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Year Number of Results
1967 1
1968 2
1969 1
1971 1
1978 1
1989 1
1990 1
1992 1
2005 1
2009 1
2010 1
2013 1
2015 1
2016 1
2019 1
2021 1
2022 1
2024 1

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18 results

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Page 1
Corrector systems for cassegrain telescopes.
Wilson RN. Wilson RN. Appl Opt. 1968 Feb 1;7(2):253-63. doi: 10.1364/AO.7.000253. Appl Opt. 1968. PMID: 20062454
Most modern reflecting telescopes have relative apertures of about f/3 and f/8 for the primary and first secondary foci in accordance with the suggestions of Bowen. The angular field which can be used at the first secondary focus is limited by the size of available plates …
Most modern reflecting telescopes have relative apertures of about f/3 and f/8 for the primary and first secondary foci in accordance with t …
Bessel light beam for a surgical laser focusing telescope-a novel approach.
Hosseini-Saber SMA, A Akhlaghi E, Saber A, Limmer BF, Eichler HJ. Hosseini-Saber SMA, et al. Lasers Med Sci. 2024 Jan 17;39(1):33. doi: 10.1007/s10103-023-03968-y. Lasers Med Sci. 2024. PMID: 38231430
However, in many surgery systems, a large ratio of the laser power is wasted due to the reflection from the mirror of a telescopic system, like a Cassegrain telescope, back to the laser side, which not only decreases the system's efficiency but can also damage the system i …
However, in many surgery systems, a large ratio of the laser power is wasted due to the reflection from the mirror of a telescopic system, l …
Kottamia Faint Imaging Spectro-Polarimeter (KFISP): opto-mechanical design, software control and performance analysis.
Azzam YA, Elnagahy FIY, Ali GB, Essam A, Saad S, Ismail H, Zead I, Ahmed NM, Yoshida M, Kawabata KS, Akitaya H, Shokry A, Hendy YHM, Takey A, Hamed GM, Mack P. Azzam YA, et al. Exp Astron (Dordr). 2022;53(1):45-70. doi: 10.1007/s10686-021-09802-z. Epub 2021 Oct 13. Exp Astron (Dordr). 2022. PMID: 34658528 Free PMC article.
In this paper we describe the Kottamia Faint Imaging Spectro-Polarimeter (KFISP) that has been recently developed and designed to be mounted at the Cassegrain focus of the 1.88 m telescope at Kottamia Astronomical Observatory (KAO), Egypt. ...
In this paper we describe the Kottamia Faint Imaging Spectro-Polarimeter (KFISP) that has been recently developed and designed to be mounted …
Passive focusing techniques for piezoelectric air-coupled ultrasonic transducers.
Gómez Álvarez-Arenas TE, Camacho J, Fritsch C. Gómez Álvarez-Arenas TE, et al. Ultrasonics. 2016 Apr;67:85-93. doi: 10.1016/j.ultras.2016.01.001. Epub 2016 Jan 13. Ultrasonics. 2016. PMID: 26799129
FZP provides a more compact solution and is easy to build, but presents some background noise due to interference of waves diffracted at out of focus regions. By contrast, off-axis parabolic mirrors provide a well defined focus and are free from background noise, al …
FZP provides a more compact solution and is easy to build, but presents some background noise due to interference of waves diffracted at out …
Imaging and image restoration of an on-axis three-mirror Cassegrain system with wavefront coding technology.
Guo X, Dong L, Zhao Y, Jia W, Kong L, Wu Y, Li B. Guo X, et al. Appl Opt. 2015 Apr 1;54(10):2798-805. doi: 10.1364/AO.54.002798. Appl Opt. 2015. PMID: 25967192
According to the theory of WFC, we calculate and optimize the phase mask parameter of the cubic phase mask plate, which is used in an on-axis three-mirror Cassegrain (TMC) telescope system. The simulation analysis and the experimental results indicate that the defocused mo …
According to the theory of WFC, we calculate and optimize the phase mask parameter of the cubic phase mask plate, which is used in an on-axi …
Design and analysis for annular focus antenna with off-axial parabolic and slanting hyperbolic rotating surfaces configuration.
Cao B, Jiang P, Wang J, Mao S, Caiyang W, Qin Y, Yang H. Cao B, et al. Appl Opt. 2019 Feb 20;58(6):1356-1362. doi: 10.1364/AO.58.001356. Appl Opt. 2019. PMID: 30874019
We propose a novel annular focus antenna with an off-axial parabolic primary mirror and slanting hyperbolic secondary mirror. ...In ideal conditions, there is no geometric loss in theory and the transmitting efficiency increases by 24.54% compared with the conventional …
We propose a novel annular focus antenna with an off-axial parabolic primary mirror and slanting hyperbolic secondary mirror. ...In i …
The optical system for the 3.5-m ESO telescope.
Köhler H. Köhler H. Appl Opt. 1968 Feb 1;7(2):241-7. doi: 10.1364/AO.7.000241. Appl Opt. 1968. PMID: 20062451
The optical design of a mirror telescope with a free aperture of 3.5 m is described. Observations can be made in the Cassegrain (RC) focus f/8, in the direct focus f/3, and in the coude focus f/30. ...
The optical design of a mirror telescope with a free aperture of 3.5 m is described. Observations can be made in the Cassegrain (RC) …
Optical design of two spectrographs for the Canada-France-Hawaii telescope.
Morbey CL. Morbey CL. Appl Opt. 1992 May 1;31(13):2291-300. doi: 10.1364/AO.31.002291. Appl Opt. 1992. PMID: 20720893
Optical designs of two new spectrographs for the Canada-France-Hawaii telescope Cassegrain focus are described. Also given is a summary of the design procedure using the Dominion Astrophysical Observatory optical design code OPTESA (optical system optimization by ed …
Optical designs of two new spectrographs for the Canada-France-Hawaii telescope Cassegrain focus are described. Also given is …
Wavefront control of the large optics test and integration site (LOTIS) 6.5m collimator.
West SC, Bailey SH, Burge JH, Cuerden B, Hagen J, Martin HM, Tuell MT. West SC, et al. Appl Opt. 2010 Jun 20;49(18):3522-37. doi: 10.1364/AO.49.003522. Appl Opt. 2010. PMID: 20563205
A variation of the Hartmann test measures slopes by monitoring the reflections from 36 small mirrors bonded to the optical surface of the primary mirror. The Hartmann source and detector are located at the f/15 Cassegrain focus. Initial operation has demonstrated a …
A variation of the Hartmann test measures slopes by monitoring the reflections from 36 small mirrors bonded to the optical surface of the pr …
Model predicts bat pinna ridges focus high frequencies to form narrow sensitivity beams.
Kuc R. Kuc R. J Acoust Soc Am. 2009 May;125(5):3454-9. doi: 10.1121/1.3097500. J Acoust Soc Am. 2009. PMID: 19425684
E. fuscus ridges are modeled as a series of four paraboloidal strips and the tragus is considered to act as a secondary reflecting element analogous to a Cassegrain system. A diffraction grading having the equivalent spacing suggests frequencies above 150 kHz. ...
E. fuscus ridges are modeled as a series of four paraboloidal strips and the tragus is considered to act as a secondary reflecting element a …
18 results