Difference between revisions of Guide:Reading glasses prescriptions
| (One intermediate revision by one other user not shown) | |||
| Line 4: | Line 4: | ||
==Spherical== | ==Spherical== | ||
{{main|Spherical}} | {{main|Spherical}} | ||
Spherical is the overall correction, in all directions. It is measured in [[diopters]]. A minus value means the lense is used correct [[myopia]] and a plus value means it is used to correct [[presbyopia]] and/ or [[hyperopia]]. | Spherical is the overall correction, in all directions. It is measured in [[diopters]]. A minus value means the lense is used correct [[myopia]] and a plus value means it is used to correct [[presbyopia]] and/or [[hyperopia]]. | ||
==Cylinder== | ==Cylinder== | ||
| Line 23: | Line 23: | ||
| Decreases myopia correction || Increases presbyopia correction | | Decreases myopia correction || Increases presbyopia correction | ||
|} | |} | ||
[https://www.youtube.com/watch?v=0AyE1BmKUh8 Explanation of positive vs. negative cyl correction] | |||
==Axis== | ==Axis== | ||