Design of a freeform, dual fields-of-view, dual focal lengths, off-axis three-mirror imaging system with a point-by-point construction-iteration process
In this Letter, we propose a novel configuration and design method of freeform, dual fields-of-view (FOVs), dual focal lengths, off-axis three-mirror zoom imaging systems. The switch of the two zooms is achieved by rotating a single mirror element. The design of a freeform, dual focal lengths zoom system is realized by a point-by-point design approach for the first time to our knowledge. This method enables the direct design of freeform surfaces from initial planes using given system specifications and configuration, and the designed system can be taken as a good starting point for further optimization. A freeform, dual FOVs, dual focal lengths, off-axis three-mirror zoom system is demonstrated. The F-numbers of the two zooms are 2 and 2.4. The dual FOVs are 3°×3° and 2.5°×2.5°. After final optimization, both of the zooms achieve high performances.
Jun Zhu：State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
and Guofan Jin：State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
【1】T. Zhang, Y. Wang, and J. Chang, Chin. Opt. Lett. 8, 701 (2010).
【2】J. Chang, Y. Wang, T. Zhang, M. Talha, Z. Wang, and H. Yang, Proc. SPIE 6342, 63421Q (2006).
【3】C. Kuo, C. Lin, and C. Han, Appl. Opt. 49, 3691 (2002).
【4】M. N. Akram, and M. H. Asghar, Appl. Opt. 42, 2312 (2003).
【5】X. Wang, M. Jiao, and B. Yang, Proc. SPIE 7383, 738350 (2009).
【6】R. S. Kebo, “Dual band/Dual FOV infrared telescope,” U.S. Patent 4,989,962 (1991).
【7】J. M. Rodgers, Proc. SPIE 4832, 33 (2002).
【10】G. Xie, J. Chang, J. Zhou, K. Zhang, and X. Wang, Proc. SPIE 9618, 96180O (2015).
【11】F. Fang, X. Zhang, A. Weckenmann, G. Zhang, and C. Evans, CIRP Ann. 62, 823 (2013).
【12】F. Zhang, Chin. Opt. Lett. 13, S12202 (2015).
【13】D. Cheng, Y. Wang, and H. Hua, Proc. SPIE 7849, 78490Q (2010).
【14】R. A. Hicks, Opt. Lett. 33, 1672 (2008).
【15】G. D. Wassermann, and E. Wolf, Proc. Phys. Soc. B 62, 2 (1949).
【16】J. C. Mi?ano, P. Benítez, W. Lin, J. Infante, F. Mu?oz, and A. Santamaría, Opt. Express 17, 24036 (2009).
【17】F. Duerr, P. Benítez, J. C. Mi?ano, Y. Meuret, and H. Thienpont, Opt. Express 20, 10839 (2012).
【18】Y. Nie, H. Thienpont, and F. Duerr, Opt. Express 23, 34042 (2015).
【19】T. Yang, J. Zhu, X. Wu, and G. Jin, Opt. Express 23, 10233 (2015).
【20】J. Zhu, W. Hou, X. Zhang, and G. Jin, J. Opt. 17, 015605 (2015).
【21】T. Yang, J. Zhu, W. Hou, and G. Jin, Opt. Express 22, 9193 (2014).
【22】J. Zhu, X. Wu, T. Yang, and G. Jin, J. Opt. Soc. Am. A 31, 2401 (2014).
Tong Yang, Jun Zhu, and Guofan Jin, "Design of a freeform, dual fields-of-view, dual focal lengths, off-axis three-mirror imaging system with a point-by-point construction-iteration process," Chinese Optics Letters 14(10), 100801 (2016)