Archive for the ‘Optics’ Category

It can sometimes be useful to estimate the Snellen or logMAR acuity of a patient based on the size of the font they read at near. While there are tables available showing the conversions, this can not cover all font sizes and reading distances. With some basic trigonometry, you can do the calculations yourself. First, […]

Power crosses are useful diagrams for doing lens power calculations in optics. Drawing the power crosses in LaTeX can be tedious, especially if you need to draw multiple power crosses in the same document. The code below creates a new command, \powercross{front@90}{front@180}{back@90}{back@180}, which will draw the power crosses for you and calculate the final lens […]