color vision

The method of color vision inspection generally includes a color blind inspection mirror, a color blind inspection light, a false color matching table (color blind inspection table), and a colored cashmere bundle. In the recruitment and enrollment physical examination, the false color table and the colored velvet bundle are commonly used for color vision inspection. The visible light of the human eye has a wavelength of 390 to 780 nm, and generally 120 to 180 different colors including seven main colors of purple, blue, cyan, green, yellow, orange, and red are discernible. Basic Information Specialist Category: Ophthalmic Examination Category: Physical Examination Applicable gender: whether men and women apply fasting: not fasting Tips: Please relax when checking. Normal value The color of the object can be correctly identified. Clinical significance Abnormal result The mechanism of color perception is currently explained by the "three primary colors theory". According to this theory, there are three cones or corresponding photoreceptors on the retina that are particularly sensitive to the wavelengths of red, green and blue light. When different wavelengths of light enter the eye, they can cause sensitive wavelengths to match. Or similar cones have different degrees of excitement, so the corresponding color vision is produced in the brain. If the three cones are stimulated to the same extent, they will produce a white color vision. If the lack of color vision or color vision is abnormal, it is color blindness or color weakness. Precautions Ensure that the inspectors understand the usage and significance of each picture of the color blind inspection chart to ensure that the physical examination work is carried out quickly and accurately. Under bright diffuse light or fluorescent light, the eye to be inspected is 60~80cm away from the surface. Inspection process Color vision method. Not suitable for the crowd There are no absolute taboos. Adverse reactions and risks Generally no adverse reactions.