Computer optometry cannot be used as a basis for fitting glasses

The computer optometry developed in the 1970s belongs to the objective optometry method. The machine used for this optometry is an instrument that combines optics, electronics, and mechanics, and its principle is basically the same as the retinal retinoscopy method. In addition, infrared red light source and automatic fog vision device are used to achieve the purpose of relaxing eye adjustment. Its simple operation and fast speed are a major advancement in optometry technology. However, various types of computer optometry machines inevitably produce certain errors. Although infrared light sources and automatic fog vision devices are used to relax and adjust, the influence of adjustment cannot be completely eliminated, especially for teenagers who have strong adjustment ability. Simply using computer optometry is often inaccurate. If computer optometry is necessary, eye drops should also be used to dilate the pupils and anesthetize the ciliary muscle before optometry. The main errors in computer optometry results are high myopia degree and astigmatism axis deviation. Therefore, the results of computer optometry can only be used as clinical reference and cannot be directly used as prescription for glasses.
The expression of glasses prescription: S： Representing a spherical lens, (-) indicates myopia, (+) indicates hyperopia or presbyopia; C： Representing cylindrical lenses, used for astigmatism; DS： Used to mark the optical power of a spherical lens.