Radiant Imaging unveils luminous intensity tester

Radiant Imaging's new IS-LI is said to be the first system to enable rapid, comprehensive measurement of the luminous intensity of LEDs and other small light sources. Based on patented integrating sphere technology, the IS-LI acquires luminous intensity (brightness as a function of angle) data over an entire 2π ?steradian in a single measurement, taking just seconds or less, the company said.

The system promises up to 16bit luminance measurements, with an angular resolution of 1 percent or better. Alternately, the device can analyze color versus emission angle, a particularly important performance metric for "white light" LEDs. Obtaining these precision measurements previously required goniometric tools. With no moving parts, the new device is orders of magnitude faster than traditional methods, the company said, and is also substantially more economical. This combination of high precision, high resolution and speed enables real-time production-line QC of LEDs and makes the device suitable for R&D purposes as well.

The new system consists of a 550mm-diameter, hemispherical measurement chamber, mated with a CCD-based imaging photometer or colorimeter. The latter is selected from the company's product offering, which include 10-, 12-, 14- and 16bit dynamic range models at several different spatial resolutions. System software supports automated and/or customized measurements as well as data analysis and display functions. Data can be displayed as isometric plots, cross-sectional graphs, radar plots, bit maps and color graphs.