9 results about "Optical delay line" patented technology

A signal processing apparatus, a detection apparatus and a terminal device, which relate to the technical field of detection, and are used for reducing the costs and occupied spaces of optical delay lines. The signal processing apparatus comprises a first frequency modulation group (11), a second frequency modulation group (21) and an optical delay line (400); the first frequency modulation group (11) comprises a first frequency modulation photoelectric loop (110), a second frequency modulation photoelectric loop (210) and a polarization control element (300); the second frequency modulation group (21) comprises a third frequency modulation photoelectric loop (310); the polarization control element (300) is connected among the optical delay line (400), a first beam splitting element (112, 212, 312) in each frequency modulation photoelectric loop (110, 210, 310) and a frequency mixer (114, 214, 314) in each frequency modulation photoelectric loop (110, 210, 310), and is used for outputting optical signals (S11, S21, S31) in the three frequency modulation photoelectric loops (110, 210, 310) to the optical delay line (400) in orthogonal polarization directions, and outputting the delayed optical signals (S11 ', S21 ', S31 ') to the mixer (114, 214, 314) in each frequency modulation optoelectronic circuit (110, 210, 310). The signal processing apparatus can achieve the effect that the three frequency modulation photoelectric loops (110, 210, 310) share the same optical delay line (400), and reduce the number of optical delay lines (400) required to be provided in the signal processing apparatus, and the costs and occupied spaces of the optical delay lines (400).

The application discloses a kind of background noise suppression systems of dual optical comb coherent raman spectrum of probe light delay control, by setting the laser that light frequency comb light source module is emitted into probe light and pump light by first beam splitter in probe light delay control module, and setting optical delay line is applied to the probe light with delay amount, utilize the characteristics that the decay time of coherent raman spectrum signal is longer than the decay time of background noise, probe using probe light with delay amount, realize the purpose of inhibiting background noise, it is beneficial to improve the signal-to-noise ratio of dual optical comb coherent raman spectrum measurement system, inhibits spectrum signal distortion.

This invention discloses a delay compensation device, a delay compensation method, and a phased array laser terminal. Multiple transmitting optical paths, a sampling and monitoring module, and a phased array antenna are sequentially connected in communication. Each transmitting optical path includes a first optical delay line and a first high-speed phase shifter. The sampling and monitoring module determines a first delay control parameter and a first phase control parameter, or a second delay control parameter and a second phase control parameter, based on the optical path difference. The first optical delay line performs first optical path difference delay compensation on the laser beam. The first high-speed phase shifter performs first phase difference delay compensation on the laser beam. The phased array antenna performs second optical path difference delay compensation and second phase difference compensation on the laser beam based on the second delay control parameter and the second phase control parameter. In this embodiment, the delay compensation of the laser beam using the first optical delay line, the first high-speed phase shifter, and the phased array antenna solves the phase jump and wavelength dispersion problems in phased array communication and improves communication capacity.

A photonic analog-to-digital conversion (ADC) method and converter based on the optical trapping principle is disclosed. This method utilizes multiple continuous light sources to load sampled analog signals and controls the input of each analog signal to the optical trapping module at equal time intervals via optical delay lines, achieving signal discretization in the time domain. The use of multiple continuous light sources increases the total input power of the photonic ADC system. Furthermore, the multiple optical signals are modulated and delayed by analog signals before being synthesized into a single signal, avoiding the nonlinear effects caused by excessively high total optical power resulting from directly synthesizing multiple continuous light sources. This invention's photonic ADC method based on the optical trapping principle overturns the traditional method of generating pulsed light before photonic sampling, increasing the total input power of the photonic ADC system and effectively offsetting the impact of optical power loss on the conversion accuracy. Based on this method, a high-precision on-chip photonic ADC system can be achieved.

The application discloses a picosecond laser ultrasonic-based metal film plane stress measuring device and method, and the device comprises a femtosecond laser, an optical isolator, a 1 / 2 wave plate and a first polarization beam splitter; the first polarization beam splitter divides the incident laser into pump light and probe light, the pump light passes through a frequency doubling assembly and an electro-optic modulator, and the probe light passes through an adjustable optical delay line and a polarization control element, and the pump light and the probe light are combined at a dichroic mirror; the method comprises the following steps: changing the optical path difference of the pump light and the probe light; collecting the reflectivity change and averaging multiple times; performing background removal and digital filtering processing to obtain a smooth echo characteristic signal; applying a peak searching algorithm to determine the time delay corresponding to the first echo, and combining the known film thickness to calculate the longitudinal wave speed; calibrating the speed under different known stress conditions; establishing a speed-stress mapping relationship to obtain the in-plane residual stress value of the metal film. The application realizes sub-picosecond time, micron-level space and non-contact film stress detection.

The application discloses a microwave multi-dimensional parameter measurement system and method based on differential frequency-time mapping. In the system, after optical pulses pass through an input end dispersion medium to complete pulse expansion, the optical pulses enter a Sagnac loop. Meanwhile, after a microwave signal to be measured is branched by a radio frequency power divider, the microwave signal to be measured is input into two Mach-Zehnder modulators in the loop to modulate the optical pulses. An adjustable optical delay line is arranged between the first Mach-Zehnder modulator and an optical coupler. The modulated optical pulses output by the loop pass through an output end dispersion medium to realize frequency-time mapping, and map the spectrum information to the time domain. After the optical signal is converted into an electric signal by a photoelectric detector, the electric signal is converted into a digital signal by an analog-to-digital converter and is input into a digital signal processor, so that the time, frequency, amplitude and phase information of the microwave signal to be measured are obtained. The application avoids the problems of narrow bandwidth, high loss and poor adjustability of an electronic delay line, and can simultaneously perform high-precision measurement on the time, frequency, amplitude and phase of a multi-carrier microwave signal.

A signal processing apparatus, a detection apparatus, and a terminal device, relating to the technical field of detection, and used for reducing the cost of optical delay lines and the space occupied by the optical delay lines. The signal processing apparatus comprises a first frequency modulation photoelectric loop (110) and a second frequency modulation photoelectric loop (210). The first frequency modulation photoelectric loop (110) and the second frequency modulation photoelectric loop (210) share a mode conversion element (300) and an optical delay line (400). The mode conversion element (300) outputs a first optical signal (S11) in the first frequency modulation photoelectric loop (110) and a second optical signal (S21) in the second frequency modulation photoelectric loop (210) to the optical delay line (400) in different modes, outputs a delayed first optical signal (S11') to a frequency mixer (114) in the first frequency modulation photoelectric loop (110), and outputs a delayed second optical signal (S21') to a frequency mixer (214) in the second frequency modulation photoelectric loop (210). The signal processing apparatus can achieve the effect that a plurality of frequency modulation photoelectric circuits (110, 210) share the same optical delay line (400) by means of mode multiplexing, thereby reducing the number of optical delay lines (400) needing to be provided in the signal processing apparatus, and reducing the volume of the optical delay lines (400) and the space occupied by the optical delay lines (400).

The coherent beam recombination system provides an output recombined beam and comprises: a laser source providing a source beam with linewidth; a beam broadener providing a broadened beam from the source beam; a splitter splitting the broadened beam into a plurality of secondary beams; a plurality of channels coupled to the splitter. Each channel receives a respective secondary beam and provides a respective intermediate beam. Each channel has an optical amplifier, a phase modulator, an optical delay line, and an opto-mechanical element. The CBC system further comprises an optical sensor that provides a detection signal indicative of an intensity of a received optical beam; a focusing optics that receives the intermediate beams, provides the output recombined beam from a first portion of each intermediate beam, and provides a sampled recombined beam to the optical sensor from a second portion of each intermediate beam. The CBC system further comprises a control unit coupled to the optical sensor and the plurality of channels. The control unit comprises a phase-locking module configured to: provide a plurality of phase control signals to the phase modulators; receive the detection signal from the optical sensor, indicative of an intensity of the sampled recombined beam; calculate a cost function from the detection signal, wherein the cost function is a function of the intensity of the sampled recombined beam; perform an optimization algorithm of the cost function, configured to maximise the intensity of the sample recombined beam; and provide a plurality of updated phase control signals, based on a result of the optimization algorithm.

The application provides a kind of middle infrared real-time imaging system, including visible-near infrared light source, frequency doubler, first light splitting component, middle infrared illumination light generating component, first optical delay line, vortex beam generator, first light parametric amplifier, first imaging component, second imaging component and CCD camera.The first light parametric amplifier uses strong femtosecond vortex pulse laser as pump light, and converts middle infrared signal light of middle infrared wave band carrying object information into visible light for detection and recording with high gain.The strong femtosecond vortex pulse laser as pump light provides high optical gain and large spatial frequency bandwidth in imaging, the high gain provides conditions for realizing extremely high sensitivity of photon order, and the large spatial frequency bandwidth ensures micron-level spatial resolution.In addition, vortex pump light realizes vortex phase contrast imaging, further improving image contrast.