Scanning Retroreflectometer System

GL RETROREFLECTROMETER 4 SRS scanning retroreflectometer system

RETROREFLECTOMETER - to measure the reflective properties and color parameters of the illuminated surface

In accordance with the requirements of the CIE 54.2 and EN 12899 standards, manufacturers of reflectors and other reflective surfaces are obliged to test the reflection values ​​and determine the color coordinates of the illuminated surface.
GL RETROREFLECTOMETER 4.0 SRS emits light onto the reflecting surface and collects information about the reflected light, thus imitating situations when car lights illuminate e.g. road signs, and the reflected light returns to the driver’s eye.
Thanks to the use of a high-sensitivity monochromator, the entire measurement is extremely precise and takes only a few seconds!

Measurements in accordance with requirements of international standards

GL RETROREFLECTOMETER 4.0 SRS has been designed in accordance with the requirements of CIE 54.2, which describes possible methods of reflectance measurement. The GL Optic reflectometer allows you to perform tests according to the ECE R3, ECE R27, ECE R48 and FMVSS 10 standards, as well as in accordance with EN 12899 regarding the measurement of road signs.

Highest precision and wide measurement range

The A-type halogen illuminator (2856 K) used in the reflectometer allows for precise determination of color parameters. It is also possible to simulate other illuminants.
However, the fast monochromator guarantees constant and extremely fast measurement time and high sensitivity.

Full information about properties optical reflected radiation

The use of spectral matching filters may cause errors and negatively affect the precision of measurements. The lack of a spectral matching filter to the sensitivity of the human eye V(λ) in the GL Optic retroreflectometer translates into higher measurement precision, especially in the red and blue range.


GL RETROREFLECTOMETER 4.0 SRS is dedicated to work with the GLG A 50-1800 goniometer. The integration of these two devices creates a complete measurement system for car reflectors, warning triangles, road signs and all types of reflective tapes.
The basic use of a retroreflectometer is to determine the ratio of reflected light to the surface illumination intensity (CIL) and the x and y color chromaticity coordinates.

Fast monochromator expands possibilities

The GL Optic device stands out from competing solutions thanks to the use of a fast monochromator. This solution eliminated the need to use V(lambda) spectral correction filters, which avoids errors resulting from mismatching of the filter characteristics and enables the determination of photometric parameters for various types of illuminates based on measurement.

The use of a monochromator allows to expand the range of measurement results by a number of parameters determined on the basis of the spectral distribution of reflected light, as well as to analyze changes in the spectral characteristics of reflecting coatings.


Measurements in line with requirements and more

In accordance with the requirements of the standards, objects are tested in the H, V or H, V and epsilon axes in the case of road sign measurements.
In addition to the measurement of x, y color chromaticity coordinates required by the standard, the GL Optic retroreflectometer is also able to simultaneously measure many other color parameters.

Fast and reliable

The time of one measurement in the visible range is only 2 seconds!
The applied aging compensation system protects the device against a decrease in measurement precision resulting from the aging of the light source illuminating the tested surface.

More possibilities

Thanks to the use of the spectral measurement method, it is possible to test parameters also for illuminants of a different type than the default illuminant A.


Our preconfigured, individually calibrated instruments deliver fast and precise results for nearly any practical light measurement application. It enables to measure in seconds and review the results with the included software.

Using the GL RETROREFLECTOMETER 4.0 SRS, you can measure any or all of the following optical quantities:

    • CIL
    • Chromaticity cooridnates x, y
    • CCT – the color temperature according to standard CIE
    • Duv
    • Full spectral distribution in the visible range
      +many more!


Testing of automotive retro reflectors
Source typeQuartz halogen 275 W
CCT2856 K (Illuminant A)
Projector apertureø 50 mm
Uniformity of illuminance< 2%
Illuminated areaCircular with adjustable diameter by iris diaphragm ø from 20 cm to 70 cm (available at all working distances)
TypeScanning monochromator
Measurement time< 5 s
Entrance apertureø 12.5 mm
Spectral range340 nm - 780 nm
Spectral resolution5 nm
Angle of divergence αfrom 20' to 1°30' (0,33° to 1,5°) at distances from 10 m to 15 m
from 12' to 1°30' (0,2° to 1,5°) at distances from 15 m to 30,5 m (100 ft)
Angle position resolution0.0001°
Working distance10 m - 30.5 m (100 ft)
CIL measurement range1 mcd/lx – 10.000 mcd/lx
Uncertainty of colour coordinates0.0015
Dimmensions [H x W x D]2566 mm x 507 mm x 568 mm
Weight~ 50 kg

Note: Instrument, firmware and software specification are subject to change without prior notice. All information included in GL OPTIC datasheets and product information available in any form are carefully prepared and included information believed to be true. Please note that discrepancies may occur due to text and/or other errors or changes in the available technology. We advise to contact GL Optic before the use of the product to obtain the latest product specification.

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