This project belongs to the field of high-precision optical metrology and industrial testing. In the rapid development of science, technology and economy in China, high-precision measurement, especially nano-precision detection technology, plays an important role. A large number of high-quality optical surfaces are used in some major international scientific projects such as the Gravity Wave Detector (LIGO) and the National Ignition Facility (NIF) of the United States; laser inertial confinement fusion prototypes, space gravitational wave detection, Shanghai Light Source, Sky One, etc. are also in large demand for precision optical components. A large number of optical devices and systems are also used in semiconductor chips, aerospace, optical fiber communications, machine vision, intelligent control, security systems and digital products. High-end testing instruments and advanced testing technology are necessary conditions to ensure the manufacture and use of high-precision components and optical systems. At present, domestic high-end testing instruments are mainly monopolized by foreign companies. Therefore, the development and localization of high-end testing instruments is an inevitable trend in scientific research and industrial upgrading. Aiming at high-precision surface (surface shape and defect) and transmitted wavefront detection, the project team carried out research on key technologies of interferometry and developed a modular interferometer. With the support of multiple national, provincial and ministerial projects, a number of innovative technologies for high-precision measurement were invented through school-enterprise cooperation, and a number of upgraded laser interferometers and defect detectors were finally integrated and produced. Its innovations focus on: 1. Modular integrated laser interferometer and absolute surface shape detection technology: The interferometer modular technology was innovatively invented to meet the application needs of different fields by matching different modules. In particular, absolute detection technology breaks through the limit that the planar relative detection accuracy PV value is better than lambda;/20, and can reach lambda;/100. The repeatability accuracy is 60% higher than that of similar foreign interferometers, greatly improving the existing instrument detection level. 2. Broadband wavefront detection technology for transmitted optical systems: Invented a method for detecting the transmitted wavefront of optical systems using an interferometer. Broadband wavefront detection is realized by studying the relationship between wavefront and wavelength, breaking through the limitation that existing instruments can only detect wavefronts at specific wavelengths. 3. Special revolution surface shape detection technology: For the surface shape detection of special components, a method for detecting surface shapes such as the outer surface of a cylinder, the inner surface of a hollow cylinder, the inner groove surface of an annular guide rail and the outer groove surface of an annular guide rail has been invented. 4. Rapid optical defect detection technology: Based on the laser-induced thermal wave effect, a rapid and high-sensitivity detection method for optical surface absorption defects has been invented, breaking through the limitation of low detection efficiency in the existing art. A total of 25 million yuan has been invested in this project, and the economic benefits have reached more than 50 million yuan. A variety of laser interferometers and defect detectors have been developed using inventive technology, providing testing instruments and technical support for many users in industries such as flat crystal flatness measurement, high-precision optical-mechanical component surface shape and defect detection, and transmitted wavefront detection. Innovative upgrades of the whole system technology and performance. Among them, plane absolute inspection technology is adopted by many metrology institutions such as China Institute of Metrology and Beijing Great Wall Institute of Metrology and Testing Technology for first-class flat crystal calibration and testing. At the same time, it is also negotiating cooperation matters with the German Institute of Metrology (PTB) and the British Institute of Metrology (NPL). Component surface shape and transmitted wavefront detection technology serves many units such as Changchun Institute of Optics, Precision Mechanics and Physics, Chinese Academy of Sciences, Shanghai Institute of Optics and Precision Mechanics, Changfei Optical Fiber and Cable Co., Ltd. High-end instruments and advanced technologies provide important equipment guarantee and technical support for the performance testing of China's high-precision components and optical systems, and promote the rapid transformation of China's laser interferometer standards, testing procedures, and calibration specifications. The total number of patents in this project is 30, including 8 authorized invention patents and 6 utility model patents. 10 invention patents and 6 utility model patents have been applied for, and more than 80 papers have been published.