Interference...

... of waves.

This 'photo is a continuation of a theme recently explored by @ViolaMaths.

In the early hours of today, 7 July, I happened to be wrapping something with 'holographic' film material. A bit of leftover film caught the light from my desk light, and I was impressed by the effect produced by this entirely fortuitous arrangement of light source and diffraction grating.

I thought I would have a go at capturing the nice range of colours, and that's about all I can say.