The human eye is unique in that it accommodates for different light intensities and also focuses light rays that come from different distances from the eye. Light is then converted into impulses and sent to the brain where this image is perceived as what it looks like. Vision is very dependent on light. The light rays are reflected off object and then make their way into the eye. The light rays enter the eye through the cornea and the cornea refracts the light as it enters the eye. After passing through the cornea the light rays pass through the opening called the pupil. The iris is the part of the eye that controls the dilation of the pupil. This allows a certain amount of light into the eye.
How we see colors- The retina has cells called rods and cones. The rods and cones absorb light rays and change them into electrical signals. The electrical signals are then transmitted to the brain, which produces the familiar sensations of color. If any part of this system is damaged, then people may lose their ability to see some or all colors.
Color Blindness- The inability to perceive differences between some or all colors Two main types of colorblindness: Red/Green Blue/Yellow
Causes- Often due to genetics Also can result from damage to certain areas of the body… Eye, Nerves, Brain, Exposure to certain chemicals
Signs/Symptoms- Difficulty distinguishing between reds and greens Difficulty distinguishing blues and greens Objects appearing as various shades of gray Reduced vision Nystagmus-involuntary eye movement
Diagnosis- Most commonly detected with Ishihara Test Plates Ishihara Test Plates-Special colored charts that are composed of colored dots that form the shape of a number If the patient can not distinguish between certain colors then they will not be able to detect the number on the chart.
Treatment- No known treatment People with colorblindness learn to associate certain colors with objects to better identify colors. This helps in determining and recognizing certain colors.
Statistics- The most common form of color blindness is Red/Green Color Blindness Consists of 99% of Color Blindness cases Blue/Yellow color blindness is rare Total color blindness is extremely rare
How we see colors- The retina has cells called rods and cones. The rods and cones absorb light rays and change them into electrical signals. The electrical signals are then transmitted to the brain, which produces the familiar sensations of color. If any part of this system is damaged, then people may lose their ability to see some or all colors.
Color Blindness- The inability to perceive differences between some or all colors Two main types of colorblindness: Red/Green Blue/Yellow
Causes- Often due to genetics Also can result from damage to certain areas of the body… Eye, Nerves, Brain, Exposure to certain chemicals
Signs/Symptoms- Difficulty distinguishing between reds and greens Difficulty distinguishing blues and greens Objects appearing as various shades of gray Reduced vision Nystagmus-involuntary eye movement
Diagnosis- Most commonly detected with Ishihara Test Plates Ishihara Test Plates-Special colored charts that are composed of colored dots that form the shape of a number If the patient can not distinguish between certain colors then they will not be able to detect the number on the chart.
Treatment- No known treatment People with colorblindness learn to associate certain colors with objects to better identify colors. This helps in determining and recognizing certain colors.
Statistics- The most common form of color blindness is Red/Green Color Blindness Consists of 99% of Color Blindness cases Blue/Yellow color blindness is rare Total color blindness is extremely rare
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