which is used to compensate initial phase. To avoid system jitter and noise, original image is pre-processed before solving the phase. Applying this method to actual measurement, precision and accuracy of phase are greatly improved, and the method is simple and convenient, compared with existing methods of eliminating the nonlinearity of Gamma.