Research on Multi-Source Integrated Photometric, Colorimetric & Electrical Test Based on Lumen Measurement

Introduction

With the rapid advancement of green lighting and solid-state lighting industry, precise performance evaluation on photometric, colorimetric and electrical characteristics of light sources has become essential for product market access and technical upgrade. As the foundation of photometric measurement, lumen measurement is adopted to detect total luminous flux, which acts as the core criterion to evaluate brightness, luminous efficacy and energy efficiency grade. Conventional lumen measurement equipment suffers from insufficient precision, limited test items and poor compatibility for diversified lamps, failing to meet the requirement of synchronous multi-parameter inspection on LED and HID products.

Centered on high-precision CCD spectroradiometer and monolithic integrating sphere, LISUN LPCE-2(LMS-9000) system realizes synchronous lumen measurement, colorimetry, photometry, electrical parameter detection and LM-80 lumen maintenance aging test, covering full test scenarios of mainstream lighting lamps. 

High Precision Spectroradiometer Integrating Sphere System LPCE-2(LMS-9000)

Lumen Measurement and Overall System Configuration

Definition and Significance of Lumen Measurement
Lumen (lm) is the international unit of luminous flux, representing total visible radiant power emitted by light sources towards all spatial directions. By homogenizing spatial light field via integrating sphere and calculating total luminous flux with spectroradiometer, lumen measurement becomes a mandatory test item specified in LM-79, LM-80 and CIE-84 standards for determining luminous level, luminous efficacy and energy efficiency classification.

Composition of LISUN LPCE-2(LMS-9000) System
This system is configured with LMS-9000C high precision CCD spectroradiometer as core component, cooperating with monolithic integrating sphere, digital electrical parameter tester, AC&DC power supply, standard reference lamp and standard equipment cabinet to implement synchronous lumen measurement and multi-parameter acquisition. Monolithic integrating sphere effectively reduces light loss and delivers better test accuracy than spliced sphere structure, supporting wide-range lumen measurement from 0.01 lm to 200000 lm.

Applicable Light Source Types
• Energy saving lamps and fluorescent lamps
• HID lamps including high pressure sodium lamps and high pressure mercury lamps
• Cold cathode fluorescent lamps
• LED lamps, LED modules and plant growth lamps

Comprehensive Parameter Test System Based on Lumen Measurement

Taking lumen measurement as the core testing foundation, the system synchronously outputs colorimetric, photometric and electrical data and supports long-term LM-80 aging test to build a full-scale performance evaluation system.

Colorimetric Parameters
Chromaticity coordinates, correlated color temperature, color ratio, peak wavelength, full width at half maximum, dominant wavelength, color purity, color rendering index, CQS, TM-30-24 (Rf, Rg) and spectral distribution graph.

Photometric Parameters
Luminous flux (core index of lumen measurement), luminous efficacy, radiant power, WPE, EQE, EEI, energy efficiency grade, pupillary flux, pupillary flux efficacy, pupillary factor, PAR and PPF for plant growth lighting.

Electrical Parameters

Voltage, current, input power, power factor, displacement factor DF and harmonic content.

LM-80 LED Lumen Maintenance Test
Variation curves of luminous flux vs time, correlated color temperature vs time, CRI vs time, input power vs time, power factor vs time, current vs time and luminous efficacy vs time.

Core Technical Specifications and Precision of Lumen Measurement

The key technical parameters of LISUN LPCE-2(LMS-9000) are listed in the following table to guarantee high accuracy and stability during lumen measurement and multi-index detection.

Standard Compliance of Lumen Measurement

Lumen measurement and all parameter tests of this system comply with domestic and international lighting testing standards to ensure mutual recognition of inspection results:
• Chinese standards: GB/T 5702-2003, GB/T 24824
• International standards: CIE177, CIE-13.3, CIE-84, ANSI-C78.377, IESNA-LM-63-2, LM-79-19, LM-79-24, LM-80, (EU)2019/2015

System Advantages and Practical Application Value

Firstly, outstanding precision for lumen measurement. Equipped with monolithic integrating sphere, self-absorption correction and auxiliary lamp compensation structure, the system improves test consistency for both low-power and high-power lamps with photometric linearity controlled within ±0.5%, covering full-range inspection from miniature light sources to high-power HID products.

Secondly, integrated multi-parameter testing. One-time fixture mounting completes lumen measurement, colorimetry and electrical measurement simultaneously to reduce repeated clamping and shorten testing cycle, satisfying high-speed inspection requirement for production line and laboratory.

Thirdly, long-term LM-80 aging monitoring. Continuous tracking on luminous flux, CCT, CRI and other parameters over testing duration provides continuous raw data for LED service life prediction and reliability verification.

Fourthly, standardized software and report. The system software supports Chinese & English operating interface with certified USB driver, directly exporting formal reports complying with LM-79 and LM-80 for certification application, factory outgoing inspection and R&D file archiving.

Conclusion

Centered on lumen measurement, LISUN LPCE-2(LMS-9000) high precision spectroradiometer & integrating sphere system establishes an all-index photometric-colorimetric-electrical inspection platform applicable for energy saving lamps, fluorescent lamps, HID lamps, cold cathode fluorescent lamps and LED lamps. The system achieves high accuracy on wavelength, correlated color temperature, CRI and luminous flux measurement and fully meets requirements of mainstream domestic and international specifications.

Featuring high precision, stable performance, diversified functions and convenient operation, this testing system is widely adopted in product development, factory quality inspection and third-party certification laboratories, supplying reliable technical solution for lumen measurement and comprehensive performance assessment of lighting products and promoting quality improvement and standardization development of lighting industry.