Application of JETI Spectroradiometers specbos and spectraval

Light Measurement in Laboratory 

The following four basic quantities exist in light measurement:

 

 

  Quantity

 

Symbol

 

  Unit

 

Simplified definition

 

Used for characterization of

   

   Luminous flux

 

 Finu

 

lm

 

 

Halogen lamps, LEDs ("optical power" into all directions)

 

   Luminous intensity

 

 Inu

 

cd
(basic unit)

 

 InuForm

 

Point like sources as LED and lamps with reflector

 

   Luminance

 

 Lnu

 

 cd/m2

 

 LnuForm

 

Homogenious sources as monitors and video walls

 

   Illuminance

 

 Enu

 

  lx

 

 EnuForm

 

Light intensity » in a certain plane

For an extended scheme see Application Note 20.

 

The spectroradiometer specbos includes different models which allow to measure all these four quantities based on the spectral resolving technique. This universal system covers all spot measurement applications in the lab and is therefore best suited for a general use.
Besides the photometric data and the spectrum also the radiometric and colorimetric data are obtained.
The basic unit specbos 1211 allows to measure in luminance and in illuminance mode and ordered with various accessories. specbos 1311 adds luminous flux and specbos 1411 luminous intensity.
The new spectroradiometers spectraval measure the spectral radiance and in addition to the radiometric and photometric values the colorimetric values x, y, color temperature, color purity, dominant wavelength and the color rendering indices are determinable.

 

specbos 1211 bt
 

scv1501

 

specbos1311 300

 

 

 

specbos 1211-BT
 
spectraval 1501
 
specbos 1311
 
specbos 1411
 

 

Furthermore the luminous intensity of a source can be measured using the illuminance mode of specbos 1211 (see application: Radiant intensity calculation using irradiance measurement).