English Suomi

Goniophotometer Features and Accessories

Photometric Testing Solutions


High quality goniophotometers designed, manufactured and calibrated in Finland

High quality, ease of use, cost-effectiveness and professional support - SSL Resource provide you effective and trust goniophotometers to increase your competitiveness in the LED lighting area.

All our equipments are versatile and verified by reference measurements in the measurement standard laboratories in Finland and the Netherlands. We comply with the standards CIE S 025 and IES LM-79-08.

We provide goniophotometric testing and design solutions in different sizes for different kinds of needs. All inclusive measurement system with electrical and spectral options gives you

  • Spatial luminous intensity distribution (IES / LDT files)
  • Luminous flux and efficacy
  • Input power and power factor
  • Spatial color uniformity (SDCM)
  • Total correlated color temperature (CCT), color rendering index (CRI) and spectral radiant flux distribution

A goniometer gives you, what the integrating sphere gives, plus a lot more.

  • User-friendly measurement software
  • Laboratory space and construction costs saving solution
  • Reliable LDT/IES measurements in standard height rooms
  • All needed accessories: laboratory black material, sample holders, computer, installation and training service
  • Optimal gonio size for reducing transportation costs
  • Fast colorimetric measurements
  • Versatile measurement software


SSL Goniophotometer system has been developed for the measurement of light intensity distributions of different kinds of light sources. The goniophotometer consists of a goniometer, a photometer (or colorimeter instead as an option), a spectroradiometer (optional) and a power meter (optional). The SSL goniometers are several models for different size and type of luminaires. All gonio models are equipped with the similar gonio controller.

The SSL Goniometers of type C use the C-γ coordinate having the optical axis in horizontal direction. Thus the luminaire under test (LUT) is operated in horizontal axis. The C type goniometer is used in measuring SSL lamps, modules, and luminaires.

The B type goniometers, which use B-ß coordinates, are typically used in measuring automotive lighting and floodlights. More information about B type goniometer or please, contact us, we are happy to help you choose the right gonio for your needs.

The luminous intensity is recorded accurately by combination of a high quality photometer, or colorimeter/spectrometer and power meter with a feature of simultaneous measurement of photometric, spectral, colormetric and electrical parameters of the LUT. The measurement results are reported in standard file formats like IES and EULUMDAT for making possible the reliable 3D lighting simulation. Various lighting application figures like transversal/longitudinal isolux curves or cone diagrams are analyzed and illustrated automatically after measurements in the gonio program GPM.

Gonispectrophotometric testing system
Gonispectrophotometric testing system


The luminaire is rotated around the horizontal and vertical axis and at each position the photometric signal is measured at a fixed photometer location in the far field of radiation.

The C-plane is controlled by the horizontal axis. In each C plane, the angular luminous intensity distribution of the LUT is measured as a function of γ-angle by turning the LUT with the vertical axis.

The horizontal and vertical axes are moved with a sufficient angular step and range to reliably measure the angular luminous intensity distribution of LUT. The luminous flux can be reliably calculated by summing up all the luminous intensities from each measurement direction.
The SSL goniophotometers follow the CIE S 025 and IES LM-79-08 standards.

The principle of goniometer
The principle of goniometer


  • C type with horizontal optical axis (unless stated otherwise)
  • Stepper motors, worm gear drive system with deep groove ball bearings
  • Angular range of γ is ± 175°
  • Angle resolution < 0.01°, reproducibility and accuracy < 0.1°

Build up own goniophotometric laboratory - turnkey

Once your company is ready to handle light distribution measurements yourself, we will help you to get started and, if needed, take care of your needs comprehensively. Goniometer purchase will include the lab quenching materials, sample holders, metering computer and hardware installation. We will ensure the goniometer is installed properly, the lab room and the conditions meet the requirements, and your staff knows how to make measurements with the system. In the future, we can take care of maintenance and traceable calibrations when you focus on your core competence. Please, contact us to hear more.

Goniophotometers designed and manufactured in Finland.