Large Light Source Performance Characterization System

PM-NFMS™

Typical Applications

  • Near-field luminance distribution models for large light sources
  • Generation of illumination distributions for large light sources in a compact space
  • Illumination modeling of automotive and other headlamps
  • Illumination modeling of room and architectural lighting systems

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Comprehensive view angle performance characterization system for large light sources

The PM-NFMS™ system performs brightness and color measurements as a function of viewing angle for large light sources. It is designed to provide accurate near-field luminance distribution data for developers of large light sources, for automotive, transportation, architectural, and other applications. Because the PM-NFMS system captures a complete near-field model of the light source, it provides much more comprehensive information — in a much smaller measurement space — than can be obtained from traditional spotmeter-based measurements.

PM-NFMS is a complete, automated system for large light source measurement and analysis

The PM-NFMS system consists of a PM Series™ Imaging Colorimeter, a two-axis goniometer for precisely adjusting the display’s angular position relative to the imaging colorimeter, and PM-NFMS software that controls both the imaging colorimeter and the goniometer during the measurement sequence. The PM-NFMS software also includes a comprehensive set of data analysis tools.

The PM-NFMS control and analysis software automates the measurement functions of both the PM Series Imaging Colorimeter and the NFMS goniometer, allowing definition and execution of a complete measurement sequence with minimal effort. The measurement data is preserved as a set of display images, capturing an image of the light at each viewing angle as a Radiant Source™ Model (RSM). The RSM can be analyzed directly to understand light source performance, or Radiant Imaging’s ProSource software can be used to convert the RSM to a ray set for use in leading optical design software packages.

Extensive display analysis functions provide complete view angle performance analysis as well as extrapolation as an illumination distribution

The PM-NFMS system software supports light source performance analysis through an extensive variety of quantitative analyses, including isoplots, CIE color analyses and radar plots. In addition, the PM-NFMS software can be used to extrapolate a far-field illumination distribution from the measured near-field RSM. Because the illumination distribution is derived from the near-field data, this results in a substantial reduction in the space required to perform these measurements when compared to spotmeter-based methods where the measurement instrument must be place in the far field. The spotmeter cannot provide near-field data either.

Multiple hardware configuration options fit any application

Any PM Series Imaging Colorimeter can be selected for use in the PM-NFMS system; the ultimate selection will be a function of the dynamic range, measurement resolution, and field of view required. The NFMS goniometer is available in several sizes to support varying light source sizes, ranging from headlamps to architectural lighting systems.