When you decide to purchase a VR prescription lenses online. The first thing you should do is to confirm your prescription. Although reading a prescription may appear to be a dark art, our tips below will assist you in navigating and comprehending your prescription information.
Here's an example of a prescription. Prescriptions differ, so yours might not look the same.
Terms Required for VR Prescription Lenses
OD is an abbreviation for “oculus dexter” which is Latin for “right eye.”
OS is an abbreviation for “oculus sinister” which is Latin for “left eye.”
3. SPH (Spherical)
The spherical (SPH) determines if you have hypermetropia (plus sign) or myopia (minus sign). The number indicates the strength of the lens you need. A smaller number signifies a milder condition. PL stands for plano and implies that the eye has no refractive error.
4. CYL (Cylinder)
The abbreviation CYL refers to cylinder and indicates the seriousness of astigmatism. The axis depicts the angle at which your lens' cylindrical power must be set to correct it. You may notice DS in the column, which stands for diopter sphere and indicates that you do not have astigmatism.
5. AXS (Axis)
Axis is a number from 1 to 180. If your doctor has included cylinder power, there will also be an axis value to indicate positioning. Axis is measured in degrees and refers to where the astigmatism is located on the cornea.
ADD is used in Multifocal Lens (Bifocal, Trifocal and Progressive lens) to indicate the additional magnifying power for the bottom part of the lens. These terms are much more usual pertain to the extra correction you might need to focus on certain ranges. The Near Add is typically used for close activities like reading. The Intermediate Add refers to the extra strength of lens you would need to bring a mid-range distance into focus like staring at the computer screen.
Since the VR headsets usually have projected focal distances of about 4-6ft (1.2-1.8m) depending on the different VR headset. Bifocal, Progressive and Reading prescriptions will be reduced to the single vision lenses and adjusted for 4-6ft (1.2-1.8m) focal range.
If you do not have numbers under ADD then you do not need to worry about ADD. If you have numbers under ADD please choose Extra ADD/Prism Power and send us your full prescription by email email@example.com
8. Prism (Prismatic power)
Prism only appears on a low number of prescriptions. Prism on a prescription could show a triangle to describe prism instead of the word "Prism". It’s used when your doctor feels that compensation for eye alignment is necessary. The prismatic power, also known as prism, is intended to correct binocular vision difficulties in which both eyes have a hard time working together. The strength of the correction is indicated in the prism column, and the base column specifies in which direction the prism acts. The back vertex distance (BVD) is the measurement between the front of your eye and the lens of your glasses in millimeters. This distance, which might affect a lens's effective strength, is normally reserved for prescriptions with higher strengths.
If you do not have numbers under Prism then you do not need to worry about Prism. If you have numbers under ADD please choose Extra ADD/Prism Power and send us your full prescription by email firstname.lastname@example.org
9. PD (Pupillary Distance)
The distance between your pupils centered is measured by the Pupillary Distance (PD). This measurement must be as accurate as possible because it determines where you are looking through the lens of your glasses or VR insert.
The Oculus Quest headset has an inbuilt system which willl adjust to your optimal PD position. So you don't need the PD number for prescription lens. And this is our guide for PD measurement and adjustment.