That limit is efficient for measuring and selling glasses.
As a life-long user, glasses with an error of 0.5 are unacceptable for me. That's the amount of change over years when it is time to get new ones.
Not all deviations are measurement errors. There are potential variable conditions of the eye (e.g., spasm of accommodation and sugar level). An online solution that can consider them properly is definitively worth a patent.
As a life-long user, glasses with an error of 0.5 are unacceptable for me. That's the amount of change over years when it is time to get new ones.
Not all deviations are measurement errors. There are potential variable conditions of the eye (e.g., spasm of accommodation and sugar level). An online solution that can consider them properly is definitively worth a patent.