For the past 2000 years of Orthodox Judaism, men and women have worshipped separately, divided either by a solid partition or by using a balcony. Now a professor at Washington University has invented a partition that will allow one-way viewing without the problems associated with conventional see-through mirrors.A combination of two-way mirrors angled at 45° and panels of flat black paint opposite panels of wallpaper create a partition that is see-through from one side only. The partition, called a mehitza, prevents the men from being distracted by the women, in accordance with Orthodox Jewish law. No similar restriction enjoins the women from seeing the men. In fact, many women wish to see the reading of the Torah at each service. A conventional two-way mirror requires that the women's side be much darker than the men's, which makes reading difficult. The mirror creates a reflection that also can be distracting. Mechanical engineering professor Richard L. Axelbaum has designed a mehitza that uses glass angled at 45° to allow the women to see through the partition while showing the men a pattern that looks like wallpaper. "In the past there was just a partition, and some women felt more removed from the service. This allows them to feel more a part of the service," he said. The design came to him as the result of a mistake. Leaving a Boston synagogue after attending a service, Axelbaum thought he noticed two-way glass installed at an angle in the partition. He learned later that the glass was installed vertically. The window also has applications for residential and commercial security because ambient light conditions do not affect its transparency. The window also can be made transparent to both sides.