Applications of JETI Spectroradiometers specbos 1211focus

Measurement of Alphanumeric and Symbolic Displays

The main application for light measurements in Luminance mode (directed measurement) are extended homogenious light sources as monitors or cinema projections. Sometimes it is of interest to measure small spots or structures, e.g. the symbols on illuminated control switches or alphanumeric displays.
Radiometers can be equipped with a focusing optics creating a measuring spot of 1 mm diameter or smaller.
specbos 1211 in its basic configuration can measure Luminance only in spots of 4 mm diameter and more. Three focusing optics for measurements with 3 mm, 1 mm and 0.5 mm diameter are available. The measuring spots are marked by a red circle. The 0.5 mm version is fitted out with a magnifying glass to simplify the precise adjustment.
All add-ons can easily be attached to the basic instrument by screwing. The version is automatically detected and the appropriate calibration data will be applied.
Measuring objects:
  • Alphanumerical and numerical displays
  • Fluorescent tubes with small diameter
  • Backilluminated signs
  • Other small light sources
Focusing Optics #1 #2 #3
Measuring diameter 3 mm 1 mm 0.5 mm
Measuring distance 70 mm 26 mm 46 mm
Field of view 2.1° 1.9° 0.6°
Length 77 mm 26 mm 77 mm
Part number ACC 006 ACC 007 ACC 008


The attachment optics cannot be used with a standard specbos 1211, therefore they have to be ordered together with a new instrument.