Abstract: A three-dimensional printer includes a projector, a tank, and a platform. The projector includes a light source, a digital micromirror device, and a controller. The digital micromirror device includes a micromirror, and the micromirror may be switched between an on state and an off state according to a control signal. The controller is electrically connected to the digital micromirror device and the light source. The controller further includes a judgement unit. The judgement unit may output the control signal to switch the micromirror to the off state when the light source is in the off state. The platform is adjacent to the tank. In addition, a manufacturing method for a three-dimensional printer is provided.

Abstract: A three-dimensional printer includes a projector, a tank, and a platform. The projector includes a light source, a digital micromirror device, and a controller. The digital micromirror device includes a micromirror, and the micromirror may be switched between an on state and an off state according to a control signal. The controller is electrically connected to the digital micromirror device and the light source. The controller further includes a judgement unit. The judgement unit may output the control signal to switch the micromirror to the off state when the light source is in the off state. The platform is adjacent to the tank. In addition, a manufacturing method for a three-dimensional printer is provided.

Abstract: An LED lighting device includes a luminescent circuit, a detecting circuit, an adjustable current source and a dimming control circuit. The luminescent circuit is driven by a rectified AC voltage for providing light. The detecting circuit is configured to detect a rising edge or a falling edge of the LED current associated with a frequency of the rectified AC voltage. The dimming current regulator is configured to vary a duty cycle of the LED current according to a PWM signal. The dimming control circuit is configured to generate the PWM signal and synchronize a frequency of the PWM signal with the frequency of the rectified AC voltage at the detected rising edge or the falling edge of the rectified AC voltage.

Abstract: An LED lighting device includes a luminescent circuit, a detecting circuit, an adjustable current source and a dimming control circuit. The luminescent circuit is driven by a rectified AC voltage for providing light. The detecting circuit is configured to detect a rising edge or a falling edge of the LED current associated with a frequency of the rectified AC voltage. The dimming current regulator is configured to vary a duty cycle of the LED current according to a PWM signal. The dimming control circuit is configured to generate the PWM signal and synchronize a frequency of the PWM signal with the frequency of the rectified AC voltage at the detected rising edge or the falling edge of the rectified AC voltage.

Abstract: An LED lighting device includes multiple luminescent devices driven by a rectified AC voltage. The multiple luminescent devices are turned on flexibly in a multi-stage driving scheme using multiple current controllers. The current settings of the two driving stages with the highest current level and the second highest current level are adjusted according to the variation in the rectified AC voltage VAC or according to the variation in the duty cycle of the luminance device due to the variation in the rectified AC voltage. The present invention can improve the line/load regulation of the LED lighting device when the rectified AC voltage somehow fluctuates between its upper bound and lower bound.

Abstract: An LED lighting device includes multiple luminescent devices driven by a rectified AC voltage. The multiple luminescent devices are turned on flexibly in a multi-stage driving scheme using multiple current controllers. The current settings of the two driving stages with the highest current level and the second highest current level are adjusted according to the variation in the rectified AC voltage VAC or according to the variation in the duty cycle of the luminance device due to the variation in the rectified AC voltage. The present invention can improve the line/load regulation of the LED lighting device when the rectified AC voltage somehow fluctuates between its upper bound and lower bound.