Abstract: A light emitting control device for a light emitting diode print head includes a control unit, a pulse-mask unit, a strobe unit and a data output unit. The pulse-mask unit outputs n clock signals in sequence to a light emitting diode print head. The strobe unit outputs a strobe signal to the light emitting diode print head, so as to switch on the light emitting diode print head. The data output unit outputs a print data signal to the light emitting diode print head. When the pulse-mask unit outputs a k-th clock signal of the n clock signals, the pulse-mask unit delays the k-th clock signal for a predetermined time, and the data output unit pauses outputting the print data signal. After the predetermined time, the pulse-mask unit and the data output unit continue to output the rest of the clock signals and the print data signal.

Abstract: A light emitting control device for a light emitting diode print head includes a control unit, a pulse-mask unit, a strobe unit and a data output unit. The pulse-mask unit outputs n clock signals in sequence to a light emitting diode print head. The strobe unit outputs a strobe signal to the light emitting diode print head, so as to switch on the light emitting diode print head. The data output unit outputs a print data signal to the light emitting diode print head. When the pulse-mask unit outputs a k-th clock signal of the n clock signals, the pulse-mask unit delays the k-th clock signal for a predetermined time, and the data output unit pauses outputting the print data signal. After the predetermined time, the pulse-mask unit and the data output unit continue to output the rest of the clock signals and the print data signal.

Abstract: A process for producing crystalline silicon nitride powder by a gas phase reaction of ammonia (NH.sub.3) and silane (SiH.sub.4) with a molar ratio of 7:1 or above at a temperature of 900.degree. C. or above and the heating the as-reacted amorphous powders at a temperature of 1350.degree. C. to 1800.degree. C. to convert the powders to a highly pure and submicron crystalline silicon nitride powder comprising at least a 90% .alpha.-Si.sub.3 N.sub.4 phase.