The grating projection‐based three‐dimensional (3D) measurement technique has been widely used in various fields, such as industrial inspection, cultural relic protection, and reverse engineering. However, due to the nonlinear response between the input and output of the measurement system, phase measurement errors occur, which reduces the accuracy of 3D reconstruction, which is known as the gamma effect. To address this issue, a novel method has been proposed to reduce the nonlinear response of the system. Ultimately, this method reduces the impact of the gamma value on the phase accuracy in subsequent measurements. Experimental results have shown that this method can quickly calibrate the correct precoding gamma value, effectively reduce the gamma nonlinear response during the measurement process, and improve measurement accuracy.