design variants of a recently developed optical imaging system have been computed for the thermal infrared spectral bands, which offer some advantages for long-range surveillance and astronomy. Only the spherical prim...
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ISBN:
(纸本)0819441554
design variants of a recently developed optical imaging system have been computed for the thermal infrared spectral bands, which offer some advantages for long-range surveillance and astronomy. Only the spherical primary mirror has the fall pupil diameter, all other components being sub-diameter, so scaling is possible up to relatively large pupils. Low-cost fabrication is enabled by the prevalence of spherical optical surfaces. Both MWIR and LWIR spectral transmissions are enabled by the choice of corrector materials, the examples given employing germanium and sapphire for 3.5-5.5 mum and germanium and zinc selenide for 3.5-5.5[mum and 8-12mum passbands. Diffraction at these wavelengths is the main contributor to resolution constraints, so high numerical aperture values are preferred to enable a better match of blur spot diameter to generally available pixel dimensions. The systems described can routinely be designed to have speeds of f/0.8 or faster, while maintaining diffraction-limited performance over useful angular fields. Because the new design system employs a relayed catadioptric, it is possible to make the aperture stop of the system coincident with the window of the detector cryostat, enabling precise radiometric geometry. The central obscuration provides a convenient location for a calibration source, and both this and a mask for secondary spider supports can be included within the detector cold screen structure. Dual-band operation could be enabled by inclusion of a spectral beam splitter prior to a dual relay/imager system.
Some results obtained in the realization of compact relay systems design are presented. Four optical configurations have been analyzed. Two symmetrical schemes were examined having field Smith's lenses for a image...
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ISBN:
(纸本)0819432652
Some results obtained in the realization of compact relay systems design are presented. Four optical configurations have been analyzed. Two symmetrical schemes were examined having field Smith's lenses for a image scaling of-ix. The achieved numerical aperture is up to 0.35 and the MTFs curves are at 40 cycles1/mm for a contrast ratio of 0.2. The third design has a large field of 40 mm but its F-number is about F/4.5. The last relay system is unsymmetrical. The scaling is 2x and the image field exceeds 50 mm. The aberration balancing results and the optical systems performance are illustrated.
The 'concentric-aplanatic' method used for lens design is described in many papers. While many shapes and forms of these lenses have been shown, performance evaluation of these lenses has never been published....
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ISBN:
(纸本)0819403954
The 'concentric-aplanatic' method used for lens design is described in many papers. While many shapes and forms of these lenses have been shown, performance evaluation of these lenses has never been published. How good is the method? Can one designoptical systems using this technique that have acceptable image quality? This paper will deal step by step with these questions, both from first principles and by the basis of third order theory. Performance evaluations will be given for the lenses designed.
Cryogenic optical systems are often mounted in vacuum cryostat. An interesting concern in the mechanical design is how to maintain the stability of the line of sight (LOS) of the cryogenic optical system when it is co...
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ISBN:
(纸本)0819463671
Cryogenic optical systems are often mounted in vacuum cryostat. An interesting concern in the mechanical design is how to maintain the stability of the line of sight (LOS) of the cryogenic optical system when it is cooled down to very low temperature. To investigate this problem an experimental cryogenic optical system, its mounting structure, and a cryostat were designed and fabricated. After assembling them together, a test experiment for measuring the LOS drift was carried out. Finally, the test results will be presented in this paper.
A 1:1 Offner mirror system is modified to work as a grating spectrometer for the infrared by placing a grating on the secondary convex mirror of the system. Slight adjustment of the configuration combined with tilt of...
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Photonic switching systems image arrays of sources onto arrays of detectors and modulators. Even this simple functionality poses serious challenges for the optical engineer. Image quality must be excellent because the...
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ISBN:
(纸本)0819422517
Photonic switching systems image arrays of sources onto arrays of detectors and modulators. Even this simple functionality poses serious challenges for the optical engineer. Image quality must be excellent because the large modulator bandwidth demands small modulator size. Magnification and distortion must be precisely corrected for the spot array to fit onto the detector array. The system must be extraordinarily stable for the spots to stay on the detector array. For these reasons, photonic switching systems have traditionally been mounted on vibration isolated optical tables. This paper will describe our newest system, which is mounted in a standard electronics frame. Experimental results and design methodologies will be discussed.
The basis of this work is a modification of the modern design of surgical binoculars based on substitution of mineral glasses with polymer lenses. Aberration analyses of the proposed systems is shown.
ISBN:
(纸本)9781510612082;9781510612075
The basis of this work is a modification of the modern design of surgical binoculars based on substitution of mineral glasses with polymer lenses. Aberration analyses of the proposed systems is shown.
An optically routed gate array(OPGA) is used to implement a simple game of TIC TAC TOE to demonstrate the utility of electrooptical circuits which embody user input, display and logic functions in a single device. Pro...
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ISBN:
(纸本)0819422517
An optically routed gate array(OPGA) is used to implement a simple game of TIC TAC TOE to demonstrate the utility of electrooptical circuits which embody user input, display and logic functions in a single device. Progress on routing techniques layout and logic simulation will be presented.
An alternative to Damped Least Squares (DLS) optimization of lens systems is described that involves Generalized Simulated Annealing (GSA) techniques in conjunction with DLS. The resultant method can often overcome lo...
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In the article some methods for processing the information contained in a database are offered with the purpose of extraction of the knowledge, the experience and the intuition of the designers, coded in the database....
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ISBN:
(数字)9781510602861
ISBN:
(纸本)9781510602854;9781510602861
In the article some methods for processing the information contained in a database are offered with the purpose of extraction of the knowledge, the experience and the intuition of the designers, coded in the database. It gives much attention to the methods for determinating limit potential image quality of optical systems of various complexities.
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