I know that white light, upon entering another medium from air/ vacuum, disperses into its constituent colours. Essentially when travelling in the air, all of the constituent colours have the same speed but when entering another medium, they travel with different speeds and hence they are refracted by different amounts - red the least and violet the most among the seven colours. So we are able to see the constituent colours (especially in the case of a prism since they are diverging.)
But I came across the following situation where green light (mono-chromatic) changes into red, as perceived by the human eye as well as the camera. Attaching an image of what happens:
Why does this happen? I am a high school student and I haven't read anything so far that could explain my observation. Also as far as I know the properties of light are dependent on its frequency and frequency does not change from medium to medium.
I saw the other posts but it would be nice if someone explained it in a much simpler language.
