High-speed glass-molding method to mass produce precise optics

摘要

Abstract: We propose a newly developed mass-production molding method for precise glass optics. The aims of this batch-type glass-molding method are as follows: (1) reduction of the molding time; (2) high reproducibility of molding and (3) high reliability of a molding system. The following engineering techniques were developed to achieve these aims: (1) independent distribution layout of multi-molding cavities to reduce thermal capacity and inhomogeneity of the cavity temperature, (2) die-based assembly structure to reduce decentering of the optical axis of the molds, (3) compact and small RF (radio frequency) power supply for rapid heating, and (4) automatic control with high error-recovery rate routines by a computer. As a result, this molding process achieved (1) high-speed molding of small optics, (2) high reproducibility and high production yield, (3) mold life longer than 10,000 shots without any optical surface protective coating, (4) high repeatability of molding conditions, and (5) high reliability of a molding system. Consequently, an average wave aberration of less than 0.025 $lambda rms of a molded aspheric collimator (NA0.40) for laser beam printers $phi 6.8 mm $MUL t 5.6 mm in size and 40 s/piece tact time were achieved in large-capacity production.!3