Resources | White Papers | Test Equipment | Aug 30, 2017

White Paper: FluxGage - A Photometric Test System for LED Luminaires Based on Solar Panels

We present a novel photometric test system for LED luminaires. The new photometric system called „FluxGage“ uses solar panels to detect and measure light. By placing a diffuser and a black pinhole array over a solar panels we achieve a detection surface which is also an absorber. This enables the system to be the same size as the DUT (Device Under Test), as opposed to an integrating sphere which is at least 3 times larger than the DUT. Simulations and experimental results show that this system can measure total flux with an uncertainty of 4.3%. The demonstrated system is used in 2π geometry. The system measures total flux, color parameters (CCT, CRI, chromaticity, etc.) and flicker.

White Paper: INTRODUCTION (EXCERPT)

The integrating sphere is the standard instrument for measuring flux and color of light sources [1],[2]. The fundamental makings of the integrating sphere are its spherical geometry and the white diffusive coating on its interior. Integrating spheres must be at least 3 times larger than the DUT. Additionally, the effect of the DUT‘s absorption on the measurement (self-absorption) must be calibrated. With LED luminaire sizes ranging from several inches to several feet, the required integrating sphere diameter reaches 6-10 feet (2-3 meters).

The FluxGage system is based on an opposite approach a detection surface which is also an absorber, ideally absorbing every photon emitted by the DUT. With this approach, spherical geometry is not required, the measurement device can be the size of the DUT, and the measurement does not depend on the DUT.

The detection surface should have the following properties:

  •  It detects light, i.e. it transforms light into a measurable electrical signal.

  •  Light detection does not depend on angle.

  •  Very little reflection.

    The detection surface should have the following properties:

  •  A diffuser is used to reduce the angle dependence of the solar panel responsivity.

  •  A dense array of pinholes is placed over the diffuser using black matte paint, thus making most of the surface black. The light incident on the panels is therefore spatially sampled by this dense array.

 

_________________________________________________________


Download the White Paper!

 
Provided by

Efi Rotem, Raphael Cohen, Shimon Elstein, Daniel Sebbag, Ephraim Greenfield


 

_________________________________________________________

 

Supported by LED professional (c) 2017
The global information hub
for lighting technologies.

EDITORIAL

WEBINAR (May 14th): How to Achieve Better Products to the Eye Through Virtual Prototyping?

WEBINAR (May 14th): How to Achieve Better Products to the Eye Through Virtual Prototyping? In the CADFEM webinar on May, 14, 2020 you will learn, how physics-based simulations - virtual prototyping - contribute to develop better lighting products. The live presentation pictures the whole process - from editing the geometric model to the definition of light sources and sensors to the use ... Read more »

EDITORIAL

EuControls Introduces Its Zigbee Compatible Ceiling Mount Multi-Sensor 810-PLT-DZB

EuControls Introduces Its Zigbee Compatible Ceiling Mount Multi-Sensor 810-PLT-DZB EuControls is excited to announce the addition of a compact ceiling mount multi-sensor/controller to its growing wireless lighting controls product portfolio. The S810-PLT-DZB is a unique Zigbee compatible energy management device aimed at new and retrofit indoor lighting projects that require ... Read more »

EDITORIAL

Selecting the UV LED Wavelength for Purification Applications

Selecting the UV LED Wavelength for Purification Applications Patrick Durand is the Worldwide Technical Director at Future Lighting Solutions (FLS) with over 15 years of experience in the solid state lighting industry. Patrick leads the FLS Technical Marketing teams and FLS laboratory teams located in multiple regions around the world with the objective of ... Read more »

EDITORIAL

Nichia Showcases LEDs with 'Light so Good'

Nichia Showcases LEDs with 'Light so Good' At Light + Building 2020 held in Frankfurt, Nichia – the leader in high-performance LED solutions – reveals it will present at least three complementary technologies to improve the delivery of light quality under an over-arching banner of 'Light so Good'. Read more »