10 results about "Autocorrelator" patented technology

An autocorrelator and a pulse amplifying device including the same are provided. The autocorrelator includes a parabolic mirror configured to transmit and reflect pulse laser beam, a prism on one side of the parabolic mirror and configured to split the pulse laser beam, a first lower retro-reflector under the prism and provided at a first distance from the prism to reflect a portion of the pulse laser beam, a first upper retro-reflector on the prism, provided at a second distance different from the first distance from the prism, and configured to reflect another portion of the pulse laser beam to generate a first time difference between pulses of the pulse laser beam upper retro-reflector, and a first sensor under the parabolic mirror and configured to receive the pulse laser beam to detect a pulse width of the pulse laser beam.

A N-channel interleaved analog-to-digital converter (ADC) adds a variable delay to the input sampling clock of each ADC. During calibration, each variable delay is edited by a successive approximation register (SAR) to minimize the time phase mismatch between channels. An autocorrelator generates a sign of a correlation error for a pair of ADC digital outputs. The SAR bits are tested using the correlation sign to determine when to add or subtract the SAR bits. Calibration is first performed in a binary tree first layer of a multiplexed correlator. Then, the deviation between more distant pairs and groups is calibrated in higher layers of the binary tree using an autocorrelator whose inputs are multiplexed from the ADC output groups to the binary tree of the multiplexed correlator. The binary tree of the multiplexed correlator can include bypassers for odd non-binary values of N. The sampling clock and component time phase mismatch between two adjacent channels and more distant channels is reduced to 1 LSB.

The invention belongs to the technical field of pulse characteristic measurement, and relates to an on-chip integrated single autocorrelator and a measurement method thereof. The autocorrelator comprises an SOI substrate, a photonic crystal waveguide is formed on the SOI substrate through etching, and an insulating layer, an indium selenide layer and a chromium gold electrode array are sequentially arranged on the photonic crystal waveguide; the photonic crystal waveguide is composed of a straight waveguide area in the middle area and photonic crystal areas on the two sides. The chromium-gold electrode array is composed of a plurality of pairs of chromium-gold electrodes which are arranged at equal intervals in the photonic crystal waveguide direction, and each pair of chromium-gold electrodes serve as a source electrode and a drain electrode respectively; a back gate electrode is arranged on an unetched region of the SOI substrate; during measurement, a p-i-n homojunction is formed in the indium selenide material; the source electrode is connected with the p-type region of the indium selenide layer, the drain electrode is connected with the n-type region of the indium selenide layer, and the indium selenide p-i-n homojunction photoelectric detector is formed by the source electrode and the drain electrode. The problem that an existing autocorrelator is difficult to integrate and cannot meet actual requirements is solved.

The utility model discloses an autocorrelator, which belongs to the field of laser measurement and comprises a base, a plurality of reflectors, a plurality of wave plates, a first right-angle reflector assembly, a second right-angle reflector assembly, a wafer, a lens and a power meter. Wherein the wafer is installed on the base through the first adjusting support, and the first right-angle reflector assembly and the second right-angle reflector assembly are installed on the base through the two second adjusting supports respectively; the first adjusting support comprises a support body, a wafer base and a locking piece, the wafer base is rotationally arranged on the support body, and the locking piece is used for limiting rotation of the wafer base. The optical path structure is ingenious in design, and can detect and obtain clean self-correlation signals; the positions of the wafer and the two right-angle reflectors can be adjusted through the first adjusting support and the second adjusting support respectively, noise caused by interference signals can be reduced through fine adjustment, the measurement accuracy of the autocorrelator is improved, the light path adjusting difficulty of the autocorrelator is reduced, and time spent on light path adjusting is saved.

The present invention relates to an imaging spectrometer (10) comprising: - an entrance slit (11) for receiving radiation over a range of wavelengths, - an image detector resolved in two directions, - a spherical mirror (12) with focus F positioned opposite said entrance slit (11), said entrance slit (11) being positioned at the focus F of said spherical mirror (12), - a spectrally dispersive optical assembly (17) for dispersing said radiation as a function of wavelength and focusing it into a detection plane of the image detector, - an extraction mirror (16) for directing the radiation from the spherical mirror (12) onto the spectrally dispersive optical assembly (17), said entrance slit (11) and said spherical mirror (12) being arranged so that the radiation is incident on said spherical mirror (12) at an angle of incidence between ]0.8°], or more preferably ]0.2°]. and even more preferentially around or equal to 1°.

The application provides a self-correlation instrument optical system and a laser pulse width measuring device. The self-correlation instrument optical system comprises an optical path difference generating module, a self-correlation signal generating module and a self-correlation signal receiving module. The optical path difference generating module comprises an optical path adjusting sheet and a Fresnel double prism, which are used for dividing the laser to be measured into two beams of pulse laser with different delays and intersecting at a non-collinear included angle. The self-correlation signal generating module comprises a frequency doubling crystal and a filter sheet, which are used for frequency doubling conversion of the pulse laser, generation of a self-correlation signal and filtering. The self-correlation signal receiving module comprises a CCD module, which is used for receiving an intensity signal of the self-correlation signal and converting the intensity signal into a self-correlation function image for output. The self-correlation function image is used for calculating the pulse width of the laser to be measured through image analysis. The problems that the existing technology is difficult to build and the size of the non-collinear included angle is not easy to adjust due to the use of multiple mirrors are solved.

According to the femtosecond laser autocorrelator with the automatic calibration function and the measuring method thereof, the femtosecond laser autocorrelator has the advantages of being high in measuring speed, high in precision, easy and convenient to operate and small in size, the inherent stability of a light path is fundamentally improved through an integrated light-machine unit, and the measurement accuracy is improved. The light path state sensing unit realizes real-time in-situ monitoring of multiple parameters such as light beam quality and element poses, the adaptive optical unit can dynamically compensate wavefront distortion and optimize phase matching, and the intelligent control processing unit drives the whole system to complete an intelligent process from automatic optimization calibration, signal acquisition processing to pulse reconstruction calculation. Through the combined action of the characteristics, the inherent defects that a traditional instrument depends on manual adjustment, is easily interfered by the environment, is low in measurement efficiency, is insufficient in stability and the like are effectively overcome, and the femtosecond laser pulse measuring device is particularly suitable for rapid, accurate and reliable measurement requirements on femtosecond laser pulses in laboratories and industrial sites.

An optical waveform measurement device 1 comprises a light source 10, a waveform generation unit 20, a measurement unit 30, and a computation unit 40. On the basis of a light pulse outputted from the light source 10, the waveform generation unit 20 generates and outputs target light for which a time waveform is to be measured and a reference single light pulse. The target light and the reference single light pulse are inputted into the measurement unit 30 at a time interval that is longer than the time widths of the light. The measurement unit 30 is an autocorrelator and measures the shape of the autocorrelation of a time waveform for light that includes the target light and the reference single light pulse. The computation unit 40 finds a time waveform for the target light on the basis of the portion of the autocorrelation shape that represents the autocorrelation between a time waveform for the target light and a time waveform for the reference single light pulse. The present invention thereby provides a device and a method that make it possible to easily and accurately measure a time waveform for target light.

The invention discloses a beam splitting synchronization assembly for a single-emission autocorrelator and the single-emission autocorrelator, and relates to the technical field of laser pulse measurement. The beam splitting synchronization assembly comprises a dihedral corner reflector. The dihedral corner reflector comprises a first reflecting surface and a second reflecting surface which intersect with each other. The surface of the first reflecting surface and the surface of the second reflecting surface are provided with coating films based on metal materials. Laser to be measured enters the ridge line of the dihedral corner reflector, passes through the first reflecting surface and then is emitted as first beam splitting laser, and passes through the second reflecting surface and then is emitted as second beam splitting laser; the angular bisector of the included angle between the propagation direction of the first split laser and the propagation direction of the second split laser is perpendicular to the incident optical axis of the laser to be measured. The beam splitting synchronization assembly does not need an additional time synchronization mechanism such as a delay line, and the characteristic of almost zero dispersion of the to-be-measured laser in a bandwidth range can be ensured by arranging a coating film based on a metal material, so that introduction of additional material dispersion and angular dispersion during beam splitting and synchronization of the to-be-measured laser is avoided.

This application relates to the field of femtosecond laser technology, and discloses a method, apparatus, and medium for diagnosing and correcting the dispersion distribution of chirped fiber gratings. The method involves constructing a chirped pulse amplification system; adjusting the pulse compressor so that the compressed pulse, as displayed by an autocorrelator, exhibits the narrowest pulse width under the current state; inserting a laterally movable narrowband filter into the diffraction path of the pulse compressor, sequentially blocking different wavelength spectral components by moving the filter laterally, and using an autocorrelator to monitor the time-domain shape of the compressed pulse after blocking different spectral components in real time; determining the corresponding spectral component as the error spectral component causing the dispersion distribution mismatch based on the time-domain shape of the compressed pulse; and correcting the dispersion distribution of the chirped fiber grating in the grating region corresponding to the determined error spectral component based on the determined error spectral component. By scanning the spectral components, the problem of "perceptible but difficult to locate" high-order dispersion errors is solved.