Research on Slow Tool Servo Machining of Complicated Planar Microlens Array

doi:10.3901/JME.2022.17.276

Abstract

Abstract: For meeting diversified optical requirements, planar microlens array (MLA) is gradually developing towards complex structure, for example, microlens units are arranged at irregular intervals. To solve the problem of the difficulty in calculating machining path for those complex MLA, an algorithm for slow tool servo cutting path is proposed. Based on calculation process, the algorithm mainly includes three parts. Firstly, equal arc length and equal angle hybrid discrete algorithm is optimized. Secondly, a general algorithm for computing the Z coordinates of discrete points is proposed. Finally, based on a geometrical model, an algorithm for compensating tool radius in Z-direction is developed. The experimental results show that for conventional MLA, whose microlens units are arranged at regular intervals, the calculation speed and surface error PV value of proposed algorithm are 32.62% higher and 30.77% lower than corresponding results of commercial CAM software for ultra-precision cutting, respectively. For complex planar MLA whose microlens units are arranged at unequal intervals and have various polygon contours, desired MLA is well machined by the cutting path from the algorithm. The research work not only is suitable for fast tool servo, but also provides technical support for the development of complex planar MLA.

Key words: microlens array, complicated pattern, slow tool servo, cutting path, tool nose radius compensation

CLC Number:

TG659

WANG Aibo, LIU Jie, ZHAO Qingliang. Research on Slow Tool Servo Machining of Complicated Planar Microlens Array[J]. Journal of Mechanical Engineering, 2022, 58(17): 276-287.

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