摘要:
There is described an information processing apparatus, which makes it possible to prevent a third party from stealing and using data owned by the correctly access-authorized person, so as to securely control the data concerned. The information processing apparatus includes: a data storage section to store data; an acquiring section to acquire positional information of an access-authorized person and a control section to determine whether or not an accessing operation for accessing to the data stored in the data storage section should be allowed, based on a determined result thereof. When the external terminal device tries to access into the data stored in the data storage section or the storing area of the data, the control section transmits a request of inputting authentication information to the external terminal device, in order to determine whether or not the accessing operation to be conducted by the external terminal device should be allowed.
摘要:
A clip which is easily removed from an object to be fixed is provided. The clip includes: two parts including a first member 1 and a second member 2, the first member having a head portion 4 and a shaft portion 5, and the second member having a flange portion 11 and a leg portion 12, wherein an opening 13 is formed in the flange portion of the second member, and the leg portion of the second member is split into two split leg portions 16 to form a gap 17, which communicates with the opening and into which the shaft portion of the first member is inserted between the split leg portions 16, and wherein elastic blades 18 projecting radially are provided in multiple stages along a vertical direction on outer peripheral surfaces of the split leg portions. Consequently, if the shaft portion of the first member is pulled out from the gap between the split leg portions of the second member, the shaft portion of the first member ceases to be present in the gap formed between the split leg portions of the second member. Therefore, if the first member together with the second member is subsequently removed from the object to be fixed while the head portion of the first member is being gripped, the split leg portions are greatly deflected inwardly by making use of the gap, so that it becomes possible to easily remove the clip itself.
摘要:
A method of simultaneously specifying the wavelength dispersion and nonlinear coefficient of an optical fiber. Pulsed probe light and pulsed pump light are first caused to enter an optical fiber to be measured. Then, the power oscillation of the back-scattered light of the probe light or idler light generated within the optical fiber is measured. Next, the instantaneous frequency of the measured power oscillation is obtained, and the dependency of the instantaneous frequency relative to the power oscillation of the pump light in a longitudinal direction of the optical fiber is obtained. Thereafter, a rate of change in the longitudinal direction between phase-mismatching conditions and nonlinear coefficient of the optical fiber is obtained from the dependency of the instantaneous frequency. And based on the rate of change, the longitudinal wavelength-dispersion distribution and longitudinal nonlinear-coefficient distribution of the optical fiber are simultaneously specified.
摘要:
A tilt control apparatus includes an orthogonal shift detector (9) which detects an orthogonal shift by comparing a pair of a plurality of tap coefficients (C1, . . . , C7) of a FIR filter and generates an orthogonal shift signal, and an actuator varies the inclination of the optical axis of the light beam to correct the orthogonal shift, and a tilt controller (10) controls the drive of the actuator in accordance with the orhogonal shift signal to minimize the orthogonal shift. In the information recording operation, the orthogonal shift obtained based on a recording track is previously stored in a temporary storage portion and the stored orthogonal shift is used to conduct the tilt control.
摘要:
An optical waveguide circuit capable of controlling polarization crosstalk is provided. An under cladding is formed on a silicon substrate (11). A core is formed on the under cladding and has a waveguide structure in which one or more optical input waveguides (12) arranged side by side are connected at their exit ends with a first slab guide (13), which is connected at its exit end with an arrayed waveguide (14) composed of plural channel waveguides (14a) that are different in length with the difference preset, and the arrayed waveguide (14) is connected at its exit end with a second slab waveguide (15), which is connected at its exit end with a plurality of optical output waveguides (16). The top of the core is covered with an over cladding to form an optical waveguide portion (10) composed of the under and over claddings and the core. A plurality of light beams having different wavelengths are entered to the core in the multiplexed manner, and the entered light beams are outputted separately on the basis of the wavelength. The claddings and the core are formed from silica glass. The birefringence B in the optical waveguide portion (10) is set so as to satisfy |B|≧1.2×10−4 to reduce polarization crosstalk to −20 dB or less.
摘要:
An arrayed waveguide grating comprise at least two half-wavelength plates 8a1 and 8a2 crossing the center in the length direction of the plurality of arrayed waveguides 4 disposed in series in the vertical direction of the arrayed waveguides 4. By these half-wavelength plates 8a1 and 8a2, a polarization mode conversion part to convert the TE mode and TM mode of signal beams to be transmitted through the arrayed waveguides 4 is formed. The arrayed waveguides 4 are divided into a group of arrayed waveguides 4 crossed by the half-wavelength plate 8a1 and a group of arrayed waveguides 4 crossed by the half-wavelength plate 8a2.
摘要:
In carrying out PWM-recording on optical disks, RESYNC BYTES including a bit compensation part, RESYNC detection part, and bit synchronization part are periodically inserted in the recorded data code stream. After encoding and at the time of decoding, RESYNC BYTES are detected by detection of the RESYNC detection part. The decoder is initialized by detecting the position of the bit synchronization part and decoding is performed satisfactorily free from error. With this configuration, even for synchronization bytes having a comparatively long portion of consecutive code values, bit resynchronization is enabled free from mis-detection caused by peak shift. Even with the recording and reproducing characteristics with an un-symmetrical unerased area of the mark and space parts, the RESYNC detection part is fixed to either mark or space and RESYNC BYTES with little influence on an unerased area can be realized.
摘要:
An arrayed waveguide grating type optical multiplexer/demultiplexer including an arrayed waveguide grating having a plurality of channel waveguides. Concave end faces of input-side and output-side slab waveguides are connected to opposite ends of the diffraction grating. At least one input waveguide and at least one output waveguide are connected to the other concave end faces of the input-side and output-side slab waveguides, respectively. The focal length of the output-side slab waveguide end face is longer than the focal length of the input-side slab waveguide end face. The optical multiplexer/demultiplexer has a sufficiently flat wavelength-dependent spectrum response in passing channel spacings, and helps construct an optical wavelength multiple communication system having a good signal-to-noise ratio.
摘要:
An arrayed waveguide grating type optical multiplexer/demultiplexer includes input waveguides, an input-side slab waveguide, an arrayed waveguide diffraction grating, an output-side slab waveguide, and output waveguides. A junction between each input waveguide and the input-side slab waveguide is tapered such that the end portion of the input waveguide gradually widens in the width direction of the path toward the input-side slab waveguide, and includes two separate small-width waveguide portions arranged separately from the end portion of the input waveguide and extending in a line with taper of the tapered end portion, and a single large-width waveguide portion arranged separately from the small-width waveguide portions.
摘要:
An electronic apparatus wherein a light receiving window is formed in a cabinet for passing therethrough an input command signal supplied from a remote commander to execute various control actions, so that desired operations can be performed by manipulating the remote commander. The window is formed in a blank portion of and/or between characters/figures inscribed on the cabinet or on a logo plate attached to the cabinet. A light sensor or a light emitter is disposed in a stage posterior to the light receiving window. When the apparatus is applied to a television receiver or a projector embedded in a wall by user's customization in a manner that only a display screen and a frame thereof are seen on the wall, the external design is not spoiled while the command signal from the remote commander can still be inputted properly.