Ntt Docomo, Inc.

Other

Tokyo Institute of Technology

Docomo, Inc.

Fusho Ishii

Yuji Aburakawa

Kazuhiko Takahashi

Fusao Ishii

Toru Otsu

Mikiko Nakanishi

Keiichi Murakami

Koji Maeda

Yasushi Yamao

Shinji Kimura

Masahiro Yamaguchi

Tomoya Nakamura

Shunsuke Igarashi

Koichiro Yamaguchi

Hitoshi Yoshino

Hirohito Suda

Yuji Nakayama

Kazuoki Ichikawa

A compact light source for a projection display is disclosed enabling eye-glass display using a Fresnel mirror reflecting light without a distance as conventional prism type reflector.

Image device with a compact homogenizer

A blur compensation system includes: a mirror on which light of an image from a predetermined position is incident and which reflects light of a specific wavelength such that an incidence angle and an emission angle of the light of the specific wavelength are different from each other; a mirror that is disposed at a position on which the light of an image which is reflected by the mirror is incident and reflects the light of the specific wavelength such that an incidence angle and an emission angle of the light of the specific wavelength are different from each other; and a lens that is disposed on an optical axis of the light of an image between the mirror and the mirror and changes a direction of the light of an image which is reflected by the mirror such that light of a wavelength other than the specific wavelength out of the light of an image which is reflected by the mirror is emitted in the same direction as the light of the specific wavelength from an emission position of the light of the specific wavelength in the mirror.

Blur compensation system

A compact integrator of light beams is disclosed using a diffractive optical element to integrate multiple beams into a single beam regardless of wavelength or polarization.

Light source for projection display

A see-through image display system having a DOE often has undesirable light or so called ghost images due to the quantization of saw tooth shape of DOE surface. This invention provides ways to eliminate ghost images.

Ghost image elimination of doe using fourier optics method

A see-through image display system having an Exit-Pupil-Expander (EPE) to enlarge the eyebox of display is disclosed. The EPE uses a hologram functioning as a micro-lens-array as well as collimation lens.

Optics of wearable display to increase eye-box

A picture presentation systempresents a user U with a picture where a virtual image Di is created in a space in front of the user U. The picture presentation systemincludes a hologram mirrorconfigured to reflect a picture composed of light of a specific wavelength at an angle different from an angle of incidence and transmit light other than the light of the specific wavelength, and a screenconfigured to display the picture toward the hologram mirror. The hologram mirror, being placed opposite to the user U, reflects the picture from the screenin such a way that the user U can visually recognize the virtual image Di of the picture at a position on the opposite side from the user U across the hologram mirror(arrow AR).

Picture presentation system

A see-through image display system with high resolution up to 4K, wide field of view (FOV) beyond 60 degrees and small form factor is proposed. The optics for the display incorporates optical elements including hologram, DOE, lens and mirror with free form surfaces. This display system is suitable for a wearable display.

Optics of wearable display devices

A compact illuminator for a see-through image display system with highly uniform light distribution is disclosed. This invention enables wearable displays such as eye-glass type see-through display. This system provides a wide divergent beam from a display device so that a viewer can have a large eyebox.

Illuminator for a wearable display

A reception side radio station has a notification signal generatorwhich transmits a notification signal for notifying information of a frequency of a radio link being used at the radio station, and a transmitterwhich transmits information indicating a reception power level and its frequency as radio signal data. On the other hand, a transmission side radio station has a notification signal measurerwhich measures a reception power level of the notification signal and detects the frequency notified by the signal, and a frequency band controllerwhich determines an assignable frequency band for a radio link between the transmission side radio station and the reception side radio station based on the radio signal data and the notification signal.

Communication control method and communication control system

A radio communication system comprises: a radio receiver including an interference canceller configured to generate a replica of a received signal and remove an interference signal from the received signal, and a frequency offset estimator configured to estimate a carrier frequency offset between a carrier frequency of the interference signal and a carrier frequency of a desired signal included in the received signal; and a radio transmitter including a frequency controller configured to adjust a carrier frequency of a transmitted desired signal to the carrier frequency of the interference signal based on the carrier frequency offset received from the radio receiver.

Radio communication system, radio station, and radio communication method

An information transmission system for transmitting information from a sending apparatus to a receiving apparatus is provided. The information transmission system includes: a sending apparatus for modulating an information signal, generating a plurality of signals including an optical signal from the information signal which is modulated, and transmitting the plurality of signals via a plurality of routes; and a receiving apparatus for receiving the plurality of signals from the sending apparatus, diversity-combining the plurality of signals, and outputting the information signal, in which the plurality of signals are a plurality of optical signals or signals including a radio signal.

Information transmission system and information transmission method, and, optical space transmission system and optical space transmission method

A central control station, which controls radio base stations connected thereto via radio links and optical fiber links, includes a demultiplexing unit which demultiplexes signals supplied from an upper-level station, signal conversion units which convert the respective demultiplexed signals into converted signals having a unified transmission format, and a distribution unit which distributes the converted signals to the radio links and the optical fiber links.

Radio base station system and central control station with unified transmission format

A radio receiver is provided with a beam-width-variable antenna that receives a radio signal and is capable of changing the beam-width; an interference canceler for removing interference waves from the received radio signal and outputting an interference-wave-removed signal; a measuring device for measuring reception quality of the received signal based on the interference-wave-removed signal; and a beam-width controller for controlling the beam-width of the beam-width-variable antenna based on the reception quality from the measuring device.

Radio receiver and receiving method for controlling the beam-width of an antenna

When a signal is sent from a wireless base station-a wireless modem-converts the signal to a signal of a unified transmission form. The switch-switches the signal to one of wireless transceivers--and the optical transceiver-The wireless transceiver-or-sends the signal to a control stationor a wireless base stationvia a wireless circuitThe optical transceiver-converts the signal into an optical signal and sends the optical signal to a wireless base station-via an optical fiber circuit

Mobile communication system and switching apparatus

A frequency band controlling partdetermines a frequency band assignable to a transmission line according to the frequency, bandwidth, and the power of the interference wave at a base stationby means of a supplied control signal from a separating part. The frequency band controlling partselects a frequency band for the transmission line and a frequency band for the reception line for the base stationaccording to this assignable frequency band contained in the control signal.

Growing community of inventors

Yokohama, Japan

Yuji Aburakawa