摘要:
A high speed passband phase modulation apparatus and method are provided. In the phase modulation apparatus, an RF phase shifter modulates a phase of a local signal that is generated in a VCO according to a digital input. The RF phase shifter is controlled by a phase-controlled loop so that a baseband phase shifter is phased locked to a modulation reference signal from the local signal and a reference clock signal according to the digital input. The phase-controlled loop phase-locks using the modulation reference signal so that the phase-modulated signal generated in the RF phase shifter has a phase value according to the digital input.
摘要:
A bi-directional optical transceiver includes: an optical fiber for transmitting and receiving first and second optical signals; a transmitter module for generating the first optical signal; a receiver module for detecting the second optical signal; a tap filter for splitting a portion of the first optical signal; a monitor module for monitoring the magnitude of the portion of the first optical signal split by the tap filter; and a wavelength selection filter, which is located between the tap filter and the optical fiber, inputs the first optical signal output from the tap filter into the optical fiber, and inputs the second optical signal output from the optical fiber into an optical detector.
摘要:
A multi-loop transformer includes a first loop built with at least one metal plate forming a magnetic field with electric power supplied; a second loop, disposed in a concentric manner with the first loop, which generates induction current; at least one first sub-loop disposed in the concentric manner with the first loop, and electrically connected to the first loop, the second loop being disposed between the first sub-loop and the first loop; and electric power supply units, disposed between the respective metal plates of the first loop, which supplies electric power to each metal plate. Accordingly, the present invention can improve the efficiency of a power amplifier by reducing the loss of the distributive active transformer (DAT).
摘要:
In the method, a conductive pad of the board is etched to a depth that is greater than 50% and less than 100% of a thickness of the conductive pad. Subsequently, a solder ball may be formed on the etched conductive pad. For example, the conductive pad may be copper.
摘要:
A broadband light source is disclosed. The broadband light source includes a semiconductor optical amplifier for generating and amplifying light of a broadband wavelength, the amplifier having a first end and a second end and a mirror spaced from the second end of the semiconductor optical amplifier to reflect the light, which is provided by the semiconductor optical amplifier, back to the semiconductor optical amplifier, wherein the semiconductor optical amplifier amplifies the light reflected from the mirror and outputs the amplified light to the first end of the semiconductor optical amplifier. The light source further including at least one lens system to converge light passing through the amplifier ends.
摘要:
A reflective semiconductor optical amplifier light source is disclosed. The reflective semiconductor optical amplifier light source includes a transmissive type semiconductor optical amplifier for creating and amplifying spontaneous emission light, a reflector for reflecting amplified spontaneous emission light outputted from the semiconductor optical amplifier such that amplified spontaneous emission light is reflected back into the semiconductor optical amplifier, and a bandpass filter having a predetermined wavelength band width for limiting wavelength bands of the amplified spontaneous emission light capable of passing through the bandpass filter. In one aspect of the invention, the bandpass filter is interposed between the semiconductor optical amplifier and the reflector. In another aspect, a polarization filter is imposed to limit the reflected emission light to a predetermined polarization.
摘要:
An apparatus and method for measuring a three-dimensional shape of an object using a projection moiré device. The method comprises the steps of obtaining a grid pattern image projected on a reference plane of a moving table and applying a buckets algorithm thereto, thereby achieving a reference phase, obtaining a grid pattern image projected on the object set on the moving table and applying a buckets algorithm thereto, thereby achieving an object phase, calculating a difference phase between the object phase and the reference phase, thereby achieving a moiré phase, and unwrapping the moiré phase, thereby achieving a level information of the object. The apparatus and method measure the three-dimensional shape using a projection grid without a reference grid, thereby achieving compactness of equipment, simplicity in usage and manufacturing cost reduction.
摘要:
An ornithopter with an airframe structure that is lightweight, simple and stable and can generate sufficient lift and thrust. The ornithopter comprises a body, a main wing attached to an upper portion of a front section of the body, and a tail wing attached to a rear section of the body. The ornithopter further comprises a power source and a power transmission mechanism installed within a housing of the body. The main wing includes a wing frame composed of a plurality of frame rods and a skin attached to the wing frame for forming an outline of the main wing. The wing frame of the main wing is supported by a support means exposed to the outside at the upper portion of the front section of the body. The power transmission mechanism includes a gear train for adjusting the rotational motion of the power source at a proper speed and transferring it to the main wing, and connecting rods for converting the rotational motion into a swing motion of the main wing. Flight time of the ornithopter can be prolonged considering its weight and the power source can be easily manipulated.
摘要:
A power-driven ornithopter piloted by a remote controller wherein a takeoff and landing motion, a climbing and descending motion, and a turning motion of the ornithopter can be controlled using the remote controller. The ornithopter comprises a body, a main wing attached to an upper portion of a front section of the body, and tail wings attached to a rear section of the body. An electric motor, a power transmission mechanism, a battery, first and second servo motors and a controller are installed within a housing of the body. A crank arm is connected to a rotating shaft of the first servo motor and a connecting rod attached to a free end of the crank arm is then pivotally connected to a lower edge of the horizontal tail support. The second servo motor is mounted into a recess formed at an upper side of a rectangular parallelepiped of the horizontal tail support and a rotating shaft of the second servo motor is disposed on a central axis of the horizontal tail. A vertical tail support is supported by the rotating shaft of the second servo motor so that it can be swung on the rotating shaft of the second servo motor in a right and left direction as the rotating shaft of the second servo motor rotates.
摘要:
A method and a recording medium for measuring three-dimensional thickness profile and refractive index of transparent dielectric thin-film with some patterns or not, which is fabricated in the semiconductor and related industrial field, using white-light scanning interferometry is provided. A method for measuring a thickness profile using white-light scanning interferometry in optical system includes the following steps. A first step is to extracting a phase graph by acquiring an interference signal and performing Fourier transform. A second step is to extracting a mathematical phase graph through modeling of a measurement object. And a third step is to measuring a profile value and a thickness value by applying an optimization technique to an error function determined by using phase values which is acquired from said first step and said second step.