Abstract: A manufacturing method of a waveguide and a head mounted display device having the waveguide are provided. The head mounted display device includes a display unit, a first waveguide and a second waveguide. The display unit is configured to provide an image beam. The first waveguide is located between the display unit and the second waveguide. The first waveguide is configured to transmit the image beam to the second waveguide and adjust a light shape of the image beam to maintain a field angle and expand a pupil in a single dimension. The second waveguide is configured to transmit the image beam to outside of the head mounted display device, and the second waveguide can extend a light transmission path and provide a uniform image beam.

Abstract: A load identification system includes an AC-power input unit, a load, a zero-crossing detector, a microcontroller, a first and a second current phase detectors. The zero-crossing detector is configured to output a zero-voltage pulse signal when a zero-crossing signal of the AC-power input unit is detected. The first current phase detector detects a current flowing through the load to output a first voltage signal. When the current flows along a first direction, the first voltage signal is at a high level. The second current phase detector is configured to detect the current flowing through the load to output a second voltage signal. When the current flows along a second direction, the second voltage signal is at a high level. The microcontroller is configured to receive and identify the type of the load according to the zero-voltage pulse signal, the first and the second voltage signals.

Abstract: A laser interferometer system includes a beam splitter to split a laser beam into first and second beam sets, a first retroreflector mounted to an object to reflect the first beam set, a first detecting device for detecting movements of the object in x-, y- and z-axis directions based on the reflected first beam set, a second retroreflector mounted to the object to reflect the second beam set, and a second detecting device for detecting rotations and movements of the object with respect to the y- and z-axis directions based on the reflected second beam set. The movements of the object in the z-axis direction obtained by the first and second detecting devices are used to obtain a rotation of the object with respect to the x-axis direction.

Abstract: A laser interferometer system includes a beam splitter to split a laser beam into first and second beam sets, a first retroreflector mounted to an object to reflect the first beam set, a first detecting device for detecting movements of the object in x-, y- and z-axis directions based on the reflected first beam set, a second retroreflector mounted to the object to reflect the second beam set, and a second detecting device for detecting rotations and movements of the object with respect to the y- and z-axis directions based on the reflected second beam set. The movements of the object in the z-axis direction obtained by the first and second detecting devices are used to obtain a rotation of the object with respect to the x-axis direction.

Abstract: A light emitting diode driving system includes an infrared ray burning device and a light emitting diode driving device. The light emitting diode driving device includes an infrared ray receiving unit, a signal transforming unit, a storage unit, a pulse width modulating unit and a diode driving unit. The infrared ray receiving unit receives a burning signal transmitted by the infrared ray burning device; the signal transforming unit transforms the burning signal into a current control command and transmits it to the storage unit. The signal transforming unit generates a current control signal in accordance with the current control command in the storage unit. The pulse width modulating unit generates a pulse width modulation output current control signal according to the current control signal. The diode driving unit drives the light emitting diode by the pulse width modulation output current control signal.

Abstract: The current adjustment apparatus includes a communication interface, a current generating module, and a current adjustment module. The current generating module includes a microprocessor, a memory for storing a current setting parameter, and a current generating unit; the memory and the current generating unit are electrically connected to the microprocessor. When the current adjustment module is not physically connected to the current generating module, the microprocessor makes the current generating unit generate a driving current in response to the current setting parameter; when the current adjustment module is physically connected to the current generating module via the communication interface, the microprocessor makes the current generating unit generate the driving current in accordance with a setting signal from the current adjustment module, and the microprocessor further overwrites the current setting parameter in accordance with the setting signal when receives a writing signal.

Abstract: A pulse width modulation control unit multiplies a value of a user side setting signal by a value of a dimming signal to obtain a pulse width modulation output current control signal. The pulse width modulation control unit sends the pulse width modulation output current control signal to a light emitting diode driving unit. The light emitting diode driving unit multiplies a value of the pulse width modulation output current control signal by a value of a maximum output current of the light emitting diode driving unit to obtain a light emitting diode pulse width modulation driving current. The light emitting diode driving unit drives a light emitting diode by the light emitting diode pulse width modulation driving current.

Abstract: A pulse width modulation control unit multiplies a value of a user side setting signal by a value of a dimming signal to obtain a pulse width modulation output current control signal. The pulse width modulation control unit sends the pulse width modulation output current control signal to a light emitting diode driving unit. The light emitting diode driving unit multiplies a value of the pulse width modulation output current control signal by a value of a maximum output current of the light emitting diode driving unit to obtain a light emitting diode pulse width modulation driving current. The light emitting diode driving unit drives a light emitting diode by the light emitting diode pulse width modulation driving current.