Question

Usually a PD measuring instrument will allow both dis- tance and near PD to be measured. This is done through the use of a movable internal lens that changes the image distance and convergence for the subject. The near read- ings are carried out in the same manner as the distance readings.

True or false?

Answer 1

False. Near PD measurements are not carried out in the same manner as distance measurements in a PD measuring instrument.

Step-by-step explanation:

False. A PD (pupillary distance) measuring instrument typically allows both distance and near PD to be measured through the use of a movable internal lens that changes the image distance and convergence for the subject. However, the process of measuring near PD is not carried out in the same manner as distance readings. Near PD is measured by bringing the eyes closer to the instrument, simulating the convergence that occurs when focusing on near objects.