The Wratten filter is used with the biomicroscope to?

The use of the Wratten filter with a biomicroscope is specifically aimed at enhancing the visualization of fluorescein dye. This filter helps to improve contrast and can allow for a clearer view of the areas where fluorescein is present, such as during the evaluation of corneal defects, tear film quality, and contact lens fitting.

When fluorescein dye is applied to the eye, it fluoresces under blue light, and the Wratten filter can enhance this effect, allowing the practitioner to more easily identify and assess areas of interest, such as abrasions or the overall health of the cornea.

Other options focus on different aspects of eye examination and contact lens fitting, like measuring lens power or examining corneal clarity, but they do not relate specifically to the function of the Wratten filter. Therefore, the primary purpose of the Wratten filter is tied to enhancing the evaluation of fluorescein, making it the correct choice.