The pupillary distance (P.D.) measured while focusing on a point 24 inches in front is referred to as what type of P.D.?

The pupillary distance (P.D.) measured while focusing on a point 24 inches in front is referred to as intermediate P.D. because it pertains to the distance where vision is often focused during intermediate tasks, such as reading from a computer screen or viewing objects at an arm's length distance. This distance typically ranges from about 20 to 40 inches, making it the relevant measurement for activities that fall into this category.

When considering measurements for eyewear, distance PD is generally taken for far vision (e.g., when looking at objects that are much further away), while near PD is measured for tasks such as reading very close objects. In this case, since 24 inches is neither categorized strictly as far nor as very close, it fits into the intermediate range.

Understanding the context of each type of P.D. is crucial, as different types are applied based on the primary visual tasks that a person typically engages in, ensuring optimal vision correction and comfort.