Light, sound and light sheet bimodal imaging system

Abstract

The utility model discloses an optical acousto-optic sheet bimodal imaging system, and relates to the technical field of microscopic imaging. Continuous laser; the pulse laser and the continuous laser irradiate on the dichroscope to generate reflected pulse laser and transmitted continuous laser respectively, and the reflected pulse laser and the transmitted continuous laser are combined to form a laser beam; the galvanometer reflects the laser beam to form scanning laser; the scanning objective lens transmits the scanning laser to form a scanning light beam, and the sample generates ultrasonic waves and fluorescent light under excitation of the reflected pulse laser and the transmitted continuous laser; the ultrasonic detector is used for collecting ultrasonic waves and forming corresponding ultrasonic signals; and the camera is used for collecting fluorescence to form a corresponding fluorescence signal. In the application, the pulse laser for exciting the ultrasonic wave and the continuous laser for exciting the fluorescence are highly overlapped on the light path, so that the problem of huge system size caused by independent design of the light path is avoided.

Description

Technical Field

[0001] The present application relates to the field of microscopic imaging technology, and in particular to a photoacoustic and light sheet dual-modal imaging system. Background Art

[0002] Photoacoustic microscopy is an imaging method based on the photoacoustic effect. It can break through the diffraction limit of traditional optical imaging and maintain high resolution while achieving a deeper imaging depth. For example, the lateral resolution of optically resolved photoacoustic microscopy can reach several micrometers to hundreds of nanometers, and the imaging depth can reach several millimeters. With the development of laser technology, ultrasonic detection technology, and optomechanical scanning technology, a variety of photoacoustic microscopy techniques have gradually been developed, such as high-resolution and large-field photoacoustic imaging technology based on mechanical scanning, and high-resolution and fast photoacoustic imaging technology based on MEMS (microelectromechanical system) / Galvomirror scanning. The purpose is to maintain high resolution while increasing the imaging rate or imaging field of view, extract biological vascular dynamics information, or observe larger areas of biological tissues, and is widely used in research or clinical medicine such as early diagnosis of tumors, detection of cardiovascular and cerebrovascular diseases, and detection of neurodegenerative diseases. However, due to the natural mutual constraints between imaging resolution, field of view, and speed, it is difficult to achieve high-speed and large-field photoacoustic imaging, which limits its further development.

[0003] Light sheet mesoscopic imaging technology is a three-dimensional microscopic imaging technology with important application value in biomedicine and other fields. It mainly adopts orthogonal optical path design, uses a thin light sheet to excite the sample from the side, and uses a microscope objective and a digital camera to capture the two-dimensional fluorescence image of the sample in the direction perpendicular to the light sheet. By axially scanning the light sheet or moving the sample to image the surface one by one, tomographic images at different depths are obtained, and finally the three-dimensional reconstruction of the sample is realized. Its main technical advantages are: large field of view and high speed. It uses a high QE (quantum efficiency) CCD (charge-coupled device) or sCMOS (scientific-grade complementary metal oxide semiconductor) camera for surface imaging. The light sheet is exposed through the sample once, and all the information of the sample on this plane can be obtained, which greatly improves the imaging speed and image signal-to-noise ratio, and can quickly obtain images with a large field of view. Low light damage. Compared with traditional fluorescence illumination technology, the light is emitted from the side of the sample and only illuminates the sample tissue on the plane. The phototoxicity can be reduced many times, and long-term three-dimensional imaging of living biological samples can be performed under conditions closer to the physiological state. High contrast and high resolution, light sheet illumination technology prevents samples above and below the focal plane from being excited, improving the contrast between the image and the background and the axial resolution. Currently, this technical method has been widely used in neurological research, vascular research, and developmental biology research. However, this technology is highly dependent on fluorescent labeling of biological tissues, and the imaging depth is limited by the wavelength of the excitation light. Combining the respective characteristics of photoacoustic imaging and light sheet imaging, it is necessary to integrate photoacoustic imaging and light sheet imaging so that the two imaging methods can image samples in the same system and obtain complementary information. However, both imaging technologies require the design of optical paths, and setting up independent optical paths in the same system will make the system bulky. Utility Model Content

[0004] The embodiment of the present application provides a photoacoustic and light sheet dual-modal imaging system, which is used to solve the problem in the prior art that independent optical paths are set in the same system, resulting in a large system volume.

[0005] The present application provides a photoacoustic and light sheet dual-modal imaging system, comprising:

[0006] A pulse laser source, used for generating pulse laser;

[0007] A continuous laser source, used for generating continuous laser;

[0008] A dichroic mirror is arranged downstream of the pulse laser source and the continuous laser source. The pulse laser irradiates the dichroic mirror to generate reflected pulse laser, and the continuous laser irradiates the dichroic mirror to generate transmitted continuous laser. The reflected pulse laser and the transmitted continuous laser are combined to form a laser beam.

[0009] A galvanometer mirror is disposed downstream of the dichroic mirror, and reflects the laser beam to form a scanning laser;

[0010] The scanning objective lens is arranged downstream of the galvanometer. The scanning objective lens transmits the scanning laser to form a scanning beam. The scanning beam is irradiated on the sample. The sample generates ultrasonic waves under the excitation of the reflected pulse laser, and generates fluorescence under the excitation of the transmitted continuous laser.

[0011] An ultrasonic detector is arranged between the scanning objective lens and the sample, and is used to collect ultrasonic waves to form corresponding ultrasonic signals;

[0012] A camera is arranged close to the sample and is used to collect fluorescence and form a corresponding fluorescence signal;

[0013] The computer is electrically connected to the ultrasonic detector and the camera respectively. The computer receives the ultrasonic signal and the fluorescent signal to form corresponding photoacoustic imaging images and light sheet imaging images.

[0014] In a possible implementation, the ultrasonic detector includes a mounting frame and a probe, the mounting frame is a ring structure, a plurality of probes are respectively arranged at a plurality of different positions of the mounting frame, and each probe is electrically connected to a computer.

[0015] In a possible implementation, the multiple probes are electrically connected to the first acquisition card, the first acquisition card is electrically connected to the computer, and under the control of the computer, the first acquisition card only sends the ultrasonic signal generated by one probe to the computer at the same time.

[0016] In a possible implementation, a plurality of cameras are provided, and the plurality of cameras are arranged around the sample, and each camera is electrically connected to a computer.

[0017] In a possible implementation, multiple cameras are electrically connected to a second acquisition card, the second acquisition card is electrically connected to a computer, and under the control of the computer, the second acquisition card only sends the fluorescence signal generated by one camera to the computer at the same time.

[0018] In a possible implementation, a reflector is further included, where the reflector is disposed between the dichroic mirror and the galvanometer mirror, and is used to reflect the laser beam to the galvanometer mirror.

[0019] In a possible implementation, it also includes a detection objective lens and a focusing lens, which are sequentially arranged between the sample and the camera. The fluorescence is focused by the focusing lens after being transmitted through the detection objective lens, and the focused fluorescence is received by the camera.

[0020] The photoacoustic and light sheet dual-modal imaging system in this application has the following advantages:

[0021] The pulse laser used to excite ultrasound and the continuous laser used to excite fluorescence overlap to a high degree in the optical path, thus avoiding the problem of bulky system caused by separately designed optical paths. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic structural diagram of a photoacoustic and light sheet dual-modal imaging system provided in an embodiment of the present application.

[0024] Explanation of the accompanying drawings: 100, pulsed laser source; 200, continuous laser source; 300, dichroic mirror; 310, reflecting mirror; 320, galvanometer; 330, scanning objective lens; 400, ultrasonic detector; 500, sample; 600, detection objective lens; 610, focusing lens; 700, camera. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] Figure 1 A schematic diagram of the structure of a photoacoustic and light sheet dual-modal imaging system provided in an embodiment of the present application. An embodiment of the present application provides a photoacoustic and light sheet dual-modal imaging system, comprising:

[0027] A pulse laser source 100, used to generate pulse laser;

[0028] A continuous laser source 200, used to generate continuous laser light;

[0029] A dichroic mirror 300 is disposed downstream of the pulse laser source 100 and the continuous laser source 200. The pulse laser irradiates the dichroic mirror 300 to generate a reflected pulse laser. The continuous laser irradiates the dichroic mirror 300 to generate a transmitted continuous laser. The reflected pulse laser and the transmitted continuous laser are combined to form a laser beam.

[0030] The galvanometer 320 is disposed downstream of the dichroic mirror 300, and the galvanometer 320 reflects the laser beam to form a scanning laser;

[0031] The scanning objective lens 330 is arranged downstream of the galvanometer mirror 320. The scanning objective lens 330 transmits the scanning laser to form a scanning beam. The scanning beam is irradiated on the sample 500. The sample 500 generates ultrasonic waves under the excitation of the reflected pulse laser, and generates fluorescence under the excitation of the transmitted continuous laser.

[0032] The ultrasonic detector 400 is disposed between the scanning objective lens 330 and the sample 500, and is used to collect ultrasonic waves to form corresponding ultrasonic signals;

[0033] A camera 700 is disposed near the sample 500 and is used to collect fluorescence to form a corresponding fluorescence signal;

[0034] The computer is electrically connected to the ultrasound probe 400 and the camera 700 respectively. The computer receives the ultrasound signal and the fluorescence signal to form corresponding photoacoustic imaging images and light sheet imaging images.

[0035] For example, the wavelength of the pulse laser source 100 in the embodiment of the present application is 532nm, and the wavelength of the continuous laser source 200 is 488nm. The angle between the dichroic mirror 300 and the horizontal direction is 45°, the pulse laser is emitted from the horizontal direction to the dichroic mirror 300, and the reflected pulse laser propagates downward in the vertical direction. The continuous laser is irradiated downward on the dichroic mirror 300 in the vertical direction, and the transmitted continuous laser propagates downward in the vertical direction. Therefore, the directions of the reflected pulse laser and the transmitted continuous laser are the same, and at this time, the two laser beams will be combined to form a laser beam.

[0036] In the embodiment of the present application, a reflector 310 is further included, and the reflector 310 is disposed between the dichroic mirror 300 and the galvanometer mirror 320, and the reflector 310 is used to reflect the laser beam to the galvanometer mirror 320. The reflector 310 is parallel to the dichroic mirror 300, so the laser beam propagating vertically downward will be transformed into propagating in the horizontal direction after reflection, and finally irradiated on the galvanometer mirror 320.

[0037] The galvanometer 320 in the embodiment of the present application is a resonant galvanometer. By continuously changing the direction of the galvanometer 320, the point-shaped laser beam is irradiated on different positions of the scanning objective lens 330, thereby approximately forming a linear scanning laser.

[0038] The scanning objective lens 330 in the embodiment of the present application is a convex lens, and the point where the laser beam is irradiated on the galvanometer 320 coincides with the focus of the convex lens. Therefore, the scattered scanning laser will be converted by the scanning objective lens 330 into parallel light propagating downward, and the parallel scanning beam can cover all positions of the sample 500.

[0039] The ultrasonic waves generated by the sample 500 after being excited by the reflected pulse laser will propagate in all directions, and the ultrasonic detector 400 located between the sample 500 and the scanning objective lens 330 can collect these ultrasonic waves and then convert them into ultrasonic signals in the form of electrical signals.

[0040] In the embodiment of the present application, the ultrasonic detector 400 includes a mounting frame and a probe. The mounting frame is a ring structure. A plurality of probes are respectively arranged at a plurality of different positions of the mounting frame, and each probe is electrically connected to a computer. Specifically, the cavity inside the mounting frame is used to pass the scanning beam to prevent the mounting frame from blocking the propagation of the scanning beam. The probes are evenly arranged on the surface of the mounting frame facing the sample 500 so that the probes can normally collect ultrasonic waves.

[0041] Furthermore, multiple probes are electrically connected to the first acquisition card, the first acquisition card is electrically connected to the computer, and the first acquisition card only sends the ultrasonic signal generated by one probe to the computer at the same time under the control of the computer. Specifically, the first acquisition card has multiple input interfaces and an output interface, the multiple input interfaces are connected to each probe one by one, and the output interface is connected to the computer. When the computer controls the first acquisition card, each probe will be selected in turn according to a pre-set order and time, so that the ultrasonic signal generated by the selected probe can be transmitted to the computer. It should be understood that when controlling the probe selection, the two adjacent probes should be selected continuously, that is, there is no time interval, so that the ultrasonic signal can be continuously transmitted to the computer.

[0042] In the embodiment of the present application, a plurality of cameras 700 are provided, and the plurality of cameras 700 are arranged around the sample 500, and each camera 700 is electrically connected to a computer. Specifically, unlike ultrasound, fluorescence has a strong directionality during propagation, so in order to collect fluorescence as accurately as possible, the embodiment of the present application is provided with a plurality of cameras 700, and the plurality of cameras 700 are evenly distributed around the sample 500.

[0043] Further, the plurality of cameras 700 are electrically connected to the second acquisition card, the second acquisition card is electrically connected to the computer, and the second acquisition card only sends the fluorescence signal generated by one camera 700 to the computer at the same time under the control of the computer. Similar to the first acquisition card, the second acquisition card also has a plurality of input interfaces and an output interface, wherein the plurality of input interfaces are connected to each camera 700 one by one, and the output interface is connected to the computer. When the computer controls the second acquisition card, it will select each camera 700 in turn according to a pre-set sequence and time, so that the fluorescence signal generated by the selected camera 700 can be transmitted to the computer. It should be understood that when controlling the camera 700 to be selected, the two adjacent cameras 700 should be selected continuously, that is, there is no time interval, so that the fluorescence signal can be continuously transmitted to the computer.

[0044] Furthermore, it also includes a detection objective lens 600 and a focusing lens 610, which are sequentially arranged between the sample 500 and the camera 700. After the fluorescence is transmitted through the detection objective lens 600, it is focused by the focusing lens 610, and the focused fluorescence is received by the camera 700. Specifically, the detection objective lens 600 and the focusing lens 610 are both convex lenses, and the fluorescence emitted by the sample 500 is transmitted to the detection objective lens 600 in a dispersed form. The detection objective lens 600 converts the dispersed fluorescence into parallel light, which is again converted into concentrated fluorescence by the focusing lens 610, and the concentrated fluorescence is finally received by the camera 700.

[0045] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0046] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A photoacoustic and light sheet dual-modal imaging system, characterized in that: include: A pulse laser source (100) for generating pulse laser; A continuous laser source (200), used to generate continuous laser light; A dichroic mirror (300) is arranged downstream of the pulse laser source (100) and the continuous laser source (200), the pulse laser irradiating the dichroic mirror (300) generates reflected pulse laser, the continuous laser irradiating the dichroic mirror (300) generates transmitted continuous laser, and the reflected pulse laser and the transmitted continuous laser are combined to form a laser beam; A galvanometer (320) is arranged downstream of the dichroic mirror (300), and the galvanometer (320) reflects the laser beam to form a scanning laser; A scanning objective lens (330) is arranged downstream of the galvanometer (320), wherein the scanning objective lens (330) transmits the scanning laser to form a scanning beam, wherein the scanning beam is irradiated on the sample (500), and the sample (500) generates ultrasonic waves under the excitation of the reflected pulse laser, and the sample (500) generates fluorescence under the excitation of the transmitted continuous laser; An ultrasonic detector (400) is arranged between the scanning objective lens (330) and the sample (500), and the ultrasonic detector (400) is used to collect the ultrasonic wave and form a corresponding ultrasonic signal; A camera (700) is arranged at a position close to the sample (500), and the camera (700) is used to collect the fluorescence to form a corresponding fluorescence signal; A computer is electrically connected to the ultrasound probe (400) and the camera (700) respectively, and the computer receives the ultrasound signal and the fluorescence signal to form corresponding photoacoustic imaging images and light sheet imaging images.

2. The photoacoustic and light sheet dual-modal imaging system according to claim 1, characterized in that: The ultrasonic detector (400) comprises a mounting frame and a probe, the mounting frame is a ring structure, a plurality of the probes are respectively arranged at a plurality of different positions of the mounting frame, and each of the probes is electrically connected to the computer.

3. The photoacoustic and light sheet dual-modal imaging system according to claim 2, characterized in that: The plurality of probes are all electrically connected to a first acquisition card, the first acquisition card is electrically connected to the computer, and under the control of the computer, the first acquisition card simultaneously sends the ultrasonic signal generated by only one of the probes to the computer.

4. The photoacoustic and light sheet dual-modal imaging system according to claim 1, characterized in that: A plurality of cameras (700) are provided, and the plurality of cameras (700) are arranged around the sample (500), and each of the cameras (700) is electrically connected to the computer.

5. The photoacoustic and light sheet dual-modal imaging system according to claim 4, characterized in that: The plurality of cameras (700) are all electrically connected to a second acquisition card, the second acquisition card is electrically connected to the computer, and the second acquisition card, under the control of the computer, simultaneously sends the fluorescence signal generated by only one camera (700) to the computer.

6. The photoacoustic and light sheet dual-modal imaging system according to claim 1, characterized in that: It also includes a reflecting mirror (310), wherein the reflecting mirror (310) is arranged between the dichroic mirror (300) and the galvanometer mirror (320), and the reflecting mirror (310) is used to reflect the laser beam to the galvanometer mirror (320).

7. The photoacoustic and light sheet dual-modal imaging system according to claim 1, characterized in that: It also includes a detection objective lens (600) and a focusing lens (610), wherein the detection objective lens (600) and the focusing lens (610) are sequentially arranged between the sample (500) and the camera (700), and the fluorescence is focused by the focusing lens (610) after being transmitted through the detection objective lens (600), and the focused fluorescence is received by the camera (700).

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