Color vision is an important part of human vision. The feeling and reaction to color is a complex system full of infinite mysteries. If something goes wrong in the process of color discrimination, the ability of human eyes to distinguish colors will be hindered. This situation is called color vision disorder, that is, color blindness or color weakness.
1875, a serious train collision occurred in Laagland, Sweden-because the driver was color blind and misread the signal. Since then, color discrimination has become an essential item for physical examination.
Generally speaking, color blindness means that you can't distinguish some or all colors, and color weakness means that your ability to distinguish colors is reduced. Color blindness is more common in red and green color blindness. The red blind can't tell the red light, and the green blind can't feel the green, which will undoubtedly have an impact on life and work. Weak color is mainly due to low color discrimination function, lighter than color blindness, and weak bonus color and green color. People with weak colors can see the colors seen by normal people, but their ability to recognize colors is slow or poor. When the light is dim, some of them are almost color blind or show color fatigue. Congenital factors are common in color blindness and color weakness.
Congenital color blindness or color weakness is a hereditary disease, which is related to gender. Clinical investigation shows that male color blindness accounts for 4.9%, while female color blindness accounts for only 0. 18%, and the number of male patients greatly exceeds that of female patients. This is because the genetic gene of color blindness exists on the X chromosome of sex chromosome and adopts the recessive inheritance mode of sex linkage. Usually, men are color blind, and women are color blind gene carriers with normal appearance, so there are more color blind men than women.
Congenital color vision disorder remains unchanged for life, and there is no specific treatment at present. Red or green soft contact lenses can be worn to correct it. Some people try acupuncture or traditional Chinese medicine, which is said to have certain effect, but it is still in the clinical research stage. Because color blindness and color weakness are hereditary diseases and can be passed on to future generations, it is an effective preventive measure to avoid consanguineous marriage and investigate the genetic disease history of the other family before marriage and take measures to reduce the birth rate of color blindness offspring.
A few color vision abnormalities are also found in acquired people, such as some fundus diseases and glaucoma. The degree of color vision disturbance caused by these eye diseases is relatively light and disappears with the recovery of primary eye diseases, so most of them have not attracted the attention of patients.
2. Weak color and driving:
Drivers should not be blind and weak. Because people who are red, green and blind can't correctly identify the colors of traffic command signals, traffic signs and signal lights (braking and steering) of the vehicles in front; People with weak colors can't tell whether the lights flashing with various colors are red or green at dusk and night, which may easily lead to traffic accidents.
3, weak color test:
How to determine color blindness and color weakness
2004-9- 10 14:43:00
The examination of color blindness and color weakness mostly adopts subjective examination, usually under bright natural light. Common inspection methods are as follows.
Pseudo-homochromy: It is usually called a color-blind book. It uses dots with the same tone depth but different colors to form numbers or figures, which can be seen clearly at a distance of 0.5m in natural light. Color blindness should be corrected during inspection, and each picture should not exceed 5 seconds. People with color vision impairment have difficulty in recognizing, misreading or being unable to read, and can confirm what kind of color vision abnormality they belong to according to the regulations of color blindness table.
Color harness test: it is to mix wool harnesses with different colors and shades, and let candidates pick out the harness with the same color as the standard harness. This method is time-consuming and can only be roughly qualitative but not quantitative, so it is not suitable for large-scale screening and inspection.
Color mixing tester: it is a spectral instrument designed by nagel according to the principle of red+green = yellow. The quantity required for matching red and green light can be recorded quantitatively to judge the abnormality of red and green color perception. This method can be qualitative or quantitative.
If your friend is still weak after many inspections, it is necessary to consider whether he can drive from the perspective of safety. !