Final answer:
The Rule of Halves is a mathematical principle used in ophthalmology for quick estimation of the near inset in eyeglass prescriptions, simplifying the calculation of additional lens power for close vision.
Step-by-step explanation:
Gerstman3 has simplified the calculation of the near inset with a rule which he calls the Rule of Halves. This rule is a mathematical principle used for quick estimation and calculations in optics, particularly in the field of ophthalmology where it is applied for determining the measurements for eyeglass prescriptions. The Rule of Halves provides a simplified method for calculating the near add, which refers to the additional corrective power needed for near vision tasks in bifocal or multifocal lenses. By using this rule, eye care professionals can streamline the process of determining the necessary lens power required for a patient to have clear vision at close distances.