Abstract: A suction brush assembly is provided that includes a suction brush casing having a dust introducing channel for introducing dirt and a suction port for drawing the dirt from the dust introducing channel; a first and a second rotation plates rotatably disposed on a bottom surface of the suction brush casing and rotating in the opposite direction to each other; a rotation power source for providing power for rotating the rotation plates; a power transmission transmitting the rotation power of the rotation power source to the rotation plates; and a dirt guidance member formed on the first and the second rotation plates, for scraping off hairs or feathers from a surface to be cleaned to guide them to the dust introducing channel so that the hairs or the feathers can be easily guided to the suction port.

Abstract: An arrayed waveguide grating (AWG) wavelength division multiplexer (WDM) provided with alignment waveguides, and an apparatus for aligning the arrayed waveguide grating wavelength division multiplexer. The wavelength division multiplexer is provided with alignment waveguides, to be used upon coupling the optical waveguide device to optical fiber blocks, in addition to waveguides required for achievement of desired functions, so that it can achieve a desired alignment irrespective of the achievement of those functions. Accordingly, it is unnecessary to know respective operation characteristics of individual devices, thus easy and rapid alignment and bonding can be achieved. In accordance with the present invention, the operation wavelength of the optical wavelength device can be determined by detecting the wavelength of the light output from each alignment waveguide. Accordingly, it is possible to simply determine whether or not the optical waveguide device operates normally.

Abstract: An optical fiber for an optical amplifier, which contains dysprosium ion (Dy3+) with an improved light amplification efficiency at the 1.31 &mgr;m band. The optical fiber includes a germanium-gallium-sulfide (Ge—Ga—S) glass, an alkali metal halide, and Dy as a rare earth element. In the optical fiber, the interaction of electrons of Dy3+ and phonons in the glass lattice can be minimized, so that the multiphonon relaxation of Dy3+0 from 4F11/2 and 6H9/2 to 6H11/2 is slowed down, and thus the fluorescence lifetime at 1.31 &mgr;m is elongated, further improving the fluorescence efficiency of the optical fiber.

Abstract: Disclosed is an optical wavelength multiplexer/demultiplexer with uniform loss. The optical wavelength multiplexer/demultiplexer includes a first star coupler for dividing optical power of input optical signals received from input optical waveguides, an arrayed waveguide grating for guiding the optical signals outputted from the first star coupler therethrough in such a fashion that the optical signals have different phases, respectively, a second star coupler for coupling or dividing the wavelengths of the optical signals outputted from the arrayed waveguide grating, and outputting the resultant optical signals to output waveguides, respectively, and a waveguide mode controller for controlling the profile of a waveguide mode of the optical signals outputted from the arrayed waveguide grating, thereby allowing the optical signals focused at an output terminal of the second star coupler to have flat amplitude distributions.

Abstract: A bidirectional optical wavelength multiplexer/demultiplexer capable of simultaneously performing light multiplexing and demultiplexing is provided. This optical wavelength multiplexer/demultiplexer includes an optical waveguide array having a plurality of optical waveguides, a planar waveguide region connected to the optical waveguide array, and an arrayed waveguide grating connected to the planar waveguide region. In this device, the optical waveguide array further includes a central waveguide formed at a location on which light transmitted from the arrayed waveguide grating to the planar waveguide region is focused, on the interface between the optical waveguide array and the planar waveguide region, and light multiplexed with a plurality of wavelengths is received or output via the central waveguide.

Abstract: An apparatus for forming a thin film using microwave and a method therefor are provided. The apparatus for forming a thin film on a wafer by densifying predetermined soot on a wafer, when the wafer and the soot form a sample, includes a microwave sintering furnace for sealing the sample and exposing the sample to microwave, thus sintering the sample, a sintering furnace atmosphere maker for controlling the state, being the atmosphere of air inside the microwave sintering furnace, a temperature sensor/controller for sensing a temperature inside the microwave sintering furnace, comparing the temperature with a predetermined reference temperature, and outputting an error temperature, and a microwave power source for generating microwave of a predetermined temperature with reference to the error temperature output from the temperature sensor/controller and applying the microwave to the microwave sintering furnace.

Abstract: An optical fiber used for an optical amplifier, is formed by doping glass with rare-earth ions. Both praseodymium ions (Pr+3) and erbium ions (Er+3) are used as the rare-earth ions, and the glass is a fluoride glass or a sulfide glass. The optical fiber can be used at wavelengths of both 1.3 &mgr;m and 1.55 &mgr;m. The light amplification efficiency of an optical amplifier made of the optical fiber can be improved compared to that of an optical amplifier formed of only Pr+3 or only Er+3.

Abstract: A 1×N optical wavelength-division demultiplexer alignment apparatus including a 1×N optical wavelength-division demultiplexer including an input waveguide, N output waveguides and a plurality of alignment waveguides positioned around the input and output waveguides, for demultiplexing signal light and supplying the demultiplexed signal light to the N output waveguides if the signal light has a wavelength in a communication wavelength region, and for supplying the signal light to the alignment waveguides if the signal light has wavelengths outside the communication wavelength region. A single optical fiber block has a single optical fiber to transmit the signal light to the 1×N optical wavelength-division demultiplexer, a multiple optical fiber block having N optical fibers connected to output sides of the N waveguides and alignment optical fibers connected to output sides of the alignment waveguides.

Abstract: An optical fiber for use in a light amplifier. The optical fiber is formed by doping a gerrnanium-gallium-sulfur (Ge—Ga—S) glass containing less sulfur than a GeS2—Ga2S3 stoichiometric composition line with a rare earth element, and further contains 0.1˜10 atomic % of a halogen element base on the Ge—Ga—S glass. By using optical fiber, clustering of praseodymium (Pr+3) ions can be suppressed even when the concentration of added Pr+3 is high, thereby improving light amplification efficiency.

Abstract: An optical wavelength multiplexer/demultiplexer, capable of exhibiting flat spectral response characteristics while minimizing insertion loss, is proposed. The optical wavelength multiplexer/demultiplexer, used in WDM systems, includes a first slab waveguide for dividing powers of input optical signals coupled from the input optical waveguides, an arrayed waveguide grating for guiding the optical signals from the first slab waveguide therethrough in such a fashion that the optical signals have constant phase difference in neighboring waveguides, a second slab waveguide in which the optical signals from the arrayed waveguide grating converge into the focal positions according to their wavelengths, and a taper waveguide interposed between the second slab waveguide and output waveguides and adapted to obtain a flat spectral response while minimizing an insertion loss.

Abstract: An apparatus for aligning an optical waveguide device has functional waveguides for transmitting signal light and internal and external waveguides, located on the periphery of the functional waveguides, with optical fiber blocks and includes an optical source, a first optical fiber block having a plurality of first functional optical fibers each connected to one end of each of the functional waveguides, and a plurality of first alignment optical fibers each aligned with one end of each of the internal and external waveguides for transmitting light generated by the optical source, a second optical fiber block having a plurality of second functional optical fibers each connected to the other end of each of the functional waveguides, and a plurality of second alignment optical fibers each aligned with the other end of each of the internal and external waveguides, a measuring unit for measuring an intensity of light output from the second alignment optical fibers, and a controller for receiving the intensity of l

Abstract: An optical fiber passive alignment apparatus for passively aligning an optical fiber with an input/output optical waveguide of an integrated optical device, and a method therefor. The optical fiber passive alignment apparatus includes: an optical waveguide formed on a planar substrate along the longitudinal direction of the planar substrate, having a core which is shorter than the planar substrate; an optical fiber mounting portion formed to a predetermined length on the planar substrate in the longitudinal direction of the planar substrate, such that the optical waveguide and the optical fiber contact each other, for receiving the optical fiber; and a cavity located between the optical fiber mounting portion and a core of the optical waveguide, filled with a material whose refractive index slightly increases on irradiation by UV rays such that the refractive index of the material is not substantially different from the refractive index of a core of the optical fiber.

Abstract: A Ge--Ga--S-based glass composition having light amplifying characteristics and an apparatus for optical communications using the glass composition are provided. The present invention includes a sulfur-poor Ge--Ga--S based host glass which includes less S than compositions on the composition line of GeS.sub.2 --G.sub.2 S.sub.3 on the ternary phase diagram of Ge--Ga--S, and a rare earth active material doped on the host glass for luminescence and light amplification. Ga of no more than about 10 mol % is included in the host glass. Also, Pr.sup.3+ ions are used as the rare earth active material. Furthermore, for stable vitrification and a blue shift of a short wavelength absorption band, a vitrification stabilizer such as Br and I is added to the host glass.

Abstract: A Ge--Ga--S-based glass composition for performing an optical amplification and an apparatus for optical communications using the same are provided. In the glass composition according to the present invention, an active material for performing luminescence and optical amplification operations is added to the Ge--Ga--S host glass and a transition metal ion moving the distribution of optical amplification gains is added in a range from 0.01 mole % to 0.2 mol %.