What is flicker?
Flicker is a temporal light artifact (TLA) that is caused by visible and invisible changes in the light's output. Unlike incandescent and fluorescent lamps, LED light sources can quickly be turned on without dissipation, which causes varying levels of flicker. The level, frequency and percentage of flicker can have different effects on the health and safety of both people and animals exposed to it. Flicker can be problematic for people with medical conditions like for example migraine headaches, epilepsy and autism. Moving objects may appear stationary, which can create a workplace hazard and interfere with videography equipment for example by creating a visual disruption in filming.
While flicker percentage and flicker index time domain measures have been well known for many years, there are new metrics that add frequency domain components that must also be considered. The Stroboscopic Effect Visibility Measure (SVM), developed by Philips and CIE, identifies potential perception issues related to detecting the motion of objects. The metric is normalized to a value of 1 based on controlled tests on human subjects. 50% of the observers here would notice that objects move much slower than they actually do. A value of less than 1 means that less than 50% of the observers have the problem. A value of more than 1 means that more than 50% of the observers are affected.
Quality and precision
The ILT710 sensor features a CIE photodiode with "human eye response” sitting behind a domed polycarbonate cosine-correcting diffuser to provide the accurate collection of light from all angles. It provides proprietary analog and digital signal processing to enable over-sampling at a rate of 50 kHz with true 12-bit resolution over light levels down to 1 lux, while maintaining the resolution through all LED dimming levels including high PWM frequencies. The meter also provides ILT's NIST-traceable and ISO17025-accredited lux calibration which allows the meter to be used for both light-level compliance auditing and flicker measurement in office spaces, hospitals, schools, sports and entertainment arenas, manufacturing environments, and more.
Characteristics of the ILT710 Flicker / Illuminance Meter
- Sophisticated flicker measurement instrument for use in product development, field testing and measurement and on-site audits
- Outstanding cosine response
- Data transfer and power supply via USB
- Stand-alone operation with integrated battery
- Memory for 1000 measuring points
- Graphic display of light intensity over time
- Evaluation of TLA to various calculation methods like flicker percentage, flicker index and SVM
Do you have further questions? Are you interested in testing the ILT710?