In 1972, Union Carbide Company of the United States successfully developed the R-θ mode aspherical surface creation processing machine. This is a dual-coordinate CNC lathe with position feedback, which can change the rotation angle θ and radius R of the tool seat guide rail in real time to achieve mirror machining of aspheric surfaces. The processing diameter is up to φ380mm, and the shape accuracy of the processed workpiece is ±O. 63μm, the surface roughness is Ra0.025μm.
Moore Company first developed the M-18AG aspheric processing machine tool controlled by 3 coordinates in 1980. This machine tool can process various aspheric metal mirrors with a diameter of 356mm.
The British company Rank Pneumo introduced to the market in 1980 the use of laser feedback control.
Two-axis linkage machining machine tool (MSG-325), the machine tool can process aspherical metal mirrors with a diameter of 350mm, the shape accuracy of the workpiece is 0.25-0.5μm, and the surface roughness Ra is 0.01-O. 025μm. Subsequently, ASG2500, ASG2500T, Nanoform300 and other machine tools were launched. On the basis of the above-mentioned machine tools, the company developed Nanoform600 in 1990. This machine tool can process aspherical mirrors with a diameter of 600mm, and the shape accuracy of the processed workpiece is better than 0 .1μm, the surface roughness is better than 0.01μm.
The ultra-precision diamond lathe that represents the high level of today's members is the American Lawrence. LODTM, which was successfully developed by Livermore (LLNL) laboratory in 1984, can process workpieces with a diameter of 2100mm and a weight of 4500kg, and its machining accuracy can reach 0.25μm, and the surface roughness is RaO. 0076μm, the machine can process plane, spherical and aspherical surfaces, mainly used for processing parts required for laser fusion engineering, parts for infrared devices and large-scale celestial mirrors.
Large-scale ultra-precision diamond developed by the Institute of Precision Engineering (CUPE) at Cranfield University, UK
The right mirror cutting machine can process aspheric mirrors (conical mirrors with a maximum diameter of 1400mm and a maximum length of 600mm) for large X-ray astronomical telescopes. The institute has also successfully developed a diamond cutting machine that can process the inner gyroscopic paraboloid and the outer gyroscopic hyperboloid mirror of the X-ray telescope.
The ultra-precision machining machine tools developed in Japan are mainly used to process lenses and mirrors required for civilian products. Currently, the machining machine tools made in Japan include: ULG-l00A (H) Fujikoshi developed by Toshiba Machinery ASP-L15, Toyota Koki AHN10, AHN30×25, AHN60—3D aspheric surface processing machine tools, etc.