What portion of the progressive lens should be used to verify the distance prescription when the lenses arrive from the lab?

In the evaluation of progressive lenses, the center of the distance arc is the correct area to assess when verifying the distance prescription. The distance prescription is typically situated at the upper part of the lens, and the center of the distance arc corresponds to the location where the optical center for distance vision is found. This ensures that the measurements align with the intended visual correction for distance.

When lenses arrive from the lab, clinicians focus on this area to confirm that the distance prescription has been accurately produced according to the specified parameters. This verification process is crucial for ensuring visual comfort and clarity for the patient.

Other points such as the major reference point and the prism reference point serve different purposes. The major reference point is often used for measuring the fitting parameters of the lens, while the prism reference point relates to the location where any prescribed prism effects should be achieved. The center of the fitting cross is used to align the overall fitting of the lens but does not specifically pertain to the distance prescription. Thus, focusing on the center of the distance arc is essential for precision in distance vision correction.