| Cylindrical lens and cylindrical array lens play an important role in laser shaping,light and holographic imaging.Especially,Laser shaping with cylindrical lens or cylindrical array lens is an ideal method,which has ideal shaping effect,low energy loss and simple structure.With the increase of using of laser,the demand for cylindrical array lens will increase sharply.The traditional processing method of cylindrical array lens has disadvantages of low precision,long period and unsuitable for mass production.Glass lens molding has high precision and high consistency.It is suitable for mass production and can overcome the disadvantages of traditional processing methods.But at present,researches of glass lens molding technology mostly focus on small aspheric lens,and researches on micro-structured array glass lens are less,and it is still in the stage of regular shape array,such as rectangular groove and V groove.In addition,finite element simulation,as a common research method in glass molding technology research,is not accurate enough for material parameters and friction coefficient of glass-die interface during molding process.In view of above problems,friction coefficient of glass-die interface is measured first,then a finite element model is established and molding process of cylindrical array lens is simulated.The influence of die structure and molding process parameters on stress and filling effect of cylindrical array glass lens is investigated.The main research work is as follows:(1)Using new optical glass K-LCV161,copper-nickel alloy C71500 and tungsten carbide J05,the friction coefficient of glass-die interface is measured by a method of traditional barrel pressure test.The results show that friction coefficient between glass and die material varies little in different molding temperature,but changes greatly when using different die materials.(2)Using simulation software MSC.Marc,molding process of cylindrical array glass lens is simulated and analyzed.The effects of different die structures on filling rate and stress of cylindrical array glass lens are compared and analyzed.It is found that increasing groove spacing can reduce maximum stress of die in molding process,and increasing of molding temperature will decrease maximum stress of glass.The profile is predicted by using optimal molding parameters after annealing and cooling.(3)The experiment of molding cylindrical array lens is carried out,and shape profile and surface roughness of the upper and lower die surfaces before and after experiment are compared.The influence of molding temperature and molding force/molding rate on profile deviation of lens is investigated by single factor experiment.The results show that profile deviation and surface roughness of the upper and lower die have increased before and after experiment,molding temperature has a great influence on profile deviation,and molding force/molding rate has little effect on profile deviation. |
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