Larry Thibos - Academia.edu (original) (raw)
Papers by Larry Thibos
Ophthalmic and Visual Optics
The optical apparatus of the eye presents a low-pass spatial filter to the front end of the visua... more The optical apparatus of the eye presents a low-pass spatial filter to the front end of the visual system which is a potential limiting factor for any visual task. In the well-focused eye, chromatic aberration and diffraction are thought to be the major optical factors limiting vision.1-3 Recent evidence indicates that ocular chromatic aberration can significantly reduce image contrast, resulting in loss of contrast sensitivity and visual acuity, and may also inject large artifacts into the retinal image of colored visual targets.4,5 Such problems are likely to be exacerbated by the use of achromatizing lenses6 or other optical apparatus such as clinical test instrumentation7 which may shift the eye's achromatic axis away from the fovea, thus exposing central vision to transverse aberration from which it is normally protected.8 Consequently, it is important to have available an accurate, mathematically tractable model of ocular chromatic aberration to help gauge the potential ma...
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Journal of the Optical Society of America, Mar 12, 2019
Starbursts seen around small bright lights at night have been attributed to optical scatter, diff... more Starbursts seen around small bright lights at night have been attributed to optical scatter, diffraction, or aberrations. We manipulated pupil aperture and aberrations to investigate the entopic appearance of perceived starbursts. The impact of circular, annular, and wedge-shaped pupil apertures, and spherical aberration sign and magnitude were used to identify pupil sub-apertures responsible for each radial perceived starburst line. Local intensity distributions within the starbursts mapped onto unique sub-regions of the pupil of both phakic and pseudophakic eyes, consistent with the hypothesis that ocular aberrations are the cause of starbursts. In paraxially focused eyes, the size of starbursts is predicted by the amount of spherical aberration, and starburst orientation is either the same or 180 deg rotated from the pupil region that creates each starburst line. No starbursts are seen when the pupil diameter is smaller than 3 mm. Replacing the eye's natural lens with a radially symmetric and optically homogeneous intraocular lens reduced the observed number of starbursts by 50%. Geometrical optics modeling including the measured aberrations of an individual eye can reveal point spread function structure that captures some of the key elements of the entopic perceptions.
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Investigative Ophthalmology & Visual Science, May 1, 2003
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Advances in Experimental Medicine and Biology, 2002
ABSTRACT
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Optometry and Vision Science, Dec 1, 2000
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Contact Lens and Anterior Eye, Dec 1, 2012
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Investigative Ophthalmology & Visual Science, Apr 17, 2010
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Ophthalmic and Visual Optics
Contact and intraocular lens designers and manufacturers have considered many strategies to provi... more Contact and intraocular lens designers and manufacturers have considered many strategies to provide presbyopes with good near and distant vision. In particular, considerable effort has been made recently to design simultaneous vision bifocal contact and intraocular lenses (CL and IOL). These simultaneous vision bifocals create dual images simultaneously on the retina (we will refer to this as monocular diplopia). Very little is known about the visual impact of such an optical situation.
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Investigative Ophthalmology & Visual Science, May 1, 2003
ABSTRACT
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Investigative Ophthalmology & Visual Science, 2005
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Investigative Ophthalmology & Visual Science, 2008
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Investigative Ophthalmology & Visual Science, 2004
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Investigative Ophthalmology & Visual Science, 2010
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Investigative Ophthalmology & Visual Science, 2011
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Investigative Ophthalmology & Visual Science, 2004
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Ophthalmic and Visual Optics
The optical apparatus of the eye presents a low-pass spatial filter to the front end of the visua... more The optical apparatus of the eye presents a low-pass spatial filter to the front end of the visual system which is a potential limiting factor for any visual task. In the well-focused eye, chromatic aberration and diffraction are thought to be the major optical factors limiting vision.1-3 Recent evidence indicates that ocular chromatic aberration can significantly reduce image contrast, resulting in loss of contrast sensitivity and visual acuity, and may also inject large artifacts into the retinal image of colored visual targets.4,5 Such problems are likely to be exacerbated by the use of achromatizing lenses6 or other optical apparatus such as clinical test instrumentation7 which may shift the eye's achromatic axis away from the fovea, thus exposing central vision to transverse aberration from which it is normally protected.8 Consequently, it is important to have available an accurate, mathematically tractable model of ocular chromatic aberration to help gauge the potential ma...
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Journal of the Optical Society of America, Mar 12, 2019
Starbursts seen around small bright lights at night have been attributed to optical scatter, diff... more Starbursts seen around small bright lights at night have been attributed to optical scatter, diffraction, or aberrations. We manipulated pupil aperture and aberrations to investigate the entopic appearance of perceived starbursts. The impact of circular, annular, and wedge-shaped pupil apertures, and spherical aberration sign and magnitude were used to identify pupil sub-apertures responsible for each radial perceived starburst line. Local intensity distributions within the starbursts mapped onto unique sub-regions of the pupil of both phakic and pseudophakic eyes, consistent with the hypothesis that ocular aberrations are the cause of starbursts. In paraxially focused eyes, the size of starbursts is predicted by the amount of spherical aberration, and starburst orientation is either the same or 180 deg rotated from the pupil region that creates each starburst line. No starbursts are seen when the pupil diameter is smaller than 3 mm. Replacing the eye's natural lens with a radially symmetric and optically homogeneous intraocular lens reduced the observed number of starbursts by 50%. Geometrical optics modeling including the measured aberrations of an individual eye can reveal point spread function structure that captures some of the key elements of the entopic perceptions.
Bookmarks Related papers MentionsView impact
Investigative Ophthalmology & Visual Science, May 1, 2003
Bookmarks Related papers MentionsView impact
Advances in Experimental Medicine and Biology, 2002
ABSTRACT
Bookmarks Related papers MentionsView impact
Optometry and Vision Science, Dec 1, 2000
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Contact Lens and Anterior Eye, Dec 1, 2012
Bookmarks Related papers MentionsView impact
Investigative Ophthalmology & Visual Science, Apr 17, 2010
Bookmarks Related papers MentionsView impact
Ophthalmic and Visual Optics
Contact and intraocular lens designers and manufacturers have considered many strategies to provi... more Contact and intraocular lens designers and manufacturers have considered many strategies to provide presbyopes with good near and distant vision. In particular, considerable effort has been made recently to design simultaneous vision bifocal contact and intraocular lenses (CL and IOL). These simultaneous vision bifocals create dual images simultaneously on the retina (we will refer to this as monocular diplopia). Very little is known about the visual impact of such an optical situation.
Bookmarks Related papers MentionsView impact
Investigative Ophthalmology & Visual Science, May 1, 2003
ABSTRACT
Bookmarks Related papers MentionsView impact
Investigative Ophthalmology & Visual Science, 2005
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Investigative Ophthalmology & Visual Science, 2008
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Investigative Ophthalmology & Visual Science, 2004
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Investigative Ophthalmology & Visual Science, 2010
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Investigative Ophthalmology & Visual Science, 2011
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Investigative Ophthalmology & Visual Science, 2004
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