JP-2026076219-A - Method and system for modulating the intensity profile of a laser beam

JP2026076219AJP 2026076219 AJP2026076219 AJP 2026076219AJP-2026076219-A

Abstract

[Problem] A method for modulating the intensity profile of a laser beam. [Solution] The method involves irradiating an acoustic-optical device with a laser to generate an output laser beam having multiple angularly deflected laser beams, capturing an image of the output laser beam, determining the intensity profile of the output laser beam along the horizontal axis from the captured image, and adjusting one or more parameters of the waveform input to the acoustic-optical device in response to the determined intensity profile to generate an output laser beam having a modulated intensity profile. A system having a laser, an acoustic-optical device, an imaging sensor, and a waveform generator, as well as a non-temporary computer-readable storage medium having instructions for implementing the method of the subject, is also described. [Selection Diagram] Figure 3A

Inventors

バール，マシュー
オウズリー，キーガン
ゾウ，ジズオ

Assignees

ベクトン・ディキンソン・アンド・カンパニー

Dates

Publication Date: 20260511
Application Date: 20260115
Priority Date: 20200519

Claims (1)

A method for modulating the intensity profile of a laser in a particle analyzer, The process involves irradiating an acoustic-optical device with a laser to generate an output laser beam containing multiple angle-deflected laser beams, and The process involves capturing an image of the output laser beam, From the captured image, the intensity profile of the output laser beam along the horizontal axis is determined, A method comprising: adjusting one or more parameters of a waveform input to the acousto-optic device in response to a determined intensity profile to generate an output laser beam having a modulated intensity profile.

Description

Photodetection is often used to characterize the components of a sample (e.g., a biological sample) when the sample is used to diagnose a disease or condition. When a sample is irradiated, light can be scattered by the sample, transmitted through the sample, and even emitted by the sample (e.g., by fluorescence). Variations in sample components, such as morphology, absorptivity, and the presence of fluorescent labels, can cause variations in the light scattered, transmitted, or emitted by the sample. To quantify these variations, light is collected and directed towards the surface of a detector. One technique that utilizes photodetection to characterize components within a sample is flow cytometry. The data generated from the detected light can be used to record the properties of components, allowing for the selection of desired materials. A flow cytometer typically includes a sample reservoir for receiving fluid samples, such as blood samples, and a sheath reservoir containing the sheath fluid. A flow cytometer directs the sheath fluid into the flow cell, transferring particles (including cells) from a fluid sample into the flow cell as a cell stream. Within the flow cell, a liquid sheath forms around the cell stream, imparting a substantially uniform velocity to it. The flow cell hydrodynamically focuses the cells in the stream, directing them through the center of the light source within the flow cell. Light from the light source can be detected as scattered light or by transmission spectroscopy, or it can be absorbed by one or more components in the sample and re-emitted as emission. Aspects of this disclosure include methods for modulating the intensity profile of a laser beam. Methods according to specific embodiments include irradiating an acousto-optical device with a laser to generate an output laser beam having multiple angularly deflected laser beams; capturing an image of the output laser beam; determining the intensity profile of the output laser beam along the horizontal axis from the captured image; and adjusting one or more parameters of a waveform input to the acousto-optical device in response to the determined intensity profile to generate an output laser beam having a modulated intensity profile. Also described are systems having a laser, an acousto-optical device, an imaging sensor, and a waveform generator, as well as a non-temporary computer-readable storage medium having instructions for implementing the subject method. In implementing the method described in the subject, one or more parameters of the waveform input to the acousto-optical device are adjusted to modulate the intensity of the output laser beam. In some embodiments, the method includes adjusting one or more tones input to the acousto-optical device. In some cases, the amplitude of the tone is adjusted. In other cases, the frequency of the tone is adjusted. In specific cases, each tone input to the acousto-optical device is formed from a sum of sine waves, and the method includes adjusting one or more parameters of the sine wave of each input tone. For example, for each input tone, the frequency or amplitude of the sine wave may be adjusted. In certain embodiments, the method includes determining the amplitude of each angularly deflected laser beam in the output laser beam and adjusting one or more parameters of the waveform input to the acousto-optical device for each of the angularly deflected laser beams. In some cases, the method includes determining the amplitude of each angularly deflected laser beam in the output laser beam and comparing each determined amplitude with a predetermined threshold intensity. In certain cases, the method includes adjusting the parameters of the waveform input to the acousto-optical device for each angularly deflected laser beam determined to be below the predetermined threshold intensity. If the intensity of an angularly deflected laser beam is determined to be below the predetermined threshold intensity, the method may include adjusting the frequency or amplitude of the tone of the waveform input to the acousto-optical device. In some embodiments, the method includes determining the intensity profiles of multiple angularly deflected light beams along the horizontal axis of the output laser beam. In some embodiments, the intensity profiles are determined by a photodetector. In certain embodiments, an image of the output laser beam is captured by an imaging sensor or beam camera, etc. In some cases, an intensity profile plot is generated from the captured image of the output laser beam, etc. In certain cases, the method includes applying a predetermined threshold to the output laser beam intensity profile plot and identifying angularly deflected beams that fall below the applied predetermined threshold. In some embodiments, the method includes generating an output laser beam having a substantially constant intensity profile along the horizontal axis. In some cases, the parameters of the