|
DIN 5035 标准的第六部分(part 6), 规定了建筑光学测试的光度学参数。相对于逐点测量的照度计,LMK98-4 图像解析的测试技术可以一次性获得整个测试区域的光度分布,得到成千上万个测试数据。同时,还可以根据相机的位置、方向、张角等,计算得到一些几何相关的参数,如观察者的视角度、立体角等,从而进行眩光(Glare)、光幕亮度(veiling luminance),甚至进行UGR的计算评价。
Measurement of the veiling luminance
The equivalent veiling luminance is defined by the illuminances caused by the glare sources on the eye with a direction-dependent weighting.
Often n = 2 is used, with other evaluation functions being applied occasionally. In principle, the veiling luminance results to:
The illuminance on the eye can be obtained from the measuring data of the LMK by simple computational manipulations using the functions offered by the LMK 2000 software.
Glare evaluation using UGR
The glare evaluation of illumination scenes according to UGR also requires the measurement/evaluation of photometric and geometrical quantities. The measuring parameters (luminance as a function of the direction and solid angles) can be measured by means of the image-resolving LMK camera.
The surrounding luminance Lu can be determined through averaging over the whole data record. The glare sources Li can be defined and recorded via luminance thresholds. The appertaining azimuth and the solid angles of the glare sources result from the geometrical data measured in the luminance image and from the parameters of the measuring system (linear magnification for solid angles) as well as from its position in the room. |
|