Abstract: A light screen safety curtain system including multiple light screens cascaded together to cooperatively protect an area or machine against unwanted intrusion. Such a system includes a plurality of independently operating light screens electrically connected to each other and to a control unit. When any one light screen detects an unwanted intrusion through a guarded opening, a stop or warning signal is generated by that light screen and is transmitted to the control unit. A method of configuring a light screen safety system without the need for an external programming device is provided.

Abstract: A shielded housing for a computer or the like including top and bottom housing parts. The top housing part includes a top wall and two side walls. The bottom housing part includes bottom, front and back walls. An inverted V-shaped channel is carried by the side walls adjacent the lower edges for a cooperating fit between the channels and upturned flanges carried by the bottom wall planar surface. The inner surfaces of the housing parts include shielding for reduction of electrostatic noise from the enclosure. The cooperating fit between the channels and bottom wall flanges provide and improved side wall junction to prevent electrostatic noise from leaking along the side wall edges.