Patents Assigned to Communications Research Lab., Indep. Admin. Inst.
  • Publication number: 20030214645
    Abstract: A method of evaluating free-space optical propagation characteristics includes emitting a plurality of laser beams from a corresponding plurality of laser sources, receiving laser beams at different target points, and measuring the time-based spatial fluctuations between the laser beams thus received. The respective distances from the laser sources to each target point are used to normalize the time-based spatial fluctuations. The difference between the normalized spatial positions of the laser beams at the target points is derived and used to obtain the frequency spectrum of time-based fluctuations of the spatial positions.
    Type: Application
    Filed: May 14, 2003
    Publication date: November 20, 2003
    Applicant: Communications Research Lab. Indep. Admin. Inst.
    Inventors: Moriya Nakamura, Makoto Akiba, Toshiaki Kuri, Naoki Ohtani
  • Publication number: 20030198477
    Abstract: A modulated optical signal processing method and apparatus optically convert an optical signal to an intermediate frequency band that simplifies electrical processing after optical detection, thereby increasing the optical reception sensitivity. Either single-mode light is modulated with a first radio wave overlaid with data, or a modulated optical signal is directly generated, and the optical carrier and optical sideband contained in that modulated optical signal are transmitted, the transmitted optical carrier and optical sideband are input and the input optical carrier and optical sideband are mixed with a radio wave of a predetermined frequency and a combination of an adjacent optical carrier and optical sideband that are closer together than the frequency of the first radiofrequency electrical signal is optically selected from among a frequency-converted or frequency-unconverted optical carrier and optical sideband thus obtained and an electrical signal is detected from this selected optical signal.
    Type: Application
    Filed: January 23, 2003
    Publication date: October 23, 2003
    Applicant: Communications Research Lab. Indep. Admin. Inst.
    Inventors: Toshiaki Kuri, Kenichi Kitayama
  • Publication number: 20020042203
    Abstract: The surface of a substrate having a transmission index is irradiated with a beam of atoms having a slow enough velocity to be adsorbed on the substrate. A laser beam whose frequency is detuned by 1 to 10 gigahertz from the resonant frequency of the atoms is projected onto the substrate at an angle, producing total reflection. The atom beam is reflected at regions at which an intensity of an evanescent wave emitted at this time from the substrate surface is high, and adsorbed at regions where the intensity is low, thereby achieving atomic fabrication patterns on a substrate. By using a hologram image to create the pattern, it is possible to form an atomic fabrication patterns in which the size of features correspond to the diameter of the laser beam, enabling the size to be reduced to the diffraction limit of the laser light.
    Type: Application
    Filed: August 27, 2001
    Publication date: April 11, 2002
    Applicant: Communications Research Lab., Indep. Admin. Inst.
    Inventor: Ryuzo Ohmukai