Patents by Inventor Nakajima Hisao

Nakajima Hisao has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method and device for the optical filtering and photodetection of intensity-modulated optical signals
    Patent number: 5099350
    Abstract: Method and device for the optical filtering and photodetection of intensity-modulated optical signals.Signals are injected into at least one resonating type semiconductor laser amplifier (2) close to the active layer (14) of this amplifier, the latter being polarized below its threshold current and having at least one resonance wavelength adjusted so as to coincide with the wavelength of at least one of the optical signals in order for this optical signal to be amplified by the amplifier, and the voltage existing between the terminals of the amplifier is detected so as to obtain, in the form of an electric signal, the information carried by the amplified optical signal when the angle between the polarization direction of the latter and the direction of the active layer is small.Application for the embodiment of optical receivers.
    Type: Grant
    Filed: August 1, 1989
    Date of Patent: March 24, 1992
    Assignee: Etat Francais represente par le Ministere des Postes, des Telecommunications et de l'Espace (Centre National d'Etudes des Telecommunications)
    Inventor: Nakajima Hisao