Luminous flux is a measure of the total amount of visible light emitted by a source per unit of time. It is quantified in lumens (lm) and helps to describe how bright a light source appears to the human eye. This measurement is important in various fields, including lighting design and photography, as it allows for the comparison of different light sources. The concept of luminous flux is closely related to luminous intensity, which measures the amount of light emitted in a specific direction, and illuminance, which measures how much light falls on a surface. Understanding luminous flux is essential for creating effective lighting solutions in homes, workplaces, and public spaces.