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Prisms
Published in Abdul Al-Azzawi, Photonics, 2017
Figure 11.2 illustrates the arrangement of a combination of two right angle prisms. The light beam is incident on the first prism and exits from the second prism. The light beam exiting from the second prism is parallel to the incident light beam at the first prism. In this arrangement, the distance between the incident and the exit beams can be varied. The common application of a two-prism combination is use in a submarine periscope.
All at Sea with User Interfaces: From Evolutionary to Ecological Design for Submarine Combat Systems
Published in Theoretical Issues in Ergonomics Science, 2019
Daniel Fay, Neville A. Stanton, Aaron P. J. Roberts
The activities of the command team are supported by the combat system, which encompasses a wide variety of technology available within the control room. A combat system comprises multiple software subsystems including Sonar, periscope, radar, and command systems such as the Submarine Command System (SMCS: (Dominguez et al. 2006)). Combat systems facilitate management of information about contacts and make such information available to the command team. Systems are partially networked, facilitating data sharing between the Sonar and control room (Emery 2010; Owen et al. 2006). Each software subsystem could also be considered a technical agent in the control room sociotechnical system, as they engage in goal-directed behaviour (providing sonar data, tracking targets), and interact with other agents, both socio (displaying and receiving information) and technical (networked communication). This provides further evidence of control room DSA (Stanton 2016), with technological agents also sharing information to facilitate maintenance of SA.
Analysis and correction of geometrical error-induced pointing errors of a space laser communication APT system
Published in International Journal of Optomechatronics, 2021
Furui Zhang, Ping Ruan, Junfeng Han, Yao Li
Generally, the APT (acquisition, pointing and tracking) system is utilized to control the beam pointing direction. Different APT have different advantages, the periscope-type APT is used in LCT (laser communication terminal) for the excellent astigmatism elimination performance.[5] In Japan’s next-generation LEO (low earth orbit) system, the U-shape frame is utilized in SOTA (small optical transponder).[6] A L-type APT terminal is adopted in the LLST (lunar laser space terminal) system for the advantages of small size and light weight.[7] However, in these APT systems, the pointing error of the optical axis induced by geometrical error is usually ineluctable such as unperpendicularity error of azimuth and elevation axis, rotation error, lens installation error, etc. Many scholars pay attention to geometrical error-induced pointing error in previous studies. Wu et al.[8] analyzed pointing error vary regular of periscope-type APT system azimuth and elevation axes based on geometric optical method. Yan et al.[9] analyzed the pointing error of the theodolite type APT. For the pointing error induced optical energy attenuation, Bai et al.[10] proposed a spot prediction method. For the 45° folding mirror of the periscope-type APT system, Song et al.[11] analyzed the thermal deformation-induced pointing error. Ding et al.[12] studied gravity-induced deformation of the T-type APT system. During the assembling process we need to eliminate the geometrical errors as far as we can, but different errors have different effects on beam pointing accuracy in a different type of APT. In order to assemble the APT system effectively, it is necessary to correct the geometrical errors according to its pointing accuracy sensitivity; however, this question gains little attention in previous studies.