Cataracts are a common eye disease in ophthalmology and are currently the leading cause of blindness in China, posing a serious threat to the eye health of the public. In the early stages of cataract formation, the lens inside the eyeball usually has only mild cloudiness. Visually, from the outside, the cloudiness in the pupil area cannot be seen with the naked eye. However, when a doctor uses a slit lamp microscope for enhanced observation, cloudy patches inside the lens can be detected. At this time, the patient's vision decline is not significant, and surgery might not be immediately necessary; it is feasible to continue monitoring the changes in vision. As the cataract progresses, the area of cloudiness in the lens gradually expands. When it develops to the middle or late stage, white patches can be seen in the pupil area with the naked eye, and surgical treatment becomes necessary.