If the right eye is 2 mm lower than the left eye while measuring heights for a first-time bifocal wearer, what is the best course of action?

When addressing differences in seg height measurements for a first-time bifocal wearer, discussing the option of using separate heights is the most advisable approach. This is particularly important because each eye may require a unique segment height to ensure optimal visual comfort and effectiveness of the lenses.

Using separate heights allows for personalization; if one eye is lower than the other, adjusting only one side can significantly enhance the wearer's experience. This specificity can help in accommodating any discrepancies in visual needs due to the anatomical differences in eye position, facilitating a more precise alignment of the optical centers of the lenses with the wearer's line of sight.

In contrast, other methods, such as splitting the difference or using the higher measurement, may not provide the necessary visual alignment required for bifocal wearers. Adjusting the frame to make seg heights equal may also lead to discomfort or ineffective vision correction, as it could misalign the lenses with the visual axis. Therefore, discussing the use of separate heights is a more tailored and practical solution for achieving the best fit and function in the specific situation of bifocal lens fitting.