Bifocal and varifocal glasses are multifocal spectacles which have more than a single power on their lenses. These glasses are beneficial to patients who have presbyopia and either one of myopia or hyperopia. As these glasses are more complex to use than the single vision glasses, the fit of the bifocal and varifocal glasses is as important as the quality of the pair. Generally, the fitting of the frames are done at the time of delivery, so one must always check from the beginning whether the frame is comfortable or not. Just like any other pair of prescription glasses, one must make sure that the arm tips sit comfortably behind your arms without putting any pressure. Even the slightest pressure over time will develop physical grooves and lead to a constant uncomfortable feeling.

In case of bifocal glasses, a flawlessly crafted one will help you to see at objects located nearby, by just swinging your eyes down by 15 degrees, while maintaining an erect head position. In case there is any mistake in the fit, then you will have to tilt your head to look at objects at a distance. If the bifocal glasses are too low then while reading you will be forced to keep the book close to your chest for a clearer vision.

Pupillary Distance (PD) is of major importance while designing the varifocal glasses. The measurement is critical and should be as accurate as possible, as the optical centre of the lenses should be directly in front of the pupils. As the optical centre is responsible for the clearest eyesight, PD is of primary importance. Measuring PD is not an easy task, and it is always wise to ask for professional help from the opticians. In case you are purchasing the varifocal glasses from online stores, you will need to put in the PD measurement. Generally, these online stores have an elaborate system which helps you to measure the PD with maximum ease. They have dedicated customer service teams as well who can assist you in the process.

You can also measure the pupillary distance on your own. You can stand in front of your mirror and use a ruler to measure the distance. This measurement has to be taken twice, with you focusing at an object situated at a distance and then looking at some nearby object. This taking measurement by yourself should not be done unless absolutely required. An optician will help you to get this measurement with more ease and accuracy.