In fact, the principle is very simple: add a filter in front of your eyes
put on a pair of glasses, colors that are difficult for ordinary people to distinguish with the naked eye, you can also easily distinguish, do you want to try?
what is shown in this picture is the comparison between the lenses of this kind of glasses (the two above) and ordinary lenses. Two similar colors can be seen in the background. The difference between them can be made very clear at a glance.
most people's eyes distinguish colors through three types of cones. Human beings can recognize many different colors, but there are still some shortcomings. For example, there will be a phenomenon of "metamerism": the spectrum that makes up the color is different, but it is impossible to distinguish it from the human eye.
and this pair of glasses is designed for this situation. With it, colors that look the same to the naked eye can be clearly distinguished.
how is this done? In fact, it is also simple to say that the glasses on both sides are filters, which can filter out different bands in the visible spectrum.
my understanding is like this: for example, for human eyes, red light and green light can produce yellow together, while there is also a monochromatic light that is really the yellow wave band, which may just look the same. At this time, if you choose a band to filter out (for example, the band that filters out green light), there will be a significant difference in the effect of red-green mixed light and pure yellow light on human eyes.
this can be done with only one filter, but it has a side effect: it may make two different colors look the same through the filter, in order to counteract this side effect, you have to add a filter with a different band to the other eye.
A schematic diagram of the original text:
researchers believe that with this pair of glasses that improve color resolution, new anti-counterfeiting methods can be developed, and they can also be used to see through some visual camouflage.
What you see is no longer the original color _ (: colors "∠) _
PS: there are also a small number of women who naturally have" four-color vision ". To learn about this, you can read the original article.