Pupil distance refers to the horizontal distance between the pupils' centers of two eyes. It is necessary to accurately measure and calculate the displacement based on the pupil distance and cheapest eyeglasses online frame size during processing to achieve the actual pupil distance.

Many people have different distances between the pupils of one eye. More suitable glasses can be made only by accurately measuring the distance between the pupils of one eye and making them separately.

Especially for high myopia, the production of pupillary distance is very strict. Otherwise, a prism effect will occur. Myopia lenses can be understood as a combination of many prisms with the bottom facing outwards and the top facing towards the center.

Looking at the center point, things won't deviate. The best place to buy eyeglasses has higher precision in processing and produces more comfortable glasses.

Pupil height refers to the vertical distance from the point through which the eyes pass when looking straight into the distance after wearing the frame on the face to the lowest edge of the lens. Pupil height is a point repeatedly mentioned.

Nowadays, with the popularity of large frames and online shopping, if you don't consider high-pupil glasses, it is likely, not suitable. The eyes cannot see through the optical center point, which also produces the prism effect.

Only by observing the position of the glasses and considering the height of the pupils after wearing them on the face can we try to avoid discomfort or even failure in fitting the glasses due to the height of the pupils. A frame height that is too large can lead to the need for very high pupil height, which may not be good for looking far or near and may not be good for looking near or far.