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Design of an 8× Four-group Zoom System without a Moving Group by Considering the Overall Length

  • Received : 2021.12.17
  • Accepted : 2022.01.13
  • Published : 2022.02.25

Abstract

We present a method to count the overall length of the zoom system in an initial design stage. In a zoom-lens design using the concept of the group, it has been very hard to precisely estimate the overall length at all zoom positions through the previous paraxial studies. To solve this difficulty, we introduce Teq as a measure of the total track length in an equivalent zoom system, which can be found from the first order parameters obtained by solving the zoom equations. Among many solutions, the parameters that provide the smallest Teq are selected to construct a compact initial zoom system. Also, to obtain an 8× four-group zoom system without moving groups, tunable polymer lenses (TPLs) have been introduced as a variator and a compensator. The final designed zoom lens has a short overall length of 29.99 mm, even over a wide focal-length range of 4-31 mm, and an f-number of F/3.5 at wide to F/4.5 at tele position, respectively.

Keywords

Acknowledgement

National Research Foundation of Korea (NRF); Korea government (MSIT, No. 2019R1F1A1060065).

References

  1. K. Tanaka, "Paraxial analysis of mechanically compensated zoom lenses. 1: Four-component type," Appl. Opt. 21, 2174-2183 (1982). https://doi.org/10.1364/AO.21.002174
  2. K. Tanaka, "Paraxial analysis of mechanically compensated zoom lenses. 2: Generalization of Yamaji type V," Appl. Opt. 21, 4045-4053 (1982). https://doi.org/10.1364/AO.21.004045
  3. K. Tanaka, "II Paraxial theory in optical design in terms of Gaussian brackets," Prog. Opt. 23, 63-111 (1986). https://doi.org/10.1016/S0079-6638(08)70031-3
  4. K. Tanaka, "Recent development of zoom lenses," Proc. SPIE 3129, 13-22 (1997).
  5. K. Tanaka, "General paraxial analysis of mechanically compensated zoom lenses," Proc. SPIE 3749, 286-287 (1999).
  6. S.-C. Park and W. S. Lee, "Paraxial design method based on an analytic calculation and its application to a three-group inner-focus zoom system," J. Korean Phys. Soc. 64, 1671-1676 (2014). https://doi.org/10.3938/jkps.64.1671
  7. T. G. Kuper and M. P. Rimmer, ''Lens modules in optical design,'' Proc. SPIE 0892, 140-151 (1988).
  8. S.-C. Park and R. R. Shannon, "Zoom lens design using lens module," Opt. Eng. 35, 1668-1676 (1996). https://doi.org/10.1117/1.600742
  9. D. Lee and S.-C. Park, "Design of an 8x four-group innerfocus zoom system using a focus tunable lens," J. Opt. Soc. Korea 20, 283-290 (2016). https://doi.org/10.3807/JOSK.2016.20.2.283
  10. S.-H. Jo and S.-C. Park, "Design and analysis of an 8x four-group zoom system using focus tunable lenses," Opt. Express 26, 13370-13382 (2018). https://doi.org/10.1364/OE.26.013370
  11. R. Peng, J. Chen, and S. Zhuang, "Electrowetting-actuated zoom lens with spherical interface liquid lenses," J. Opt. Soc. Am. 25, 2644-2650 (2008). https://doi.org/10.1364/josaa.25.002644
  12. G. Beadie, M. L. Sandrock, M. J. Wiggins, R. S. Lepkowicz, J. S. Shirk, M. Ponting, Y. Yang, T. Kazmierczak, A. Hiltner, and E. Baer, "Tunable polymer lens," Opt. Express 16, 11847-11857 (2008). https://doi.org/10.1364/OE.16.011847
  13. H. Zappe and C. Duppe, Tunable Micro-Optics, 1st ed., (Cambridge University, Cambridge, UK. 2016).
  14. Optotune Inc., "Focus tunable lens EL-3-10," (Optotune Inc.), https://www.optotune.com/el-3-10-lens (Accessed date: October 2021).
  15. M. Herzberger, "Gaussian optics and Gaussian brackets," J. Opt. Soc. Am. 33, 651-655 (1943). https://doi.org/10.1364/JOSA.33.000651