摘要:
Diffractive lenses for vision correction are provided on a lens body having a first diffractive structure for splitting light into two or more diffractive orders to different focal distances or ranges, and a second diffractive structure, referred to as a multiorder diffractive (MOD) structure, for diffracting light at different wavelengths into a plurality of different diffractive orders to a common focal distance or range. In a bifocal application, the first and second diffractive structures in combination define the base power for distance vision correction and add power for near vision correction of the lens. The first and second diffractive structures may be combined on the same surface or located on different surfaces of the lens. The first diffractive structure may have blazed (i.e., sawtooth), sinusoidal, sinusoidal harmonic, square wave, or other shape profile. A sinusoidal harmonic diffractive structure is particularly useful in applications where smooth rather than sharp edges are desirable.
摘要:
A bifocal multiorder diffractive lens is provided having a lens body with one or more first regions having a first multiorder diffractive structure providing near vision correction, and one or more second regions having a second multiorder diffractive structure providing distance vision correction, in which the lens defines an aperture divided between the first and second regions. Such one or more first regions may represent one or more annular rings, or other portion of the lens, and the second region may occupy the portion of the lens aperture outside the first region. The lens body may be provided by a single optical element or multiple optical elements. When multiple optical elements are used, the multiorder diffractive structures may be located along an interior surface of the lens. In other embodiments, a bifocal multiorder diffractive lens is provided by a single or multiple element lens body having a multiorder diffractive structure for distance vision correction and one or more refractive regions to add power for near vision correction, or a single or multiple element lens body shaped for refractive power for distance vision correction and a multiorder diffractive structure for add power for near vision correction. The lens may represent a contact lens, a spectacle lens, or the optic portion of an intraocular implant (IOL). Multiorder diffractive structures may be optimized for performance for photopic and scotopic vision.
摘要:
Diffractive lenses for vision correction are provided on a lens body having a first diffractive structure for splitting light into two or more diffractive orders to different focal distances or ranges, and a second diffractive structure, referred to as a multiorder diffractive (MOD) structure, for diffracting light at different wavelengths into a plurality of different diffractive orders to a common focal distance or range. In a bifocal application, the first and second diffractive structures in combination define the base power for distance vision correction and add power for near vision correction of the lens. The first and second diffractive structures may be combined on the same surface or located on different surfaces of the lens. An optical element, such as a substrate or coating, may be integrated along one or both surfaces of the lens to provide the lens with smooth outer surface(s).
摘要:
A bifocal multiorder diffractive lens is provided having a lens body with one or more first regions having a first multiorder diffractive structure providing near vision correction, and one or more second regions having a second multiorder diffractive structure providing distance vision correction, in which the lens defines an aperture divided between the first and second regions. Such one or more first regions may represent one or more annular rings, or other portion of the lens, and the second region may occupy the portion of the lens aperture outside the first region. The lens body may be provided by a single optical element or multiple optical elements. When multiple optical elements are used, the multiorder diffractive structures may be located along an interior surface of the lens. In other embodiments, a bifocal multiorder diffractive lens is provided by a single or multiple element lens body having a multiorder diffractive structure for distance vision correction and one or more refractive regions to add power for near vision correction, or a single or multiple element lens body shaped for refractive power for distance vision correction and a multiorder diffractive structure for add power for near vision correction. The lens may represent a contact lens, a spectacle lens, or the optic portion of an intraocular implant (IOL). Multiorder diffractive structures may be optimized for performance for photopic and scotopic vision.
摘要:
An multiport, multi-wavelength optical switch having and array of angular beam-directing devices employs an anamorphic optical system that transforms a beam corresponding to a given wavelength of a given multi-wavelength input channel into a beam, at a plane of the angular beam-directing device array, having an elliptical Gaussian-beam waist in the angular-directing direction of the beam-directing device and in the orthogonal direction, with the waist in the angular-direction direction being larger than the waist in the orthogonal direction. Planar and non-planar emitter/receivers for use with the switch are disclosed.
摘要:
An multiport, multi-wavelength optical switch having and array of angular beam-directing devices employs an anamorphic optical system that transforms a beam corresponding to a given wavelength of a given multi-wavelength input channel into a beam, at a plane of the angular beam-directing device array, having an elliptical Gaussian-beam waist in the angular-directing direction of the beam-directing device and in the orthogonal direction, with the waist in the angular-direction being larger than the waist in the orthogonal direction. Planar and non-planar emitter/receivers for use with the switch are disclosed.
摘要:
A diffractive/refractive hybrid lens for use in an optical data storage system as an objective is provided by a convex-plano singlet having a refractive element defined by plano-convex surfaces and a diffractive element defined by a Fresnel zone-like pattern on the plano surface which together provide the total power of the lens. The refractive lens is made of a high index, high dispersion glass so that the curvature and thickness of the refractive lens is minimized while providing a large numerical aperture (at least 0.45) at the expense of increased longitudinal chromatic aberration, which are compensated by the diffractive element and without the need for one or more additional curved surfaces as in low index biaspheric glass objective lenses for chromatic and mono-chromatic aberration reduction, which increases the thickness and curvatures of the lens. The invention enables longitudinal chromatic aberration to be corrected for at least a 10 nm band width around a center wavelength over a 20 nm range, as results when different lasers are used and as laser power varies during optical data storage on an optical data storage device (an optical disk). The thin, light weight low curvature achromat has maximum tolerance for various possible manufacturing errors such as decentering, variations in thickness of the lens, tilt and focal length especially for on-axis field of view less than 2.degree. while providing a very high quality spot (Strehl ratio of at least 0.9.).