ILLUMINATION LEVEL MEASUREMENTS

YFU makes instantaneous and continuous illuminance measurements with well developed, portable instruments.

Instantaneous illuminance measurements are made to see the quick fluctuations of illuminance which are caused by the conditions right at the moment of measurement. In this mode, the measuring instrument can be connected to an oscilloscope to watch the real-time changes in illuminance.

Illuminance measurements, are made usually for a fixed (at factory) time interval (gating) and giving the average illuminance of this period. On the instrument used in YFU, this gating time can be selected between 0.1 and 10 seconds with intervals of 0.1 seconds. With any selected averaging time it is possible to make either independent single measurements or to make continuous measurements. It is also possible to have a direct readout of mean, maximum and minimum illuminance for a certain number of measurements done.

The illuminance transducer is corrected to the CIE standard photometric observer.

Illuminance measurements which can be made are :

planar illuminance (with cosine correction)
Measurement of the illuminance on a plane surface. By this measurement, the position of the surface and the side on which the measurement is made is indicated.
These measurements can be done in a range from 0.01 lx to 200,000 lx (lux = lm/m²).

semicylindrical illuminance
It is a measuring technique where the illuminance on the half of the side surface of a cylinder with its axis vertical is measured. This technique is usually preferred for the measurements in stages, podiums, sport fields, photography etc. to determine the semicylindirical illuminance on human body.

hemispherical illuminance
This is a measuring technique to obtain the illuminance on the upper half of a sphere. This technique is generally used to measure the illuminance on three dimensioned structures which are situated in open-air.

With the above mentioned various illuminance measurement techniques, every need of illuminance measurement can be met.

For comments please send an e-mail to Osman Sirel.