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Virtuální zobrazení vzdálených objektů dlouhofokálními spojkami a konkávními zrcadly
Rail, Zdeněk; Vápenka, David
2016 - český
Dlouhofokální spojky a konkávní zrcadla mohou sloužit jako optické prvky, úhlově zvětšující rozměry vzdálených objektů podobně jako dalekohledy. Tyto jejich vlastnosti mohly být pravděpodobně používány pozorovateli dávno před objevem dalekohledu. Naše práce přináší optickou analýzu a výsledky astronomických pozorování soustavou dlouhofokální positivní čočky a lidského oka. The longfocal positive lenses and concave mirrors can serve as optical elements increasing the angular dimensions of the distant objects similarly to telescope.\nThese properties could be probably used by ancient observers before the discovery of telescope.\nOur paper brings optical analysis and results of visual astronomical observations with the longfocal positive lens.
Klíčová slova:
Real and virtual imaging; Angular magnification; Ibn al-Haytham; Benjamin of Tudela; Roger Bacon; Giambattista della Porta; Johann Lippershey; Galileo; Kepler; Longfocal lens; Lighthouse on Pharos island; Ancient lenses; Šolc mirror; Camera obscura; Longfocal lens observation
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Virtuální zobrazení vzdálených objektů dlouhofokálními spojkami a konkávními zrcadly
Dlouhofokální spojky a konkávní zrcadla mohou sloužit jako optické prvky, úhlově zvětšující rozměry vzdálených objektů podobně jako dalekohledy. Tyto jejich vlastnosti mohly být pravděpodobně ...
Methodology of camera spectral response measurement
Melich, Radek; Václavík, Jan; Žídek, Karel
2016 - anglický
Spectral response of the camera will be measured using monochromator in conjunction with an integration sphere. Camera without objective will be placed in one port of the integrating sphere and light beam from monochromator will be fed into perpendicular port. Sensor of the camera sensor will be therefore uniformly illuminated by diffused light from monochromator. Proposed FWHM of the monochromator is 15 nm as a trade-off between light intensity provided by monochromator and deformation of spectral characteristic (Picture XY). Diameter of the integrating sphere has to be larger than 100 mm to ensure uniform illumination over sensor area.
Klíčová slova:
Camera spectral response
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Methodology of camera spectral response measurement
Spectral response of the camera will be measured using monochromator in conjunction with an integration sphere. Camera without objective will be placed in one port of the integrating sphere and light ...
Evaluation of selected parameters of a LIBA2000 glass melt according to ISO 12123.
Václavík, Jan
2016 - anglický
Measurement of refractive indices of samples, specifically refractive indicies nd, ne and Abbe numbers for spectral lines d and e. Assesment of refractive index variation, internal spectal transmitance and amount of striae in samples.\n
Klíčová slova:
glass melt; ISO 12123; striae; refractive index; inhomogeneity
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Evaluation of selected parameters of a LIBA2000 glass melt according to ISO 12123.
Measurement of refractive indices of samples, specifically refractive indicies nd, ne and Abbe numbers for spectral lines d and e. Assesment of refractive index variation, internal spectal ...
Device calibration.
Melich, Radek; Václavík, Jan; Žídek, Karel
2016 - anglický
The device has to be calibrated in absolute terms for its brightness response. This will be facilitated by a combination of an integrating sphere and collimating objective. The emitted total light intensity will be controlled by a reference photodiode inside the integrating sphere.
Klíčová slova:
absolute brightness calibration
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Device calibration.
The device has to be calibrated in absolute terms for its brightness response. This will be facilitated by a combination of an integrating sphere and collimating objective. The emitted total light ...
METIS mirror M0 FS
Lédl, Vít; Melich, Radek; Vít, Tomáš
2016 - anglický
Scope of the document is to provide required test results with respect to the structure of M0 mirror, FS version. The mirror has a unique numbering M0-C17-20.
Klíčová slova:
METIS M0 mirror
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
METIS mirror M0 FS
Scope of the document is to provide required test results with respect to the structure of M0 mirror, FS version. The mirror has a unique numbering M0-C17-20.
Black Chromia Plating for the Solar Radiation Absorbers
Brožek, Vlastimil; Březina, Václav; Brom, Petr; Kubatík, Tomáš František; Vilémová, Monika; Mastný, L.; Novák, M.
2016 - anglický
Black chromia layers were produced on copper, zirconium and aluminium substrates. These layers are aimed to serve as solar collectors. Efficiency of the layers during UV-VIS, UV radiation and WSP® plasma torch radiation is described. The chromia layers were prepared by a new procedure, i.e. deposition of ammonium dichromate solution using plasma torch or so called Liquid Precursor Plasma Spraying (LPPS). Solution of ammonium dichromate is fed into plasma stream, where dissociation takes place under temperatures of 4000 K – 25000 K. Up to nanometric oxide particles can be produced; the resulting size is dependent on solution concentration and feeding nozzle diameter. The particles impact on substrate and form coating. Using 2 wt.% to 5 wt.% solution of ammonium dichromate and feeding nozzle of 0.2 mm in diameter is the size of produced chromia particles about 6 µm which results in formation of 2 µm to 3 µm thick coating, i.e. according to the theory an optimal thickness 2.5 um for absorption layers, necessary condition for formation energy traps for IR radiation emitters up to 100°C. Moreover, black chromia coating is a suitable corrosion barrier of metallic substrates. \n\n
Klíčová slova:
Solar collector; black chromia; plasma spraying; ceramic coatings
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Black Chromia Plating for the Solar Radiation Absorbers
Black chromia layers were produced on copper, zirconium and aluminium substrates. These layers are aimed to serve as solar collectors. Efficiency of the layers during UV-VIS, UV radiation and WSP® ...
Black Chromia Coatings on Metal Tubes for the Solar Collectors
Brožek, V.; Mastný, L.; Novák, M.; Vilémová, Monika; Kubatík, Tomáš František
2016 - anglický
This paper describes the results of the first phase of the study preparation, structure and properties of coatings modification of black chromium oxide on copper, aluminium, iron and zirconium tubes for solar collectors. The coatings are prepared by plasma spraying of liquid chromate method which is known as liquid precursor plasma spraying. Coatings have the function of an energy trap for thermal radiation wavelengths of 1 μm – 3 μm i.e. in the IR region. At the same time, the coating increases the corrosion resistance of metal substrates. The nanometric structure and thickness of the coating depend of the feeding distance and the concentration of chromate precursors. For the deposition of nanometric splats of melt chromiumIII oxide, a new type of feeder that injects precursors into the water stabilized thermal plasma produced by the WSP® generator has been\ndeveloped.\n
Klíčová slova:
Solar collector; black chromia; plasma spraying; suspension spraying
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Black Chromia Coatings on Metal Tubes for the Solar Collectors
This paper describes the results of the first phase of the study preparation, structure and properties of coatings modification of black chromium oxide on copper, aluminium, iron and zirconium tubes ...
Spectroscopic Study of Underwater Electrical Discharge Generated by Nanosecond Pulses.
Pongrác, Branislav; Šimek, Milan; Babický, Václav; Člupek, Martin; Lukeš, Petr
2016 - anglický
Underwater electrical discharge generated by high voltage pulses with nanosecond duration (~110 kV amplitude on the needle, ~5 ns duration (FWHM), 1 Hz repetition rate) has been investigated. Time–resolved optical emission spectroscopy showed different emission spectra profile of the ns–pulsed discharge compared to the μs–pulsed discharges investigated previously. Some characteristic peaks typical for water discharges (Hα, OI) were clearly visible in the spectra. In addition, the integral light emission of the discharge was recorded by photomultiplier tube.
Klíčová slova:
nanosecond discharge; water discharge; time-resolved emission spectroscopy
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Spectroscopic Study of Underwater Electrical Discharge Generated by Nanosecond Pulses.
Underwater electrical discharge generated by high voltage pulses with nanosecond duration (~110 kV amplitude on the needle, ~5 ns duration (FWHM), 1 Hz repetition rate) has been investigated. ...
PROBA3 Coronograph System Progress Report
Horodyská, Petra; Melich, Radek
2016 - anglický
The scope of this document is to provide to CSL and ESTEC a progress report of ongoing activities as described in Project Management Plan v1_1. TOPTEC main activities cover realization of coronagraph optical elements, housing for this elements, HDD and the Lyot stop realization. In year 2016, the DM model was finished and delivered and the STM model was competely realized and delivered. Toptec started to prepare the documents for Critical Design Review (CDR).
Klíčová slova:
coronagraph optical elements; housing; HDD; Lyot stop; DM; STM
Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd.
PROBA3 Coronograph System Progress Report
The scope of this document is to provide to CSL and ESTEC a progress report of ongoing activities as described in Project Management Plan v1_1. TOPTEC main activities cover realization of coronagraph ...
METIST mirror M1 FS
Lédl, Vít; Melich, Radek; Vít, Tomáš
2016 - anglický
Scope of the document is to provide required test results with respect to the structure and optical performance of individual optical surfaces of M1 mirror, FS version. The mirror has a unique numbering M1-C20-23.
Klíčová slova:
METIS mirror M1 FS
Plné texty jsou dostupné na vyžádání prostřednictvím repozitáře Akademie věd.
METIST mirror M1 FS
Scope of the document is to provide required test results with respect to the structure and optical performance of individual optical surfaces of M1 mirror, FS version. The mirror has a unique ...
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