Abstract: A DC-AC inverter has an adjustment device for adjusting wave shape of output thereof includes a feedback circuit, and a zero-crossing detector; the feedback circuit will detect and measure output voltage of the inverter, and feedback-control the inverter to make the inverter output a demanded stable fixed voltage, thus preventing the output voltage of the inverter from changing owing to an input voltage and the loading effect caused by electric appliances connected thereto; the zero-crossing detector is used to detect and measure the frequency and wave shape of the output of the DC-AC inverter therefore the DC-AC inverter can be further connected in parallel to another DC-AC inverter or an utility grid when the feedback circuit is used to feedback-control the inverter for the inverter to provide a demanded stable fixed voltage output.

Abstract: A DC-AC inverter has an adjustment device for adjusting wave shape of output thereof includes a feedback circuit, and a zero-crossing detector; the feedback circuit will detect and measure output voltage of the inverter, and feedback-control the inverter to make the inverter output a demanded stable fixed voltage, thus preventing the output voltage of the inverter from changing owing to an input voltage and the loading effect caused by electric appliances connected thereto; the zero-crossing detector is used to detect and measure the frequency and wave shape of the output of the DC-AC inverter therefore the DC-AC inverter can be further connected in parallel to another DC-AC inverter or an utility grid when the feedback circuit is used to feedback-control the inverter for the inverter to provide a demanded stable fixed voltage output.

Abstract: An integrated advertisement board includes a frame, several light emitting elements arranged on the frame in a form of a matrix, and a controlling circuit electrically connected to the light emitting element; the controlling circuit is used for making each light emitting element emit light and stop emitting light in an alternate way for the light emitting element to present patterns as well as for the patterns to have constantly changing appearance.

Abstract: An integrated advertisement board includes a frame, several light emitting elements arranged on the frame in a form of a matrix, and a controlling circuit electrically connected to the light emitting element; the controlling circuit is used for making each light emitting element emit light and stop emitting light in an alternate way for the light emitting element to present patterns as well as for the patterns to have constantly changing appearance.

Abstract: LED lamps include a hollow light-transparent ball and one or more LED of the same or different colors fixed behind the ball, which has an inner semi-transparent layer and an outer transparent layer. The semi-transparent layer has a larger deflecting percentage than the outer transparent layer so that light emitted by the LED may deflect and collide with each other many times in the semi-transparent layer of the ball to produce soft and evenly mixed colored light when seen through the ball.

Abstract: A device for finding a position of a human comprises a micro controller, a pyro-electrical infrared sensing unit, a first motor, a rotating speed feed back unit, an ultrasonic sensing unit and a second motor. The infrared sensing unit is fitted to an edge of a disc coupled to the shaft of the first motor. The rotating speed feed back unit has a rotating disc which is also coupled to the shaft of the first motor. The ultrasonic sensing unit is fitted to an edge of a second disc coupled to the shaft of the second motor such that it can move with rotating of the second disc. The micro controller activates the first motor and the infrared sensing unit to search for a human, and figures out the direction of that human by means of the rotating speed feed back unit. At the same time, the controller activates the second motor for the ultrasonic unit to be directed to the found human; thus, the distance from that human to the device is available.

Abstract: A remotely controllable wall switch includes a housing, a push button and a receiver contained in the housing, and a transmitter. The receiver has a circuit board connected to two lead wires of a power source and a load and the push button. A lead wire of the power source and the load are connected to each other. In use, the push button of the receiver or a press key of the transmitter is pressed to control the receiver, to connect power to the load or disconnect it.

Abstract: A color identifying device includes an emitter for supplying light to throw on a tested object, an amorphous photosensor, an amplifier, an ADC and a microprocessor. The emitter is formed with a LED producing three original colors or with three separate LED producing separate colors of red, green and blue. The photosensor receives the reflected light from the object and sends signals of three colors to the amplifier which amplifies the signals and sends them to the ADC. Then the ADC converts the analog signals into digital signals to be sent to the microprocessor which calculates the digital signals by a program identifying the colors of the object accurately.