Development Of Ultrasonic Vibration Assisted Optical Element Molding Machine

Due to the advancement in technology,micro-optical elements with complex shapes are needed increasingly in optical,optoelectronic and bio medical industries.In the techniques of pressurizing molten glass which was poured in a mold is in the forming of glass elements,however,the glass will shrink at the time of cooling and high form accuracy cannot be expected.Therefore obtaining the high form accuracy development of sophisticated technology is essential.Since the glass molding process is an effective approach to fabricate microstructures,and its surface quality strongly depends on the filling capacity of glass at high temperature.To improve the formability and reduce adhesion between the glass and the mold at high temperature,ultrasonic vibration is applied to improve the formability in the molding process.A machine is provided for molding an optical element by using a molding block having upper and lower molding dies,a sleeve dies and a glass blank combined integrally with each other.The machine includes a molding chamber,heating system,loading system and vibration system.Upper and lower molding dies,a sleeve dies as well as glass blank are heating and cooling by heating system in molding chamber.Loading system supplies force in glass pressing,and its loading velocity and magnitude of force can be adjusted based on this size of glass elements.Vibration system is essential to form sophisticated elements,the theoretical FEM analysis on designed horn is simulated in this paper.The influence of temperature on the resonant frequency of the horn is discussed;the structural dimensions of the horns under different molding temperature are optimized based on the simulation results in order to improve the stability of vibration horn under high temperature,and the horns used for different molding temperatures are manufactured.The detected resonant frequency of optimized horn is very close to the simulation results,and it is still stable at high temperature,therefore the vibration stability of the horn is improved.