Abstract: A venetian blind structure using a slat unit having first and second members adjacent one another. The edge portions of the first and second members are hingedly attached to one another. First and second lines are held to the edge portions of the slat unit and are used to tilt the slat when a first and second line are simultaneously pulled in opposite directions.

Abstract: A method of producing stiff polymeric plastic slats incorporates the steps of (a) feeding a reel of planar polymeric plastic film into a roller system which includes at least one pair of rotatable entrance guide rollers; (b) guiding the polymeric plastic film through at least one pair of rotatable line marker rollers; (c) passing the film through at least one pair of truncated rollers to produce a bend in said film of 100 degrees or more; (d) passing the film through a pair of nipping rollers to convert said bend to a fold of between 120 and 180 degrees to thereby produce tension and compression in a ridge region; and, (e) flattening said film out to its final, fixed shape by drawing through a pair of soft, rotatable wheels.

Abstract: A venetian blind utilizing a first elongated slat which is suspended by a pair of lines connected to opposite end portions of the slat along the elongation dimension. A second slat is placed atop first slat and is connected to a third line which moves one end portion of the elongated second slat along the top of the first slat.

Abstract: A driver stage utilizing a zero-crossing detector. The input to the zero-crossing detector consists of a signal which originates from means for generating a pulse width modulated signal. The pulse width modulated signal transformed and rectified before transmission to the zero-crossing detector. A solid state switch is placed across a voltage source and is operated by the output of the zero-crossing detector. The driver may be combined with a similar driver to serve as an inverter.