Horizontal Illuminance – Horizontal illuminance at a point is a measure of the lumens incident on the pavement divided by the area. The units are lumens per square meter (lux). … Vertical Illuminance – Measured in lux, vertical illuminance at a point is calculated on a plane 1.5 m above the surface of the road.
What is horizontal illuminance?
Horizontal Illuminace is the amount of light falling on a horizontal activity plane (also called workplane). Horizontal Illuminance in a Conference Room with electric lighting. … Notice the footcandle levels are highest in the center of the space, under the central luminaires.
What is horizontal and vertical illuminance?
The closer to a light source the illuminated area is, the higher the Illuminance value. Horizontal illuminance describes the amount of light landing on a horizontal surface, such a desk, and vertical illuminance describes the illuminance landing on a vertical surface, such as a wall.
What is vertical illuminance?
Vertical Illuminace is the amount of light falling on a vertical surface or plane. Vertical Illuminance on the projection screen in a Conference Room with electric lighting. … Notice the highest and lowest footcandle levels are indicated in red and blue respectively.
What is perpendicular illuminance?
Perpendicular illuminance: The perpendicular light which strikes on a horizontal surface. Perpendicular illuminance(Adaptive): The perpendicular light which strikes on a horizontal surface.
What is lighting uniformity ratio?
Uniformity is the ratio of the minimum lighting level to the average lighting level in a specified area. … A working environment with a 0.60 ratio is one in which people don’t notice different lighting levels with the naked eye and feel themselves in an environment in which light is well-distributed.
What do you mean by illuminance?
In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception.