blue light shield computer reading/gaming glasses for kids- 0.0 magnification - anti blue light 90% uv protection low color distortion, classic black and green frame - essential gaming gear (tk4002c1) kirka <b>★protect your window of soul</b><br> kirka computer glasses will keep your eyes safe from all harmful blue light, designed for anyone using any electronic device such as computers, tv or phones.<br>effectively reducing eye strain and headache, relieving eye fatigue and dry.so you can enjoy a restful deeper sleep.<br><br> <b>★what percentage of blue light does our computer glasses block? </b><br> kirka computer glasses focuses on blocking off the high-energy blue/violet spectrum (400nm - 430nm). <br>this is the most harmful part of the light spectrum and is the part that we are blocking the most - at 90%. <br>we then let through more of the low-energy blue spectrum (430nm - 495nm). <br>it is relatively less harmful compared to the high-energy blue region and only 30% of light in this region is blocked so you can still see most blue as blue through our glasses. <br>this is why we can achieve a low color distortion characteristics for our lens. <br><br> <b>★blue light blocking test</b><br> step 1.you will get a test card and blue light flash when you buy kirka computer glasses.<br> step 2.the white area of the test card will turn to purple when it exposes to blue light. using blue light flash to beam the white area , the white area turn to purple.<br> step 3.when using blue light flash to beam the white area through kirka computer glasses, the white area don't change color. that means kirka computer glasses can greatly block the harmful blue light.<br><br> <b>★includes</b><br> 1*computer glasses<br> 1*cleaning soft cloth<br> 1*glasses pouch<br> 1*blue light test set<br> 1*box case<br>