6 results about "Inversion pulse" patented technology

This application provides an inertial measurement method and system based on atomic interferometry. The method includes: controlling a first atomic beam and a second atomic beam to exit into an interference region, and sequentially interacting with three pulse beams in the interference region to detect the corresponding momentum transfer probability signals. The exit directions of the first and second atomic beams intersect and are symmetrical about the quantization axis. The effective pulse vector directions of the three pulse beams are adjusted so that the adjusted effective pulse vector directions are opposite to those of the original three pulse beams. The first and second atomic beams are then controlled to exit into the interference region, and sequentially interact with the adjusted three pulse beams in the interference region to detect the corresponding momentum transfer probability signals. Based on the four momentum transfer probability signals, the inertial measurement result is determined. Thus, by reversing the effective pulse vector direction, the interference area is reversed, effectively suppressing noise and drift terms unrelated to the effective pulse vector direction.

The invention discloses a low-field NMR relaxation time rapid measurement method, and the method comprises the steps: designing an IR-bSSFP pulse sequence which comprises a 180-degree reversal pulse and an excitation pulse sequence, and enabling the flip angle of a radio frequency excitation pulse in the excitation pulse sequence to be a pseudo-random flip angle; the radio-frequency phases of the adjacent radio-frequency excitation pulses are linearly changed by a fixed phase increment; based on the IR-bSSFP pulse sequence, obtaining a component MRF signal sequence of a measured object, and simulating a magnetization vector evolution process to obtain a dictionary matrix; matching the component MRF signal with a dictionary matrix pattern in combination with a smooth constraint term to obtain corresponding longitudinal relaxation time and transverse relaxation time; the invention also discloses low-field NMR relaxation time rapid measurement equipment, which comprises a pulse sequence construction module, a dictionary generation module and a mode matching module. Multi-parameter information can be obtained through single scanning, the measurement time is remarkably shortened, the experiment complexity is reduced, and the precision and repeatability of a measurement result are improved.

The application relates to a method for determining inversion time in blood vessel imaging, a magnetic resonance imaging method and a device. The method for determining inversion time in blood vessel imaging comprises the following steps: selecting an imaging position from a blood vessel imaging area; at the imaging position, collecting at least two blood vessel images with different inversion times by using an inversion time searching technology; obtaining an inversion time corresponding to a blood vessel image with optimal blood vessel display; and determining a time point for setting a longitudinal magnetization to zero according to the inversion time corresponding to the blood vessel image with optimal blood vessel display. The magnetic resonance imaging method comprises the following steps: determining an inversion time based on the method for determining inversion time in blood vessel imaging; applying a regional selection inversion pulse at an imaging position; and applying a target imaging sequence at the imaging position after the inversion time to obtain a target magnetic resonance image. The method can optimize the inversion time, thereby obtaining optimal blood vessel display.

The application provides a magnetic resonance angiography method and a magnetic resonance imaging device, the magnetic resonance angiography method comprising: for each magnetic resonance image to be generated in a magnetic resonance image sequence, sequentially generating a layer selection saturation pulse signal and N inversion pulse signals in a preset time period corresponding to the magnetic resonance image and in at least an imaging region of a target object, the N inversion pulse signals being used for performing a first inversion operation on tissues in the at least imaging region; after or simultaneously with performing the first inversion operation on the tissues in the at least imaging region by using an (N-i+1)th inversion pulse signal, and before performing the first inversion operation on the tissues in the at least imaging region by using an (N-i)th inversion pulse signal, performing a second inversion operation on blood in a labeling region; collecting a magnetic resonance signal of the tissues in the imaging region, and generating the magnetic resonance image. In the above scheme, the total time consumption of the magnetic resonance imaging process is shorter, and the imaging efficiency is significantly improved.

An electronic device includes: a sensor layer including a plurality of electrodes arranged in “n” rows and “m” columns; and a sensor driver configured to drive the sensor layer, and wherein the plurality of electrodes include: a plurality of electrodes configured to receive a driving pulse signal located within one of the “m” columns; and a plurality of inversion electrodes configured to receive an inversion pulse signal different from the driving pulse signal, and wherein the sensor driver is configured to determine a number of the plurality of inversion electrodes based on a location of the plurality of electrodes, and wherein, the “n” and the “m” are natural numbers.