A method and apparatus for controlling the wavelength of a laser. Initially, the wavelength of the laser is coarsely tuned to within a predetermined window around a specified wavelength. After coarse adjustment, a wavelength control loop is activated to finely tune and lock the laser wavelength. In an embodiment, the control loop dithers the wavelength of the optical carrier signal from the laser. The optical carrier signal is then modulated (i.e., with data) in the normal manner. A portion of the modulated optical signal is filtered and detected. The amplitude and phase of the detected signal, which comprises the error signal, is processed and averaged. The averaged signal is then summed with a dither signal to provide a composite signal. A control signal corresponding to the composite signal is then generated and used to adjust the laser wavelength.

Method and apparatus for controlling the wavelength of a laser

A high frequency electrical signal control device comprises a transmitter for generating a high frequency electrical signal, a receiver, a transmission line for propagating the electrical signal, and a structure for radiating the electrical signal propagated through the transmission line to the space or receiving a signal from the space. The degree of coupling of the electrical signal between the space and the transmission line provided by the structure can be variably controlled.

High frequency electrical signal control device and sensing system

To calculate information on a relative distance or positional relationship between an interface section and an object by detecting an electromagnetic wave transmitted through the interface section, and using the electromagnetic wave from the object to detect a relative position of the object with respective to the interface section. Information on the relative spatial position of an object 101 with respect to an interface section 102 that has an arbitrary shape and deals with transmission of information or signal from one side to the other side of the interface section 102 is detected with a spatial position detection method. An electromagnetic wave 106 radiated from the object 101 and transmitted through the interface section 102 is detected by an electromagnetic wave detection section 103, and based on the detection result, information on spatial position coordinates of the object 101 is calculated by a position calculation section 104.

Spatial position detection method, information input method, spatial position detection apparatus, and information input apparatus

Mobile 3D graphical communication is provided in a communication network for wireless devices. A sender can create and customize a 3D graphical representation that will convey the sender's content, and then provide the animation for the 3D graphical representation locally on a sender device or have a remote server provide the animation. The server provides the animated 3D graphical representation to a recipient device so that the recipient device can render the animated 3D graphical for presentation of the sender's content. Transformation (including transcoding) techniques can be used, by the user devices and/or the server, to change the message (from text to audio, from 3D to 2D, etc., for example) to be consistent with animated 3D graphical presentation capabilities of the user devices and/or to match user preferences. Transformation can be performed prior to or during delivery of the content. The 3D graphical communication can also be used to provide content from a content provider to any user device whether wireless or hardwire, such as with a subscription service, or can be used to post animated 3D graphical content at a network location, such as a blog.

System and method for mobile 3d graphical messaging

An apparatus for detecting information on an object includes an irradiating unit, a detecting unit, and an information-obtaining unit. The irradiating unit irradiates the object with electromagnetic waves as a rectangular shaped beam. The electromagnetic waves include a frequency component in (or range of) at least part of a frequency region of 30 GHz to 30 THz, and have variations in magnitude at intervals of 10 −11 seconds or more or a temporally constant magnitude. The detecting unit detects the electromagnetic waves transmitted or reflected by the object through interaction therebetween. The information-obtaining unit obtains information on the object from information on the electromagnetic waves detected by the detecting unit.

Apparatus for detecting information on object

In a light source apparatus, the polarization mode of oscillation light from a semiconductor laser is switchable between two different polarization modes when a modulation current is injected into a portion of a light waveguide of the semiconductor laser. Light in one polarization mode and light in the other polarization mode are separately obtained from the oscillation light from the semiconductor laser. At least the light in one of the two different polarization modes is converted to an electric signal. Current injected into the semiconductor laser is controlled based on the electric signal such that a modulation state of light from the semiconductor laser is stabilized. The light in the other polarization mode, or light in one polarization mode emitted from the other emission side of the semiconductor laser may be used for optical transmission.

Apparatus and method for driving oscillation polarisation selective light source, and optical communication system using the same

PROBLEM TO BE SOLVED: To accurately and efficiently form a film by imparting the material of the film to a plurality of positions, on the basis of the position information calculated with respect to each of the positions. SOLUTION: An image inputted from a CCD camera 7 is image processed in an image processing device 14 to detect the optimum center-of-gravity position for application of a droplet 9 for each element. The resulting information (center-of-gravity position) is combined with the positional information obtained from a position detecting mechanism 16 for detecting the position of a stage 15 having an XY-direction scanning mechanism, whereby the information for the center-of-gravity position on the device of individual elements on an electron source substrate 81 arranged on the stage 15 is determined, and this information is transmitted to a control computer 19. The control computer 19 controls the drive of an ink jet head 8 via an ink jet control and drive mechanism 18. According to this, the droplet 9 is discharged from the ink jet head 8 at arbitrary timing. The position of the ink jet head 8 can be precisely moved by a position correcting control mechanism 17.

Forming method of film, manufacture of electron emission element using the same, and manufacture of image forming device using the film

PURPOSE:To obtain a direct polarization and modulation light-source control system or apparatus in which a dynamic wavelength change is small and in which a modulation state can be kept well, to obtain an integrated semiconductor device, to obtain its driving method and to obtain an optical communication system using it. CONSTITUTION:A semiconductor laser 1-1 is used as a light source for optical communication. The semiconductor laser 1-1 has a structure in which a current flowing to a part of an optical waveguide is modulated and in which two oscillation and polarization modes having different planes of polarization are switched. The semiconductor laser is provided with a means 102 by which two orthogonal polarized waves of output light from the semiconductor laser 1-1 are separated and with means 1-3-1, 1-3-2 which individually receive two separated orthogonal polarized waves. By using signals from the respective receiving means 1-3-1, 1-3-2, an injection current to the semiconductor laser 1-1 is feedback-controlled.

Direct polarization and modulation light-source control system, its apparatus, integrated semiconductor device, its driving method and optical communication method using it

PURPOSE:To obtain an optical semiconductor device with which an optical communication light source, wherein direct polarization modulation system of small dynamic wavelength modulation is used, the drive method for optical communication light source, an optical communication method using thereof, and an optical communication system. CONSTITUTION:A semiconductor laser 1 is used as a communication light source. The semiconductor laser 1 is a structure in which two oscillation polarization modes, having different plane of polarization, are switched by modulating the current to be made to flow through a part of an optical waveguide. A means 2, with which two polarization modes having different plane of polarization of polarized output light of the semiconductor laser 1, a means with which one light of two polarization modes is coupled to an optical transmission path, and a photodiode 3, with which the remaining light is converted to an electric signal, are provided. The current to be made to flow to the semiconductor laser 1 based on an electric signal, is controlled in such a manner that the state of modulation of the light coupled to the optical transmission path 9 is stabilized.

Mishima Seiji

Papers

Apparatus and method for driving oscillation polarisation selective light source, and optical communication system using the same

Forming method of film, manufacture of electron emission element using the same, and manufacture of image forming device using the film

Direct polarization and modulation light-source control system, its apparatus, integrated semiconductor device, its driving method and optical communication method using it

Optical semiconductor device, method of driving communication light source, and optical communication system using thereof

Vorrichtung und Verfahren zur Steuerung einer polarisationsselektiver Lichtquelle, und optisches Kommunikationssystem unter Verwendung desselben