At present, the strategic adjustment of global military has a common trend. With the deepening of the exploration of China's Marine, river and groundwater resources, the military demand of territorial sea sovereignty defense is becoming increasingly urgent. The realization of underwater environment survey, target detection and positioning analysis technology has become an urgent problem to be solved in underwater equipment operation in many fields. The current underwater detection technology is mainly divided into acoustic detection and optical detection. Sound detection has small underwater attenuation, wide detection range and relatively mature technology, but its imaging target identification is difficult, real-time, and is easily subject to Marine noise interference. It is difficult to fully adapt to the needs of many underwater delivery platforms and deep-sea detection operations for high resolution imaging detection, observation and positioning. The underwater photoelectric imaging technology, it has become the necessary equipment for many underwater submersible, underwater operation system and target exploration systems. The underwater laser selected circular polarization imaging system consists of selected circular polarization imaging subsystem, underwater laser radiation source, synchronous timing control subsystem, power supply, integrated display control subsystem and sealing structure. The system mainly adopts the distance selection + polarization laser imaging method, reduces the influence of backscattering on imaging quality through the underwater circular polarization laser imaging system based on distance selection, and establishes the database of the characteristics of underwater circular polarization laser imaging; on this basis, an engineering prototype is built to provide application support for target detection, identification and industrialization.
As a kind of photoelectrical imaging device, infrared thermal imaging system is widely used in the fields of industry,
security, fire control and military etc. Infrared thermal imaging system is mainly used to detect the remote targets in the
night and bad environmental condition. Therefore detection capability of infrared thermal imaging system to targets is
key parameter under these applications. The technical factors and environmental condition affecting detection capability
of infrared thermal imaging system are analyzed in this paper, and the theoretical method is set up on this basis. The
detection capability of infrared thermal imaging system to targets on the sea is analyzed by the method, and compared
with the real test results, the analytical results are proved to be correct.
A method based on Seidel aberration theory to design a four mirror optical system with wide field of view was mentioned in this paper. In this method, Seidel aberration theory was studied, and the technical parameters of the system were got from the demands, then the technical parameters, such as the diameter of entrance pupil and the field of view were substituted into the Seidel aberration equations. Then we solved the equations with additional limit, and got the initial parameters of system, for example the radius of curvature of each mirror. The example in this article was a design of a four mirror system with a field of view of 15°and F number of 5. This example showed that the method based on Seidel aberration theory to design a four mirror optical system with wide field of view is effective and feasible.
Reflective zoom system is widely used in the design of large size, wide spectral, high resolution system due to its great superiority in compacting size, system weight, aperture size, free chromatic aberration and thermo-stability. But for coaxial system, its disadvantage of obstruction renders the FOV (field of view) and light utilization rate unsatisfactory. Thus, to make the secondary and tertiary mirror off-axial is a good choice for optical designers. However, there are two problems in the alignment of off-axis zoom optical system. First, the Seidel aberration theory is not applicable for a system without rotational symmetry. Second, it is hard to control the misalignment status when zoomed. To solve this problem, the vector aberration theory is selected to analyze the off-axis three-mirror zoom system. When small perturbation is applied to the system, coincident with the alignment in reality, the residual aberration varies along with the movement of secondary and tertiary mirror. As the result, aberration character of misalignment three-mirror zoom system is provided, which offers guidance for misalignment determination and makes sure of the normal operation of the zoom system. This paper makes description of our experiment on an off-axis three-mirror zoom system and furnishes the figure of sensitivity in different zoom position. The conclusion may provide a reference to the vector aberration theory study on off-axis three-mirror zoom system and computer aided alignment.
All reflective zoom optical systems have advantages of no color aberration and lightweight which have a wide application prospects in space optical system. All reflective zoom optical systems, which have been designed, all use telephoto construction. And these systems have disadvantages of big obscuration and small field of view. So in order to satisfy of requests the wide spectrum and field of view of space optical system, this paper design a novel all reflective zoom optical system which uses anti-telephoto construction with 3 mirrors. Firstly, using the zoom theory of differential, the initial configuration with 2 zoom ratio was obtained. Then simulating and optimizing the system with Zemax that is software of the optical design, we get a novel all reflective zoom optical system. It has a smaller obscuration and bigger field of view than traditional reflective zoom optical system. At last, the image qualities of this system was evaluated and concluded. And the image qualities of this novel all reflective zoom system is well and the construction of the optical system is reasonable. It can be applied in space optical system.
The traditional zoom systems usually change the spaces between optical components to realize the variable focal lengths. Based on active optics, a new type of reflective active zoom system with four mirrors is proposed, which is different from the traditional zoom system by changing the spaces between optical components1. The new zoom system consists of an afocal front group with three mirrors, and the fourth mirror used for focusing. The relation among the four mirrors is determined by the Pezval condition. The secondary and third are deformable mirrors, contributing to the transition among different focal lengths by the curvature radius variation controlled by the voltage, with the constraints limiting its’ changing rules. According to the designed system characteristics and the practical requirements, based on 3rd-order aberration theory, a set of Seidel aberration coefficient functions are established, with the constraint limitations. Then the initial construction parameters of the optical system can be achieved. The new active zoom system with four mirrors can realize that the zoom rario is 3, the focal lengths vary from 100mm to 300mm, and the field angle of view range is 0.22° ~3.6°, and the wide working band is from the visible to the infrared. At the same time, because of the control flexibility, the active optical zoom system has the potential to be widely applied in remote sensing, life medical and other fields.
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.