Luminance, Illuminance, Luminous Intensity
When analysing light sources one often wants to measure the luminance or illuminance of the source. Luminance is correlated to perceived brightness and expressed in candela per square meter whereas illuminance is the amount of light falling on a surface expressed in lux or lumen per square meter. The third covered unit which can be measured is luminous intensity [candela]. To measure luminance, illuminance or luminous intensity a different measurement setup is needed:
| Neo | Prometheus Viewfinder | Asteria | |
|---|---|---|---|
| Spectral color analysis | yes | yes | |
| Dominant & peak wavelength | yes | yes | |
| Luminance & illuminance | yes | Luminance | yes |
| Luminous intensity | Cosine corrector | Cosine corrector | Cosine corrector |
| Flicker | yes | ||
| Low luminance | yes |
How are you measuring?
With fibers and other accessories even more type of measurements are possible. Often used accessories are integrating spheres, cuvettes for fluids, light sources or filter holders.
A cosine corrector collects the light from the half space under 180 degrees. A typical application is the illuminance measurement of a lighting situation.
Consumers are used to enjoy top-quality displays in their mobile phones, tablets, laptops and even cars. Emerging technologies such as lighting surfaces for office and home illumination are expected to look equally perfect. Both displays and luminous surfaces are the main application areas for imaging colorimeters.
Measuring the luminance or color values at a specific location of the device under test is a typical use case when measuring displays. It can, however, also be meaningful to assess reflected light.
Viewfinder Spectrometer
Standard lens 1.2° spot ⌀ 4.56 mm ‑ 6.71 m
Viewfinder Spectrometer
Close up lens 0.75° spot ⌀ 0.96 ‑ 1.47 mm
Colorimeter 2.1 mm
0.001 - 30 000 cd/m²
Colorimeter 2.1 mm w/ pointer
0.001 - 30 000 cd/m²
Colorimeter 5 mm
0.001 - 30 000 cd/m²
Colorimeter 10 mm
0.001 - 30 000 cd/m²
Colorimeter 10 mm wide-angle
0.000 3 - 7 500 cd/m²
Colorimeter 20 mm
0.0003 - 7 500 cd/m²
Colorimeter 27 mm wide-angle
0.0001 - 2 800 cd/m²
Spectrometer
VIS 380 - 780 nm
High-End Spectrometer
VIS 360 - 940 nm