Radiant develops integrated solutions for both R&D and production-line testing of intensity, illuminance, luminance, and chromaticity of various lighting sources. In R&D environments, compact goniometer systems combine imaging technology and application software to deliver fast, cost-effective, and comprehensive data, enabling lighting engineers to optimize their product designs and easily generate standard output files, including IES, EULUMDAT, or Radiant Source Model® (RSM) formats. On the production line, our test systems ensure product quality and consistency in real time, optimizing cost-efficiency and increasing yields.
LED Source Characterization
The physical structure of LEDs is more complex than most lamp sources. Accurate source models produced during the design of an LED-based system enable lighting engineers to achieve the desired performance of their design and verify correct assembly in production.
Radiant’s integrated systems are comprised of an imaging colorimeter and precision goniometer with dedicated software to capture complete and precise data to characterize light source output. This data can then be used for design evaluation and imported into any major optical design package, such as ASAP®, FRED®, LightTools®, LucidShape®, Photopia™, IES TM-25, Opticad®, OSLO®, SimuLux®, SPEOS®, TracePro®, and OpticStudio™ (ZEMAX), as well as general file formats like IES or EULUMDAT.
Luminous Intensity Distribution Measurement
The output of an LED as a function of angle is its luminous intensity distribution, a measurement with critical implications for the quality and usability of the LED. Luminous intensity distribution describes the directionality of the light output and the power of light in each direction from the LED.
A key step in the production of encapsulated LEDs or LED-based optical assemblies is the alignment of the optics to the LED die. Improper alignment will alter the output of the LED—the angle and intensity of light emitted from it—and will impact the overall performance of the system in which it is used. Our goniometric systems acquire complete luminous intensity data for all output angles from a source LED, enabling designers to define an objective standard for optimal system performance, and to ensure that standard is maintained in production.
Color and Brightness Testing in LED Arrays
LED arrays are found in a wide range of lighting products, including indicator lights, signage, and backlights. Our high-precision measurement systems help design engineers accurately characterize their product designs. They also test color and brightness for quality assurance in high-volume manufacturing operations. The nearly-monochromatic output of most LEDs has historically made it difficult to acquire accurate color and luminance measurement using systems based on color filters. Radiant's systems combine highly-accurate filters with our patented ProMetric® Imaging Colorimeter calibration technology to yield accurate chromaticity measurements while delivering the benefits of a CCD-based system. Our imaging colorimeters can also measure hundreds or even thousands of LEDs simultaneously.
View Angle Performance Characterization in Large Light Sources
Developers of large light sources for automotive, transportation, architectural, and other applications need to generate luminance distribution data for performance analysis, illumination modeling for lighting systems, or for manipulation in optical design software packages.Radiant light measurement systems gather data that qualifies the accuracy of luminance (brightness) of a source in angular space, as well as illuminance to determine the scope and spread of output to ensure areas are lit as intended, with accurate power in each direction.
Radiant’s ProMetric Near-Field Measurement System (PM-NFMS™) is a goniometric system for large light source measurement and analysis. It measures brightness, color, CRI, and spectrum as a function of view angle by capturing a complete near-field model of the light source. Mounted to the PM-NFMS goniometer, a large light source is rotated in several directions in front of a ProMetric Imaging Colorimeter, mounted 1-3 meters away on a tripod. The imaging colorimeter acquires measurement data for every rotation to build a model of the light source in three-dimensional space. This solution delivers comprehensive data from a very compact system, supporting an extensive variety of analyses, including extrapolating far-field illumination distribution from the measured near-field data. Using near-field methods to extrapolate data, the PM-NFMS can be used in labs as small as a few meters, reducing the space needed for far-field data analysis (usually 15 meters or more).
Source Imaging Goniometer® (SIG 400)
ProMetric Near-Field Measurement System (PM-NFMS)
White Paper: Efficient Measurement of Large Light Source Near-Field Color and Luminance Distributions for Optical Design and Simulation
On-Demand Webinar: Creating IES Files for Luminaires and Lighting Fixtures
On-Demand Webinar: Improving Color Measurement Accuracy for LED, Luminaire, and Display Imaging