LDN 500 Luminance Standard

The LDN 500 Luminance Standard is an ideal diffuse light source with an exceptionally homogeneous radiating surface. It is used for precise calibration of various optical detectors, such as CCD sensors, video cameras or conventional luminance meters.

LDN 500 luminance standard with control unit

A special advantage is the color temperature control of the LDN 500. After a few seconds, the standard reaches a color temperature of 2856 k (i.e. illuminant A), which is used as reference for the calibration of photometers. This feature distinguishes the LDN 500 from conventional, uniform calibration sources which only utilize simple luminance stabilization.

Excellent homogeneity of luminance is guaranteed through a large sphere diameter by comparison with the light emitting area.


  • Luminance standard comprising an integrating sphere with 500 mm diameter and 100 mm light emitting area; coated with barium sulfate
  • Stabilization of luminance and color temperature to illuminant A (2856 k); luminance level at illuminant A approx. 1100 cd/sqm
  • Adjustment range of luminance 200 to 2200 cd/sqm
  • Uniformity of luminance > 98% within a central circle with 90 mm diameter of the light emitting area

Ordering information

Order numberDescription
ACS-620 LDN 500 luminance standard, 500 mm diameter, with power supply and control unit FTR10-L; setting of luminance and color temperature