In the 1960s, precision machining technology was developed to meet the needs of advanced technologies such as aerospace and military industry. By the beginning of the 1980s, its maximum dimension accuracy has reached 10 nanometers (1 nanometer = 0.001 micron), surface roughness has reached 1 nanometer, and the minimum dimension has reached 1 micron. It is advancing towards the goal of nanometer dimension accuracy. Nano-scale ultra-precision processing is also known as nano-technology. Ultra-precision machining is an interdisciplinary and comprehensive technology in development. From the 1950s to the 1980s, it was the beginning of technology. In the late 1950s, the United States took the lead in developing ultra-precision machining technology to meet the needs of the development of advanced technologies such as aerospace and national defense. The technology of single point diamond turning (SPDT) for diamond cutting tools, also known as "micro-inch technology", was developed to process laser fusion mirrors, tactical missiles and spherical surfaces for manned spacecraft. Large aspheric parts, etc.

Introduction: In the 1960s, in order to meet the needs of advanced technologies such as nuclear energy, large-scale integrated circuits, lasers and aerospace, high precision processing technology was developed. The precision of ultra-precision machining is more than one order of magnitude higher than that of traditional precision machining. By the 1980s, the processing dimension accuracy could reach 10 nanometers (1 *10-8 meters) and the surface roughness could reach 1 nanometer. Ultra-precision machining has special requirements for workpiece material, processing equipment, tools, measurement and environment. It requires comprehensive application of precision machinery, precision measurement, precision servo system, computer control and other advanced technologies. The workpiece material must be extremely meticulous and uniform, and properly treated to eliminate the internal residual stress, ensure the dimensional stability of the height, and prevent deformation after processing. Processing equipment should have very high motion accuracy, the straightness of guide rail and spindle rotation accuracy should reach 0.1 micron level, and the micro feed and positioning accuracy should reach 0.01 micron level. Strict environmental conditions are required. Constant temperature, humidity and air cleanliness should be maintained, and effective vibration prevention measures should be taken. The system error and random error of the machining system should be controlled at 0.1 micron or less. These conditions are obtained by comprehensive application of advanced technologies such as precision machinery, precision measurement, precision servo system and computer control.