The band of light obtained on a screen, typically from a source like a laser or a slit, is called a diffraction pattern.

Here's a breakdown of the different elements:

* Diffraction: The phenomenon of light waves bending around obstacles or spreading out as they pass through narrow openings.

* Pattern: The specific arrangement of bright and dark bands observed on the screen.

The specific type of diffraction pattern depends on the shape of the obstacle or opening, and the wavelength of the light used.