Abstract: The invention relates to a lighting system of alternate current light-emitting diodes (AC-LEDs). The system includes a first, a second and a third AC-LED modules, each two of them being electrically connected in parallel to one another and further electrically connected to a first, a second or a third phase voltage input terminal. The respective AC-LED modules include a first and a second LED modules. The system is further provided with rectifier circuits and multi-stage driver modules. The invention involves driving the AC-LED modules to emit light in an alternate manner using a three-phase AC power source, thereby reducing the flicker index, and further driving the first and the second LED modules to light up in different alternating orders, thereby rendering the light emission of the AC-LED lighting system substantially constant in terms of power and brightness.

Abstract: The present invention involves use of at least two unidirectional elements to provide flow paths for the positive half cycle and the negative half cycle of the AC power input, respectively, and the at least two LED modules are integrated in the flow path of the positive half cycle and the negative half cycle, respectively, and a multi-stage driver module is integrated, so that when the positive half cycle or the negative half cycle is conducting, the at least two LED modules are lit up in different alternating orders, thereby rendering the light emission of the at least two LED modules substantially identical in an AC power cycle in terms of power and brightness. The invention overcomes the problem of uneven brightness of the LED lighting apparatus using a conventional multi-stage driver device.

Abstract: Method of removing hair provides for applying radio frequency radiation to a selected skin zone in conjunction with applying ultrasound waves to the skin zone, with pulling the slackened hair out. A combination of a radio frequency generator, and an oscillator that are connected to tweezers constitute a hair removal device implementing the method. A radio frequency power selector enables selecting a suitable mode of operation depending on the texture of skin and its sensitivity.

Abstract: A latch having a multiple function prevailing-torque mechanism which facilitates engagement and disengagement of the drawbolt and the strike of the latch and provides a simplified construction enabling ease of assembly and adjustment, with the prevailing-torque mechanism serving to retain the component parts in assembled arrangement and in appropriate adjustment. A further latch arrangement includes a positive lock which serves to retain the actuating lever of the latch in a stowed or latched location.