LASER-INDUCED ULTRASONIC WAVE APPARATUS AND METHOD

• US 20130303909A1
• Filed: 05/03/2013
• Published: 11/14/2013
• Est. Priority Date: 05/03/2012
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Woon-bae, Kim, Jong-seok, Yoon, Yong-seop, KANG, Sung-Chan
• Granted Patent: US 10,251,559 B2
• Time in Patent Office: Days
• US Class Current: 600/443
• CPC Class Codes: A61B 5/0035 adapted for acquisition of images from more than one imaging mode, e.g. combining MRI and optical tomography
• CPC Class Codes: A61B 5/0095 by applying light and detecting acoustic waves, i.e. photoacoustic measurements
• CPC Class Codes: A61B 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: G01N 2291/02475 Tissue characterisation
• CPC Class Codes: G01N 29/2418 using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046
• CPC Class Codes: G10K 15/046 using optical excitation, e.g. laser bundle

Abstract

Laser-induced ultrasonic wave apparatuses and methods of generating images using the same. The laser-induced ultrasonic wave apparatus includes a laser source which irradiates a laser beam to a target object and a thermoelastic material; a thermoelastic material which converts the laser beam to a first ultrasonic wave and irradiates the first ultrasonic wave to the target object; and a receiving unit which receives an echo acoustic wave of the first ultrasonic wave and receives a second ultrasonic wave generated by the target object due to the laser beam.

Claims

1. A laser-induced ultrasonic wave apparatus, the apparatus comprising:

a laser source to irradiate a target object and a thermoelastic material with a laser beam;

the thermoelastic material to generate a first acoustic wave based upon the irradiation of the thermoelastic material by the laser beam, and to transmit the first acoustic wave to the target object; and

a receiving unit to receive and transduce an echo acoustic wave of the first acoustic wave, as reflected from the target object, and receive and transduce a second acoustic wave generated by the irradiation of the target object by the laser beam.

2. The laser-induced ultrasonic wave apparatus of claim 1, further comprising at least one image processor to simultaneously generate a first image based on the received second acoustic wave and a second image based on the received echo acoustic wave,

wherein the first image is generated to be a photoacoustic image for functional analysis of the target object and the second image is generated to be an anatomical image for acoustic analysis of at least the target object.

3. The laser-induced ultrasonic wave apparatus of claim 2, further comprising:

a user interface;

a display unit; and

a controller to control the at least one image processor to output at least one of the first image and the second image to the display unit based upon a user input detected by the user interface.

4. The laser-induced ultrasonic wave apparatus of claim 1, further comprising a controller to selectively change a pulse width of the laser beam based on properties the target object, wherein the thermoelastic material is configured to generate respective acoustic waves with different wavelengths based on the selectively changed pulse width of the laser beam.

5. The laser-induced ultrasonic wave apparatus of claim 1, further comprising a controller to selectively change a pulse width of the laser beam based on properties the target object, wherein the thermoelastic material is configured to generate respective acoustic waves with different pressure magnitudes based on the selectively changed pulse width of the laser beam.

6. The laser-induced ultrasonic wave apparatus of claim 1, further comprising a controller to selectively change a fluence of the laser beam based on properties the target object, wherein the thermoelastic material is configured to generate respective acoustic waves with different pressure magnitudes based on the selectively changed fluence of the laser beam.

7. The laser-induced ultrasonic wave apparatus of claim 1, wherein the laser-induced ultrasonic wave apparatus is configured to split the laser beam into a first laser beam and a second laser beam that both maintain same characteristics as the laser beam, wherein the first laser beam is optically directed to irradiate at least a portion of the target object distinct from the second laser beam being optically directed to irradiate at least a portion the thermoelastic material.

8. The laser-induced ultrasonic wave apparatus of claim 1, wherein the laser source simultaneously irradiates at least a portion of the target object with the laser beam and at least a portion of the thermoelastic material with the laser beam.

9. The laser-induced ultrasonic wave apparatus of claim 1, further comprising a controller to control the laser source to selectively irradiate only the target object with the laser beam during a first time period and irradiate only the thermoelastic material with the laser beam during a second time period, wherein the first time period and the second time period are sequential in time and occur while the receiving unit is enabled to receive and transduce the echo acoustic wave and the second acoustic wave.

10. The laser-induced ultrasonic wave apparatus of claim 9, wherein the controller controls the laser source to generate the laser beam to have respectively different characteristics during the first time period than during the second time period based on properties the target object.

11. The laser-induced ultrasonic wave apparatus of claim 1, further comprising a controller to selectively change characteristics of the laser beam to change a center frequency of the first acoustic wave generated by the thermoelastic material based on properties the target object.

12. The laser-induced ultrasonic wave apparatus of claim 1, wherein the target object is a tissue, within a human body, having an absorption rate smaller than an absorption rate of the thermoelastic material.

13. The laser-induced ultrasonic wave apparatus of claim 1, wherein a pulse width of the laser beam is nano-sized or pico-sized.

14. The laser-induced ultrasonic wave apparatus of claim 1, wherein the thermoelastic material is formed of at least one of a metal, a semiconductor material, a carbon-based material, and a polymer material.

15. The laser-induced ultrasonic wave apparatus of claim 1, wherein the thermoelastic material layer is formed as a thin-film having a thickness less than respective wavelengths of the echo acoustic wave and the second acoustic wave propagating from the target object.

16. The laser-induced ultrasonic wave apparatus of claim 1, wherein the receiving unit comprises at least one transducer to perform the transducing of the received echo acoustic wave and the transducing of the received second acoustic wave to respective electric signals, wherein the at least one transducer includes at least one of a piezoelectric micromachined ultrasonic transducer (pMUT), capacitive micromachined ultrasonic transducer (cMUT), magnetic micromachined ultrasonic transducer (mMUT), and optical ultrasonic wave detector.

17. The laser-induced ultrasonic wave apparatus of claim 1, wherein the thermoelastic material and the receiving unit are embodied together as a single probe.

18. The laser-induced ultrasonic wave apparatus of claim 17, wherein the thermoelastic material and the receiving unit are arranged in the single probe element in a configuration so when the laser beam is incident on the single probe element the thermoelastic material is enabled to be irradiated by the laser beam and incidence of the laser beam on the receiving unit is minimized.

19. The laser-induced ultrasonic wave apparatus of claim 17, wherein a substrate is arranged between the thermoelastic material and the receiving unit in the single probe element.

20. The laser-induced ultrasonic wave apparatus of claim 17, wherein the thermoelastic material and the receiving unit are arranged in the single probe element so the first acoustic wave generated by thermoelastic material propagates through the receiving unit before propagating to the target object.

21. The laser-induced ultrasonic wave apparatus of claim 1, wherein the laser source irradiates the target object and the thermoelastic material simultaneously with the laser beam.

22. The laser-induced ultrasonic wave apparatus of claim 1, further comprising:

a first signal processing unit to generate a first image based on electric signals derived from the received echo acoustic wave;

a second signal processing unit to generate a second image based on electric signals derived from the received second acoustic wave; and

an image combining unit to generate a third image by combining the first image and the second image.

23. A laser-induced ultrasonic wave method, the method comprising:

irradiating a target object and a thermoelastic material with a laser beam;

receiving and transducing an echo acoustic wave, from the target object, as a reflection of a first acoustic wave transmitted to the target object from the thermoelastic material upon the thermoelastic material being irradiated by the laser beam; and

receiving and transducing a second acoustic wave transmitted from the target object upon the target object being irradiated by the laser beam.

24. The laser-induced ultrasonic wave method of claim 23, further comprising simultaneously generating a first image based on the received second acoustic wave and a second image based on the received echo acoustic wave,

wherein the first image is generated to be a photoacoustic image for functional analysis of the target object and the second image is generated to be an anatomical image for acoustic analysis of at least the target object.

25. The laser-induced ultrasonic wave method of claim 24, further comprising selectively displaying at least one of the first image and the second image based upon a user input to a user interface.

26. The laser-induced ultrasonic wave method of claim 23, wherein the target object is a tissue within a human body having an absorption rate smaller than an absorption rate of the thermoelastic material.

27. The laser-induced ultrasonic wave method of claim 23, wherein the thermoelastic material layer is formed as a thin-film having a thickness less than respective wavelengths of the echo acoustic wave and the second acoustic wave propagating from the target object.

28. The laser-induced ultrasonic wave method of claim 23, wherein the thermoelastic material and a receiving unit, performing the receiving of the echo acoustic wave and the second acoustic wave, are embodied together as a single probe element.

29. The laser-induced ultrasonic wave method of claim 23, wherein the target object and the thermoelastic material are simultaneously irradiated with the laser beam.

30. The laser-induced ultrasonic wave method of claim 23, further comprising:

generating a first image based on electric signals derived from the received echo acoustic wave;

generating a second image based on electric signals derived from the received second acoustic wave; and

generating a third image by combining the first image and the second image.