Author Affiliations
Abstract
State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, China
A concept of divergence angle of light beams (DALB) is proposed to analyze the depth of field (DOF) of a 3D light-field display system. The mathematical model between DOF and DALB is established, and the conclusion that DOF and DALB are inversely proportional is drawn. To reduce DALB and generate clear depth perception, a triple composite aspheric lens structure with a viewing angle of 100° is designed and experimentally demonstrated. The DALB-constrained 3D light-field display system significantly improves the clarity of 3D images and also performs well in imaging at a 3D scene with a DOF over 30 cm.
3D light-field display depth of field divergence angle of light beams compound lens Chinese Optics Letters
2024, 22(1): 011101
Author Affiliations
Abstract
1 School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China
2 College of Electronics and Information Engineering, Sichuan University, Chengdu 610065, China
Light field 3D display technology is considered a revolutionary technology to address the critical visual fatigue issues in the existing 3D displays. Tabletop light field 3D display provides a brand-new display form that satisfies multi-user shared viewing and collaborative works, and it is poised to become a potential alternative to the traditional wall and portable display forms. However, a large radial viewing angle and correct radial perspective and parallax are still out of reach for most current tabletop light field 3D displays due to the limited amount of spatial information. To address the viewing angle and perspective issues, a novel integral imaging-based tabletop light field 3D display with a simple flat-panel structure is proposed and developed by applying a compound lens array, two spliced 8K liquid crystal display panels, and a light shaping diffuser screen. The compound lens array is designed to be composed of multiple three-piece compound lens units by employing a reverse design scheme, which greatly extends the radial viewing angle in the case of a limited amount of spatial information and balances other important 3D display parameters. The proposed display has a radial viewing angle of 68.7° in a large display size of 43.5 inches, which is larger than the conventional tabletop light field 3D displays. The radial perspective and parallax are correct, and high-resolution 3D images can be reproduced in large radial viewing positions. We envision that this proposed display opens up possibility for redefining the display forms of consumer electronics.
tabletop light field 3D display integral imaging compound lens array radial viewing angle Opto-Electronic Advances
2023, 6(6): 220178
1 深圳技术大学中德智能制造学院, 广东 深圳 518118
2 浙江工业大学分布式能源与微网研究所, 浙江 杭州 310014
针对传统机械式切割钻石的加工过程中, 切削力四处传播容易造成钻石损坏, 切割的噪音和粉尘也很大, 加工精度不高等问题, 提出采用激光切割钻石的加工新方式。为了减少实验和加工过程中的盲目性, 分析了钻石激光切割的加工机理, 根据加工过程中温度场和热应力分布, 推导出材料加工阈值和裂纹产生阈值公式, 作为钻石切割的上下参考阈值。并且设计了一款基于软件的532 nm激光切割钻石装置, 装置中采用了具有切割、成像和照明三种功能的新型复合镜头, 保证加工装置不仅能切割钻石, 还能动态显示钻石加工效果; 设计的专用夹具可带动钻石自由旋转, 从而便于用户根据杂质情况任意选择加工位置, 提高加工质量, 减少加工中损耗, 从而实现最优加工。
532 nm激光 钻石加工 阈值 复合镜头 专用夹具 532 nm laser processing of diamond the value of threshold compound lens special fixture
1 浙江工业大学信息工程学院, 杭州 310014
2 中国科学院长春光学精密机械与物理研究所,长春130022
X射线聚焦组合透镜是一种利用折射效应对X射线辐射聚焦的新型元件。针对X射线波段的特性,综合考虑折射和吸收效应得出组合透镜的衍射屏函数,并利用衍射理论推导出X射线组合透镜的设计理论。利用统计学理论中一阶、二阶原点矩表征像面处的光学性能,使设计更简洁。该理论方法可方便地推广到双凹折射单元情况。通过数值计算分析了像面处强度分布的二阶中心矩以及焦点处辐射强度随组合透镜结构参量的变化关系,给出了一种铝基X射线组合透镜的结构参量设计结果。对于设计的组合透镜结构参量,计算了当X射线辐射能量分别为0.93 keV, 9.89 keV和29.78 keV时,X射线辐射经过组合透镜后的焦点强度分布。
X射线光学 X射线聚焦组合透镜 衍射屏函数 二阶中心矩 组合透镜结构参量 焦点光强分布
