The 5 Best Pupilometers [Ranked]
A pupilometer or pd meter is designed to accurately measure pupillary distance.
Most commonly it is utilized for eyeglass-fitting to ensure that the eyeglass lenses are properly centered on the visual axis.
A confusion regarding pupilometers is that they refer to two different types of tools, one that will measure the distance between pupils, and the other that will test your pupils responsiveness. We'll be examine pupillary distance pupilometers (Source).
A distance pupilometer works by assessing the distance between your nose bridge, where a pair of common eyeglasses typically sit, and your pupils' centers.
If you do not use a distance pupilometer to gather this measurement it's likely that the eyeglasses you or your customer ends up with will be a poor fit and even cause you some physical discomfort.
Most people who end up with incorrect eyeglasses complain of headaches and eyestrain- and you don't want that!
Let's take a look at 5 of the best-selling distance pupilometers on the market today.
Comparing The Options
|The Sunwin Digital Pd Meter||$$||9.8 x 5.9 x 3.9 inches||1.6 Ibs|
|The Gizmo Supply Optical Digital PD Meter Pupilometer||$||N/A||0.5 Ibs|
|The Gizmo Supply Optical Digital Pupilometer PD Meter||$$||3.7 x 11.8 x 8.6 inches||2 Ibs|
|The Gizmo Supply Digital LCD Optical Pupilometer (CE Approved)||$$$||9.4 x 13.7 x 4.1 inches||2.1 Ibs|
|The Sunwin Digital Pd Meter & Optical Pupil Meter||$$||9.8 x 5.9 x 3.9 inches||1.8 Ibs|
The Sunwin Digital Pupilometer has a binocular pupillary distance of between 45 and 82 mm, a left or right distance between 22.5 and 41 mm, and absolute value of indicated error of less than .5 mm. Users were for the most part impressed by its accuracy, relatively low cost, and solid build. While the instruction manual appears to have been run through Google translate and the pupil alignment light could be brighter, most users were able to get up and running pretty quickly.
- Solid build
- Accurate measurement Reasonably price
- Digitally stores readings
- Poor instruction manual
- Pupil alignment light could be brighter
How to measure pupillary distance
An optometrist will sometimes use a ruler to gather the millimeter pupillary distance measurement and then verify that measurement with the actual pupilometer device itself.
If you are looking to conduct an assessment using a pupilometer, the first thing you need to do is place it on your customer's face, atop the nose bridge, and instruct them to hold onto it as if it were a pair of common binoculars (Source).
You will then adjust the distance wheel to infinity.
What comes next, is that you will look through your end of the pupilometer and gather the distance measurement from the center of the pupil.
You will likely have to repeat this measurement couple of times until you're sure that you've gotten an accurate reading.
Interestingly, there are some smartphone apps that are equipped to measure pupillary distances. These apps will require that your smartphone have a camera as well as magnetic strip on a credit card to help provide accurate results.
Over at optiboard.com some optometrists have had a rousing discussion concerning the best method of calibrating and gathering an accurate measurement from their tools.
One confused optometrist rights that he has no idea what the numbers on the rotating knob are used for. One forum member responded that the numbers correspond to the distance patient eyes are aimed at. So, for example when it is set to 40 cm that is the distance that the patient's eyes are aimed at.
Home pupilometer use
The pupillary distance is the distance (in millimeters) between your pupils' centers. You'll need this specific measurement when purchasing eyeglasses. When you visit the eye doctor, they provide you with your prescription however the optometrist typically does not provide your pupillary distance. This happens because the optician that sells glasses measures your pupillary distance when you purchase glasses.
When your skeletal system is full-grown, at approximately age 20, your pupillary distance doesn't alter with age. Kid's pupillary distance, or PD, alters as they develop. If you wish to purchase eyeglasses on the internet and help save a lot of cash, and if you're uncertain regarding your PD measurement, buying one to make use of even once could save you money.
For those who have an expanding family, this gadget could save you a lot of cash over time. For example, one user writers that purchasing glasses online now costs about $40 as opposed to $275 at the common glasses stores, as a result of knowing his PD to go together with his prescription.
Remember that your near vision PD is generally 2mm to 5mm smaller simply because you somewhat cross your eyes when looking up close (Source).
If you are looking to purchase a pupilometer, reference our comparison table above make sure you are familiar with the warranty information of the particular unit you are interested in purchasing.