Eyes (also called eyes, eyes) are organs that can perceive light. The simplest eye structure can detect the brightness of the surrounding environment, and the more complex eye structure can provide vision.
Compound eyes usually exist in arthropods (such as insects), and usually consist of many simple small eye surfaces, and produce one image (instead of multiple images as usually imagined).
In many vertebrates and some mollusks, the eyes image by projecting light to the photosensitive retina, where the light is received and converted into signals and transmitted to the brain through the optic nerve.
Introduction:
The eyes are the most important organs in human senses, and about 80% of the knowledge in the brain is obtained through the eyes. Reading, looking at pictures, enjoying pictures, looking at people and enjoying beautiful scenery all require eyes. The eyes can distinguish different colors and brightness of light, and convert this information into nerve signals and transmit them to the brain.
The human eye is the benchmark of telescope magnification, that is to say, the magnification is 1, and the aperture is the size of the pupil of the human eye, which varies with the change of illumination intensity and generally fluctuates between 2-7 mm.
Imaging principle:
The eye can change the focal length of the lens by adjusting the curvature (refraction) of the lens, so as to obtain an inverted and reduced real image. The farthest point that the eyes can see is called the adjustment far point, and the far point that the eyes can see is extremely far; The closest point that the eye can see is called the accommodation near point, and the accommodation range is called between two points. The near point of normal eyes is about 10 cm away from the eyes.
Apparent distance:
The apparent distance of myopia is generally around 10 cm, (the apparent distance refers to the distance that the human eye is not tired when reading for a long time), and the apparent distance of the right eye is around 25 cm, so the human eye is not tired when reading at this distance.
Visible light frequency:
According to scientific research, the expression of eyes is most closely related to the sun. In fact, the development of human eyes into such a complex, dexterous and vivid optical system is the result of long evolution of human beings in the process of natural selection.
The above contents refer to Baidu Encyclopedia Eye.