（Completed by: China Building Materials Academy Co., Ltd., China Building Materials Optical Fiber Technology Co., Ltd）
The project falls within the realm of new materials and high-tech fields, encompassing key technologies for the preparation of high-resolution, low-defect optical fiber image inverters and their application development in low-light image intensifiers. To build a robust modern national defense and meet the urgent needs of the defense for optoelectronic signal detection and imaging components, with the support of national "863" program, national defense "14th Five-Year Plan", and annual key supporting projects, the research and development team has been collaborating for over two decades to tackle challenges related to high resolution, low defects, and high reliability of optical fiber image inverters. They have successfully solved technical difficulties in image distortion and light defect control of optical fiber image inverters, independently developed high-resolution, low-defect optical fiber image inverters, and achieved full chain autonomy and controllability from materials, processes, technologies to equipment. In 2022, they were awarded the title of Single Champion Product by the Ministry of Industry and Information Technology. Meanwhile, their products have been exported in bulk to countries such as France, the Netherlands, Russia, and Germany, providing a countermeasure against the European Union.
The key technologies and main innovations of the project are as follows:
1. Innovatively designed a high refractive index core material and solved the compatibility challenges between this core material and three different glass properties and processes, including cladding material and absorber material. Established a database of glass material systems for image inverters, laying the material foundation for the preparation of high-performance low-light-level image intensifiers;
2. We have independently developed point-contact optical fiber forming and online wire arrangement technology, as well as complete sets of equipment, achieving high-precision drawing and high packing density arrangement and forming of optical fibers. This has solved the bottleneck issues arising from unexpected deformation and misaligned structures in thermal history optical fibers, reducing the image distortion of fiber inverters to below 5μm;
3. Invented solid glass with high compatibility with fiber core and cladding glass, broke through the high-temperature melting and pressing molding with high uniform distribution of temperature and force fields, and prepared fiber inverters with image distortion rate reduced to below 0.5%;
4. A bidirectional differential rotation calculation model has been proposed, breaking through the high-precision control and equipment manufacturing technology of fiber optic image inverters. This has solved the bottleneck problems of snake-like distortion and image displacement, resulting in the development of fiber optic image inverters with snake-like distortion less than 5μm and image displacement less than 100μm.
The project has achieved 20 national invention patents, 2 international invention patents, 19 utility model patents, and published over 10 SCI papers. Additionally, it has formulated 1 national military standard. The key technologies for the preparation of fiber optic image inverters and the control technologies for optical defects and image distortion have been fully transformed. A research and innovation platform integrating scientific research, product development, process technology, quality control, and industrial preparation has been established. This has formed a production capacity of over 300,000 fiber optic image inverters per year, which are widely used in various types of low-light image intensifiers. In the past three years, it has achieved revenue exceeding 500 million yuan, serving both national defense security and the development of the national economy.
The article is excerpted from "China Building Materials"
Source: [1] Anonymous. Application and Development of Key Technologies for Preparing High-Resolution and Low-Defect Fiber Inverters in Low-Light Image Intensifiers [J]. China Building Materials, 2024(4)