Abstract: An optical fiber chromatic dispersion distribution measuring apparatus for measuring the chromatic dispersion distribution of an optical fiber under test comprising two light sources at least one of which can change wavelength thereof, wherein light beams having different wavelengths from each other and emitted from the two light sources are inputted to the optical fiber under test to measure a four-wave mixing light beam generated by interaction between the two light beams by optical time domain reflectometer (OTDR); wherein an optical bandpass filter having a fixed center wavelength is provided at a previous stage of the optical time domain reflectometer (OTDR); and wherein a coherence controller for controlling coherence of at least one of the light beams outputted from the two light sources.

Abstract: In order to improve a measuring precision in case of measuring properties of the optical fiber to be measured, in accordance with returned lights which have wavelengths different from each other, detection is carried out with respect to the returned lights of the wavelengths different from each other, at a timing based on difference of propagation rates between the returned lights in the optical fiber to be measured, and error between the returning points is compensated with respect to each returned light, in the optical pulse testing device for inputting the optical pulse to the optical fiber to be measured, to detect returned lights which have wavelengths different from each other and which are returned back from passing points in the optical fiber to be measured, respectively, in order to measure the properties of the optical fiber to be measured, in accordance with detection results of the returned lights.

Abstract: An IC test system comprises: a test pattern signal applying section for applying a test pattern signal to an IC to be tested, in accordance with a test program; a simulation section for simulating an operation of the test pattern signal applying section in accordance with a simulation program; and a management device which is connected detachably with the test pattern signal applying section, for managing the operation of the test pattern signal applying section and an operation of the simulation section in accordance with a management program, for storing information about each operation of the test pattern signal applying section and the simulation section, and for managing one of the information about the operation of the simulation section and the information about the operation of the test pattern signal applying section in accordance with the other information.

Abstract: An apparatus and method for heating semiconductor devices (DUTs) having a variety of package shapes. The apparatus has a plurality of trays on which DUTs are mounted. A heating chamber with a plurality of stages, house the tray. A tray moving mechanism moves the trays so as to be disposed within the heating chamber and outside of the heating chamber. The method has the steps of supplying the DUTs on a tray, heating the DUTs supplied on each tray, and relocating and measuring the DUTs.

Abstract: Wavelength dependent measurement is made by launching light into an object 8 to be measured and receiving transmitted light from the object 8 while continuously changing wavelengths of output light. Next, peak wavelength detection processing for detecting a wavelength at the time when loss or gain of the transmitted light from the object 8 becomes maximum based on a wavelength dependent measurement result is performed. Then, polarization dependent loss measurement processing for measuring polarization dependent loss of the object 8 is performed by measuring the transmitted light from the object 8 while launching light of a measurement wavelength detected into the object 8 and randomly changing a polarization state of the light. Further, a control circuit processes associating a wavelength dependent analysis result with a PDL measurement result, and displays its result on a display part 2.

Abstract: Light under measurement whose wavelength is continuously swept is incident on fiber-optic Etalon. The fiber-optic Etalon transmits the light under measurement each time the wavelength of the light under measurement satisfies specific conditions. A PD detects the transmitted light of the fiber-optic Etalon and outputs the intensity of the light under measurement. A counter counts the number of peaks of the output of the PD. A CPU calculates the wavelength of the light under measurement based on the count value of the counter.

Abstract: A phase delay characteristic measuring apparatus includes an in-phase component calculating means for outputting a correlation value between input sampling data of the input signal and the output signal and ideal sine waveform data as a baseband I signal (in-phase component), a quadrature component calculating means for outputting a correlation value between the input sampling data of the input signal and the output signal and ideal cosine waveform data as a baseband Q signal (quadrature component), a phase angle calculating means for outputting phase angles of the input signal and the output signal based on the baseband I signal and the baseband Q signal, and a phase delay calculating means for calculating an amount of phase delay of the tested device from the phase angles of the input signal and the output signal.

Abstract: A method is provided of setting grids and/or markers on a screen of a display unit of a measuring apparatus. First, a mode of the apparatus is changed into a mode of setting the grids and/or the markers. Then, the grid and/or the marker serving as a reference is set. Then, a plurality of grids and/or markers are set, each of which provides an arbitrary interval with respect to the grid and/or the marker serving as reference.

Abstract: A wavelength dispersion distribution measuring apparatus of an optical fiber includes light signal generation section 1, 2 for generating two light signals with different wavelengths, section 3, 4 for combining the signals and shaping a light pulse signal, directional coupling section 6 for inputting the light pulse signal to one end or the other end of a measured optical fiber and also branching total back-scattered light from the measured optical fiber, wavelength extraction section 9 for passing only a wavelength component of one of four-wave mixed light generated by interaction of two wavelengths launched, measuring section 10 for measuring wavelength dispersion distribution data, changeover section 12-1 to 12-3 for switching the input side and the terminal side of the light pulse from one end to the other end of the measured optical fiber, and calculation section 11 for performing superimposition processing of two measured results associated with the switching.

Abstract: A monitor circuit 1 incorporates a switch 4, a switch 5, a counter 6, a high-speed RAM 7, a counter 8 and a low-speed RAM 9. The monitor circuit 1 is a circuit structured such that the switch 4 and the switch 5 are switched in accordance with the level of an input signal to cause data for one row which concerns SOH in the frame of STM which is received as received data 2 to be stored in the high-speed RAM 7. In a period in which data concerning payload is received, a process for storing data for one row which concerns the SOH stored in the high-speed RAM 7 in the low-speed RAM 9 is repeatedly performed. Thus, data concerning all of the SOH which constitute one frame of the STM is extracted so as to output the extracted data items as an output signal 10.

Abstract: In a frequency spectrum analyzer (2) which receives a modulation signal previously measures the frequency (F). A synchronous detection frequency (B) is determined on the basis of the frequency (F). An adder (7) obtains the difference (G) between the synchronous detection frequency (B) and the reference frequency (C). From an I signal and a Q signal which are obtained by performing synchronous detection by using the synchronous detection frequency (B), a frequency error detector (6) obtains a frequency error (E) by the phase trajectory method. An adder (8) adds the difference (G) and the frequency error (E) to obtain a frequency error.

Abstract: A motion picture code evaluator evaluates a transmitted motion picture based on losses caused by a transmission means. The evaluator includes means for testing the frame header of the motion picture code and determining the presence/absence of an error in the frame header to calculate the frame loss ratio per predetermined time. The evaluator further includes means for extracting a motion picture coding parameter contained in the frame header and detecting a variation in the motion picture coding parameter in the predetermined time, and means for summing the motion picture coding parameter and the motion picture coding parameter weighted by the variation in a motion picture coding parameter in the predetermined time to calculate an ideal motion picture information amount in a predetermined time. The motion picture code evaluator thereby obtains an actual motion picture information amount by multiplying the ideal motion picture information amount by 1-frame loss ratio.

Abstract: Lenses 102, 103, and 104, a diffraction grating 105, a mirror 106, a light isolator 107, an arm 108, a pulse motor 109, and a pulse motor 110 operate in conjunction for mechanically roughly adjusting the wavelength of laser light generated by an LD 101, and the wavelength of laser light generated by the LD 101 is electrically finely adjusted in a wavelength adjustment section 30.

Abstract: A photocoupler 3 splits the light from a low-coherence light source 1 into measuring light DL and local oscillator light KL. A photocoupler 5 receives measuring light DL arid is input to an optical circuit 7 to be measured. The photocoupler 5 splits the reflected light RL. A polarization controller 9 controls the state of polarization of the reflected light RL as split by the photocoupler 5. A photocoupler 13 allows local oscillator light KL to be incident on a reflector mirror 16 and splits local oscillator light KL. A photocoupler 11 combines the reflected light RL as controlled in the state of polarization by the polarization controller 9, with the local oscillator light KL.

Abstract: In order to improve a measuring precision in case of measuring properties of the optical fiber to be measured, in accordance with returned lights which have wavelengths different from each other, detection is carried out with respect to the returned lights of the wavelengths different from each other, at a timing based on difference of propagation rates between the returned lights in the optical fiber to be measured, and error between the returning points is compensated with respect to each returned light, in the optical pulse testing device for inputting the optical pulse to the optical fiber to be measured, to detect returned lights which have wavelengths different from each other and which are returned back from passing points in the optical fiber to be measured, respectively, in order to measure the properties of the optical fiber to be measured, in accordance with detection results of the returned lights.

Abstract: The invention can be easily applied to various contacts irrespective of the length of time needed for replacing ICs with other ICs relative to the contact. An IC handler comprises contact cleaning chips made of a material including polishing particles in the same shape as an ICs wherein a transfer attachment is removed from the contacts when contact cleaning chips are conveyed to the contacts so as to contact the contacts, then the contacts are taken out.

Abstract: A variable slit width device for a spectroscope which can be used in a narrow space, be widely variable, and be set in slit width with high accuracy. The variable slit width device includes a pair of freely rotatable rotary parts for pressing inclined guide parts of a pair of slit holders, pressing parts for supporting the pair of rotary parts, and linear guides having guide parts formed at the lower surfaces thereof and extending horizontally in a direction crossing with guide rails at right angles. The pressing parts are fixed to the linear guides, the guide rails are fitted to the guide parts of the linear guides, feed nuts are fixed to the pressing parts, feed screws are engaged with the feed nuts. Bearings are provided for rotatably supporting the feed screws, preload springs for preloading the feed nuts and the feed screws, a slit driving part for rotatably driving the feed screws, and a housing part for fixing thereto the guide rails, the bearings and the motor.

Abstract: The invention provides a structure that does not employ complicated and large-scale control circuits or control memory, minimizes the circuits for real time processing, and allows the use of refresh memory. The invention provides a test clock (8-1) comprising a data processing apparatus (1-1) provided for each electrode pin of the measured device (11), a memory (2-1) that carries out reading and writing of the test pattern data and the like, a first-in-first-out element (4-1) that executes queue processing of the data read out from the memory, a delay circuit (5-1) that delays the output signal of the first-in-first-out element, and a measured device driver (6-1) that inputs into the electrode pin the output signal of the delay circuit, and in which the data processing apparatus (1-1) of adjacent test blocks are connected into a loop via the input-output circuit (3-1).

Abstract: A CRC code calculation circuit for calculating a CRC code from byte parallel data which is variable-length data. In a CRC code calculation circuit 10 for calculating a CRC code from four-byte parallel data having a residual portion in a final stage, a four-byte parallel CRC code calculation circuit 2calculates a CRC code in parallel from the four-byte parallel data except the final stage. A byte serial conversion circuit 3 converts data of the final stage into serial data. A one-byte serial CRC code calculation circuit 4 calculates a CRC code in serial from the serial data converted by the byte serial conversion circuit 3 using a calculated result of the four-byte parallel CRC code calculation circuit 2 as an initial value.

Abstract: A low coherent reflectometer uses low coherent beams for measurement of refletance and refleting positions with respect to a measured optical circuit which includes a reflecting point. The low coherent beams are branched to produce measurement beams (DL) and local beams (KL), so that the measurement beams are introduced into a first optical path, which includes a dispersion shifted fiber, towards the measured optical circuit, while the local beams are introduced into a second optical path which includes a spatial optical path terminated by a reflecting mirror. Refleted measurement beams (RL) and reflected local beams are combined together to produce combined beams, which are subjected to processing and analysis.