ABSTRACT

In lighting simulations, a luminaire is usually modeled using a luminous intensity distribution emitted by a single-point source. This so-called far-field approach is valid as long as the dimensions of the luminaire are much smaller than the distance to the calculation surface. This assumption is generally not met in standard indoor lighting and may lead to significant errors in the prediction of illuminances and discomfort glare. This work describes a practical near-field approach based on splitting the luminaire into N point sources. The errors in relation to the near field (infinite value of N) are evaluated as a function of N. This approach generates a more accurate assessment of the Unified Glare Rating in the case of luminaires with non-uniform emission.

摘要

在照明模拟中，灯具通常使用单点光源发出的光强分布进行建模。只要灯具的尺寸远小于到计算表面的距离，这种所谓的远场方法就有效。这一假设在标准室内照明中通常不满足，并可能导致预测照度和不适眩光时出现重大错误。这项工作描述了一种实用的近场方法，该方法基于将灯具分成N个点源。与近场相关的误差（N 的无限值）被评估为N的函数. 对于具有不均匀发射的灯具，这种方法可以更准确地评估统一眩光等级。