Products, Materials + Tools | Mar 20, 2012

Ideal Measuring System for Mid-Sized SSL Luminaires and LED Modules

Instrument Systems, the global market leader for LED metrology, launches a new measuring system for Solid-State Lighting applications with the LGS 250 goniophotometer.

The LGS 250 was developed specifically for the analysis of angle-dependent spatial radiation properties from small to medium-sized SSL luminaires, lamps and LED modules. This closes a gap with the very large goniometers. The horizontal alignment of the Type C coordinate system facilitates a particularly convenient and compact test setup for the system. Measurements can be taken in a range of +/- 160° in the forward direction of the test specimen which may have a maximum diameter of up to 480 mm and a maximum weight of 8 kg.

Combined with a spectroradiometer from Instrument Systems, all spectral quantities such as color coordinates, color temperature, and color rendering index can be determined as a function of angle. C-plane measurements can also be carried out very quickly “on the fly” using the Optronik DSP Photometer. The LGS 250 is supplied in two versions as a goniometer with a stable base and integrated LGS Controller, and as a benchtop version with separate 19” rack for the LGS Controller.


  • Type C goniophotometer with horizontal optical axis
  • For samples up to 480 mm diameter and 8 kg weight
  • Accurate determination of the luminous intensity distribution and luminous flux
  • Angular-resolved analysis of spectral and colorimetric quantities
  • Data export in IES and EULUMDAT format


Technical specifications: LGS 250 Goniophotometer


CIE goniometer type

Type C with horizontal optical axis


Stepper motors

Angular range C axis

± 160° with reset switches

Angular range Gamma axis

± 160° with reset switches

Resolution of the angle encoder


Reproducibility C axis

≤ 0,1° (at max. sample load)

Reproducibility Gamma axis

≤ 0,05° (at max. sample load)

Angular speed C axis

16 speeds selectable to maximum 25°/s

Angular speed Gamma axis

16 speeds selectable to maximum 14°/s

Clear width

250 mm

Sample table

Maximum sample size

480 x 140 mm² or 440 x 235 mm² or 350 x 350 mm² (in each case for symmetrical mounting)

Maximum sample mass

8 kg

The SpecWin Pro software supplied permits convenient and efficient analysis of the measured data with a range of display options. The measured data obtained can also be exported in IES and EULUMDAT format. The LGS 250 is also compliant with all the relevant specifications in conformity with CIE, DIN and IES standards.

For additional information please visit the LGS 250 microsite or contact Instrument Systems at

About  Instrument Systems:
Instrument Systems was founded in 1986 and is based in Munich. The company develops, manufactures and markets turnkey solutions for light measurement. Instrument Systems delivers a comprehensive range of light measuring products for industrial and research applications. These include high-performance array and scanning spectrometers as well as imaging photometers and colorimeters. Key applications are LED and display measurement, as well as spectroradiometry and photometry. Instrument Systems is one of the leading manufacturers for spectral light measurement systems. The innovative measuring systems from the Munich company deliver accurate and reliable results for all optical parameters of light sources in conformity with CIE recommendations. Instrument Systems provides support for the global customer base with backup from a comprehensive network of representatives.