How To Test Blue Light Glasses - Part 2

✓ Medically Reviewed by Jack Cincotta

how to test blue light glasses part 2


If you have not read part 1 then you should read that article first. You can do that by clicking here.


Following on from my initial article on how to test blue light glasses several common questions came up from our amazing readers that I felt needed addressing in a part 2 special.


Even from my last blog on how to test blue light glasses it appears that there is still a lot of misinformation and lack of understanding on why we need our blue light glasses to filter specific frequencies. There is also a lot of confusion over lens colours and which blue light glasses are required for different points during the day. Not all blue light glasses are created equal and you can try some of the at home tests to determine whether you are blocking blue light correctly for the lenses you have purchased.


Testing blue light glasses is more necessary now than ever before as many brands have cheap prices but their blue light glasses at worst do not block any blue light and at best block the wrong frequencies of blue light.


Below I will address some of the common questions that came about from my blog on how to test blue light glasses. This way you will be empowered with the knowledge to manage blue light correctly.


What Blue Light Glasses Do I Need?


This question is a common one as when testing blue light glasses, we first need to understand why there are different types of lenses that manage blue light.


Daytime – Clear Lenses


During the daytime it is paramount to NOT block blue light. Blue light is essential during the day. What colour is the sky? Blue! But there is a lot of blue light from artificial sources indoors during the daytime.

To manage this one needs to filter blue light, not block blue light. Filtering blue light can be done using a clear lens with a blue light filter added. To test this are your clear glasses reflecting blue light when you shine artificial blue light onto them? If the colour reflected is green or a deep purple you are not wearing the best blue light glasses. The best blue light glasses will reflect blue light and the colour of the reflection will be blue.


Using the test strip or colour circles test on clear lens computer glasses will not work, they do not and are not meant to block blue light.


Night Time – Deep Orange/Red Lenses


After sunset you must block 100% of blue light and also most green light. The range of light you need to block is 100% between 400-550nm. This is all blue light and almost all green light.

The biggest misconception with people is that they can wear clear computer glasses to block all blue light in the evenings. A clear lens cannot block 100% of blue and green light between 400-550nm, its just not possible, yet.


Companies use marketing tactics saying “no more ugly red or orange lenses, use our clear lenses instead”. You could use them, but when you test these blue light glasses they will not be blocking blue light.

Red lenses such as Blue Light Blocking Glasses from BON CHARGE are the best option.


But, Wont Everything I See Be Red?


When you wear your BON CHARGE Red Lens Blue Light Blocking Glasses after sunset and block 100% of blue light and most green light colours will change. If you block a colour you won’t see it and that is true for blue light. The best blue light glasses will not turn everything red. When you wear the best blue light glasses then you see blue as black and greens as lighter greens. The best blue light glasses WILL change colours, but not make everything turn red. You know when you do not have the best blue light glasses as their lenses will make everything appear red or you will be able to see blue light which renders them useless.



I Have a Blue Light Emitting Pen that shows BON CHARGE Computer Glasses Do Not Block Blue Light.


This is also a common question when testing blue light glasses. I covered the blue light pen test in the last blog but I will cover it again. The little blue pen that came with your mass produced “computer glasses” does not emit blue light! The pen emits a very narrow band of purple light, which is unsurprisingly the exact narrow band of purple light the glasses you have just purchased, block. Remember, you need to filter blue light during the day when using the best computer glasses, not purple light. Purple light is not the issue, blue light is.


So why does the blue light pen test not work on BON CHARGE Computer Glasses? The reason is these computer glasses, the best computer glasses, filter blue light, not the purple light emitted from the pen.


I Can Still See Green Light Through BON CHARGE Red Blue Light Blocking Glasses Lenses.


That is correct and means they are working correctly. Many people wrongly assume that you must block 100% of both blue and green light after sunset. 

You must block 100% of blue light, that is a given. You then must block 100% of the green light found between 500-550nm as well. Green light runs from 500-580nm. The reason you can see some green light wearing the best blue light glasses from BON CHARGE is that we do not block all green light, we block all light between 400-550nm which is 100% of blue light and most green light.


Can I Wear Red Lens Blue Light Glasses During The Day?


Another question that seems to frequently arise is can one wear the best blue light glasses, Blue Light Blocking Glasses (red lenses), during the day. When testing blue light glasses we know that we must only filter blue light during the day and block it after sunset. Our light needs change from day to night so you cannot simply have one pair of blue light glasses. In order to have the best blue light glasses you must have two pairs, one that filters blue light during the day (computer glasses) and one that blocks 100% of blue light after sunset (blue light blocking glasses).


Final Thoughts


In the ocean of misinformation on blue light glasses we want to ensure everyone has access to the facts, not a marketing plan to get you to part with your money.

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