Method and device for inducing dual nonlinear photoacoustic signals with a single laser pulse

A nonlinear light and laser pulse technology, which is used in measurement devices, material analysis by optical means, instruments, etc., to achieve the effect of improving signal-to-noise ratio, sensitivity and resolution

Active Publication Date: 2019-04-16
上海他得智能科技有限公司
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The method and device for inducing dual nonlinear photoacoustic signals with a single laser pulse provided by the present invention can solve the problem in the prior art that one laser pulse cannot be used to generate two nonlinear photoacoustic signals

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method and device for inducing dual nonlinear photoacoustic signals with a single laser pulse
  • Method and device for inducing dual nonlinear photoacoustic signals with a single laser pulse
  • Method and device for inducing dual nonlinear photoacoustic signals with a single laser pulse

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0075] The measured object is chosen as a black rubber wire because it has a relatively strong light absorption coefficient and a large thermal diffusion relaxation time. As a comparative observation, a single photoacoustic signal was also generated with short laser pulses. Using 1us laser pulses, such as figure 2 As shown in a, the traditional short laser pulse can only generate a photoacoustic signal, such as figure 2 as shown in c. On the other hand, using 10us laser pulses, such as figure 2 As shown in b, we can observe two photoacoustic signals, such as figure 2 as shown in d. It can be seen that the two photoacoustic signals are respectively generated at the rising edge and falling edge of the laser pulse, and the time delay between them is equal to the width of the pulse (10us). The waveforms of the two photoacoustic signals are highly correlated, but have opposite phases. This is because they come from the same object under test. The first photoacoustic signal...

Embodiment 2

[0079] In order to show that the nonlinear photoacoustic technique proposed in the present invention is superior to the existing linear photoacoustic technique in distinguishing the contrast of different samples, in this example, three different samples (black ink, gold nanorods, IR825 dye) were put into the same plastic thin tube. These samples all have strong and similar linear absorption coefficients under 808nm wavelength laser irradiation. From Figure 5 It can be seen in b that the amplitude of the first photoacoustic signal generated by the three samples due to linear absorption is almost the same (20 mV). However, the magnitude of the second photoacoustic signal caused by nonlinear effects is quite different. Subtracting the amplitudes of the two signals, we can get a comparison diagram of the nonlinear enhancement of the photoacoustic signal of the three samples, Figure 5 as shown in c. It can be seen that the part of nonlinear enhancement can better distinguish ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
wavelengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for inducing double nonlinearity photo-acoustic signals trough a single laser pulse. The method comprises the steps that the single laser pulse is focused to an object to be measured; when the width of the laser pulse is larger than pressure relaxation time of the object to be measured, the object to be measured produces double nonlinearity photo-acoustic signals. The invention further discloses a device for inducing the double nonlinearity photo-acoustic signals trough the single laser pulse. The device comprises a laser pulse output device capable of adjusting width, a focusing lens and an ultrasonic sensor. The laser pulse output device is used for producing a laser pulse, the focusing lens focuses the laser pulse to the object to be measured, the focusing lens is arranged in a cavity of the ultrasonic sensor, the object to be measured is arranged at a port of the cavity of the ultrasonic sensor, and the ultrasonic sensor is used for detecting the double nonlinearity photo-acoustic signals produced through induction of the laser pulse. The problem that a laser pulse cannot produce two nonlinearity photo-acoustic signals in the prior art can be solved, and the photoaccoustic detection and imaging technology sensitivity and resolution ratio can be further improved compared with traditional nonlinearity photo-acoustic technology.

Description

technical field [0001] The invention belongs to the technical field of nonlinear photoacoustic detection and imaging, in particular to a method and device for inducing double nonlinear photoacoustic signals with a single laser pulse. Background technique [0002] Photoacoustic detection and imaging technology is a new hybrid imaging method that has recently developed rapidly in the field of medical imaging. The principle of photoacoustic imaging technology is that when the nanosecond ultrashort laser pulse is irradiated on the measured object, the measured object will absorb part of the light energy, resulting in a transient temperature rise, resulting in transient vibration of thermal expansion and cold contraction. Such vibration can excite ultrasonic waves, that is, photoacoustic signals. If the objects to be measured are different, the intensity of the generated ultrasonic waves will also be different. Since the amplitude of the photoacoustic signal is linearly proporti...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): G01N21/17
CPCG01N21/1702
Inventor 高飞段丽莎
Owner 上海他得智能科技有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap