Abstract: Disclosed is a film adherable to polystyrene on at least one surface thereof.

Abstract: It is aimed to provide a phase modulation apparatus that realizes high-precision phase modulation in high-speed phase modulation of dual optical pulses. A phase modulator 105 included in the phase modulation apparatus, when a dual optical pulse with a time difference composed of a signal optical pulse SP and a reference optical pulse RP passes therethrough, phase-modulates this dual optical pulse in proportion to an applied voltage of an electrical pulse. As a result, a phase-modulated SP? and a phase-modulated RP? are output. A modulation signal generator 106 outputs an electrical pulse of a predetermined bias at an input timing of a trigger signal, according to an input of a four-valued data signal, for example. The modulation signal generator 106 outputs, for one input of the trigger signal, a dual electrical pulse having a time difference and having opposite polarities.

Abstract: It is aimed to provide a phase modulation apparatus that realizes high-precision phase modulation in high-speed phase modulation of dual optical pulses. A phase modulator 105 included in the phase modulation apparatus, when a dual optical pulse with a time difference composed of a signal optical pulse SP and a reference optical pulse RP passes therethrough, phase-modulates this dual optical pulse in proportion to an applied voltage of an electrical pulse. As a result, a phase-modulated SP? and a phase-modulated RP? are output. A modulation signal generator 106 outputs an electrical pulse of a predetermined bias at an input timing of a trigger signal, according to an input of a four-valued data signal, for example. The modulation signal generator 106 outputs, for one input of the trigger signal, a dual electrical pulse having a time difference and having opposite polarities.

Abstract: Provided is a quantum cryptography communication apparatus capable of preventing a go photon pulse from being phase modulated and also capable of freely selecting any repetitive frequency of a light source.

Abstract: A qubit generating unit generates a qubit having a predetermined quantum state. A qubit encoding unit performs quantum encoding of the generated qubit. A first pseudo-random number generating unit generates a first pseudo-random number from secretly shared information, which has been secretly shared with the quantum receiving device in advance. A quantum modulator performs quantum modulation of the qubit on which quantum encoding has been performed based on the first pseudo-random number and sends the modulated qubit to the quantum receiving device. A second pseudo-random number generating unit generates a second pseudo-random number from secretly shared information which has been secretly shared with the above quantum sending device in advance synchronously with generation of the above first pseudo-random number.

Abstract: A wavelength demultiplexer demultiplexes a wavelength multiplexed incident photon pulse string based on wavelengths of the photons in the photon pulse string. Each of a plurality of photon detectors detects a photon that is demultiplexed by the wavelength demultiplexer and outputs a signal based on detected photon, and a bias applying unit applies a gate pulse as a bias voltage to at least some of the photon detectors to match an incidence timing of an output light of the wavelength demultiplexer to the photon detectors. A data processor converts the signals from the photon detectors into time series signals.

Abstract: An objective, when extracting from data such as an image, an audio, and a moving picture, is to extract the information from raw data that has not been processed for extraction, extract many different items of information for different purposes from the same data, and increase the amount of information that can be extracted. In a mobile phone with camera 101, a photographing section 204 photographs an image. A data analyzing section 207 analyses the image based on analysis definition information, which is stored in a definition storing section 201, to define how much data in which part to be read in what order when extracting information from the image. A data converting section 208 extracts information from the image based on code definition information, which is stored in the definition storing section 201, to define a method of computing data taken out according to the analysis definition information.

Abstract: Each of a transmitter (1) and a receiver (2) divides temporarily-shared data into one or more purification blocks and one or more disposable blocks, and mixes each purification block so as to enlarge a Hamming distance between corresponding purification blocks being held by the transmitter (1) and the receiver (2) by using a Hamming distance amplification effect. The transmitter (1) Vernam-encrypts the mixed data with the disposable data and transmits the mixed data to the receiver (2), and the receiver (2) decrypts the received Vernam-encrypted data by using a disposable block owned thereby, and compares the Hamming distance between the purification block owned thereby with the mixed data with a predetermined value so as to judge whether each purification block can be shared between the transmitter (1) and the receiver (2).

Abstract: Provided is a quantum cryptography communication apparatus capable of preventing a go photon pulse from being phase modulated and also capable of freely selecting any repetitive frequency of a light source.

Abstract: A qubit generating unit 40 generates a qubit having a predetermined quantum state. A qubit encoding unit 70 performs quantum encoding of the generated qubit. A first pseudo-random number generating unit 60 generates a first pseudo-random number from secretly shared information 3 which has been secretly shared with the quantum receiving device 200 in advance. A quantum modulator 80 performs quantum modulation of the qubit on which quantum encoding has been performed based on the first pseudo-random number and sends the modulated qubit to the quantum receiving device 200. A second pseudo-random number generating unit 220 generates a second pseudo-random number from secretly shared information 21 which has been secretly shared with the above quantum sending device 100 in advance synchronously with generation of the above first pseudo-random number. A qubit demodulator 230 performs quantum demodulation of the qubit which has been received from the quantum demodulator 80 based on the second pseudo-random number.

Abstract: In case of the high-speed operation, it is difficult to ignore the time required for the voltage to rise to the level of voltage to be applied and the time to fall to 0V when the voltage is applied to the phase modulator. The first phase modulator 71 and the second phase modulator 73 are connected in parallel, and the optical path is switched by the switching unit 55 of the control unit 51 between the first optical switch 33 and the second optical switch 35. The switching unit 55 of the control unit 51 supplies the phase modulation data 31 stored in the phase modulation data memory 53 to the first voltage generating unit 57 or the second voltage generating unit 59 to generate the voltage necessary for the phase modulation.

Abstract: An optical system of a transmission device for quantum cryptograph includes a Faraday mirror and a phase modulator. The phase modulator has multiple refractivity, and it is inevitable to lose an extreme amount of input due to the configuration of the optical path. As a result, the S/N ratio is reduced, which makes an adjustment at start time difficult. A light pulse incident to the transmission device includes two light pulses of the TE polarization wave and the TM polarization wave for a phase modulator 8. The light pulse of the TE polarization wave is changed to the TM polarization wave by a Faraday mirror 7, and the TM polarization wave is changed to the TE polarization wave by rotating the polarization plate and reflecting by the Faraday mirror 7, and output from the transmission device. Two polarization beam splitters 5 and 6 are used so that the light pulse of the TM polarization wave should bypass the phase modulator 8. Only light pulse of the TE polarization wave is carried to the phase modulator 8.

Abstract: In case of the high-speed operation, it is difficult to ignore the time required for the voltage to rise to the level of voltage to be applied and the time to fall to 0V when the voltage is applied to the phase modulator. The first phase modulator 71 and the second phase modulator 73 are connected in parallel, and the optical path is switched by the switching unit 55 of the control unit 51 between the first optical switch 33 and the second optical switch 35. The switching unit 55 of the control unit 51 supplies the phase modulation data 31 stored in the phase modulation data memory 53 to the first voltage generating unit 57 or the second voltage generating unit 59 to generate the voltage necessary for the phase modulation.

Abstract: Each of a transmitter (1) and a receiver (2) divides temporarily-shared data into one or more purification blocks and one or more disposable blocks, and mixes each purification block so as to enlarge a Hamming distance between corresponding purification blocks being held by the transmitter (1) and the receiver (2) by using a Hamming distance amplification effect. The transmitter (1) Vernam-encrypts the mixed data with the disposable data and transmits the mixed data to the receiver (2), and the receiver (2) decrypts the received Vernam-encrypted data by using a disposable block owned thereby, and compares the Hamming distance between the purification block owned thereby with the mixed data with a predetermined value so as to judge whether each purification block can be shared between the transmitter (1) and the receiver (2).