Complex sentence: From a sketch it should be apparent that the optical diameter distance will be a bit "larger" than the ruler distance; it is in fact h +\\ frac + O\\ left (h ^ 3\\ right).
Split into simpler sentences: From a sketch it should be apparent that the optical diameter distance will be a bit "larger" than the ruler distance. It turns out to scale like h +\\ frac + O\\ left (h ^ 3\\ right).