flimmerdrift

Flimmerdrift is a term used in some Nordic-language sources to describe a drift or variation in flicker characteristics of a light source over time. It denotes changes in flicker amplitude or frequency caused by fluctuating electrical conditions, temperature effects, or aging components. The term is not widely standardized outside its regional usage and is less common in English-language literature.

Causes of flimmerdrift include modulation methods used in modern lighting such as pulse width modulation and switching power supplies, which can interact with mains supply, thermal changes, and aging electronics. Temperature fluctuations can alter driver performance, capacitor characteristics, and LED efficiency, all contributing to changes in flicker behavior. Other factors include supply voltage variations, harmonics in the power grid, and the design of dimming control circuits. In some cases, mechanical or environmental factors such as ventilation and enclosure temperature can also influence drift.

Measurement and perception of flimmerdrift rely on analyzing flicker frequency and modulation depth with fast photodetectors and time-domain or frequency-domain methods. Human perception of flicker depends on the frequency and depth of modulation; some individuals may experience discomfort, eyestrain, or headaches when flicker is noticeable even at high frequencies or variable amplitudes. Standards and testing procedures for flicker exist in various regions, but the terminology and emphasis on flimmerdrift vary by jurisdiction.

Mitigation strategies aim to reduce drift and stabilize flicker, including using high-quality constant-current LED drivers, minimizing low-frequency modulation components, improving thermal management, and selecting components with low aging drift. Higher switching frequencies, better filtering, and comprehensive flicker testing during design help ensure consistent light output and reduce perceptible flicker over time.

Related concepts include flicker, flicker fusion threshold, and 1/f noise in electronic systems.