5 things to consider buying Blue Light Glasses
5 things to consider when shopping for Prescription Blue Light Glasses
13 August 2020
With the current stay at home climate, the eyewear industry has seen a surge in demand for blue light glasses that promote good sleep, reduce eyestrain and protect against harmful radiation from mobile and computer screens. Prescription Blue Light Glasses not only correct vision, but also offer this same protection.
But with the market awash with blue light protection marketing messages, what are the pitfalls? Will they work, and what type of blue light glasses do I need?
A quick google search will find you online tests to ‘test’ your blue light glasses (if you see this colour, your glasses do not block blue light...), you’ll find tests to purchase (shine this light through the lens, if the paper turns blue, your glasses do not block blue light...) - and you’ll find vendors offering “100% Blue Light Blocking”. Which sounds perfect - for those who never want to see the colour blue again.
Where is the truth, what are blue light blocking glasses, and which ones do I need?
There are some home truths about blue light glasses that should be laid bare that this article will attempt to justify:
- Not all blue light is bad
- Computers and mobiles are NOT the only source of blue light
- Certain blue light is essential to good health and vision
- You do not need to eliminate the colour blue to protect against harmful blue light
- Blue Light Glasses do not necessarily need a Red or Yellow Tint
The above statements may contradict a number of marketing messages out there. So to back this up, allow me to explain...
Blue Light and the Visual Spectrum
To first understand if your blue light glasses work, it might be worth outlining what blue light is and why it’s bad.
The light spectrum is made up of energy measured in nanometers, the lower the NM number (shortwaves) means more energy, more harmful to the human eye.
It starts with UltraViolet Light, which is invisible to the naked eye - but harmful, Violet, Blue then all the way to Red and Far-Red.
To briefly summarise:
The above diagram outlines the cross over from harmful Sun light - up to UV400 (400nm), harmful Blue light (380nm to 440nm) and visible blue light (380nm to 500nm).
Studying the diagram, you’ll work out that ‘Visible Light’ is made up of all colours from violet to far-red, and you’ll see the portion of it that is ‘Blue Light’, and the portion of it that is considered ‘Harmful Blue Light’
Why is this important?
Harmful blue light is at the beginning of the Visible Blue Light Spectrum. Around 37.5% of Visible Blue Light is considered harmful.
Blocking light between 440nm and 500nm will be detrimental to your vision (you see less of the colour blue), and won’t provide any further protection against harmful blue light (which stops at 440nm). Therefore, blocking 100% of blue light kind of seems pointless, if only 37.5% is the harmful light we're concerned about...
Blue Light for Vision and Good Health
Blue Light is important because it is one of the primary colours that make up our vision.
Blocking the entire Blue spectrum with Blue Light Blocking Glasses will essentially ‘colourblind’ the wearer from the colour blue.
This by any measure, is a stretch too far to protect against the dangers of blue light. Instead, it would be far better to block out just the right amount of blue light that will have minimal impact on the quality of your vision.
Blocking all blue from your vision will have big time implications:
- Unsafe for Driving - you will need to see the colour blue (e.g. ambulances, police cars) to be considered safe on the road. Blue Light Blocking Glasses that block 100% of blue light, are not considered safe for driving
- Negative effect on sleep - Blue Light is essential for regulating the natural body clock. Blocking 100% of Blue Light will have long terms effects as to how your body reacts to light and the natural body clock
- Colour Blindness - Why would you like to cut out the colour blue anyway? It’s a beautiful colour! You should have the protection you need without compromising your vision
Another consideration is European Standards CE Certification. Sunglasses have to conform to CE certifications that ensure close to 100% of UVA/UVB (up to 400nm) light is blocked.
The certification also requires sunglasses are safe for use for general purpose; which includes driving a car.
Therefore, Blue Light Blocking Glasses that block out 100% of Blue light, may not be certified to European standards, and if they’re not certified, this means they have no liability to ensure 100% UVA/UVB protection either.
Different Ways to Block Harmful Blue Light
There are essentially two ways to block harmful blue light on eyewear;
Tint - the traditional way would be through dyeing a lens amber or red, which blocks the sufficient amount of blue light
Tinted Red of Amber Lenses offer blue light protection - arguably more blue light protection than a coating alone. Tinted lenses work by adding a dye to the lens, which is formulated to change the view to reduce or remove the blue light from view.
A full on Red or Amber lens will potentially block out 100% of Blue light, but will sacrifice your ability to drive a car, read blue writing or enjoy the sunrise! You will be limited to computer use, and even then certain games will be unplayable if they happen to use the colour blue a lot. A coating will protect against harmful blue light, but will also allow you to use your lenses for day to day stuff as well. Protection and convenience.
Coating - In as late as 2007, new technologies were developed to block blue light via a near clear coating, rather than a full-on tint. This ensured vision would not be impaired, whilst blocking out the sufficient levels of harmful blue light.
Coating works by nanoparticles which react to certain wavelengths in the blue light spectrum.
This advanced technology causes the lens to ‘absorb’ the blue light at the lens layer. The result (for better or worse) is there is a blue reflection on the outer side of the lens - this essentially means the coating is doing its job! Some wearers may not like this ‘blue hue’ on their lenses, but alas, this is the price you pay for protection!
Fitzgerald Blue Light Frame: Made with Walnut Wood and Ebony
How to tell if my glasses have blue light protection?
The easiest way to test if your glasses have blue light protection, is to simply hold it up to a blue light source - e.g. the sunlight.
Compared to standard non-blue light lenses, you should see an actual blue reflection on the lenses. This is the blue light coating doing its magic:
How much Blue Light Do FreshforPandas Eyewear Block, and what else do they do?
With FreshforPandas Blue Light Glasses you get
- Up to 100% UV400 Protection
- Over 60% of harmful blue light blocked (tested to 78.90% transmission of tsb (380nm to 500nm)
- Safe for general use; driving, outdoor use as well as indoor use
- CE Certified and independently tested
- Blue Resist Coating technology: with a slight yellow tint
- Plastic Free Packaging
- Foldable Cork Carry Case and Adjustment Screwdriver
- Microfibre Cloth, Cloth Pouch
- A clear conscious: Eco-Friendly frames made from natural materials
That sounds great! I really want a pair, can I buy online?
Oh, I’m glad you asked :) Our Blue Light Collection can be found here, if you have any questions, please do pop us an email or use our live chat!