Vision information

Eyesight problems and Vision correction - About-vision.com
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Vision information
UV radiation

Ultraviolet rays are the component of sunlight and is divided into UV-A and UV-B and UV-C radiation. UVA rays tan skin and is due to premature skin aging. UV-B rays cause sunburn and are often associated with skin cancer and eye problems such as cataracts. UV-C rays are most dangerous. There are, fortunately, blocked by ozone layer and do not get to the earth's surface.

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Vision and driving

vision_and_drivingWhen driving a motor vehicle a driver has to continuously monitor not only what is happening on the road but also the data on the panel board. The tilting of his head (in average around 30 degrees) leads to reduction of the sharpness of the image of events happening on the road which is caused by the movement of the eyes. When looking at the speedometer the movement of the eyes exceeds the target by 5 degrees in average and it is immediately balanced with the subsequent movement of the eyes. The creation of sharp image on the retina leads to its processing and to the realization of what is seen. However, we suppose that the size of the figures, which are being read, has to be at minimum 5 times bigger than the minimal size which enables them to be differentiated. Therefore the look can return to the original position only after the processing and implementation of the information.

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Human eye and color vision

color vision and the human eyeThe color vision is a very complicated psychophysical process during which human eye distinguishes different colors. From the physical point of view the color does not exist and it is only a visual perception which is conditioned by the wavelength of the light. The certain part of the spectrum reflects from different objects, then it falls on the eye where it causes the irritation of the light sensitive elements which react to colur – the cones. For its realization, it is necessary to have a correct and undisturbed function of the eyesight and the human eye as the receiving organ, the optical path as the transmitting system and the centers of the brain thanks to which we distinguish and thus they are the analyzer of the perception.

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Human eyesight

human_eyesightHuman eyesight is a sense which enables animals to perceive the light, different colors, shapes and it serves to the general perception of the environment. It is oriented mainly towards the perception of contrast and thus even contours and it significantly helps with orientation in space. For a human being the eyesight is the most important sense and that is mainly because almost 80% of information from our surroundings is perceived through it.

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