New filter creates colours based on incident light's angle
US-based researchers have developed a directional colour filter with non-uniform grooves that transmits incoming white light at red, green, and blue wavelengths when it is incident at 0Âº, 10Âº, and 20Âº respectively. However, white light incident at any angle on the non-patterned side is separated into all the three colours, each being sent off at the same respective angle.