Basic Information About Lighting

Space Angle

It is the name given to a conical or pyramid-shaped piece of space through which a certain luminous flux passes. The value of the space angle seeing the 1m² plane is defined as 1 steradian.

Light Distribution Curve

It is also called polar photometry. It is the geometric location of the endpoints of the light intensities of the source in various directions on the plane passing through a point light source.

Luminaire Efficiency

It is the ratio of the luminous flux from the luminaire to the flux of the light source in the armature. It is expressed by η.

Upper Half Space Luminous Flux Ratio

The ratio of the luminous flux emitted from the light source in a luminaire into the upper half space to the flux of the source. (ULOR)

Lower Half Space Luminous Flux Ratio

The ratio of the luminous flux emitted from the light source in a luminaire into the lower half space to the flux of the source. (ULOR

Degree of Protection

Indicates the resistance of lighting fixtures against dust, moisture, water and solid objects. It is shown as IPX1X2 according to international acceptance. X1 indicates protection against solid objects while X2 indicates the degree of protection against water. TS3033

Luminaire with Screen

They are luminaires whose maximum luminous intensity is limited to 60* with vertical and do not emit light to the upper half space (ULOR=0).

Semi-screen Luminaire

Luminaires whose maximum luminous intensity is limited to 75* vertically and do not emit more than 10% luminous flux into the upper half space (ULOR<=10%).

Screenless Luminaire

The maximum luminous intensity is not limited to a specific angle, but at an angle of 90* to the vertical