Abstract: Injected into an internal combustion engine are fed pulses via a gate which starts to transmit when the crank shank of the engine is in a particular angular position and stops the transmission when the number of pulses applied to the injectors is equal to a number determined as a function of various operating parameters of the engine. The injectors remain open while pulses are being applied and close when the gate closes.

Abstract: Certain intervals are determined in which output signals from an exhaust gas sensing device are sensed, and then applied to a control circuit, to control the fuel supply system (carburetor, or fuel injection system) in such a direction that a predetermined ratio of fuel and air is being supplied to the engine to provide exhaust gases of predetermined composition. The intervals are determined by a logic circuit which has applied thereto engine operating parameters such as operating time of the engine after having been started, engine speed, engine power condition (idling, or supplying power), engine temperature, or the like.

Abstract: Injectors in an internal combustion engine are fed pulses via a gate which starts to transmit when the crank shaft of the engine is in a particular angular position and stops the transmission when the number of pulses applied to the injectors is equal to a number determined as a function of various operating parameters of the engine. The injectors remain open while pulses are being applied and close when the gate closes.

Abstract: A polarizer structure for a headlight includes an interference-type polarizer followed by an absorption-type polarizer. The interference-type polarizer in one form of the invention is constituted by rectangular plate polarizing sections in a zigzag arrangement, so that the apex angle formed by adjacent polarizing sections is always 90.degree. while the angle of each polarizing section to the optic axis is 45.degree.. In another form of the invention, the polarizer sections are arranged in a diverging louvre arrangement provided with reflecting layers between the polarizing sections, both the polarizing sections and the reflecting layers at an angle of 45.degree. with the optic axis.