3D measurement of complex micro-structures has becoming increasingly important for precision manufacturing. In this paper, a multi-angle Scheimpflug projection 3D microscope (MASP-3DM) is proposed, and the detailed design procedure is given. The system deployed four Scheimpflug projections and one telecentric imaging to overcome the shortcomings of limited depth of field (DOF), occlusion and reflection. Then, an improved and practical system calibration method is proposed, which utilizes pinhole projection model to calibrate the telecentric imaging. Meanwhile, local homography is combined with perspective-n-point (PnP) strategy to improve the calibration accuracy. Further, a point-cloud registration error correction model is established to achieve complete and high-precision measurement. The experimental results indicate that the re-projection error is within ±0.5μm and the registration error is less than 2μm for system calibration, the maximum of mean deviation, measurement bias, standard deviation, and type A uncertainty are respectively less than 3μm, 7μm, 4μm, and 1μm for 3D measurement, within the 10(H)mm×50(W)mm×40(D)mm volume.

复杂微结构的 3D 测量对于精密制造变得越来越重要。本文提出了一种多角度Scheimpflug投影3D显微镜（MASP-3DM），并给出了详细的设计过程。该系统部署了四个 Scheimpflug 投影和一个远心成像，以克服有限景深 (DOF)、遮挡和反射的缺点。然后，提出了一种改进且实用的系统标定方法，利用针孔投影模型来标定远心成像。同时，将局部单应性与透视n点（PnP）策略相结合以提高标定精度。进一步建立点云配准误差修正模型，实现完整、高精度的测量。实验结果表明，系统标定重投影误差在±0.5μm以内，配准误差小于2μm，平均偏差、测量偏差、标准偏差和A类不确定度最大值分别小于3μm、7μm 、4μm和1μm用于3D测量，在10( H ) mm ×50( W ) mm ×40( D ) mm体积内。