Showing papers on "Apochromat published in 1983"
TL;DR: Split beams of varying separations from a helium-neon laser were directed through the crystalline lenses of a number of vertebrates to indicate the extent to which the refractive index variation of the lens and lens shape control spherical aberration.
110 citations
TL;DR: The calculated chromatic aberration of the human eye is greater than values reported earlier, because of the exaggerated dispersion of the lens at short wavelengths.
73 citations
TL;DR: Thicknesses and curvatures of the optic components of enucleated eyes were determined in both transverse and sagittal planes, finding that the cornea and lens surfaces are closer approximations to spheres than are the retina and choroid.
55 citations
Patent•
05 Dec 1983TL;DR: A progressive multifocal ophthalmic lens as discussed by the authors includes a lens surface having a far vision view, a near vision viewing, and an intermediate vision viewing zone disposed therebetween, and a prism having a base is added to the lens.
Abstract: A progressive multifocal ophthalmic lens. The lens includes a lens surface having a far vision viewing, a near vision viewing zone and an intermediate vision viewing zone disposed therebetween. A prism having a base is added to the lens. The base lies in the direction of 90° to the lens surface. The prism is added in order to improve chromatic aberration and not to remedy squint.
33 citations
TL;DR: A negative lens cemented to a shortened GRIN relay lens can simultaneously correct axial and lateral chromatic aberrations with commercially available components, which reduces the requirements for mechanical centration better than do color correctors that are incorporated into the ocular design.
Abstract: A gradient-index (GRIN) endoscope can be constructed by substituting for the usual objective and relay sections suitable cylindrical index-distribution rod lenses. Currently available GRIN lenses exhibit large amounts of chromatic aberration. Axial color arises mostly from the relay lens, while lateral color is due to the objective lens. A negative lens cemented to a shortened GRIN relay lens can simultaneously correct axial and lateral chromatic aberrations with commercially available components. This correction system reduces the requirements for mechanical centration better than do color correctors that are incorporated into the ocular design. Monochromatic aberrations are also considered.
22 citations
TL;DR: This paper measured the ultraviolet dispersion of several microscope objectives and found that all of them are limited by axial chromatic aberration when used for polychromatic exposure of photoresist.
Abstract: We have measured the ultraviolet dispersion of several microscope objectives and we find that all of them are limited by axial chromatic aberration when used for polychromatic exposure of photoresist. We show how to measure and correct for the ultraviolet focus shift, and estimate the corrected resolution. Certain lenses are able to produce micron features over millimeter fields.
12 citations
TL;DR: In this paper, an illustrative example is given of how the chromatic aberration of a three aspherical plate corrector for prime focus may be reduced greatly as the relative positions of the three plates are changed for various wavelength bands.
Abstract: In this paper, an illustrative example is given of how the chromatic aberration of a three aspherical plate corrector for prime focus may be reduced greatly as the relative positions of the three plates are changed for various wavelength bands. The conclusion drawn from this is that the chromatic aberration of an optical system can be improved if each of those elements which can be moved are adjusted for different wavelength bands. This method may also be used to reduce the aberrations caused by temperature variations.
3 citations
2 citations
26 Oct 1983
TL;DR: In this article, the air gap between adjacent lenses can be regarded as an "air lens" imbedded in glass, and the resulting new designs, when certain of the original air lenses are removed, often have distinctly better aberration correction, or other features that are desirable, such as a different system length.
Abstract: The air gap between adjacent lenses can be regarded as an "air lens" imbedded in glass. In many situations these air lenses, in glass, have glass lens equivalents, in air. The resulting new designs, when certain of the original air lenses are removed, often have distinctly better aberration correction, or other features that are desirable, such as a different system length. This transformation is easiest when the air lens that is to be removed has a nearly concentric meniscus shape. The glass lens equivalent then has about the same shape, and is located outside the two lenses bounding the air gap. The latter disappears and the two adjacent lenses combine into a single lens. Examples of this transformation, and the resulting benefits, are shown for an air-spaced aplanatic doublet, a Cooke triplet, and a Houghton catadioptric system. This point of view is very useful for generating new design variations from well-known types.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
1 citations
08 Nov 1983
TL;DR: In this article, the authors proposed a corrector lens design which will provide a 0.5 degree field of good definition from 134nm to 280nm at the Ritchey-Chretien focus of the F/2-F/15 Starlab 1-metre telescope.
Abstract: Parameters are given for a corrector lens design which will provide a 0.5 degree field of good definition from 134nm to 280nm at the Ritchey-Chretien focus of the F/2-F/15 Starlab 1-metre telescope. The optimization includes the window of the detector which is aspherized on the outside but not on the inside where the photocathode is deposited. The 130 mm diameter detector is preceded by two lenses, the first of which is convex-plano. Because this element has a flat surface it can be interchanged with other elements to either compensate for the chromatic aberration of filters (by making the lens thinner), and/or to provide dispersion for multi-object slitless spectroscopy. In the latter case, the interchanged element is wedged and has a course transmission grating deposited on the flat side. This combination of grating and lens is referred to as a grens.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
1 citations