Difference between revisions of User:User
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In 2013, my parents switched optometrists because the location was more convenient. The optometrist measured a -0.5 D change (-2/-1.75) and was reluctant to adjust by +0.25 D (-1.75/-1.5) but still did it, and recommended me to use glasses all of the time. My uncorrected acuity was probably 20/200, with a barely readable E at the top of the chart. | In 2013, my parents switched optometrists because the location was more convenient. The optometrist measured a -0.5 D change (-2/-1.75) and was reluctant to adjust by +0.25 D (-1.75/-1.5) but still did it, and recommended me to use glasses all of the time. My uncorrected acuity was probably 20/200, with a barely readable E at the top of the chart. | ||
In 2015, my parents went back to the same location, with a different optometrist, and she increased the diopter gap between eyes and added cylinder (-2.75x 0.25x180/-2.00 -0.50x60). When I wore the glasses, which are polycarbonate instead of Trivex, I saw lots of distortion and [[chromatic aberration]]. Fortuitously, while I was researching chromatic aberration in lens materials and whether it has something to do with polycarbonate or the cylinder, I found an endmyopia article about that topic and decided to give it a shot by using my old glasses as normalized. For this reason, I wrote about technical details of diopters and combining cylinders with different axes, in case it'll help someone find this place. I now know that CR39 plastic and Trivex are acceptable, but polycarbonate is garbage. | In 2015, my parents went back to the same location, with a different optometrist, and she increased the diopter gap between eyes and added cylinder (-2.75x 0.25x180/-2.00 -0.50x60). When I wore the glasses, which are polycarbonate instead of Trivex, I saw lots of distortion and [[chromatic aberration]]. <s>Fortuitously</s> (unfortunately, the cylinder had effect and caused many issues for me later), while I was researching chromatic aberration in lens materials and whether it has something to do with polycarbonate or the cylinder, I found an endmyopia article about that topic and decided to give it a shot by using my old glasses as normalized. For this reason, I wrote about technical details of diopters and combining cylinders with different axes, in case it'll help someone find this place. I now know that CR39 plastic and Trivex are acceptable, but polycarbonate is garbage. | ||
My parents switched optometrists yet again. In 2018, the autorefractor measured -1.5 spherical equivalent with some cylinder. The optometrist measured -1.5 spherical for both eyes and recommended using it for distance only, confirming that either the previous prescription was ridiculous (which is true) or that reduction is possible (which is also true). | My parents switched optometrists yet again. In 2018, the autorefractor measured -1.5 spherical equivalent with some cylinder. The optometrist measured -1.5 spherical for both eyes and recommended using it for distance only, confirming that either the previous prescription was ridiculous (which is true) or that reduction is possible (which is also true). | ||