| With the development of infrared QWIP detector technology,we can use one detector to respond to the MWIR and LWIR infrared radiation simultaneously.This technology has necessitated the further development of dual band optics in order to exploit this detection capability.This technology generates the need for optics that will image both the MWIR and LWIR at the same image plane without refocus,and with sufficient image quality.The dual band infrared system compared with the single band system,which can get much more comprehensive information from the spectrum.The capability make the dual band system had a un-substitute particularity in the military affairs in modern times.Researching and exploiting the dual band system has an importance for theory research nor for practice application.This paper mainly include the following content:1)The principle of the dual band triple field optical system are researched;harmonic diffractive element and selection of optical materials are introduced;The challenge lies with the very broad spectral band,the different partial dispersions of materials in the MWIR and LWIR are calculated in list,the dual band achromatic theory is also discussed in this paper.2)Based on MWIR and LWIR dual QWIP detector,an dual-band infrared triple-field optical system in the form of secondary imaging is designed,the aberrations and tolerances of the system are analyzed.The thermal effects in the dual band are also discussed.3)it is this key assembly of the dual band system design is addressed in this paper.Based on the mode of the field switch and the result of athermalization as well as the focus value,the servo drive control circuit is designed here.Harmonic diffractive lenses were ably utilized to re-modify the dual band system,a much more compact dual band system was designed which had the same parameter as the refract system.The successful re-modification validated the particular advantage of the harmonic diffractive lens in the design of dual band systems. |
PDF Full Text Request