All Opticians must know how to measure for bifocals for a patient’s eyewear, or eyeglasses. Sure, today there is equipment that will do this for us, however, in order to be efficient, one must know how to do it quickly and easily.
- Seat the patient directly in front of you
- Place the adjusted frame onto the patient’s face and ask patient to adjust to how they will more than likely wear them if necessary.
- Instruct patient to look into the distance, at least twenty feet away.
- You, the Optician, adjust your seat so that you are seated at the same height as the patient.
- Use a permanent marker (Sharpie), place a line on the lens directly under the lower eyelid of patient. Do this to both eyes.
- Remove the eyewear.
- Measure the segment height with a PD stick.
- Document this for the laboratory.

This is the same method used for measuring no-line bifocals into a eyeglasses frame as well.