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http://dx.doi.org/10.3807/KJOP.2017.28.5.241

Design and Analysis of an Optical System for an Uncooled Thermal-imaging Camera Using a Hybrid Lens  

Ok, Chang-Min (LIG Nex1 Co., Ltd.)
Kong, Hyun-Bae (LIG Nex1 Co., Ltd.)
Park, Hyun-Woo (LIG Nex1 Co., Ltd.)
Publication Information
Korean Journal of Optics and Photonics / v.28, no.5, 2017 , pp. 241-249 More about this Journal
Abstract
This paper presents the design and evaluation of the optical system for an uncooled thermal-imaging camera. The operating wavelength range of this system is from $7.7{\mu}m$ to $12.8{\mu}m$. Through optimization, we have obtained a LWIR (Long Wave Infrared) optical system with a focal length of 5.44 mm, which consists of four aspheric surfaces and two diffractive surfaces. The f-number of the optical system is F/1.2, and its field of view is $90^{\circ}{\times}67.5^{\circ}$. The hybrid lens was used to balance the higher-order aberrations, and its diffraction properties were evaluated by scalar diffraction theory. We calculated the polychromatic integrated diffraction efficiency, and the MTF drop generated by background noise. We have evaluated the thermal compensation of a LWIR fixed optical system, which is optically passively athermalized to maintain MTF performance in the focal depth. In conclusion, these design results are useful for an uncooled thermal-imaging camera.
Keywords
Long wave infrared; Diffractive optics; Passive athermalization;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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