Aiming at the requirement of high-precision spectral measurement of transient light source, pulse laser wavelength and spectral resolution in pm order and flash duration in ns-ms order, according to the working principle of the Czerny-Turner spectrometer, a cross-asymmetric optical system of Czerny-Turner spectrometer with a spectral range of 800nm-1800nm is designed. Through the design requirements of resolution and spectral range, the light splitting scheme of scanning grating tower with three gratings spliced is determined. The initial structure calculation includes the calculation of single-shot spectral range, characteristic wavelength and scanning angle, focal length and aperture of collimator, focal length and aperture of focusing mirror. Then, according to the above calculation results, the Zemax optical design software of Zemax Company is used to establish multiple structures to simulate the rotating scanning of grating tower, so as to realize the grating and splitting of spectrum and carry out the simulation optimization of the system. In order to correct the aberration of optical system of spectrometer, x-y polynomial free-forms surface is introduced into the optical system, which is called corrective mirror. The design results show that the optical system of the spectrometer meets the design requirements and has excellent performance. Under the conditions of slit width of 25 μm, grating constant of 0.8333 μm/ line, F Number 4.6, the optical system of the spectrometer can achieve a resolution better than 0.1 nm at a center wavelength of 800nm. This design method is also applicable to the structural design of other wavebands, and has guiding significance for the design of broadband grating spectrometer.
When the field of operation of precision strike missiles is more and more complicated, autonomous seekers will soon encounter serious difficulties, especially with regard to low signature targets and complex scenarios. So the dual-mode sensors combining an imaging sensor with a semi-active laser seeker are conceived to overcome these specific problems. Here the sensors composed a dual field of view mid-infrared thermal imaging camera and a laser range finder have the common optical aperture which produced the minization of seeker construction. The common aperture optical systems for mid-infrared and laser dual-mode guildance have been developed, which could meet the passive middle infrared high-resolution imaging and the active laser high-precision indication and ranging. The optical system had good image quality, and fulfilled the performance requirement of seeker system. The design and expected performance of such a dual-mode optical system will be discussed.
For the realization of target detection and monitoring of a wide range with the unmanned aerial vehicle (UAV), an UAV-based reconnaissance and surveillance system was proposed. The main optical system was consisted of visible camera with narrow field of view (FOV), mid-wave infrared camera (MWIR) and long-wave infrared camera (LWIR). The aperture was shared and the spectrum was disparted in the terminal. The diameter of primary mirror was 170mm. The focal length was 880mm and field of view was 0.86º for visible camera with narrow FOV, the focal length was 880mm and field of view was 0.8º for MWIR camera, the focal length was 220mm and field of view was 3.2º for LWIR camera. Considering the influence of temperature on the imaging quality, a kind of material with good thermal property was used as mirror substrate. The athermalization method was introduced to realize a high image quality in a wide temperature range of -40℃~+65℃. Zoom optical system was adopted in the visible camera with middle FOV and wide FOV, the view of it was 3.4º~34º. The operating distance of laser channel was designed to 20km. The results of the design indicated that this set of optical system could be used for ground target detection and monitoring of a wide range, met user’s requirement.
In this paper, a low-light-level panoramic imaging system was designed based on the domestic second generation semi low-light-level tube. It has a waveband of 0.4 μm to 0.9μm, an effective focal length of 2.43mm, a working F-number of 1.5, and a field of view 30°~100°. Simulation results show that in the entire field of view, the f-θ distortion is less than 6%. The value of the MTF at 24 lp/mm is greater than 0.3. A mechanical structure supporting was designed. The stray light of this imaging system with its mechanical structure supporting was theoretical analyzed by using the software ZEMAX. A actual measurement was also carried out by a France stray light measuring instrument REFLET-180. The actual measurement results match with the theoretical results well in the simulation accuracy that verify the correctness of theoretical analysis and prove the feasibility of system design.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.