RF windows are double-glazed with special tempered safety glass that incorporates two layers of SS mesh as the RF shield. The SS mesh is blackened to avoid reflection and the layers are positioned to minimize moiré patterns. The transparency of the windows is excellent and they afford an unhindered view of the scan room. The standard observation window has a viewing area of 1200 mm X 900 mm. Other sizes are optionally available for observation and daylight windows and virtual skylights.