A diffuser is any material or device designed to scatter or soften light, reducing harshness and creating a more even illumination. Common examples include softboxes, translucent fabrics, frosted glass, or plastic panels.
The effect of a diffuser is to soften shadows, reduce glare, and produce gentle, flattering light on the subject. In photography, the position of the diffuser relative to the light source is important: the closer it is to the source, the less the light spreads, producing a more controlled soft effect. Diffusers are widely used in portrait, product, and studio photography to create professional, visually appealing images.