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The system is constructed for measuring light sources with a maximum diameter of
100 mm. It is calibrated with the help of a calibration source with an aperture
diameter of 35 mm with constant field of light output. Thus, subsequently measured
light sources with the same aperture and a constant field will have an error of 0%,
whereas light sources smaller than 35 mm will have a positive error and vice versa.
The errors can occur due to differences in sizes of apertures of light fixtures. The
largest error is then calculated according to the minimum and a maximum aperture
sizes.
Max positive error +0.49%
Max negative error -2.55%
In most cases the maximum error would be smaller than 2.55%, as the light radiated
from a large aperture would be highest in the center.
The inaccuracy of the sensor is rounded off to < +/- 2%.
Sensor intensity error < +/- 2%
Circular field accuracy
The LightSpion measures the luminous flux in lumen, which accounts for light
radiated in all directions. Lumen measurement is generally done with the help of an
integrating sphere, which allows to collect light radiated in all direction into one
point.
The LightSpion uses goniometer technology to obtain this measurement. It captures
light from one section of the light source and afterwards calculates the complete flux
value based on this section, as shown below (section “A” is presented in green).
