often compare the functioning of the eye with a camera. The pupil would act as a diaphragm, the film retina, cornea, lens and lens is equivalent to zoom the camera view to get a good approach. The analogy does not end here, as well as in the camera the image formed on the retina is inverted. But this is no problem because the brain is responsible for giving the back to see it properly.
sensitivity and vision rates
As in the picture, the amount of light plays an important role in vision. Thus, in good lighting conditions (more than 3 cd/m2) as happens during the day, the vision is clear, detailed and very well distinguish colors is photopic vision. Lower levels to 0.25 cd/m2 color disappears and the sense of vision is more sensitive to blue and light intensity. It is called scotopic vision. In intermediate situations, the ability to distinguish colors decreases as the amount of light down from a high sensitivity to yellow to blue. It is the vision mesiópica.
Under these conditions, we define sensitivity curves of the eye to visible light for a given observer pattern having a maximum wavelength of 555 nm (yellow green) for photopic vision and a 480 nm (blue-green) for scotopic vision. Maximum displacement of the curve by decreasing the amount of light received is called the Purkinje effect.
sensitivity curves ojo.Toda light source that emits near-maximum values \u200b\u200bfor daylight vision (555 nm) will produce optimum energy efficiency for maximum light sensation in the eye with minimal power consumption. However, if the source does not provide good color rendition can lead to counterproductive results.
The accommodation is called accommodation to the eye's ability to automatically focus on objects at different distances. This function is carried out in crystalline form to the effect varies. But this capacity is lost over the years due to loss of elasticity that suffers, is what is known as presbyopia or eyestrain and increases the focal length and the minimum necessary amount of light to form a sharp image.
Adaptation Adaptation is the ability of the eye to adjust automatically to changes in light levels. Is due to the ability of the iris to regulate the opening of the pupil and photochemical changes in the retina. To go from dark to light environments the process is very fast but otherwise it is much slower. After a minute is acceptable adaptation. As time passes, we see better in darkness and half hour and we see quite well. Complete adaptation occurs after an hour.
visual field
Returning to the example of the camera, the human eye also has a visual field. Each eye sees about 150 degrees above the horizontal plane and the overlay of both are comprised of 180 º. In the vertical plane only about 130 degrees, 60 degrees above the horizontal and 70 degrees below.
visual field of each eye is monocular type, without a sense of depth, with the vision in the area of \u200b\u200boverlap of the two fields of type binocular. The sense of depth or three-dimensional view of the brain occurs when two images overlaid and interpreted.
sensitivity and vision rates As in the picture, the amount of light plays an important role in vision. Thus, in good lighting conditions (more than 3 cd/m2) as happens during the day, the vision is clear, detailed and very well distinguish colors is photopic vision. Lower levels to 0.25 cd/m2 color disappears and the sense of vision is more sensitive to blue and light intensity. It is called scotopic vision. In intermediate situations, the ability to distinguish colors decreases as the amount of light down from a high sensitivity to yellow to blue. It is the vision mesiópica.
Under these conditions, we define sensitivity curves of the eye to visible light for a given observer pattern having a maximum wavelength of 555 nm (yellow green) for photopic vision and a 480 nm (blue-green) for scotopic vision. Maximum displacement of the curve by decreasing the amount of light received is called the Purkinje effect.
sensitivity curves ojo.Toda light source that emits near-maximum values \u200b\u200bfor daylight vision (555 nm) will produce optimum energy efficiency for maximum light sensation in the eye with minimal power consumption. However, if the source does not provide good color rendition can lead to counterproductive results. The accommodation is called accommodation to the eye's ability to automatically focus on objects at different distances. This function is carried out in crystalline form to the effect varies. But this capacity is lost over the years due to loss of elasticity that suffers, is what is known as presbyopia or eyestrain and increases the focal length and the minimum necessary amount of light to form a sharp image.
Adaptation Adaptation is the ability of the eye to adjust automatically to changes in light levels. Is due to the ability of the iris to regulate the opening of the pupil and photochemical changes in the retina. To go from dark to light environments the process is very fast but otherwise it is much slower. After a minute is acceptable adaptation. As time passes, we see better in darkness and half hour and we see quite well. Complete adaptation occurs after an hour.
visual field Returning to the example of the camera, the human eye also has a visual field. Each eye sees about 150 degrees above the horizontal plane and the overlay of both are comprised of 180 º. In the vertical plane only about 130 degrees, 60 degrees above the horizontal and 70 degrees below.
visual field of each eye is monocular type, without a sense of depth, with the vision in the area of \u200b\u200boverlap of the two fields of type binocular. The sense of depth or three-dimensional view of the brain occurs when two images overlaid and interpreted.
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