Method and apparatus that facilitates determining refractive error

A non-transitory computer-readable storage medium, comprising:

• a memory component configured to store computer-readable instructions, the computer-readable instructions including instructions for performing the following acts:
• displaying a line pattern to a user, the line pattern including a first line and a second line;
• varying an aspect of the line pattern, the aspect being at least one of a width between the first line and the second line, a thickness of the first line or the second line, a darkness of the first line or the second line, or a color of the first line or the second line;
• receiving an input corresponding to a focused line pattern variance selected by the user, the input identifying a particular line pattern aspect combination associated with the focused line pattern variance;
• and
• quantifying a refractive error of the user based on the input and an approximate distance between the line pattern and the user, the quantifying further comprising accessing a lookup table, wherein the lookup table associates a particular refractive error value to each of a plurality of line pattern aspect combinations.