摘要:
A method for modifying the refractive index of ocular tissues. The method comprises irradiating select regions of ocular tissue with a visible or near-IR laser. The irradiation results in the formation of structures in the ocular tissue, characterized by a change in refractive index, and which exhibit little or no scattering loss.
摘要:
By adapting femtosecond micromachining approaches developed in hydrogels, we can perform Intra-tissue Refractive Index Shaping (IRIS) in biological tissues. We reduced femtosecond laser pulse energies below the optical breakdown thresholds to create grating patterns that are associated with a change in the refractive index of the tissue. To increase two-photon absorption, we used a two (or more)-photon-absorbing chromophore.
摘要:
A method for modifying the refractive index of ocular tissues. The method comprises irradiating select regions of ocular tissue with a visible or near-IR laser. The irradiation results in the formation of structures in the ocular tissue, characterized by a change in refractive index, and which exhibit little or no scattering loss.
摘要:
A method for providing vision correction to a patient. The method includes: (a) measuring the degree of vision correction needed by the patient and determining the location and shape of refractive structures that need to be positioned within the cornea to partially correct a patient's vision; (b) directing and focusing femtosecond laser pulses in the blue spectral region within the cornea at an intensity high enough to change the refractive index of the cornea within a focal region, but not high enough to damage the cornea or to affect cornea tissue outside of the focal region; and (c) scanning the laser pulses across a volume of the cornea or the lens to provide the focal region with refractive structures in the cornea or the lens. Again, the refractive structures are characterized by a change in refractive index, and exhibit little or no scattering loss.
摘要:
A method for modifying a refractive property of ocular tissue in an eye by creating at least one optically-modified gradient index (GRIN) layer in the corneal stroma and/or the crystalline by continuously scanning a continuous stream of laser pulses having a focal volume from a laser having a known average power along a continuous line having a smoothly changing refractive index within the tissue, and varying either or both of the scan speed and the laser average power during the scan. The method may further involve determining a desired vision correction adjustment, and determining a position, number, and design parameters of gradient index (GRIN) layers to be created within the ocular tissue to provide the desired vision correction.
摘要:
A method for modifying a refractive property of ocular tissue in an eye by creating at least one optically-modified gradient index (GRIN) layer in the corneal stroma and/or the crystalline by continuously scanning a continuous stream of laser pulses having a focal volume from a laser having a known average power along a continuous line having a smoothly changing refractive index within the tissue, and varying either or both of the scan speed and the laser average power during the scan. The method may further involve determining a desired vision correction adjustment, and determining a position, number, and design parameters of gradient index (GRIN) layers to be created within the ocular tissue to provide the desired vision correction.
摘要:
A method for providing vision correction to a patient. The method includes: (a) measuring the degree of vision correction needed by the patient and determining the location and shape of refractive structures that need to be positioned within the cornea to partially correct a patient's vision; (b) directing and focusing femtosecond laser pulses in the blue spectral region within the cornea at an intensity high enough to change the refractive index of the cornea within a focal region, but not high enough to damage the cornea or to affect cornea tissue outside of the focal region; and (c) scanning the laser pulses across a volume of the cornea or the lens to provide the focal region with refractive structures in the cornea or the lens. Again, the refractive structures are characterized by a change in refractive index, and exhibit little or no scattering loss.
摘要:
A method for modifying the refractive index of an optical, hydrogel polymeric material. The method comprises irradiating predetermined regions of an optical, polymeric material with a laser to form refractive structures. To facilitate the formation of the refractive structures the optical, hydrogel polymeric material comprises a photosensitizer. The presence of the photosensitizer permits one to set a scan rate to a value that is at least fifty times greater than a scan rate without the photosensitizer in the material, yet provides similar refractive structures in terms of the observed change in refractive index. Alternatively, the photosensitizer in the polymeric material permits one to set an average laser power to a value that is at least two times less than an average laser power without the photosensitizer in the material, yet provide similar refractive structures.
摘要:
A method for modifying the refractive index of an optical polymeric material. The method comprises continuously irradiating predetermined regions of an optical, polymeric material with femtosecond laser pulses to form a gradient index refractive structure within the material. An optical device includes an optical, polymeric lens material having an anterior surface and posterior surface and an optical axis intersecting the surfaces and at least one laser-modified, GRIN layer disposed between the anterior surface and the posterior surface and arranged along a first axis 45° to 90° to the optical axis, and further characterized by a variation in index of refraction across at least one of at least a portion of the adjacent segments and along each segment.
摘要:
A method for modifying the refractive index of an optical, polymeric material. The method comprises irradiating select regions of the optical, polymeric material with a focused, visible or near-IR laser having a pulse energy from 0.05 nJ to 1000 nJ. The irradiation results in the formation of refractive optical structures, characterized by a change in refractive index, exhibit little or no scattering loss, and exhibit no significant differences in the Raman spectrum with respect to the non-irradiated optical, polymeric material. The method can be used to modify the refractive index of an intraocular lens following the surgical implantation of the intraocular lens in a human eye. The invention is also directed to an optical device comprising refractive optical structures, wherein the refractive structures are characterized by a change in refractive index, exhibit little or no scattering loss, and exhibit no significant differences in the Raman spectrum with respect to the non-irradiated optical, polymeric material.