New iPhone App solves worries about PD when buying glasses on line
2011 has seen the dawn of a revolution in the history of the new craze for buying prescription glasses on line. It is all thanks to the industry leading technology giant, who we all know and love as ‘Apple’.
When buying prescription glasses on line there is one piece of information often missing from the prescription details that your optician will have given you after your eye test, your Pupillary Distance. Although the law may change, at present the Puillary Distance is not classed as part of your prescription legally required to be provided. Pupillary Distance (P.D) is the measurement between the centre of the pupil in one eye to the centre of the pupil the in other eye.
Although there are some very simple ways to overcome your optician holding back from supplying your (P.D) such as measuring the distance yourself with a ruler in the mirror or sending your old glasses into the retailer that will be making your new glasses, to obtain the P.D from your current lenses. There is now a high technical industrial leading way to measure your own P.D that will be extremely accurate and can be done in a matter of seconds. This will ensure that you can purchase perfectly fitting glasses online with confidence and an added bonus of saving a huge amount of cash.
The iPhone and iTouch P.D measuring App, called the Pupil Meter was created by an optometrist from Denver, USA. A Google Android and iPad version of the Pupil Meter are currently being worked on and is due to launched in the next few months.
So, if 
How to use the Pupil Meter App
The person having their P.D measure should focus on the iPhone camera. If the person wears contact lenses or glasses they must keep them on.
Hold any regular sized credit card under the nose, with a black strip on the back facing forward as if it were a moustache. You can use any type of credit card sized card such as gift card, driving license or any debit card.
The person taking the photo should hold the iPhone camera 2 feet (60cm) away from the person holding the credit card and focus the photo at eye level, using the bridge between the persons eyes as the central focal point. The person having the photo taken for the P.D measurement should hold head in a comfortable, relaxed position and look straight ahead at the iPhone.
After the photo has been taken, touch the black strip on the card in the photo, this will prompt a box to appear around black strip of the credit card in the photo. Adjust the green edges of the box to fit around the credit card exactly. When the green box is locked on the black strip, the pupil measurements can be taken.
Move the cross lines over the centres of each of the pupils. The P.D measurement will clearly display.
To ensure a good picture is taken make sure you are in a area with good, natural light. Bright lighting may cause the person to squint which may affect the P.D measurement produced. For the best results take three consecutive photos and measurements. If you take the average of all three this will be the most accurate result. Your P.D reading will be accurate if there is no more than 2mm difference between all three photos P.D readings.
The technology doesn’t stop there! Opticians themselves are taking advantage of the accuracy of the Pupil Meter App’s from Apple. The Pupil Meter Pro for the iPad is being used by professional optometrists across the world to measure far P.D as well as both Binocular and Monocular, seg height and optical centres.
If it’s good enough for the professionals therefore it more than good enough for us! Go and measure your P.D and buy your new glasses with confidence on line.
Direct Sight are a leading online optician, selling a wide range of eyewear including varifocals lenses. They deliver the prescription glasses direct to your door.