Optical method and system for extended depth of focus
AssigneeXceed Imaging Ltd.
InventorZeev Zalevsky
Life of this patent
Estimating the term…
Abstract
An imaging arrangement and method for extended the depth of focus are provided. The imaging arrangement comprises an imaging lens having a certain affective aperture, and an optical element associated with said imaging lens. The optical element is configured as a phase-affecting, non-diffractive optical element defining a spatially low frequency phase transition. The optical element and the imaging lens define a predetermined pattern formed by spaced-apart substantially optically transparent features of different optical properties. Position of at least one phase transition region of the optical element within the imaging lens plane is determined by at least a dimension of said affective aperture.
Claims30
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and either one of a single-, bi- or multi-focii;
- and at least one phase mask being substantially non diffractive defining, together with said at least one imaging lens of said certain affective aperture, a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions;
- wherein the imaging lens is associated with two of said phase masks applied to the lens at opposite sides thereof.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and either one of a single-, bi- or multi-focii;
- and at least one phase mask being substantially non diffractive defining, together with said at least one imaging lens of said certain affective aperture, a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions;
- the imaging lens assembly being adapted to extend the depth of focus up to about 3 diopters, for said certain affective aperture being in a range of about 1.5-5 mm.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising an array of imaging lenses, each having a certain affective aperture and either one of a single-, bi- or multi-focii, and an array of the phase masks, each imaging lens being associated with the at least one of the phase masks, each of the phase masks being substantially non diffractive defining, together with the respective imaging lens of said certain affective aperture a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and either one of a single-, bi- or multi-focii;
- and at least one phase mask being substantially non diffractive defining, together with said at least one imaging lens of said certain affective aperture, a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions, wherein said phase mask is configured as a pattern in the lens in the form of lens regions made of materials with different refractive indices.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and either one of a single-, bi- or multi-focii;
- and at least one phase mask being substantially non diffractive defining, together with said at least one imaging lens of said certain affective aperture, a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions, wherein said phase mask is configured as a mask formed by an array of said phase transition regions arranged in a spaced-apart relationship being spaced by the optically transparent regions of the imaging lens within the imaging lens plane.
A transparent optical element comprising a phase mask formed by spatially low-frequency phase transition regions, the optical element being adapted for adding a focal depth of about 3 diopters to an imaging lens having about 1.5-5 mm effective aperture.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and being either one of a single-, bi- or multi-focii lens;
- and
- at least one phase mask being substantially non diffractive defining, together with said at least one imaging lens of said certain affective aperture, a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions, wherein the phase mask is configured to maximize a defocused optical transfer function (OTF) of the imaging arrangement by providing the out of focus OTF as much as possible away from zero, the position for N transition regions of the phase mask within the imaging lens plane maximizing the OTF is determined as:
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- values for an providing maximum for minima of an expression for auto correlation of a Coherent Transfer Function (CTF) of the imaging lens, where an equals either 1 or −1, {tilde over (D)}(v) being the CTF of the imaging lens corresponding to out of focus position of an object being imaged and being determined as
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- wherein D is the affective aperture dimension, v is a coordinate of the affective aperture in the CTF plane, and ψ is a phase factor representing a degree of getting out of focus.
An imaging lens assembly having extended depth of focus, the imaging lens assembly comprising:
- at least one imaging lens, the imaging lens having a certain affective aperture and either one of a single-, bi- or multi-focii;
- and at least one phase mask being substantially non diffractive, said phase mask being an optical element attached to the imaging lens and defining together with said imaging lens of said certain affective aperture a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions.
A contact lens configured with extended depth of focus, wherein the contact lens, being either a single-, bi- or multi-focii lens, has a certain affective aperture and carries a substantially non diffractive phase mask, the phase mask being configured by an array of phase transition regions arranged in a spaced-apart relationship being spaced by optically transparent regions of the contact lens within the lens plane, the contact lens of said certain affective aperture together with the phase mask thereby defining a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions.
An implantable eye lens configured with extended depth of focus, wherein the implantable eye lens, being either one of a single-, bi- or multi-focii lens, has a certain affective aperture and carries a substantially non diffractive phase mask, the phase mask being configured by an array of phase transition regions arranged in a spaced-apart relationship being spaced by the optically transparent regions of the implantable lens within the lens plane, the implantable lens of said certain affective aperture together with the phase mask thereby defining a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions.
An imaging lens for correction of astigmatism phenomena, wherein the lens has a certain affective aperture and carries a substantially non diffractive phase mask, the phase mask being configured by an array of phase transition regions arranged in a spaced-apart relationship being spaced by the optically transparent regions of the lens within the lens plane, the lens of said certain affective aperture together with the phase mask thereby defining a predetermined pattern of spaced-apart optically transparent features of different optical properties defining spatially low frequency phase transitions.
Dependencies are inferred from the claim text.