Reflexion measurement of displays
specbos 1211L and spectraval 1501 can be used for reflexion measurements, if an illumination source and a set up realizing the appropriate measuring geometry will be added. An example is the measurement of display reflexion, as described e.g. in the Information Display Measurements standard¹.
An integrating sphere with lamp(s) illuminating its interior is used to create a homogenious and diffuse illumination of the display, which is mounted in the centre of the sphere. The measurement can be done with specular reflex uncluded or excluded. The angle θd is normally 8°.
The following measurements are performed with switched on display:
- Measurement of the display Luminance when illuminated by the sphere illumination (LQon)
- Measurement of the reflectance standard Luminance when illuminated by the sphere illumination (LstdQon)
- Measurement of the reflectance standard Luminance without sphere illumination (LstdQQoff)
- Measurement of the display Luminance when sphere illumination is off (LQoff)
The resulting reflectance ρ8/di (specular reflex included) and ρ8/di (specular reflex included) will be calculated as follows:
¹Information Display Measurements standard. IDMS/ SID. www.icdm-sid.org