scholarly journals Optical telescope with 3.75 ◦ field of view and pre-aperture slewing mirror with observation area of 50 ◦ ×120 ◦ for the system of observation of day time asteroids (the SODA project)

2021 ◽  
pp. 60-67
Author(s):  
А.С. Шугаров ◽  
В.Е. Шмагин ◽  
А.И. Буслаева ◽  
Б.М. Шустов
Keyword(s):  
Distinctive Feature ◽  
Field Of View ◽  
Optical Scheme ◽  
Space System ◽  
Optical Telescope ◽  
Advantages And Disadvantages ◽  
Observation Area ◽  
Flat Mirror ◽  
Small Pixel

В работе предложена оптическая схема широкоугольного телескопа с полем зрения 3.75 ◦ и апертурой 30 см для космической системы обнаружения декаметровых астероидов (проект СОДА). Основная отличительная особенность телескопа - наличие предапертурного плоского зеркала, обеспечивающего область наведения 50 ◦ × 120 ◦ , время перенаведения между соседними площадками составит не более 3 с. Предложен современный КМОП детектор с мелким пикселем. В работе представлены области обзора телескопов проекта СОДА из точки Лагранжа L 1 при использовании двух, трех и четырех телескопов, кратко обсуждены преимущества и недостатки каждого из вариантов. We propose an optical scheme of a telescope with a field of view of 3.75 ◦ and 30 cm aperture for the space system for observation of decameter size asteroids (the SODA project). The main distinctive feature of this telescope is a pre-aperture flat mirror that provides an observation area of 50 ◦ ×120 ◦ and a repointing time between the adjacent fields of less than 3 s. A modern CMOS detector with a small pixel is proposed. Observable sky area when using 2, 3 and 4 telescopes are described. The advantages and disadvantages of each option are briefly discussed.

scholarly journals Selective Couplers Based on Multiplexed Volume Holographic Gratings for Waveguide Displays

Photonics ◽  
2021 ◽  
Vol 8 (7) ◽  
pp. 232
Author(s):  
Maria Shishova ◽  
Alexander Zherdev ◽  
Sergey Odinokov ◽  
Vladimir Venediktov ◽  
Dmitrii Lushnikov ◽  
...  
Keyword(s):  
Augmented Reality ◽  
Optical Element ◽  
Field Of View ◽  
Optical Scheme ◽  
Information Display ◽  
Holographic Gratings ◽  
Advantages And Disadvantages ◽  
New Type ◽  
Radiation Conversion ◽  
Angular Field Of View

Diffraction waveguides are widely used in augmented reality devices as information display systems for the introduction of data into the human visual field in order to supplement information about the world around us. This paper formulates the principles of radiation conversion in diffraction waveguides made of photo-thermo-refractive glass on the basis of multiplexed volume holographic gratings, and the advantages and disadvantages of high spectral-angular selectivity are analyzed. In the optical scheme, each of the superimposed volume holographic gratings in the diffraction waveguide forms a corresponding part of the composite angular field of view of the augmented reality device. A proposed mathematical model based on angular multiplexing made it possible to synthesize the diffraction optical element for a new type of diffraction waveguide made from photo-thermo-refractive glass and to create a prototype with an angular resolution of at least 3.0 ± 0.5′, with a brightness change in the image of less than 20% and with a composite angular field of view of 32°.

Impact of Visual Scene Field of View on F-16 Pilot Performance

2007 ◽  
Vol 51 (2) ◽  
pp. 75-79 ◽  
Author(s):  
Jamie L. Estock ◽  
Amy L. Alexander ◽  
Emily M. Stelzer ◽  
Kathryn Baughman
Keyword(s):  
Air Force ◽  
Visual Scene ◽  
Field Of View ◽  
High Fidelity ◽  
Pilot Performance ◽  
Advantages And Disadvantages ◽  
Air Combat ◽  
Standard Training ◽  
The Impact ◽  
Integrated Team

The tremendous expense and inherent dangers of training in the aircraft have led to the increased use of simulators for practicing and maintaining air combat skills; However, the advantages and disadvantages of using high or low-fidelity simulators for such training must be specified. An experiment was conducted to examine the in-simulator performance differences between pilots flying lower-fidelity simulators compared to higher-fidelity simulators. The primary difference between the two simulators is the visual scene field-of-view. Sixteen U.S. Air Force F-16 pilots flew standard training missions as an integrated team of four (a “four-ship”) with two pilots flying in the high-fidelity simulators and two pilots flying in the lower-fidelity simulators. Various subjective and objective measures were collected to assess the pilots' ability to maintain a briefed formation. Overall, the results suggest that pilots who practice four-ship employment in the lower-fidelity simulators can perform at the same level as those who practice in the high-fidelity simulators. Future analyses should be conducted to examine the impact of simulator fidelity on other air combat skills and on training effectiveness.

scholarly journals CONDENSING LENS ON BINOCULAR INDIRECT OPHTHALMOSCOPY AND SLIT-LAMP BIOMICROSCOPY

2019 ◽  
Vol 2 (2) ◽  
Author(s):  
Danang Yoga Wiguna ◽  
Sauli Ari Widjaja ◽  
Wimbo Sasono ◽  
Muhammad Firmansjah ◽  
Ima Yustiarini ◽  
...  
Keyword(s):  
Field Of View ◽  
Fundus Examination ◽  
Portable Instrument ◽  
Fundus Image ◽  
Slit Lamp ◽  
Advantages And Disadvantages ◽  
Illumination System ◽  
Indirect Ophthalmoscopy ◽  
Slit Lamp Biomicroscopy ◽  
Indirect Ophthalmoscope

Condensing lens is a lens used as an auxiliary lens in indirect instruments to examines the fundus. This lens is used with binocular indirect ophthalmoscope and slit-lamp biomicroscope to reach a stereopsis image of fundus. Optical principle of condensing lens is to make the eye in myopic condition, so it can producesa real, aerial, inverted and reversed image. This lens was placed between the instruments and the eye of the patient which located closer to patient’s eye. Optimalized position of the lens can produce a good fundus image. Condensing lens have so many power of dioptre that each power produces different magnification and field of view. High powered lenses produces wider field of view than low powered ones. High powered lens can also used in patient with small dilated pupil and shorter distance of examination. Low powered lenses offer more magnification. Fundus examination with binocular indirect ophthalmoscope and slit-lamp biomicroscope have purpose to produces stereopsis image because of the binocularity system. These two instruments have each advantages and disadvantages. The advantages of binocular indirect ophthalmoscope are a portable instrument, relatively can be used in uncooperative patient and it can be used with scleral indentation to reach more peripheral view of the fundus. Meanwhile slit-lamp biomicroscope has the advantages to offer more magnification and flexible illumination system. With higher powered lens use in biomicroscope, it also give advantages in shorter distance of examination and wider field of view.

scholarly journals PROVISIONING SPECIAL REQUIREMENTS FOR OPTICAL DESIGN OF RIFLESCOPE SYSTEM WITH CHANGEABLE FIELDS

2019 ◽  
Vol 6 (1) ◽  
pp. 67-73
Author(s):  
Dmitry Radostev ◽  
Tatyana Khatsevich
Keyword(s):  
Optical Design ◽  
Field Of View ◽  
Optical Scheme ◽  
Simultaneous Representation ◽  
Sighting Line

A schematic solution of a two-channel optical scheme of the sight, providing simultaneous representation in the field of view of two zones with different magnifications is proposed, while a discrete magnification shift is implemented in the higher magnification zone. A method of organizing the introduction of amendments and reconciliations is proposed, which ensures that when changing the direction of the sighting line in the space of objects, placing an image of the aiming mark in the center of the field of view of each of the zones.

scholarly journals A study of gamma-ray burst afterglows as they first come into view of the SwiftUltraviolet and Optical Telescope

2019 ◽  
Vol 488 (2) ◽  
pp. 2855-2863
Author(s):  
M J Page ◽  
S R Oates ◽  
M De Pasquale ◽  
A A Breeveld ◽  
S W K Emery ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Light Curves ◽  
Field Of View ◽  
Prompt Gamma ◽  
Optical Telescope ◽  
Gamma Ray Burst ◽  
Thick Shells ◽  
Temporal Indices ◽  
Rule Out

ABSTRACT We examine the emission from optically bright gamma-ray burst (GRB) afterglows, as the Ultraviolet and Optical Telescope (UVOT) on the Neil Gehrels Swift Observatory first begins observing, following the slew to target the GRB, while the pointing of the Swift satellite is still settling. We verify the photometric quality of the UVOT settling data using bright stars in the field of view. In the majority of cases, we find no problems with the settling exposure photometry, but in one case, we excise the first second of the exposure to mitigate a spacecraft attitude reconstruction issue, and in a second case, we exclude the first second of the exposure in which the UVOT photocathode voltage appears to be ramping up. Of a sample of 23 afterglows which have peak V magnitudes <16, we find that all are detected in the settling exposures, when Swift arrives on target. For nine of the GRBs, the UVOT settling exposure took place before the conclusion of the prompt gamma-ray emission. Five of these GRBs have well-defined optical peaks after the settling exposures, with rises of >0.5 mag in their optical light curves, and there is a marginal trend for these GRBs to have long T90. Such a trend is expected for thick-shell afterglows, but the temporal indices of the optical rises and the timing of the optical peaks appear to rule out thick shells.

scholarly journals A Novel Scanning Method Applied to New-Style Solar Telescope Based on Autoguiding System

2018 ◽  
Vol 2018 ◽  
pp. 1-13
Author(s):  
Zhi-ming Song ◽  
Zhong-quan Qu
Keyword(s):  
Closed Loop ◽  
Special Structure ◽  
Field Of View ◽  
Optical Telescope ◽  
Fiber Array ◽  
Scanning Method ◽  
Scanning Step ◽  
Disturbance Suppression ◽  
Random Disturbances ◽  
Software And Hardware

To expand field of view (FOV) of telescope, the method of special scanning often is used, but, for some telescopes with special structure in optics and machine, the conventional scanning methods are unsuitable. This paper proposes a novel scanning method based on autoguiding system so as to expand the FOV of fiber array solar optical telescope (FASOT) in possession of the special structure in optics and machine. Meanwhile, corresponding experiments are conducted in the FASOT prototype, FASOT-1B, in order to demonstrate that, for both FASOT and FASOT-1B, the proposed scanning method is feasible. First of all, on the basis of the software and hardware characteristics of FASOT and FASOT-1B, the three key technologies related to the proposed scanning method are described: quickly locating and pointing the first scanning step, the closed-loop controlling of multistep scanning, and the disturbance suppression of every scanning step based on Kalman filter. Afterwards, experiments are conducted and corresponding results show that the proposed scanning method is robust for the random disturbances forced on every scanning step and able to meet the scanning requirement of both FASOT and FASOT-1B .

scholarly journals A New Ocular Micrometer for the MAHIS

1995 ◽  
Vol 167 ◽  
pp. 335-336
Author(s):  
T. R. Kirian ◽  
V. S. Korepanov ◽  
V. M. Grozdilov
Keyword(s):  
Focal Plane ◽  
Ccd Camera ◽  
Optical Scheme ◽  
List Type ◽  
Coherent Light ◽  
Working Model ◽  
Ccd Matrix ◽  
Ocular Micrometer ◽  
Flat Mirror ◽  
Laboratory Investigations

A working model of an ocular micrometer has been designed for the MAHIS (Meridian Automated Horizontal Instrument by Sukcharev). An optical scheme of the micrometer includes the following devices: a)Artificial light marks in the focal plane of the objective. The marks have an increased sharpness and have a stable scale factor under defocusing. An amplitude-phase grid illuminated by coherent light from the second main point of the objective is used to make the marks.b)The observed stars and artificial marks are imaged on the CCD chip by means of an additional objective. This objective also corrects chromatic aberations of the main objective.c)A concentric meniscus is used to compensate for the chromatic refraction of the atmosphere. The meniscus center of curvature coincides with the center of the system's pupil image. In this case the compensation is equal at all points of the field of view.d)The possibility of measuring the normal attitude of the flat mirror relative to the main instrumental plane during each observation is discussed. For these purposes there needs to be a holographic grid on the mirror surface, an artificial zenith or nadir horizon and an autocollimated source of light in the focal plane.e)Laboratory investigations of a working model of a CCD camera are being carried out and the basic software is being developed. This work is planned to be finished in the autumn of 1994. The CCD matrix ISD 011A (NPO “Electron”, St. Petersburg, Russia) 512 × 512 pixels, with pixel size of 16 × 16 mkm is used. The noise is 5 electrons/pixel/sec when the temperature is −40° C (thermoelectric cooler).

scholarly journals Teams Games Tournament (TGT): memadukan unsur competitive dan cooperative dalam rangka peningkatan kualitas pembelajaran PKn

2006 ◽  
Vol 3 (1) ◽  
Author(s):  
Suyato Suyato
Keyword(s):  
Student Achievement ◽  
Distinctive Feature ◽  
Instructional Effectiveness ◽  
Instructional Activity ◽  
Advantages And Disadvantages ◽  
Competitive Model ◽  
Team Game

Many researches has been done in searching the advantages and disadvantages, both Cooperative and Competitive model of teaching, each of them has marry advantages. Accordingly, the rest task of teachers is to take the advantages and eliminate its disadvantages. This article tries to propose Team Game Tournament as a means in integrating cooperative and competitive aspects of instructional activity. With its distinctive feature, TGT can combines both cooperative and competitive spirits of student as a result, hopefully, student' achievement will increase. Implementation of TGT in some right occasion is one of means in increasing instructional effectiveness.

scholarly journals RESEARCH INTO SMELL EMITTED BY CONTAINERS FOR PUBLIC WASTE / KONTEINERIUOSE SURENKAMŲ BUITINIŲ ATLIEKŲ SKLEIDŽIAMO KVAPO TYRIMAI

2012 ◽  
Vol 5 (4) ◽  
pp. 455-461 ◽  
Author(s):  
Tadas Lukauskas ◽  
Eglė Zuokaitė
Keyword(s):  
Distinctive Feature ◽  
Geometric Parameters ◽  
Household Waste ◽  
Air Samples ◽  
Advantages And Disadvantages ◽  
Domestic Activities

Waste is generally accepted as any materials and objects that a holder discards, wants to discard or is required to be discarded. The article deals with the smell of prefabricated containers for household waste produced under normal domestic activities. The paper discusses the advantages and disadvantages of open, shallow and underground Molok containers, installation options and geometric parameters. Research has been conducted referring to air samples taken from three open, three shallow and three underground Molok containers at an outside temperature of 0 °C and depending on the replenishment of containers. The performed analysis has shown that the strongest smell of household waste is detected from completely replenished containers. Open containers have a distinctive feature of releasing a strong smell - in one of those, the odour strength of 119 OUE/m3 has been determined. Santrauka Atliekos visuotinai suprantamos kaip bet kokios medžiagos ir daiktai, kurių turėtojas atsikrato, nori ar privalo atsikratyti. Straipsnyje nagrinėjamas konteineriuose surenkamų buitinių atliekų, susidarančių įprastinėje žmogaus buitinėje veikloje, skleidžiamas kvapas. Aptariami atvirųjų, šachtinių ir požeminių Molok konteinerių privalumai ir trūkumai, įrengimo galimybės, geometriniai parametrai. Tyrimo metu esant 0 °C aplinkos temperatūrai oro mėginiai imti iš trijų atvirųjų buitinių atliekų konteinerių, trijų šachtinio tipo konteinerių ir trijų požeminių Molok konteinerių, atsižvelgiant į konteinerių buitinių atliekų pripildymo būdą. Tyrimais nustatyta, jog stipriausias buitinių atliekų kvapas susidaro konteineriuose, esant visiškam buitinių atliekų pripildymui. Buitinių atliekų skleidžiamo kvapo stiprumu išsiskiria atvirojo tipo konteineriai, iš kurių viename nustatytas net 119 OUE/m3 kvapo stiprumas.

The Research on Joining of Segmented Window-Glass

2017 ◽  
Vol 873 ◽  
pp. 319-323
Author(s):  
Mei Xia Bu ◽  
Jin Song Zhou ◽  
Xin Wang ◽  
Xiao Ying He ◽  
Lei Feng
Keyword(s):  
High Resolution ◽  
Window Glass ◽  
Field Of View ◽  
Large Field ◽  
Military Aircraft ◽  
Optical Window ◽  
Advantages And Disadvantages ◽  
Mechanical Connection ◽  
Section Type ◽  
The Military

There is one project related to high resolution aeronautic camera, which is used in the Military aircraft. In the project, the task requires that the camera's field angle is ±20 degrees. Besides, we there need a window glass for the camera, and the distance between the window-glass and the platform is limited not more than 30mm. That is to say, the aerial camera is required to have a large field of view and small optical window order. To solve this problem, we designed a four-section-type optical window. This paper mainly describes the possible kinds of joining of the glasses used in this four-section-type optical window. There are three kinds of joining mentioned in this paper, such as mechanical connection, joining with adhesive and welding connection. Every kind has its own advantages and disadvantages. After the comprehensive consideration, the paper will use the method of mechanical connection. And this paper will give some guiding significance for the subsequent progress of the project.

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