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 Hobby-Eberly Telescope uses a ii-meter diameter F/1.45 segmented spherical primary mirror. A spherical mirror of this size generates large amounts of spherical aberration. To be used successfully in a tilted optic...
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ISBN:
(纸本)0819432652
The Hobby-Eberly Telescope uses a ii-meter diameter F/1.45 segmented spherical primary mirror. A spherical mirror of this size generates large amounts of spherical aberration. To be used successfully in a tilted optical Arecibo type telescope, the spherical aberration needs to be corrected. This means that tracking of astronomical targets is achieved through moving a tracker optical package which imposes somewhat severe packaging constraints. Given these packaging constraints, novel methods must be employed to correct the aberrations with the Spherical Aberration Corrector contained in the moving hacker optical package. The paper reviews the pertinent requirements, constraints and the resultant design of the Hobby-Eberly Telescope Four Mirror Spherical Aberration Corrector.
The double expansion of the wavefront deformation in Zernike polynomials over the pupil and the field-of-view coordinates is a powerful tool for lens design, testing, and alignment. It provides a compact description o...
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ISBN:
(纸本)0819432652
The double expansion of the wavefront deformation in Zernike polynomials over the pupil and the field-of-view coordinates is a powerful tool for lens design, testing, and alignment. It provides a compact description of the wavefront deformation of perturbed and unobscued optical systems over the field-of-view. The integral of the mean-square wavefront deformation over the field-of-view is simply the sum of the products of the norms of the polynomials and the squared global coefficients. Eight or ten global coefficients can provide a comprehensive centered system description. Only fourteen main additional global coefficients is sufficient for the description of perturbed and unobscured optical systems.
Non-imaging integrators which can be used for laser beam homogenization in materials processing with excimer laser radiation are analysed with regards to geometrical and statistical optics. A model for the transversal...
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ISBN:
(纸本)0819432652
Non-imaging integrators which can be used for laser beam homogenization in materials processing with excimer laser radiation are analysed with regards to geometrical and statistical optics. A model for the transversal degree of coherence of the laser radiation is presented in order to estimate the performance of the integrating devices for the partially coherent excimer laser radiation. This is necessary for a more relevant design of those elements than a design by geometric optical means only. The concept of non-imaging integrators is enhanced by separating the multifaceted element from the focusing lens. This separation provides more flexibility in the processing distance of the optical system. A further enhancement is the combination of such a system with an imaging lens in order to create a system which produces a top hat fluence distribution with variable size for materials processing applications.
An original method to enable the exact solution for the noncemented two-lens objective by means of any number of simultaneous non-linear equations is described. The method is limited to spherical surfaces without dece...
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ISBN:
(纸本)0819432652
An original method to enable the exact solution for the noncemented two-lens objective by means of any number of simultaneous non-linear equations is described. The method is limited to spherical surfaces without decentrations. Separations and refractive indices of glasses are fixed. Ail curvatures of surfaces are indirectly determined in the final stage. The typical meridional aperture aberrations deal with aplanatic and achromatic conditions. Essence of the method relies on formulation functions which contain trigonometric expressions and are nested up to certain depth. The method uses the advanced professional mathematical software which is indispensable for serving the non-linear system of equations. Numerical examples confirm the helpfulness of the method.
We describe the features of the optical system for Terrestrial Planet Finder, a space-based, cryogenic (35 K) interferometer for direct detection of Earth-type planets around nearby stars. Destructive interference in ...
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ISBN:
(纸本)0819432652
We describe the features of the optical system for Terrestrial Planet Finder, a space-based, cryogenic (35 K) interferometer for direct detection of Earth-type planets around nearby stars. Destructive interference in a stellar interferometer suppresses stellar glare by a factor of several thousand or more, and phase chopping distinguishes planet light from symmetric backgrounds. The mid-infrared (7-20 mu m) is favorable for detecting planetary emission relative to that from the star, and this spectral region also offers important molecular signatures indicative of key atmospheric gases.
Ball Aerospace is building the Cryogenic Telescope Assembly (CTA) for the Space InfraRed Telescope Facility (SIRTF) project and stray light control is a critical part of this effort. The heliocentric orbit where the S...
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ISBN:
(纸本)0819432652
Ball Aerospace is building the Cryogenic Telescope Assembly (CTA) for the Space InfraRed Telescope Facility (SIRTF) project and stray light control is a critical part of this effort. The heliocentric orbit where the Sun is never allowed to illuminate the CTA and the Earth is relatively far away is a key feature for stray light control. Mirror and paint BRDFs were measured at various SIRTF wavelengths in order to provide inputs for the stray light models. Stray light from telescope self emission, a distant point source, and the galaxy were analyzed. The design ensures that stray light will be less than 21% of the celestial background at all SIRTF wavelengths.
We have examined the main constraints on the design of single-channel, high-capacity soliton communication systems. Ln the average soliton regime, the Gordon-Haus timing jitter limits the bit rate to less than 7 Gb/s ...
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ISBN:
(纸本)0819432652
We have examined the main constraints on the design of single-channel, high-capacity soliton communication systems. Ln the average soliton regime, the Gordon-Haus timing jitter limits the bit rate to less than 7 Gb/s for transoceanic fiber links, while for shorter transmission distances the main limitation is fiber perturbations arising from discrete in-line amplification. The use of dispersion-decreasing fibers and of periodic optical, phase conjugation for jitter control can increase significantly the capacity of soliton communication systems. We found that the third-order dispersion assumes a prominent role in this case. Reducing this effect sufficiently, the main constraint becomes the soliton-soliton interactions and bit rates superior to 110 Gb/s can be achieved for amplifier spacings less than 80 km. For higher amplifier spacings the bit rate is limited by the Raman induced timing jitter.
In this work, modeling along with associate experiments of the broad-area laser with an external optical cavity which employs a mode-selecting mirror has been conducted to study the effects of optical feedback on the ...
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ISBN:
(纸本)0819432652
In this work, modeling along with associate experiments of the broad-area laser with an external optical cavity which employs a mode-selecting mirror has been conducted to study the effects of optical feedback on the filamentation and mode control of broad-area semiconductor lasers. By using split-step FFT algorithm in a propagation model, mode profiles of the broad-area lasers with a spherical cavity are simulated in detail, the simulation results agree very well with experimental measurements and verify the validity of the simulation model. Mode control of broad-area semiconductor lasers has also been studies through employing the same simulation model and associates experiments have also been conducted. The results will be presented in this paper.
Bi-AGRIN cemented doublets, super corrected for zero axial color, spherical aberration and sphero-chromatism (we will call them spherochromats) can show polychromatic performance in the range of 0.004 waves PV or bett...
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ISBN:
(纸本)0819432652
Bi-AGRIN cemented doublets, super corrected for zero axial color, spherical aberration and sphero-chromatism (we will call them spherochromats) can show polychromatic performance in the range of 0.004 waves PV or better at the red and blue wavelengths for speeds up to F/2, (0.06 waves PV of F/1.5). These doublets are comprised of two elements of axial gradient index glass. The crown and flint elements are each designed with separate and distinct gradient glass lines, giving each element an axial gradient in refractive index and dispersion(1). This paper examines one design and its performance sensitivity to dispersion modeling via the Buchdahl and Sellmeier dispersion equations.
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