孔令豹教授指导的研究生获CJUMP2025会议最佳论文奖

孔令豹教授指导的研究生获CJUMP2025会议最佳论文奖

Chromatic confocal measurement (CCM) is an extensive technique of confocal microscopy, where the inherent relation between the focused wavelength and the axial position enables depth sensing. Most CCM works by single-point, resulting in inevitable lateral scans for 3D measurement. To facilitate the process, a 3D measurement method was developed, characterized by combining depth obtained by chromatic confocal technique and lateral information obtained by DMD. To realize the field extension, an objective with hyper-chromatism and wide field was custom-designed to form a 16 x 16 x 5.2 mm3 measurement range. Chromatism was decoded to depth by creating a spectral bar for each measurement point. As depth varied, the peak intensity was observed to shift linearly on a pixelized bar. An effective range of 10 x 10 x 3.35 mm3 was obtained from calibration. To validate the 3D measurement ability, a planar mirror, a three-step height sample of a 10 x 8 mm2 field of view (FOV) with 0.1 mm and 2.0 mm height and a letter "V" structure were tested. Current work proves the array-based chromatic confocal technique can be a promising 3D measurement approach of practical significance. (c) 2025 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.

Significance Freeform surfaces have been regarded as one of the major revolutions in the field of modern precision optics. They are expected to further promote miniaturization, lightweight and integration of optical systems due to their excellent optical and mechanical properties. The quality of machined freeform surfaces will significantly influence the performance of optical systems. Surface metrology including the measurement of surface texture and surface form errors is the important post-manufacturing part to determine which surface can be employed. In the past decades, various methods have been developed for measuring and characterizing freeform surfaces, mainly including probe- based scanning, fullaperture optical inspection, on- machine measurement technology, feature-based surface registration and multi- scale data fusion methods. Although many corresponding advances have been achieved, great challenges are posed to the quality of surface manufacturing with the complexity of freeform surfaces increasing. Moreover, the surface form error is required to be lower than 0. 1 mu m and the surface roughness should be less than 1 nm. It is urgent to develop a new measurement technology for achieving a higher dynamic range and a higher accuracy. Hence, it is important and necessary to summarize the existing research to guide the future development of this field more rationally.

In machine vision systems, the objectives to be detected, such as circuit boards, may be composed of many different materials and shapes, which can lead to highlights, shadows and error information in captured images under traditional uniform illumination. A lighting system that generates tailored irradiance in different regions in machine vision is needed. This paper proposes a design method for an LED lens and obtains special total-internal-reflection (TIR) lenses that generate tailored illumination, which can adapt to the reflectance and shape of a target. Differential-algebraic equations (DAEs) based on the conservation of flux are established to ensure the uniform illumination on the targets, nonlinear equations based on the edge-ray principle are employed to generate the spots with tailored shapes and the numerical solutions can be fitted into the proposed lenses. Six different tailored faculae are generated to verify the proposed method. The results show that the uniformity of tailored facula can exceed 87%, and the light efficiency can exceed 85%. In particular, the contrast of the irradiance among different regions can be adjusted by the boundary conditions; thus, the proposed method can satisfy the complex demand for machine vision and be applied to improve vision detection systems in production lines.

The in-situ measurement of complex optical surfaces is a challenging task in precision engineering. The phase measuring deflectometry is a powerful measuring method for complex specular surfaces, and it has higher measuring efficiency, stability and dynamic range compared to interferometry. Consequently it is promising to widespread applications in various fields. Deflectometry is essentially a calibration problem, and the measuring accuracy is directly determined by the quality of geometrical calibration. An in-situ deflectometric measuring system is designed based on the single point diamond turning machine. A self-calibration method is developed to specify the relative positions of the camera and screen. Ray tracing is conducted at two positions of an auxiliary reflecting mirror, which is mounted on an air bearing spindle. The accuracy of the geometrical positions can be improved by an order of magnitude by minimizing the deviations of the traced points with respect to the true correspondences. According to the statistical properties of the deviations in reverse ray tracing, the form errors and the position errors can be separated, and the positioning error of the workpiece can be corrected accordingly. Henceforth, the nominal shape of the fabricated workpiece can be fully utilized, and the conventional one-way position-form mapping can be converted into a two-way mapping problem. As for the complex shapes, the whole surface can be covered by sub-aperture measurement. Precise localization of a local region under test is achieved by multi-position imaging, so that correct convergence of the iterative reconstruction process can be guaranteed. Several typical optical surfaces including an off-axis paraboloid mirror are measured, and the measuring accuracy of the proposed method is proved better than 150 nm RMS.

徐敏研究员等参与的项目《纳米精度材料加工面型及形变干涉计量关键技术及其应用》获上海市科学技术奖科技进步二等奖

费义艳副教授作为主要完成人之一，参与项目《亨廷顿病的机制与靶向干预策略研究》获得2024年度上海市科学技术奖自然科学一等奖

孙树林教授团队成果《基于超构表面的全空间多通道高效率复杂光场调控》获第八届微纳光学技术与应用交流会光学超构材料优秀成果奖

韩伟青年研究员研究团队论文获《极端制造》期刊最佳论文

张祥朝、徐敏、王伟等组成的科研团队研发的“自由曲面偏折测量仪”项目荣获2022年“日内瓦国际发明特别展”金奖

针对多面共体自由曲面光学系统精密制造的高精度检测问题，提出多面共体自由曲面光学测量与表面表征方法，突破自由曲面元件纳米级测量涉及的跨尺度三维扫描测量坐标基准及高精度轴向瞄准触发测量共性技术瓶颈，利用归一化激光差动共焦技术实现抗曲面倾角变化的高精度自由曲面定焦触发测量

掌握弱刚性构件形位误差与表面缺陷的非接触精确测量方法，揭示弱刚性曲面构件轮廓、壁厚等形位误差测量过程中多源误差耦合机理，建立几何误差与表面缺陷的评定算法与识别技术。

面向IC装备中以晶圆工件台或掩膜板工件台方镜的制造，突破硬脆材料多尺度复杂功能结构光学零部件的制造难题。作为核心部件，它们在惯导系统、精密测量系统、超精密制造等领域也有重要应用。