Wyniki wyszukiwania - Biblioteka Nauki

Ten serwis zostanie wyłączony 2025-02-11.

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 5

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: aberracja

Sortuj według:

Ogranicz wyniki do:

Świat przez zero. Czy i jak soczewki okularowe o mocy zero wpływają na widzenie?

100%

Pniewski J.

2016

tom Nr 2

62--63

Fourier transform holographic storage

88%

Andruchów A.

Optica Applicata

2004

tom Vol. 34, nr 4

635-645

Holographic optical elements for Fourier transform (HOE-FT) used in the optical memory system are considered in this paper. The determination of the optimal page composer capacity allows for the appropriate choice of the diameter of HOE-FT as well as the size of a hologram recorded in the fotorefractive crystal LiNbO3:Fe, with the help of two different wavelengths of the laser light beam. When the interfering field is recorded in the HOE-FT structures, properties of the recorded spectru are established. The proper choice of the phase function coefficients allows aberration to be corrected on the basis of spotdiagrams obtained.

Use of computer algebra system for recalculation of the fifth-order aberrations of GRIN media.

75%

Magiera L.

Optica Applicata

2001

tom Vol. 31, nr 3

545-551

The methodology of calculation of the fifth-order aberrations of gradient-index (GRIN) media by application of computer symbolic calculations (computer algebra) is presented. The software package applied was REDUCE. The results obtained enabled us to correct the results known from the literature. The designed computer program has also been added. A special computer program has also been designed.

Aberracje obiektywów hybrydowych

75%

Zając M.

Prace Naukowe Instytutu Fizyki Politechniki Wrocławskiej. Monografie

2005

tom Vol. 37, nr 26

1-130

Monografia jest poświęcona badaniu jakości odwzorowania obiektywów hybrydowych, czyli takich, w których jednym ze składników jest struktura dyfrakcyjna. Punktem wyjścia są wzory opisujące III-rzędowe aberracje Seidela powierzchni refrakcyjno-dyfrakcyjnej. Na ich podstawie wyprowadzono warunki, konieczne do uzyskania korekcji chromatyzmu na poziomie achromatu, apochromatu i quasi-superachromatu, oraz warunki zapewniające korekcję aberracji sferycznej. Analizowano także możliwości skorygowania aberracji polowych: komy, astygmatyzmu i krzywizny pola. Ponieważ niektóre zależności analityczne są bardzo złożone, w wielu przypadkach posłużono się analizą numeryczną. Rozważania teoretyczno-numeryczne zilustrowano znaczną liczbą przykładów, to znaczy projektów konkretnych obiektywów hybrydowych o zadanej korekcji. Jeden z rozdziałów pracy dotyczy możliwości zaprojektowania hybrydowej soczewki okularowej.

The aim of any optical knaging system is to transform the wave originating from point object into the image wave of nearly spherical wavefront. In particular, a hybrid lens and a hybrid objectiye are examples of opitical knaging systems. One of their elements, apart from classic refractive lenses, is a diffractive element having the form of a set of concentric fringes deposited on one of the refractive surfaces. The Abbe number, the value of which substantially differs from that for typical optical glasess, can be ascribed to the diffractive element. Thanks to that it is possible to design hybrid imaging systems of corrected chromacie aberration. For hybrid lens it is achromatic correetion, while for hybrid objective apochromatic and superachromatic correetions (however, in slightly limited spectral waverange) are possible. The deviation of an image wavefront from ideał sphere indicates the imaging aberrations. The most common description of abberations includes Seidel expansion in which particular 3rd order coefficients stand for spherical aberration, coma, astigmatism and field curvature as well as for distortion. In this monograph, these coefficients for diffractive surface, hybrid lens and hybrid objective (in both cases: compact one and with two elements separated by an aerial gap) are given. Using these formulas achromatic hybrid lenses with corrected spherical aberration and coma as well as hybrid lenses with corrected astigmatism or field curvature are designed. Such lenses can be used in spectacle opties. Hybrid objectives offer morę possibilities of aberration correetion. It is possible to design plan-apochromatic objectives and superachromatic objectives with flat field or free from astigmatism. Examples of such objectives are presented in the monograph.

Focusing large-aperture beams generated by high-peak-power lasers

51%

Jabłoński S. , Badziak J.

Optica Applicata

2001

tom Vol. 31, nr 3

625-634

The properties of focusing large-aperture fight beams of parameters typical of the beams produced by picosecond terawatt lasers are analysed numerically with the use of 3-D computer code based on Fresnel-Kirchhoff integral formula. It is shown that, contrary to the case of small-aperture Gaussian-like beams, a peak intensity of light in the focus is a non-monotonic function of f/D with a local maximum at moderate f/D values (5 [left angle bracket]or= f/D [left angle bracket]or= 10), where f is the focal length and D is the aperture of a focusing system. For low f/D values (f/D [left angle bracket] 3) more than 80% of laser energy is scattered after focusing in a low-intensity large-dimension aureole round the central peak of focal intensity distribution. The amount of the scattered energy can be significantly decreased by an increase of f/D, and, as a result, the moderate values of this ratio seem to be optimum for most laser-target experiments. The above features appear for both spherical and aspherical focusing systems.