Systems and methods for altering visual acuity

Abstract

Provided are methods, systems, and apparatus for altering a modulation transfer function of an imaging system. The described methods, systems and apparatus can be used to temporarily alter visual acuity of a subject.

What is claimed is: 
     
         1 . A system operable to effect a temporary change in a modulation transfer function (MTF) of a target imaging system, comprising:
 a light source operable to produce light for transient propagation onto at least a portion of the target imaging system;   a power source in operative communication with the light source and configured to effect the production of light from the light source; and   a transmission unit in operative communication with the light source and configured to propagate the produced light onto at least a portion of the target imaging system, wherein the propagated light is configured for absorbance by the portion of the target imaging system; the absorbance causing an increase in temperature and a change in a refractive index profile of at least the portion of the imaging system, the change in refractive index profile producing a temporary change in the MTF of the imaging system.   
     
     
         2 . The system of  claim 1 , wherein the propagated light has a wavelength in the range of 1100 nanometers (nm) to 2500 (nm). 
     
     
         3 . The system of  claim 1 , wherein the imaging system is an eye. 
     
     
         4 . The system of  claim 3 , wherein the portion of eye that absorbs the light is anterior to the retina. 
     
     
         5 . The system of  claim 4 , wherein the portion of the eye that absorbs the light is selected from the group consisting of the vitreous humor, the lens, the aqueous humor, and the cornea. 
     
     
         6 . The system of  claim 5 , wherein the absorption of light causes a non-uniform index of refraction change in the cornea, aqueous humor, lens or vitreous humor. 
     
     
         7 . The system of  claim 3 , wherein the portion of the eye that absorbs the light is the retina or tissue posterior to the retina. 
     
     
         8 . The system of  claim 3 , wherein the absorption of light disrupts visual acuity. 
     
     
         9 . The system of  claim 3 , wherein the eye is a human eye. 
     
     
         10 . The system of  claim 9 , wherein an irradiance of the propagated light at a location where the target imaging system receives the propagated light is between 0.001 W/cm 2  and 500 W/cm 2 . 
     
     
         11 . The system of  claim 9 , wherein an irradiance of the propagated light at a location where the target imaging system receives the propagated light is between 0.005 W/cm 2  and 50 W/cm 2 . 
     
     
         12 . The system of  claim 9 , wherein an irradiance of the propagated light at a location where the target imaging system receives the propagated light is between 0.1 W/cm 2  and 5 W/cm 2 . 
     
     
         13 . The system of  claim 1 , wherein the light source is a first laser light source. 
     
     
         14 . The system of  claim 1 , further comprising a second light source operable to produce light for transient propagation onto at least a portion of the target imaging system. 
     
     
         15 . The system of  claim 14 , wherein the transmission unit is in operative communication with the second light source and is configured to propagate light produced by the second light source onto at least a portion of the target imaging system. 
     
     
         16 . The system of  claim 15 , wherein the propagated light from the second light source has a wavelength in the range of 450 nm to 650 nm. 
     
     
         17 . The system of  claim 15 , wherein the transmission unit is operable to co-align light from the first and second light sources for propagation onto at least a portion of the target. 
     
     
         18 . The system of  claim 14 , wherein an irradiance of light from the second light source at a location where the target imaging system receives the propagated light is greater than 0.001 mW/cm 2 . 
     
     
         19 . A system to temporarily alter visual acuity of a subject, the system comprising:
 a first light source configured to produce infrared light in an infrared wavelength spectrum for transient propagation into an eye of the subject;   a second light source configured to produce visible light in a visible wavelength spectrum for transient propagation into the eye of the subject; and   a transmission unit configured to propagate the infrared light and the visible light into the eye,   wherein the light propagated into the eye temporarily alters visual acuity of the subject.   
     
     
         20 . The system of  claim 19 , wherein the first light source is configured to produce the infrared light having a first irradiance sufficient to cause temperature gradients in the eye, the temperature gradients causing changes in a refractive index profile in the eye. 
     
     
         21 . The system of  claim 19 , wherein second light source is configured to produce the visible light at a second irradiance sufficient to saturate light receptors in the eye. 
     
     
         22 . The system of  claim 19 , the transmission unit further comprising an optical system configured to co-align the infrared light and the visible light. 
     
     
         23 . The system of  claim 22 , wherein the optical system is configured to produce a co-aligned infrared light and visible light with a spot size of about 10 cm to 2.0 m at a target distance of about 500 meters (m). 
     
     
         24 . The system of  claim 19 , wherein the first light source produces infrared light in a wavelength range of 1100 nm to 2500 nm. 
     
     
         25 . The system of  claim 24 , wherein the first light source produces infrared light in a wavelength range of 1100 nm to 1700 nm. 
     
     
         26 . The system of  claim 25 , wherein the first light source produces infrared light having a wavelength of about 1318 nm. 
     
     
         27 . The system of  claim 19 , wherein the second light source produces visible light in a wavelength range of 450 nm to 650 nm. 
     
     
         28 . The system of  claim 27 , wherein the second light source produces visible light having a wavelength of about 535 nm. 
     
     
         29 . The system of  claim 19 , wherein the transmission unit is configured to propagate the infrared light and visible light for a distance greater than 2 km before entering the eye. 
     
     
         30 . The system of  claim 19 , wherein the transmission unit is configured to propagate the infrared light and visible light for a distance of about 100 m before entering the eye. 
     
     
         31 . The system of  claim 14 , wherein the transmission unit is configured to propagate the infrared light and visible light for a distance of about 10 m before entering the eye. 
     
     
         32 . The system of  claim 19 , further comprising at least one additional light source configured to produce infrared light in an infrared wavelength spectrum for transient propagation into the eye,
 wherein the infrared wavelength of the infrared light produced by the first light source is different from the infrared wavelength of the infrared light produced by the at least one additional light source.   
     
     
         33 . The system of  claim 19 , further comprising at least one additional light source configured to produce visible light in visible wavelength spectrum for transient propagation into the eye,
 wherein the visible wavelength of the visible light produced by the at least one additional light source is different from the visible wavelength of the visible light produced by the second light source.   
     
     
         34 . A method for altering visual acuity of a subject comprising:
 propagating visible light in a visible wavelength spectrum into the eye, the visible light generating glare at a glare angle, wherein an area of the retina on which the visible light is incident is related to the glare angle; and   modifying the propagated visible light to increase the glare angle, an area of the retina on which the modified visible light is incident being greater than the area of the retina on which the propagated visible light is incident, wherein the modified visible light alters visual acuity of the subject.   
     
     
         35 . The method of  claim 34 , wherein a power required to propagate the modified visible light is less than a power required to propagate the visible light that is not modified. 
     
     
         36 . The method of  claim 34 , wherein the visible light is a laser having a retinal spot size, wherein modifying the visible light to increase the glare angle increases the retinal spot size of the visible laser. 
     
     
         37 . The method of  claim 34 , wherein modifying the visible light comprises:
 propagating an infrared light in an infrared wavelength spectrum;   co-aligning the infrared light with the visible light to form co-aligned light; and   propagating the co-aligned light into the eye.   
     
     
         38 . The method of  claim 37 , wherein the visible light has an irradiance sufficient to saturate the receptors in the portion of the eye on which the visible light is incident, and
 wherein the infrared light has an irradiance sufficient to cause a temperature gradient at the portion of the eye, the temperature gradient causing a change in a refractive index profile of the portion of the eye.   
     
     
         39 . The method of  claim 37 , wherein the visible light is incident on the retina, and
 wherein the infrared light causes the temperature gradient at a region anterior to the retina.   
     
     
         40 . A method for temporarily altering the visual acuity of a subject, comprising:
 projecting infrared wavelength light into an eye of the subject;   projecting visible wavelength light into the eye of the subject, wherein the projected infrared and projected visible wavelength light are co-aligned, and wherein the infrared wavelength light and visible wavelength light temporarily alter visual acuity of the subject.   
     
     
         41 . The method of  claim 40 , wherein the infrared wavelength light is projected in co-alignment with the projected visible wavelength light.