In order to express the phase on every plane, a two-parameter second-order rational polynomial is proposed, and then a first-order Taylor series expansion is employed to obtain the polynomial coefficients based on the iterative least-square method.

• 本文提出用二元二次有理多项式模型来描述不同高度的参考面上展开相位分布，并用一阶泰勒级数展开实现了最小二乘迭代求解。