# 소형 2차원 레이저 스캐너용 F-theta 렌즈 역설계

• Choi, Hae Woon (Dept. of Mechanical and Automotive Engineering, Keimyung Univ.)
• 최해운 (계명대학교 기계자동차공학과)
• Accepted : 2016.11.07
• Published : 2017.03.01
• 15 4

#### Abstract

In this study, a reverse design of the F-theta lens was proposed for a 2D scanner in remote welding applications. The curvature and distance of the lens were set as variables, and the focal length of the lens was set as the marginal ray height. The ZEMAX commercial software was used to perform a simulation with unlimited iterations for the optimization process. The target value was optimized using the internal Merit function with the weight factors of focal length and spot diameter. The number of lenses was four, and the focal length obtained from the results was 135mm that is slightly less than that of the commercial lens, which is set with a focal length of 185 mm. The calculated spot diameters are $1.3{\mu}m$, $6.2{\mu}m$, and $16.1{\mu}m$ for $0^{\circ}$, $12.5^{\circ}$ and $23^{\circ}$ of incident laser beam, respectively. It is expected that an optimized lens design is possible by performing the reverse design of a lens by the ray tracing method.

#### Keywords

Laser Welding;Laser Scanner;Reverse Engineering

#### Acknowledgement

Supported by : 한국연구재단

#### References

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