Overview: How to further improve the lightweight ratio of high-performance meter-level space mirrors is one of the core issues in the field of large aperture optomechanical structure design. In this paper, a primary mirror blank with a clear aperture of Φ1200 mm was developed for a high-resolution space camera, which achieves the goal of designing area density below 40 kg/m². The SiC mirror blank was manufactured by gel injection molding and reaction sintering process, with the classical back three-point support scheme together with the testing state of the optical axis being horizontally adopted to simplify the supporting structure. Novel lightweight measures such as an alternate arrangement of main and auxiliary stiffeners and the addition of lightweight holes to vertical walls were used inside the semi-closed blank, which further improves the lightweight ratio of space mirrors with the sandwich structure. Distributed datums were proposed to replace the traditional datum setting, which reduces the machining area of datums by more than 80% and improves machining efficiency significantly. A robot arm is used for polishing in optical processing, and the local surface deformation is 47 nm in PV value under the typical polishing pressure of 1.77 kPa, with the mirror surface of 4 mm thick and the spacing between stiffener ribs of 81 mm. A parametric model of the mirror blank was built with shell elements, which contains ten variables including stiffener thickness and blank height, and integrated optimization was carried out so as to determine the optimal combination of structural parameters, using the multi-island genetic algorithm. The final design weight of the mirror blank is 46.9 kg, with corresponding area density of 38.8 kg/m². The RMS value of self-weight deformation of the mirror blank is only 2.87 nm with its optical axis being horizontal, and the free fundamental frequency is 602 Hz, indicating that the mirror blank has good dynamic and static characteristics, which satisfies the design requirements of space cameras. After machining, the measured weight of the mirror blank is 51.3 kg, about 9.4% overweight than the design, and the facesheet is about 1 mm thicker, mainly caused by the inhomogeneity of the molding process. During the centroid position test of the primary mirror blank, the deviation between the measured and theoretical centroid position is about 3.7 mm in the axial direction and 2.0 mm in the radial direction, which can be compensated through adjustment of the supporting structure and has limited influence on the optical performance of mirror assembly. At present, the primary mirror blank has already been polished to RMS λ/8 (λ=632.8 nm) of surface shape accuracy, with no obvious print-through effect observed. The lightweight structure scheme and optimization method of the mirror blank proposed in this paper can provide an important reference for the design of similar space mirrors with the characteristics of large aperture and low areal density.

报道了一种新型的Mn⁴⁺掺杂水合六氟钛酸钙CaTiF₆·2H₂O∶Mn⁴⁺红色荧光粉，详细研究了基质的结构转变和荧光粉的发光性能及高显色指数（显指）暖白光LED应用。CaTiF₆·2H₂O∶Mn⁴⁺在130~200 ℃间脱水转化为CaTiF₆∶Mn⁴⁺，荧光光谱发生改变，重新吸附水分子可恢复到CaTiF₆·2H₂O∶Mn⁴⁺，发光性能不可逆。重要的是，该荧光粉在较长波626 nm和635 nm处分别发射锐线极强的零声子线（ZPL）和ν₆振动峰，色坐标为（0.701，0.299），更接近人眼敏感的红光边界650 nm（色坐标x~0.72，y~0.28），有助于提高暖白光LED的显色指数、拓宽背光源的色域。晶体结构和晶体场强度计算指出，Mn⁴⁺在CaTiF₆·2H₂O∶Mn⁴⁺中占据低对称性的格位，所受到的晶体场强度较弱，Mn—F键的共价性较强。另外，通过表面疏水化显著提升了荧光粉耐湿性能，共掺小离子半径的Si⁴⁺增强了荧光粉发光热稳定性。以CaTiF₆·2H₂O∶Mn⁴⁺作为红光成分，获得了高显色指数（R_a=90，R₉=68）的暖白光LED，在高品质的暖白光照明中具有潜在的应用。

大口径长条形反射镜是大型离轴三反相机的核心部件之一，针对“吉林一号”宽幅01C星中通光口径为1250 mm×460 mm的主反射镜，系统论述了1.2 m量级大长宽比反射镜组件的结构设计方法，并对所研制的主镜开展了详细的验证。从材料属性和现有工艺出发，镜体材料选择反应烧结碳化硅，采用半封闭式轻量化形式，通过二目标全局优化确定了镜体结构参数的最佳组合，最终镜体设计质量为41.8 kg，面板厚5 mm、最薄加强筋仅厚3 mm。采用经典背部三点支撑方案，优化柔性支撑中的双轴柔性铰链结构参数以兼顾组件基频和热稳定性，并与镜体质心位置进行匹配。提出了主镜组件的装配流程和相应的消应力措施。测试结果表明：主镜在装调重力工况下全口径面形精度均方根值为0.016λ(λ=632.8 nm)，翻转180°后主镜全口径面形精度均方根值为0.019λ；实测主镜组件一阶基频为127.8 Hz，经大量级随机振动和高低温循环后，主镜面形精度均方根值基本不变。主镜组件具有良好的动、静力学特性，且面形精度高、稳定性良好，能够满足高性能空间光学系统的使用要求。

在大口径、长焦距空间遥感相机中，主、次镜间相对位置变化会影响相机的成像质量和稳定性，因此，作为主次镜间承力结构的主次镜支撑结构，是相机设计过程中的关键一环。本文针对大口径、长焦距相机特点，设计并研制了碳纤维薄壁筒式主次镜支撑结构。首先，根据给定光学系统，选取了筒式基结构形式。然后，根据筒式基结构形式的特点，依次对筒式结构的次镜支撑梁和纵向加强筋的几何结构形式进行了分析与选型。接着，为了充分发挥碳纤维材料铺层可设计性特点，对主次镜支撑结构进行了结构关键尺寸、铺层厚度和铺层角度三者的迭代优化设计，并对设计结果进行了有限元仿真分析。最后，通过测量次镜角度变化量和特征级扫频振动试验，验证了支撑结构的稳定性和结构刚度。试验结果表明：次镜相同状态下长期监测差值变化量小于1.5″，重力翻转前后变化量小于1.08″，支撑结构一阶固有频率大于115 Hz，轴向频率大于180 Hz，表明主次镜支撑结构具有良好的刚度和结构稳定性，满足设计指标要求。