Misunderstanding 1: Treat the actual lighting angle as the effective angle

The luminous angle of the wall washer is divided into the effective angle and the actual luminous angle. The angle in which the luminous intensity value is half of the axial intensity value and the luminous axial direction (the normal direction) is the effective angle. Twice the half value angle is the viewing angle (or half power angle), which is the actual light emission angle. In practical applications, angles that exceed half the axial intensity are not included in the effective angle because the light is too weak. Therefore, consumers should pay attention to the actual lighting angle of the product when purchasing the product. When calculating the number of products used in the project, the actual light-emitting angle shall prevail, and the effective light-emitting angle can only be used as a reference value.

Myth 2: The higher the power, the higher the brightness.

The brightness of the LED wall washer is determined by the luminous intensity, which is the luminous intensity pointing to the normal direction, that is to say, the luminous flux emitted by the unit solid angle, the unit is candlelight. Since the luminous intensity of wall washers is generally small, the luminous intensity is usually measured in millicandela (mcd). Generally speaking, the light source will emit luminous flux of different intensities in different directions, and the visible light radiation intensity emitted by a unit solid angle in a specific direction is called light intensity, abbreviated as axial brightness.

Myth 3: Expectations of actual service life are too high.

The manufacturer's expected life of the wall washer reaches 100,000 hours MTBF (mean time between failures, the light source life measurement standard used by traditional lighting manufacturers). However, like all basic light sources, the luminous flux of wall washers decreases over time. Therefore, although a wall washer can shine for a long time, MTBF is not the only factor that determines its lifespan.

The attenuation of LED wall washer lumens is affected by many environmental conditions, such as ambient temperature, humidity and ventilation. Lumen decay is also affected by control, thermal management, current flow levels and many other electrical design factors.