Breast X-rays are dense: therefore, a high level of luminance and perfectly homogeneous lighting are essential for reliable screening. Some micro-calcifications can only be detected with an excellent contrast and no glare. While many manufacturers have focused on the light power, Ella Legros has chosen to concentrate on meeting new expectations expressed by radiologists, giving priority to lighting quality and homogeneity on the entire illuminated area. The French health authorities have issued a quality control protocol for mammography installations (revised in July 1998). It is important to note that this protocol itself refers to the European protocol "European Guidelines for Quality Assurance in Mammography Screening" dated May 1996 and the DIN standard, but is more demanding in terms of homogeneity criteria.