High-speed scanning photoacoustic image input device and control method thereof

Abstract

The present application relates to a kind of high-speed scanning photoacoustic image input device and method thereof, make photoacoustic microscope high-speed scanning simultaneously, receive the input of ultrasonic wave signal and convert into three-dimensional image, so high-resolution three-dimensional image about detection object body can be generated at high speed.The high-speed scanning photoacoustic image input device of the present application, comprising: photoacoustic transceiver, by laser generation part towards detection object body output laser pulse output, receive the ultrasonic wave image signal emitted from detection object body;Analog-digital conversion unit, receive the input of ultrasonic wave image signal, and convert into digital image signal;Main control unit, receive the input of digital image signal, generate the ultrasonic wave scanning three-dimensional image information about detection object body;Trigger control unit, receive the input of photoacoustic probe motion information, generate the scanning trigger corresponding to motion information, and main control unit is sequentially synthesized with the image corresponding to ultrasonic wave image signal according to scan line unit, generate the image about detection object body.

Description

Technical Field

[0001] This invention relates to a high-speed scanning photoacoustic image input device and its control method, and more specifically to a high-speed scanning photoacoustic image input device and its control method, wherein the high-speed scanning photoacoustic image input device can generate a two-dimensional or three-dimensional image of the object being detected (the subject) while moving the photoacoustic probe at high speed. Background Technology

[0002] If a high-energy light is shone on an object, the object absorbs the light energy and undergoes thermoelastic expansion. This elastic expansion generates pressure waves, which exhibit ultrasonic wave characteristics. This phenomenon is called the "photoacoustic effect," and the ultrasonic signals generated by this expansion are called photoacoustic signals.

[0003] The technology of using photoacoustic effects to acquire information about the internal state of an object, especially its interior, and generating images from this information has recently attracted attention, particularly in the medical field, where much research has been conducted. In the medical treatment of diseases, there are situations where it is necessary to visually confirm the internal state of a living organism. Currently, widely used tools for generating images of the internal state of organisms include well-known methods such as X-rays, CT scans, and MRI. However, reports indicate that these methods are accompanied by many problems: expensive equipment, very low resolution of the generated images, narrow field of view, long processing times, and potential health risks due to prolonged use. Therefore, the use of photoacoustic effects to generate images of the internal state of organisms (photoacoustic imaging) has attracted considerable attention as an alternative to these methods.

[0004] However, in order to effectively utilize the technology of generating images from the internal state information of organisms during medical treatment, enabling high-speed scanning and reducing the time required for image processing, it is necessary to acquire the internal state information of organisms in real time. Furthermore, this requires ensuring a high signal-to-noise ratio (SNR) and a wide field of view (FOV) to generate high-resolution images. Summary of the Invention

[0005] The purpose of this invention is to provide a high-speed scanning photoacoustic image input device and method, which enables a photoacoustic microscope to receive ultrasonic signal input while performing high-speed scanning, thereby converting it into a two-dimensional or three-dimensional image. Therefore, it can generate high-resolution two-dimensional or three-dimensional images of the object being tested at high speed.

[0006] According to an embodiment of the present invention, a high-speed scanning photoacoustic image input device converts the unidirectional rotational motion of a drive motor into the linear reciprocating motion of a photoacoustic probe connected to the drive motor, and uses the linear motion of the photoacoustic probe and the vertical motion perpendicular to the linear motion to perform a two-dimensional scan of the object to be detected, thereby generating a three-dimensional image of the object to be detected (the subject). The device includes: photoacoustic transceivers 10 and 20, which output laser pulses toward the object to be detected via a laser generator 10, thereby receiving ultrasonic image signals emitted from the object to be detected; an analog-to-digital converter 30, which receives the input ultrasonic image signals and converts them into digital image signals; and a main control unit 40. The main control unit 40 receives input digital image signals and generates ultrasonic scanning three-dimensional image information about the object being detected. The trigger control unit 50 receives input motion information (encoder pulse signal) from the photoacoustic probe and generates a scan trigger corresponding to the motion information. It also receives input laser pulse output information (laser sensing signal) and generates a laser trigger corresponding to the laser pulse output. The main control unit 40 generates an output trigger signal corresponding to the laser trigger and outputs it to the analog-to-digital converter 30. The main control unit 40 can sequentially synthesize images corresponding to the ultrasonic image signals according to scan line units, thereby generating an image about the object being detected. The ultrasonic image signals correspond to the output trigger signals.

[0007] The analog-to-digital converter 30 can convert the ultrasonic image signal (A-scan signal) corresponding to the output trigger from the ultrasonic image signal input from the ultrasonic receiver 20 of the photoacoustic transceiver units 10 and 20 into a digital image signal and transmit it to the main control unit 40.

[0008] The main control unit 40 can synthesize the input digital image signals sequentially according to the scan line unit and generate a line image (B scan signal), and synthesize the line images of each scan line to generate a three-dimensional image (C scan signal).

[0009] Each even-numbered line image is synthesized in reverse order to generate a line image, which is then combined with the odd-numbered images to generate a three-dimensional image (C-scan signal).

[0010] The unidirectional rotational motion of the drive motor can be converted into the linear parallel motion of the photoacoustic probe by means of the slider-crank mechanism. A pair of photoacoustic probes can be set on the slider in a way that is spaced apart from each other in the same direction as the extension of the track. A pair of photoacoustic probes can be set at the same distance from the slider, with the distance being twice the rotation radius of the crank shaft.

[0011] The unidirectional rotational motion of the drive motor can be converted into the linear parallel motion of the photoacoustic probe by means of the slider-crank mechanism. A pair of photoacoustic probes can be set on the slider in the same direction as the extension of the track, spaced apart from each other. A pair of photoacoustic probes can be set at the same distance from the slider, spaced apart by a distance smaller than twice the rotation radius of the crankshaft.

[0012] The high-speed scanning photoacoustic image input device may include: a laser generating unit 10 that generates a laser beam; a beam splitter that branches the laser beam into a first laser beam and a fourth laser beam; a photodetector PD that generates a laser sensing signal (pulse signal) by sensing the fourth laser beam; a junction that reflects the first laser beam and illuminates the object being detected, and allows an ultrasonic signal generated on the object to pass through; and an ultrasonic receiving unit 20 that receives the ultrasonic image signal passing through the junction.

[0013] A high-speed scanning photoacoustic image input device may include: a laser generating unit 10 that generates a laser beam; a first beam splitter VBS1 that branches the laser beam into a first laser beam and a second laser beam; a second beam splitter VBS2 that branches the second laser beam into a third laser beam and a fourth laser beam; a photodetector PD that generates a laser sensing signal (pulse signal) by sensing the fourth laser beam; a first junction OAC1 that reflects and irradiates a portion of the object being detected by the first laser beam, allowing an ultrasonic signal generated on the object to pass through; a second junction OAC2 that reflects and irradiates a portion of the third laser beam that is spaced apart from the portion of the object being detected, allowing an ultrasonic signal generated on the object to pass through; and an ultrasonic receiving unit 20 that receives the ultrasonic image signal passing through the junctions OAC1 and OAC2.

[0014] The joint includes a mating surface that engages with two prisms. The mating surface is coated with aluminum material, which allows the irradiated laser beam to be reflected and the ultrasonic signal to pass through.

[0015] The image generation unit of the main control unit can calculate the position of the photoacoustic probe corresponding to the output trigger signal, and store the ultrasonic image signal of the calculated position in a form corresponding to each output trigger signal.

[0016] The motion information of the photoacoustic probe is the rotational motion information of the rotary encoder that detects the rotational motion of the drive motor. The rotary encoder can be an incremental rotary encoder that outputs A-phase signal, B-phase signal, and Z-phase signal.

[0017] Scan triggers can be generated based on rotational position information, which is determined by the A-phase signal of an incremental rotary encoder that detects the rotational motion of the drive motor. The linear motion position of the photoacoustic probe when generating each output trigger signal can be calculated, and the ultrasonic image signal of the calculated linear motion position can be stored in a form corresponding to each output trigger signal.

[0018] A scan trigger can be generated based on the linear motion position of the probe. The linear motion position of the probe is calculated by a linear encoder pulse signal generated by a linear encoder that detects the linear motion of the photoacoustic probe, and the ultrasonic signal of the linear motion position of each probe is stored in a form corresponding to each output trigger signal.

[0019] The motion information of the photoacoustic probe can include the rotational motion information of the rotary encoder that detects the rotational motion of the drive motor and the linear motion information of the linear encoder that detects the linear motion of the photoacoustic probe. The rotary encoder is an incremental rotary encoder that outputs A-phase signals, B-phase signals and Z-phase signals in pulse form respectively. The linear encoder outputs linear pulse signals at certain intervals according to the position on the linear motion trajectory of the probe.

[0020] The drive motor begins unidirectional rotation. After the Z-phase signal of the rotary encoder is generated, the A-phase signal with a preset number of pulses Z1 is input. The trigger control unit generates a first trigger event. If the first trigger event is generated, the pulse signal of the linear encoder can be used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

[0021] Scan triggers can be generated at intervals that are integer multiples of the pulse signal intervals of the linear encoder.

[0022] After stopping the generation of scan triggers, the trigger control unit generates a second trigger event signal in a manner corresponding to the position of the preset photoacoustic probe. If a second trigger event is generated, the pulse signal of the linear encoder can be used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

[0023] A high-speed scanning photoacoustic image input device may include: an object region input unit that receives an input image of an object region including a detected object; and a scanning region extraction unit that extracts a scanning region from the image of the object region, which is determined by the position values ​​of the start and end points of the region belonging to the area where the photoacoustic image of the detected object is acquired.

[0024] A control method for a high-speed scanning photoacoustic image input device according to an embodiment of the present invention can acquire photoacoustic images through the high-speed scanning photoacoustic image input device.

[0025] According to the present invention, while enabling the photoacoustic microscope to perform high-speed scanning, the input of photoacoustic signals is received in real time and converted into a three-dimensional image, thereby generating high-resolution three-dimensional image information about the object being tested at high speed.

[0026] Furthermore, by utilizing a slider-crank mechanism to acquire photoacoustic image signals of the object being detected, high-speed scanning of the object can be achieved.

[0027] In addition, it includes a dual-channel photoacoustic probe, which expands the field of view (FOV), enabling rapid image acquisition over a large detection area, including the object being detected.

[0028] Furthermore, when using a slider-crank mechanism, after inputting the actual reference point pulse signal of the encoder, the pulse signal input after inputting the set number of pulse signals is used as a virtual reference point pulse signal. This prevents problems that may occur due to the inability to stably represent the actual reference point pulse signal, and generates an accurate image of the object being detected.

[0029] In other words, the start of the scanning action using the actual reference point pulse signal (e.g., the Z-phase pulse signal) and the start of the photoacoustic signal acquisition (image information acquisition) using the virtual reference point pulse signal are separated by a certain time, thus noise can be removed, thereby obtaining accurate and high-resolution image information.

[0030] In addition, a scanning trigger signal is generated according to the set encoder pulse signal interval, thereby generating an output trigger signal. The ultrasonic image signal input with the output trigger signal is converted into an image signal of the object, so that the set position information and the image information based on the corresponding position information can be accurately matched, and accurate image information about the object can be generated at high speed. Attached Figure Description

[0031] Figure 1 This is a schematic block diagram illustrating a high-speed scanning photoacoustic image input device according to an embodiment of the present invention.

[0032] Figure 2 More specific manifestation Figure 1 The figure shows a schematic representation of an embodiment of a high-speed scanning photoacoustic image input device.

[0033] Figure 3 It is shown in general terms. Figure 2 The diagram shows the linear reciprocating motion drive unit of the dual-channel photoacoustic probe in a high-speed scanning photoacoustic image input device.

[0034] Figure 4 It is shown in general terms. Figure 3A diagram of the slider-crank mechanism of the linear reciprocating motion drive unit of the photoacoustic probe.

[0035] Figure 5 It is shown in general terms. Figure 1 Timing diagram of the method for generating output trigger signals in a high-speed scanning photoacoustic image input device.

[0036] Figure 6 It is shown in general terms. Figure 1 The diagram shows the process of scanning the object being inspected using a slider-crank mechanism in a high-speed scanning photoacoustic image input device.

[0037] Figure 7 This is a schematic block diagram illustrating a high-speed scanning photoacoustic image input device according to another embodiment of the present invention.

[0038] Figure 8 This is a schematic block diagram illustrating a high-speed scanning photoacoustic image input device according to another embodiment of the present invention. Detailed Implementation

[0039] Hereinafter, based on preferred embodiments of the present invention, the specific content for implementing the present invention will be described in detail with reference to the accompanying drawings. At this time, constituent elements that appear in the drawings of one embodiment and are identical to those appearing in the drawings of other embodiments are given the same reference numerals, and the descriptions in other embodiments are equally applicable; detailed descriptions of these elements may be omitted. Furthermore, well-known functions or components related to the present invention refer to well-known technologies, and detailed descriptions of these aspects are simplified or omitted here.

[0040] Furthermore, regarding the terminology used in this specification, widely used and common terms have been employed to the extent possible while considering the functionality of the invention. However, this may vary depending on the intent of those skilled in the art, precedents, or the emergence of new technologies. In addition, in specific cases, the inventor may arbitrarily choose terms, the meaning of which will be detailed in the description of the invention in such cases. Therefore, the terms used in this specification should be defined based on their meanings and the overall content of the invention, rather than simply their names.

[0041] When a part is referred to as "comprising" a certain constituent element throughout this specification, it means that, unless specifically stated to the contrary, other constituent elements are not excluded, but may be included. Furthermore, the term "part" as used in this specification means not only hardware components such as FPGAs or ASICs, but also software components. However, "part" is not limited to the meaning of software or hardware. A "part" can be configured in the form of being disposed on an addressable storage medium, or in a form that causes one or more processors to play. Thus, as an example, a "part" includes constituent elements such as software constituent elements, object-oriented software constituent elements, category constituent elements, and task constituent elements, steps, functions, attributes, programs, subroutines, segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided in constituent elements and "parts" can be combined from smaller constituent elements and "parts," or can be separated into additional constituent elements and "parts."

[0042] The method for generating photoacoustic images of an object, particularly the interior of a living organism, using the photoacoustic effect is as follows. First, a light beam (e.g., a laser beam) is irradiated onto a specific part of the living organism from which a three-dimensional image is to be acquired. A photoacoustic signal (ultrasonic signal) generated by thermoelastic expansion is acquired using an ultrasonic probe (ultrasonic transducer). By performing prescribed signal processing on the acquired photoacoustic signal, image information about the interior of the living organism is generated, wherein thermoelastic expansion is generated at that specific part due to the irradiated light beam.

[0043] A high-speed scanning photoacoustic image input device according to an embodiment of the present invention may include a photoacoustic microscope (PAM). Furthermore, the photoacoustic probe of the photoacoustic microscope (PAM) can scan an object region, including the object to be inspected, while moving at high speed using a slider-crank mechanism. The high-speed scanning photoacoustic image input device can convert the unidirectional rotational motion of a drive motor into the linear reciprocating motion of the photoacoustic probe connected to the drive motor. Furthermore, the object to be inspected can be scanned in two dimensions by the linear motion of the photoacoustic probe and the vertical motion perpendicular to the linear motion, thereby generating a three-dimensional image of the object to be inspected (the subject).

[0044] The photoacoustic microscope (PAM) of the present invention can use an optical-resolution photoacoustic microscope (OR-PAM) that focuses a light beam (e.g., a laser beam) and has a spatial resolution on the order of micrometers. The optical-resolution photoacoustic microscope (OR-PAM) can utilize a more compact optical focal length.

[0045] Furthermore, acoustic-resolution photoacoustic microscopy (AR-PAM) utilizes a more compact acoustic focal length. Optical-resolution photoacoustic microscopy (OR-PAM) relies on a more compact beam than the acoustic beam, thus offering the advantage of obtaining higher resolution images compared to AR-PAM. Moreover, due to its rich optical absorption contrast, it serves as a powerful imaging device in many fields, including much of medicine such as biology, dermatology, neurology, oncology, ophthalmology, and pathology.

[0046] To achieve maximum signal-to-noise ratio and optimized spatial resolution, optical resolution photoacoustic microscopy (OR-PAM) can utilize co-focal structures with both the optical excitation beam and the acoustic detection beam in a coaxial configuration. Volumetric imaging is achieved through point-by-point raster scanning of the typical beam and acoustic beam, for which a stepping motor scanning stage can be employed.

[0047] Due to the scanning step size required for lateral resolution at the micrometer level, optical resolution photoacoustic microscopy (OR-PAM) can have relatively low scanning speeds (and thus imaging speeds) and scanning ranges (approximately 1 Hz B-mode scan rate within a 1 mm scanning range). Because of this low imaging speed, it is difficult to obtain dynamic information about transient drug responses and tissue structures such as skin vascular structures using OR-PAM.

[0048] In addition, there are various methods to increase the field of view of optical resolution photoacoustic microscopy (OR-PAM), increase the scanning speed or shorten the scanning time, and maintain a high signal-to-noise ratio (SNR). However, to achieve optical resolution photoacoustic microscopy (OR-PAM), a trade-off between these three characteristics is required. This trade-off addresses the factors that make it difficult to achieve optical resolution photoacoustic microscopy (OR-PAM) that satisfy all three characteristics simultaneously. This is because the scanning time depends on the pulse repetition rate of the laser and the scanning mechanism, and is also limited by the speed of sound of photoacoustic waves within the tissue.

[0049] To reduce scanning time (increase scanning speed) in optical resolution photoacoustic microscopy (OR-PAM), various solutions can be used, such as galvanometer scanners, microelectromechanical systems (MEMS) scanners, hexagonal mirror scanners, and voice coil scanners. While these techniques have their own advantages, their limitation is that they cannot provide the maximum or optimal scanning speed.

[0050] A high-speed scanning photoacoustic image input device according to one embodiment of the present invention may include a high-speed optical resolution photoacoustic microscope (OR-PAM) utilizing a dual-channel slider-crank mechanism. In this case, dual channels can be used to double the field of view.

[0051] Figure 1 A block diagram of a high-speed scanning photoacoustic image input device 1 according to an embodiment of the present invention is shown. Figure 2 More specifically reflected Figure 1 The high-speed scanning photoacoustic image input device 1 shows an embodiment of a dual-channel high-speed scanning photoacoustic image input device.

[0052] Referring to the accompanying drawings, the high-speed scanning photoacoustic image input device 1 can convert the unidirectional rotational motion of the drive motor into, for example, the motion of the photoacoustic probe 15 connected to the drive motor. Figure 6 The linear reciprocating motion in the +X and -X directions, aided by the linear motion of the photoacoustic probe 15 and, for example, a motion perpendicular to the linear motion. Figure 6 The object is scanned in two dimensions by moving in the Y direction, which is the vertical direction, thereby generating a three-dimensional image of the object (the subject).

[0053] The high-speed scanning photoacoustic image input device 1 may include photoacoustic transceivers 10 and 20, an analog-to-digital converter 30, a main control unit 40, and a trigger control unit 50.

[0054] The photoacoustic transceivers 10 and 20 output power to the object being detected via the photoacoustic probe 15 through the laser pulse generated by the laser generator 10, thereby receiving the input ultrasonic image signal from the object being detected via the ultrasonic probe 21. The photoacoustic transceivers 10 and 20 may include the photoacoustic probe 15, and may include the laser generator 10 for generating a laser beam, the laser beam converter 11 for splitting and converting the path of the laser beam, the ultrasonic probe 21 for receiving the input ultrasonic signal, and the ultrasonic receiver 20 for receiving the input ultrasonic signal. In this case, the ultrasonic receiver 20 may include... Figure 2 The amplifier AMP shown may also include an ultrasonic probe 21 and an amplifier AMP, depending on the viewpoint.

[0055] The analog-to-digital converter 30 can receive the input of ultrasonic image signals and convert them into digital image signals. The main control unit 40 may include an image information generation unit, which receives the input of digital image signals and generates ultrasonic scanning three-dimensional image information about the object being detected. The main control unit 40 can display the three-dimensional image information on a display, or communicate with internal and / or external systems and input and / or output various signals, and can control various components included in the high-speed scanning photoacoustic image input device 1.

[0056] The trigger control unit 50 can receive motion information (encoder pulse signal) input from the photoacoustic probe 15 and generate a scan trigger corresponding to the motion information; receive laser pulse output information (laser sensing signal) input and generate a laser trigger corresponding to the laser pulse output; generate an output trigger signal corresponding to the laser trigger and output it to the analog-to-digital converter 30.

[0057] At this time, the main control unit 40 can sequentially synthesize the images corresponding to the ultrasonic image signals according to the scan line units and generate an image of the object being detected, wherein the ultrasonic image signals correspond to the output trigger signals.

[0058] In other words, in order to capture photoacoustic images using laser pulse output and ultrasonic image signals, the high-speed scanning photoacoustic image input device 1 includes basic photoacoustic transceivers 10 and 20, an analog-to-digital converter 30, and a main control unit 40. It may also include a trigger control unit 50, independent of these components. Thus, by using a simple structure and control to perform two-dimensional scanning of the target area, an image of the target object can be obtained almost in real time, providing a wide field of view and enabling ultra-high-speed generation of three-dimensional ultrasonic images.

[0059] The analog-to-digital converter 30 converts the ultrasonic image signal (A-scan image) corresponding to the output trigger from the ultrasonic receiver 20 of the photoacoustic transceiver units 10 and 20 into a digital image signal and transmits it to the main control unit 40. Furthermore, the main control unit 40 can sequentially synthesize the input digital image signals in scan line units to generate a line image (B-scan image), and synthesize the line images of each scan line to generate a three-dimensional image (C-scan image). Each even-numbered line image is synthesized in reverse order to generate a line image, which is then synthesized with the odd-numbered images to generate a three-dimensional image (C-scan image).

[0060] At this time, the trigger control unit 50 receives the laser sensing signal and the rotary and / or linear encoder pulse signal input from the photoacoustic transceiver units 10 and 20, and generates a scan trigger signal and a laser trigger signal respectively. It then generates an output trigger signal synchronized with the laser trigger signal following the scan trigger signal and outputs it. The analog-to-digital converter 30 receives the output trigger signal input from the trigger control unit 50, converts the ultrasonic image signal (A-scan signal) corresponding to the output trigger signal from the ultrasonic image signal input from the ultrasonic receiver of the photoacoustic transceiver units 10 and 20 into a digital image signal, and transmits it to the image generation unit. The image generation unit sequentially synthesizes the input digital image signals according to scan line units and generates a line image (B-scan signal). It then synthesizes the line images of each scan line and generates a three-dimensional image (C-scan signal).

[0061] At this point, the even-numbered line images can be synthesized in reverse order to generate a line image, which is then combined with the odd-numbered images to generate a three-dimensional image (C-scan signal). In this case, one rotation of the drive motor is converted into a linear reciprocating motion of the photoacoustic probe 15, thus covering two scan lines with one motor rotation, resulting in a faster scanning speed. Furthermore, in this configuration, the even-numbered and odd-numbered line images can be synthesized in reverse order to generate an accurate three-dimensional image (C-scan signal).

[0062] Therefore, in this invention, a slider-crank mechanism can be used to perform high-speed scanning of the object being detected with a wide field of view, and the high-speed scanned images can be accurately synthesized.

[0063] Therefore, a high-speed scanning photoacoustic image input device 1 according to an embodiment of the present invention may include a laser generating unit 10, a beam splitter VBS, a photodetector PD, a coupling unit OAC, and an ultrasonic receiving unit UT. The laser generating unit 10 generates a laser beam. The beam splitter VBS branches the laser beam into a first laser beam and a fourth laser beam. In this case, the beam splitter VBS may be a variable beam splitter capable of adjusting the amount and / or size of each of the branched laser beams.

[0064] The optical detector (PD) senses the fourth laser beam and generates a pulse signal from the laser sensing signal. The coupling (OAC) reflects the first laser beam and illuminates the object being detected. To allow the ultrasonic signal generated on the object to pass through, optical and acoustic signals are combined. The ultrasonic receiver (UT) receives the ultrasonic image signal passing through the coupling (OAC).

[0065] This embodiment relates to a single-channel high-speed scanning photoacoustic image input device including a photoacoustic probe 15. Most of the laser beam output from a laser generator 10 can be transmitted to the photoacoustic probe 15 via a beam splitter (VBS), while a relatively small portion of the laser beam is transmitted to the photodetector (PD). At this time, referring to... Figure 2 and Figure 5 The photodetector PD can sense the laser beam transmitted to the photoacoustic probe 15 and transmit the laser sensing signal to the trigger control unit 50. At this time, the trigger control unit 50 can generate a scan trigger from the pulse signal of the rotary and / or linear encoder, generate a laser trigger in a form corresponding to the laser sensing signal after the scan trigger, and generate an output trigger synchronized with it. After generating the output trigger signal synchronized with the output trigger, it can be transmitted to the analog-to-digital converter 30.

[0066] Therefore, the analog-to-digital converter 30 receives the input of the output trigger signal and the ultrasonic image signal, and stores the ultrasonic image signal corresponding to the output trigger signal as an ultrasonic image signal corresponding to the sequentially specified positions of the rotary and / or linear encoders. This allows for the synthesis of accurate images corresponding to the object being detected, unit by unit of scan lines. In other words, ultrasonic image signals corresponding to the sequentially specified positions of the rotary and / or linear encoders can be obtained.

[0067] Therefore, the image generation unit of the main control unit 40 can calculate the position of the photoacoustic probe 15 corresponding to the output trigger signal, and store the ultrasonic image signal of the calculated position in a form corresponding to each output trigger signal.

[0068] As another embodiment of the present invention, such as Figure 2 The high-speed scanning photoacoustic image input device 1 shown may include a laser generator 10, a first beam splitter VBS1, a second beam splitter VBS2, a photodetector PD, a first junction OAC1, a second junction OAC2, and an ultrasonic receiver UT. This embodiment relates to a dual-channel high-speed scanning photoacoustic image input device including two photoacoustic probes 15, which can substantially double the field of view (FOV).

[0069] In other words, the laser beam output from a laser generator 10 is split into two main laser beams and one signal laser beam by beam splitters VBS1 and VBS2. The majority of the beam is formed into two main laser beams, which are transmitted to the photoacoustic probe 15 via the first junction OAC1 and the second junction OAC2, respectively. Additionally, a relatively small portion of the signal laser beam can be transmitted to the photodetector PD.

[0070] The laser generating unit 10 generates a laser beam. A first beam splitter VBS1 branches the laser beam into a first laser beam and a second laser beam. A second beam splitter VBS2 branches the second laser beam into a third laser beam and a fourth laser beam. In this case, the beam splitter VBS can be a variable beam splitter capable of adjusting the amount and / or size of each branched laser beam.

[0071] The optical detector (PD) can sense the fourth laser beam and generate the laser sensing signal as a pulse signal.

[0072] The first junction OAC1 reflects and illuminates the first laser beam onto the object being detected. To allow the ultrasonic signal generated on the object to pass through, optical and acoustic signals can be combined. The second junction OAC2 reflects and illuminates a portion of the object being detected. To allow the ultrasonic signal generated on the object to pass through, optical and acoustic signals can be combined. At this point, the third laser beam is reflected and illuminates another portion of the object separated from it by a certain distance, illuminating an area different from the first laser beam on the object, thereby obtaining image signals from other areas.

[0073] The ultrasonic receiver UT can receive ultrasonic image signals from positions that are separated from each object being detected by various joints OAC1 and OAC2.

[0074] In this case, the photodetector PD can sense the laser beam transmitted to the photoacoustic probe 15 and transmit the laser sensing signal to the trigger control unit 50. At this time, the trigger control unit 50 generates a scan trigger from the pulse signal of the rotary and / or linear encoder, and generates a laser trigger in a form corresponding to the laser sensing signal after the scan trigger, thereby generating an output trigger synchronized with it. After generating the output trigger signal synchronized with the output trigger, it can be transmitted to the analog-to-digital converter 30.

[0075] Therefore, the analog-to-digital converter 30 receives the output trigger signal and the ultrasonic image signal, and stores the ultrasonic image signal corresponding to the output trigger signal as an ultrasonic image signal corresponding to the sequentially specified positions of the rotary and / or linear encoders, thereby enabling the synthesis of accurate images corresponding to the object being detected on a per-scan-line basis. In other words, ultrasonic image signals corresponding to the sequentially specified positions of the rotary and / or linear encoders can be obtained.

[0076] Therefore, the image generation unit of the main control unit 40 can calculate the position of the photoacoustic probe 15 corresponding to the output trigger signal and store the ultrasonic image signal of the calculated position in a form corresponding to each output trigger signal.

[0077] At this time, the position corresponding to the position of a rotary and / or linear encoder can be two positions spaced apart between a pair of photoacoustic probes 15, which can correspond to a pair of input ultrasonic image signals respectively.

[0078] The first beam splitter VBS1 receives the laser beam generated by the laser generating unit 10 and branches it into a first laser beam and a second laser beam VBS2. The laser beam generated by the laser generating unit 10 can be transmitted to the first beam splitter VBS1 from the laser generating unit 10 via free space, through a lens or mirror, or via optical fiber. The generated laser beam is pulsed, and the pulse repetition rate can be adjusted.

[0079] The first and third laser beams can be transmitted to the photoacoustic probe 20 and output to the object being detected, respectively. Thus, the ultrasonic signal returning from the object being detected can be input to the analog-to-digital converter 30 via the photoacoustic probe 20. In this case, the photoacoustic probe 15 may also include coupling portions OAC1 and OAC2 and the ultrasonic probe UT. The coupling portions OAC1 and OAC2 combine the optical signal of the laser beam output towards the object being detected and the acoustic signal of the ultrasonic signal returning from the object being detected. In other words, the coupling portions OAC1 and OAC2 combine the optical and acoustic signals in a manner that allows them to partially overlap and pass through a single component.

[0080] The joints OAC1 and OAC2 reflect the laser beam and direct it onto the object. Focusing can be achieved using a convex lens, but for more accurate focusing, an aspherical lens can be used. The ultrasonic signal generated by the thermoelastic expansion of the object due to the laser beam reflected from the joints OAC1 and OAC2 passes through them, and the ultrasonic receiver UT receives the ultrasonic signal passing through the joints 105. Furthermore, the joints OAC1 and OAC2 include a mating surface that engages with two prisms; this surface is coated with aluminum, which reflects the irradiated laser beam, allowing the ultrasonic signal to pass through.

[0081] In addition, in order to improve the performance of receiving ultrasonic waves by means of ultrasonic receiving unit UT, ultrasonic signals through the joints OAC1 and OAC2 can be received to ultrasonic receiving unit UT through acoustic lenses. Ultrasonic receiving unit UT can make the received ultrasonic signals located in the vertical direction of the XY plane where the object is located in a spaced manner, and is equipped with an ultrasonic probe that moves in a zigzag pattern along the XY direction.

[0082] Image information about the object can be generated by scanning the detection area, including the object being detected. At this time, the rotational motion of the drive motor can be converted into the linear reciprocating motion of the photoacoustic probe 15 by means of a slider-crank mechanism.

[0083] Figure 3 Briefly show Figure 2 The linear reciprocating motion drive unit of the dual-channel photoacoustic probe of the high-speed scanning photoacoustic image input device 1. Figure 4Briefly show Figure 3 The linear reciprocating motion drive unit of the photoacoustic probe uses a slider-crank mechanism.

[0084] Referring to the accompanying drawings, the high-speed scanning photoacoustic image input device 1 enables the unidirectional rotational motion of the drive motor to be converted into the linear parallel motion of the photoacoustic probe 160 via a slider-crank mechanism. For this purpose, a pair of photoacoustic probes 160 are positioned on the slider 150 in a direction parallel to the extension of the track 140, spaced apart from each other. The pair of photoacoustic probes 160 can be positioned with the slider 150 as a reference, at the same distance R, spaced apart by twice the crankshaft rotation radius R (2R).

[0085] At this time, a pair of photoacoustic probes 160 are set at the same distance from the slider 150, in a form that is twice the rotation radius R of the crankshaft 120, so that the maximum field of view (FOV) can be achieved when no part of the object is missed, including two or more photoacoustic probes 160.

[0086] As another embodiment, a pair of photoacoustic probes 160 can be arranged with the slider 150 as a reference at the same distance R, but spaced apart by a distance smaller than twice the crankshaft rotation radius R, 2R.

[0087] At this point, a pair of photoacoustic probes 160 can be positioned with the slider 150 at the same distance, spaced apart by a distance smaller than 2R, which is twice the rotation radius R of the crankshaft 120. In this configuration, an overlap between the pair of photoacoustic probes 160 may occur, thereby stably expanding the field of view (FOV) while ensuring no part of the object is missed. This is particularly useful when the scan trigger is generated at intervals that are two or more integer multiples of the linear encoder pulse signal.

[0088] The slider-crank mechanism 100 may include a drive shaft 110, a crankshaft 120, a connecting rod 130, a track 140, a slider 150, and a photoacoustic probe 160. In this case, the drive shaft 110 may serve as the rotating shaft of a motor or be an extension connected to the rotating shaft of the motor. The crankshaft 120 may be fixedly mounted on the drive shaft and rotate, with one end connected to the connecting rod 130 via a rotary joint.

[0089] Furthermore, the track 140 can be fixedly mounted on the frame, and the slider 150 can be mounted on the track 140 in a linear motion manner via a linear guide or the like. In this case, the slider 150 can be connected via a rotary joint to the opposite end of the connection between the slider 150 and the crankshaft 120 of the connecting rod 130. A photoacoustic probe 160 can be mounted at the end of the slider 150.

[0090] Thus, the rotation of the crankshaft 120 can be generated by the rotation of the drive shaft 110, and the linear motion of the photoacoustic probe 160 fixed to the slider 150 can be generated by the rotation of the crankshaft 120.

[0091] Additionally, a balance block 105 can be connected to the other end of the crankshaft 120. This allows for stable rotation of the crankshaft 120, and when the photoacoustic probe 160 is in high-speed parallel motion, stable parallel motion can be achieved by reducing vibration.

[0092] Figure 4 The center point O can be called a fixed link, and point B can be called a sliding link. From a mechanical perspective, the fixed link is equivalent to a drive motor that performs rotary motion, and the sliding link is equivalent to a scanning probe that performs linear reciprocating motion. Figure 4 In this context, OC refers to the crank-connecting rod, and CB refers to the coupling rod. From a mechanical perspective, the crank-connecting rod is equivalent to the crankshaft, while the coupling rod can be considered a connecting rod.

[0093] One end of the crankshaft is securely connected to the motor's main shaft, while the other end is connected to one end of the connecting rod in a manner similar to a hinge. The other end of the connecting rod is also connected to the probe in a similar manner. When the motor rotates, the crankshaft rotates in the same direction as the motor's rotation. This rotation pushes one end of the connecting rod, and this force is transmitted along the length of the connecting rod to the other end, thus inducing the probe's linear reciprocating motion (movement in the +X and -X directions). This mechanism is similar to the crankshaft and piston movement mechanism of a four-stroke engine, a type of internal combustion engine. Furthermore, to ensure the stability of the linear reciprocating motion, a linear guide is typically installed on the sliding rod (probe side).

[0094] In addition, encoders that measure various motion-related physical quantities such as current position, movement speed, rotation speed, and rotation angle can be installed on the motor side and the probe side. On the motor side, because the motor rotates, a rotary encoder is installed to easily measure physical quantities related to rotation (rotation speed, rotation angle, etc.). On the probe side, because the probe moves in a straight line, a linear encoder is installed to easily measure physical quantities related to linear motion (parallel motion speed, parallel motion distance, probe position, etc.).

[0095] These encoders provide the measured physical quantities to a controller that controls the movement of the motor or probe in the form of electrical signals. The controller then performs action control based on the obtained physical quantities. Here, the description of "motor side" or "probe side" is used to combine cases where the encoder is built into the motor or probe and cases where it is not. In reality, there may be cases where the encoder is built into the motor or probe and cases where the encoder is placed externally on the motor or probe.

[0096] Reference Figure 6 A simplified explanation of the scanning process using a slider-crank mechanism: The object is scanned along one direction of the probe's parallel movement (X direction) for the Nth line (line #N). Once the Nth line scan is complete, the probe is moved to the Y direction, and then scanned along the opposite direction of the parallel movement (-X direction) for the (N+1)th line (line #N+1). In other words, alternating scans are performed line by line, enabling a so-called zigzag two-dimensional scan.

[0097] Figure 5 The signal processing flow within the trigger control unit 50 is shown.

[0098] Referring to the accompanying drawings, the trigger control unit 50 receives inputs of laser sensing signals and rotary encoder and / or linear encoder pulse signals, generates scan trigger, laser trigger and output trigger, and transmits the generated output trigger signal synchronized with the output trigger to the analog-to-digital converter 30.

[0099] The scan trigger can be generated based on the rotary encoder pulse signal, synchronized with each rise time. Furthermore, the laser trigger can be generated in a form synchronized with the laser sensing signal generated by sensing the laser beam pulses using a photodetector (PD), but after the scan trigger is generated, it can be generated in a form synchronized with the first rise time. Thus, the laser trigger can be generated in a form corresponding to the scan trigger; if a position on the encoder is specified based on the scan trigger, a laser trigger at the specified position is generated. The output trigger can be generated in a form synchronized with the laser trigger. At this time, an output trigger signal synchronized with the output trigger can be generated and transmitted to the analog-to-digital converter 30.

[0100] As another embodiment, the scan trigger can be generated at intervals that are integer multiples of the pulse signal interval of the rotary encoder. In this case, the scan trigger interval can be determined according to the set resolution set externally. This allows for fewer ultrasonic output signals to be output and fewer ultrasonic image signals to be input, thereby reducing the workload of ultrasonic signal generation and processing.

[0101] As another embodiment, the image quality of the real-time generated image signal is evaluated, and the generation interval triggered by the scan is adaptively adjusted to obtain the best quality image while reducing the load of ultrasonic signal generation and processing.

[0102] Furthermore, encoders can be categorized into incremental encoders and absolute encoders based on the method of measuring all the physical quantities. The slit shapes of incremental and absolute encoders differ; the former has uniformly shaped slits, while the latter has uniquely shaped slits. This difference in slit shape determines whether a reference point (origin) is needed when measuring all the aforementioned physical quantities. Incremental encoders require a reference point, while absolute encoders do not. The former has the disadvantage that when a problem occurs (unpredictable power outage, unpredictable motion interruption, etc.), all information about the physical quantities provided to the motor or probe's motion controller is lost (returning to the reference point), requiring all physical quantities to be measured again from the beginning. Conversely, the latter has the advantage that it does not require a reference point. Therefore, even if a problem occurs, unlike the former, there are no such concerns. If the problem is resolved, all physical quantities can be measured again from the time the problem occurred. That is, the continuity of all physical quantity measurements can be guaranteed.

[0103] However, in the latter case, the slit shape makes manufacturing extremely time-consuming, and the design of the related motor's motion control mechanism becomes very complex and difficult. Therefore, implementing the control mechanism also requires considerable effort and time. This ultimately leads to increased costs for achieving the final product, such as production costs, and these costs are significantly higher than using the former under the same conditions. Therefore, most industries prefer the former despite its aforementioned drawbacks.

[0104] However, due to the aforementioned drawbacks, the former approach is difficult to use in fields requiring precise or even continuous control of motor and device (probe) movements. Especially because the stability (stable achievement) of the aforementioned reference point is not easily ensured for many reasons, there are often reliability issues regarding the information generated about the object (the desired information). That is, there is often a problem of inaccurate generated information. The reference point generates a so-called Z-phase pulse signal, which is generated every time the motor rotates once. This signal serves as a reference signal for measuring all physical quantities (reference point function). As mentioned above, the stable achievement of the reference point is not easy, thus causing incomplete control of motor and device (probe) movements, and consequently, there is often a possibility of inaccurate generated information.

[0105] Therefore, in this invention, when acquiring image information about an object using a slider-crank mechanism, certain signal processing is used to compensate for potential problems arising from the inability to stably achieve a reference point, thereby ensuring (improving) the accuracy (reliability) of the image information generated about the object.

[0106] In addition, in order to determine the linearity of the photoacoustic probe 15 for each input signal in response to the sequentially input ultrasonic image signals that have been stored and / or processed, Figure 6 The position on the X coordinate requires an encoder, which can be obtained by using an embodiment that uses only a rotary encoder, or an embodiment that uses both a rotary encoder and a linear encoder. Figure 8 ), An example using only a linear encoder ( Figure 7 ).

[0107] In embodiments using only a rotary encoder, the position of the photoacoustic probe 15 on a straight line can be calculated and used from the Z-phase input belonging to the initial position of the rotary encoder and the A-phase or B-phase input belonging to the incremental position.

[0108] In an embodiment that uses both rotary encoders and linear encoders ( Figure 8 In this system, the position of the photoacoustic probe 15 on a straight line can be calculated and used with the help of the Z-phase input which belongs to the initial position of the rotary encoder and the incremental position of the linear encoder.

[0109] In embodiments using only a linear encoder, the position of the photoacoustic probe 15 on a straight line can be calculated and used with the help of an initial input belonging to the initial position of the linear encoder and the incremental position of the linear encoder.

[0110] In one embodiment, the motion information of the photoacoustic probe can be the rotational motion information of a rotary encoder that detects the rotational motion of the drive motor. The rotary encoder can be an incremental rotary encoder that outputs A-phase signals, B-phase signals, and Z-phase signals.

[0111] Reference Figure 2 and Figure 5 When the trigger control unit 50 generates a scan trigger based on the rotation position information, it can calculate the linear motion position of the photoacoustic probe 15 when generating each output trigger signal, and store the ultrasonic image signal of the calculated linear motion position in a form corresponding to each output trigger signal. The rotation position information is determined by the A-phase signal of the incremental rotary encoder that detects the rotational motion of the drive motor.

[0112] In this case, using an incremental encoder, it may be difficult to ensure the stability (stable implementation) of the reference point. In other words, during the manufacturing process of an incremental rotary encoder, when forming the slit (reference point) that generates the Z-phase pulse signal, it may be formed in a location other than intended due to manufacturing issues, or deformation may occur due to storage problems of the rotary encoder with the slit already formed, or the influence of temperature and humidity, thus distorting the position of the formed slit. If the position of the slit is distorted in this way, it becomes difficult to detect the accurate rotation angle or number of rotations of the motor. That is, if the formation position of the slit, which is set in the form of representing a specific rotation angle, is distorted, then the rotation angle actually indicated by the slit will have a different rotation angle than the intended specific angle. However, the rotary encoder considers that the specific slit to represent the existing specific rotation angle, thus creating a difference between the actual angle and the expected angle of the specific slit. This difference leads to unreliable measurement results of the motor's rotation angle or number of rotations. Moreover, the mechanical vibration that may occur during the movement of the motor and probe can also make the generation of the Z-phase pulse signal unstable.

[0113] This inevitably leads to inaccuracies in the image information generated using the slider-crank mechanism. Because the reference point is unstable, the reference signal for controlling the motor and equipment (probe) is also unstable, ultimately inducing distortions in the generated image information, such as image signal distortion and noise. As a solution to these problems, this invention introduces a virtual Z-phase pulse signal to ensure the accuracy of the generated image information.

[0114] At this point, in an embodiment where a rotary encoder and a linear encoder are used simultaneously ( Figure 8 In the process, the unidirectional rotation of the drive motor begins. After the Z-phase signal of the rotary encoder is generated, the A-phase signal with a preset number of pulses is input. The trigger control unit 50 generates a first trigger event. If the first trigger event is generated, the pulse signal of the linear encoder can be used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

[0115] Furthermore, after stopping the generation of scan triggers, the trigger control unit 50 generates a second trigger event signal in a manner corresponding to the position of the preset photoacoustic probe. If a second trigger event is generated, the pulse signal of the linear encoder can be used as a synchronization signal to generate a scan trigger in a pulse form up to the position of the preset photoacoustic probe.

[0116] As another embodiment, the case of using only a linear encoder ( Figure 7The drive motor begins unidirectional rotation. After generating the initial reference signal of the linear encoder and inputting a pulse signal with a preset number of pulses, the trigger control unit 50 can generate the first trigger event.

[0117] A scan trigger can be generated based on the linear motion position of the probe. The linear motion position of the probe is calculated by a linear encoder pulse signal generated by a linear encoder that detects the linear motion of the photoacoustic probe, and the ultrasonic signal of the linear motion position of each probe is stored in a form corresponding to each output trigger signal.

[0118] As another embodiment, in the embodiment using only a rotary encoder, after the first trigger event is generated, the pulse signal of the rotary encoder is used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

[0119] The trigger control unit 50 can generate a receiving trigger signal for the ultrasonic signal based on the motion information of the photoacoustic probe 15. At this time, the trigger control unit 50 can generate a scanning trigger signal based on the rotational position information and calculate the linear motion position of the photoacoustic probe when generating each scanning trigger signal. The rotational position information is determined by the A-phase signal of the incremental rotary encoder that detects the rotational motion of the drive motor.

[0120] Alternatively, the trigger control unit 50 can also generate a scan trigger signal based on the linear motion position of the probe, wherein the linear motion position of the probe is calculated using a pulse signal generated by a linear encoder that detects the linear motion of the probe. In other words, the scan trigger signal can also be generated solely based on the linear motion position of the probe 10, wherein the linear motion position of the probe 10 is determined by a pulse signal generated by a linear encoder without a rotary encoder.

[0121] Furthermore, the trigger control unit 50 can generate a scan trigger signal by simultaneously combining the rotational motion information of a rotary encoder that detects the rotational motion of the drive motor and the linear motion information of a linear encoder that detects the linear motion of the probe. At this time, the rotary encoder is an incremental rotary encoder that outputs A-phase, B-phase, and Z-phase signals in pulse form, respectively, and the linear encoder outputs linear pulse signals at certain intervals according to the position on the linear motion trajectory of the probe.

[0122] Furthermore, most preferably, the interval of the generated scan trigger signal is always the same as the pulse signal interval of the linear encoder (because as much object state information contained in the ultrasonic signal as possible can be acquired, thereby generating higher resolution image information). However, the concern with this approach is that it requires excessive processing time for the acquired state information and increases the load on the photoacoustic image generation process of the object. This may cause inaccuracies in the generated image information (because errors may occur in all processing steps used to generate image information as the load increases), which would diminish the significance of the present invention. Therefore, considering various factors such as the type and state of the object, it is necessary to appropriately set the amount of state information required for acquisition, which depends on the setting of the wavelength of the generated trigger signal (the output step size of the trigger signal). For example, if the pulse signal interval (resolution) of the linear encoder is 20 [μm], then the trigger control unit 50 generates trigger signals in such a way that the interval of the generated trigger signals is 40 [μm], 60 [μm], 80 [μm], ...

[0123] In addition, to generate a first trigger event, the pulse signal of the linear encoder is used as a synchronization signal, and a trigger signal is generated in pulse form up to the position of a preset probe. After the generation of the trigger signal stops (therefore, the reception of ultrasound stops and the acquisition of the state information of the object belonging to the Nth scan line ends), in order to acquire the state information of the object belonging to the N+1th scan line, a second trigger event signal is generated in a form corresponding to the position of another preset probe 15. If a second trigger event signal is generated, the pulse signal of the linear encoder is used as a synchronization signal, and a trigger signal is generated in pulse form up to the position of a preset probe.

[0124] In the above description, the first trigger event signal and the second trigger event signal are equivalent to virtual Z-phase pulse signals. The acquisition of state information does not begin with the generation of the actual Z-phase pulse signal (physical Z), but rather with the generation of these two event signals. In other words, in this invention, the actual Z-phase pulse signal is only given the notification function of "start scanning action," while the notification function of "start acquiring state information" is given to these two event signals. "Virtual" means that these two event signals perform a portion of the functions required by the actual Z-phase pulse signal, thus functioning as if they were following the actual Z-phase pulse signal.

[0125] If the "start scanning action" and "start acquiring state information" are performed simultaneously (without time difference) by generating the actual Z-phase pulse signal, as mentioned above, the stable realization of the actual Z-phase pulse signal cannot be guaranteed. Therefore, the result will inevitably be unstable and inaccurate acquisition of state information. Thus, it is evident that the two event signals according to the present invention are meaningful in terms of compensation. The generation of these two event signals only applies to a portion of each scan line (…). Figure 2 The state information is obtained by selecting the thicker part of the line (rather than the entire interval).

[0126] Furthermore, according to the present invention, through the above content and Figure 3 It is evident that obtaining a start event signal (trigger event signal) by generating state information according to each scan line differs from generating only one actual Z-phase pulse signal for every two scan lines. This is to ensure the certainty of obtaining state information belonging to each scan line. That is, with the motion characteristics of the slider-crank mechanism, generating only one actual Z-phase pulse signal for every two scan lines, as mentioned above, has the potential for instability in generating the actual Z-phase pulse signal, thus making it unclear which scan line's state information the obtained belongs to. Therefore, to prevent such ambiguity, this invention generates a trigger event signal for "starting to acquire state information" for each scan line.

[0127] Figure 5 A timing diagram is shown for a method of generating an output trigger signal in a high-speed scanning photoacoustic image input device 1. Below, refer to... Figure 2 and Figure 5 The description will focus on an embodiment in which scan triggering is generated by a linear encoder pulse signal.

[0128] The trigger control unit 50 starts counting the number of input pulse signals of the linear encoder by sensing the generation of a pulse signal corresponding to the initial position of the linear encoder. If the number of linear encoder pulse signals reaches a preset count (Counting Num: Z1), the trigger control unit 50 generates a first trigger event. After generating the first trigger event, it generates scan triggers at intervals that are integer multiples of the preset number of linear encoder input pulses.

[0129] Furthermore, a laser trigger is generated in a manner synchronized with the rise time of the next laser sensing signal pulse triggered by the scan. Additionally, an output trigger is generated in a manner synchronized with the laser trigger. Furthermore, the output trigger signal is transmitted to the analog-to-digital converter 30 in a manner synchronized with the output trigger.

[0130] At this point, the scan triggers are calculated, and if the preset number is reached, the generation of scan triggers stops. As another example, scan trigger generation can continue while laser trigger and output trigger generation stops.

[0131] so, Figure 6 In the illustrated embodiment, half the rotation of the drive motor is completed, and the scanning of the Nth scan line is finished. At this point, before the start of the next (N+1)th scan line, along... Figure 6 The scanning module, including the photoacoustic probe 15, moves along a set distance in the Y direction. Therefore, the scanning module can be mounted on a moving module such as a gantry that can move along the Y direction.

[0132] The number of input linear encoder pulses is calculated, and if a preset number is reached, a second trigger event is generated. As another embodiment, the number of scan-triggered pulses is calculated, and if a preset number is reached, a second trigger event is generated.

[0133] After the second trigger event is generated, a scan trigger is generated at intervals that are integer multiples of the set number of linear encoder input pulses. Furthermore, a laser trigger is generated in sync with the rise time of the next laser sensing signal pulse following the scan trigger. Additionally, an output trigger is generated in sync with the laser trigger. Furthermore, the output trigger signal is transmitted to the analog-to-digital converter 30 in sync with the output trigger.

[0134] At this point, the scan triggers are calculated, and if the preset number is reached, the generation of scan triggers stops. As another example, scan trigger generation can continue while laser trigger and output trigger generation stops.

[0135] so, Figure 6 In the embodiment shown, the drive motor completes 2 / 2 rotations, and the N+1th scan line is completed.

[0136] In addition, the control method for the high-speed scanning photoacoustic image input device is used to control... Figures 1 to 8 High-speed scanning photoacoustic image input device, which can be directly applied Figures 1 to 8 The control method described in the high-speed scanning photoacoustic image input device.

[0137] A control method for a high-speed scanning photoacoustic image input device may include the following steps: branching a pulsed laser beam output from a laser generating device into a first laser beam and a second laser beam; branching the second laser beam into a third laser beam and a fourth laser beam; generating a laser sensing signal pulse from the fourth laser beam; inducing the first laser beam and the third laser beam to a first photoacoustic probe and a second photoacoustic probe, respectively; receiving a first ultrasonic signal input from the first photoacoustic probe; receiving a second ultrasonic signal input from the second photoacoustic probe; generating an output trigger signal from the laser sensing signal pulse and the motion information of the first and second photoacoustic probes, i.e., linear encoder pulse signals; and generating a three-dimensional image of the object to be detected from the output trigger signal and the first and second ultrasonic signals.

[0138] The first laser beam splitter VBS1 and the second laser beam splitter VBS2 are variable beam splitters. The first and third laser beams have the same size, but are much larger than the fourth laser beam. In this case, the fourth laser beam is used to sense the laser signal output, rather than to acquire photoacoustic images; it is sufficient to reach a level that the photodetector PD can detect.

[0139] As an example, the size ratio of the first laser beam, the third laser beam, and the fourth laser beam can be 4:4:2.

[0140] Figure 6 and Figure 7 A high-speed scanning photoacoustic image input device 2, 3 is shown according to another embodiment of the present invention.

[0141] Referring to the accompanying drawings, the high-speed scanning photoacoustic image input devices 2 and 3 may include an object area input unit 80 and a scanning area extraction unit 90, which only receive the input of photoacoustic images for the portion of the object area that includes the object to be detected, rather than the entire scanning area.

[0142] The object region input unit 80 receives an input image including the object region of the object to be detected. The scan region extraction unit 90 can extract a scan region from the image of the object region, which is determined by the position values ​​of the start and end points of the region that belongs to the area where the photoacoustic image of the object to be detected is acquired.

[0143] Therefore, the object area input unit 80 may include an additional optical camera capable of capturing the object area. The scan area extraction unit 90 can identify and extract the object to be detected from the image of the object area. Furthermore, a region including the extracted object and a set boundary region can be extracted as the scan area for acquiring photoacoustic images.

[0144] In other words, by using an object area input unit 90, such as an optical camera, to receive the input image of the object area, the scanning area extraction unit 80 can identify the object to be photographed from the input image and extract only the portion of the object to be photographed, thereby setting it as the scanning area. At this time, it can be set to receive the input image only for the scanning area at each scan line unit. As a result, laser pulses can be output only in a preset area at a preset interval, or (and / or) ultrasonic image signals can be generated. Therefore, while minimizing the load on the photoacoustic transceiver, digital conversion unit, and main control unit (image generation unit), photoacoustic images can be input quickly.

[0145] Therefore, the scanning device, including the photoacoustic probe 15, can be positioned along... Figure 6 Mobile modules such as gantry frames that can move in the XY or XYZ directions.

[0146] As another embodiment, the object area input unit 80 and the scan area extraction unit 90 can move the scanning module from the scanning starting point determined by the position of the detected object to the position determined by the set algorithm throughout the entire area.

[0147] In another embodiment, the object area input unit 80 includes a 3D camera such as a time-of-flight (TOF) camera, and the scan area extraction unit 90 can move the scanning device from a scanning starting point determined by the position of the object being detected to a position determined by a set algorithm throughout the entire area. In this case, the position of the scanning starting point can be the XYZ three-dimensional coordinate value moved by the moving module.

[0148] At this time, the scanning of the object is not performed on the entire AR area where the scanning device can be placed, but only on the PR area where the state information of the object needs to be acquired, thereby preventing the generation of unnecessary data that may occur during the acquisition of state information. Therefore, in this invention, the following operation can be performed before scanning the object and acquiring state information: after capturing an image of the object, the size of the PR area where the state information needs to be acquired is determined from the captured image, and state information is acquired only on the PR area of ​​that size (scanning of the object).

[0149] The laser beam conversion unit 11 includes beam splitters VBS1 and VBS2 and a photodetector PD. It generates a laser sensing signal pulse based on the laser pulse of the fourth laser beam detected by the photodetector PD. It converts the ultrasonic signal received as a trigger using the laser sensing signal pulse into an image signal. The image generation unit receives the converted image signal, thereby generating a photoacoustic image of the object. Since the ultrasonic signal contains state information of the object, the resulting state information of the object is generated as a photoacoustic image.

[0150] The high-speed scanning photoacoustic imaging input device according to the present invention is particularly useful for medical diagnosis that requires visualization and immediate confirmation of the internal structure of a living organism; as an example, it can be used for the diagnosis of diabetic foot.

[0151] Diabetic foot (diabetic foot ulcer) refers to a collective term for neuropathy, structural deformities, calluses, skin and nail changes, foot ulcers, infections, and vascular diseases that appear on the feet of diabetic patients. After a diabetic foot ulcer develops, small wounds will not heal and will turn into ulcers. If it is severe, blood circulation will be impaired, and the foot will rot and turn black.

[0152] To diagnose diabetic foot, the first step is to take images of the inside of the patient's foot. Existing methods widely used to generate images of the inside of the body, such as X-ray, CT, and MRI, are difficult to visualize blood vessels accurately. The visualization process is also time-consuming, making it difficult to determine whether the disease is progressing or its extent. Diagnosing diabetic foot through these methods cannot guarantee reliability because it almost entirely relies on confirming and analyzing the presence of diabetes and the patient's current physical condition, and then extrapolating based on the doctor's clinical experience.

[0153] However, if the present invention is used for the diagnosis of diabetic foot, high-resolution images of the inside of the foot can be generated at high speed by combining photoacoustic microscopy and a high-speed scanning device. This improves the slow scanning speed of existing photoacoustic microscopy systems and enables early diagnosis of diabetic foot. Using non-invasive ultrasound and light (laser) within a harmless range, the diagnosis of diabetic foot can be completed within 60 seconds by rapidly imaging the blood vessels in the patient's foot during a face-to-face consultation between the patient and the doctor.

[0154] The preferred embodiments of the present invention, disclosed above to ensure the concreteness of the concept, improve the technical concept of the present invention. It is understood that those skilled in the art to which this invention pertains can implement the preferred embodiments in modified forms without departing from the technical concept (essential characteristics) of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a limiting perspective, and it should be interpreted that the scope of the present invention includes not only the matters disclosed in the claims but also all differences within the equivalent scope.

Claims

1. A high-speed scanning photoacoustic image input device, which converts the unidirectional rotational motion of a drive motor into the linear reciprocating motion of a photoacoustic probe connected to the drive motor, and uses the linear motion of the photoacoustic probe and the vertical motion perpendicular to the linear motion to perform a two-dimensional scan of the object to be detected, thereby generating a three-dimensional image of the object to be detected (the subject of the inspection), characterized in that, include: The photoacoustic transceiver (10, 20) outputs laser pulses toward the object being detected via the laser generator (10), thereby receiving ultrasonic image signals emitted from the object being detected; The analog-to-digital converter (30) receives the input of the ultrasonic image signal and converts it into a digital image signal; The main control unit (40) receives the input of digital image signals and generates ultrasonic image information about the object being detected; The trigger control unit (50) receives motion information input from the photoacoustic probe, generates a scan trigger corresponding to the motion information, receives laser pulse output information input, generates a laser trigger corresponding to the laser pulse output, generates an output trigger signal corresponding to the laser trigger, and outputs it to the analog-to-digital converter (30). The main control unit (40) sequentially synthesizes images corresponding to the ultrasonic image signals according to the scan line units, thereby generating an image of the object being detected, wherein the ultrasonic image signals correspond to the output trigger signals; The unidirectional rotary motion of the drive motor is converted into the linear parallel motion of the photoacoustic probe by a slider-crank mechanism. A pair of photoacoustic probes are positioned on the slider in a spaced-apart manner, along the same direction as the extension of the track. A pair of photoacoustic probes are set at the same distance from the slider, with a distance of twice or less than twice the radius of rotation of the crankshaft. Laser generating unit (10) generates a laser beam; The first beam splitter (VBS1) splits the laser beam into a first laser beam and a second laser beam. The second beam splitter (VBS2) splits the second laser beam into a third laser beam and a fourth laser beam; The optical detector (PD) generates a laser sensing signal by sensing a fourth laser beam; The first junction (OAC1) causes the first laser beam to be reflected and irradiated onto a part of the object being tested, allowing the ultrasonic signal generated in the object being tested to pass through. The second junction (OAC2) causes the third laser beam to be reflected and irradiated onto another part of the object being tested, which is separated from the object by a certain distance, allowing the ultrasonic signal generated in the object to pass through; and The ultrasonic receiving unit (20) receives ultrasonic image signals through the joint (OAC1, OAC2).

2. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The analog-to-digital converter (30) converts the ultrasonic image signal corresponding to the output trigger from the ultrasonic image signal input from the ultrasonic receiver (20) of the photoacoustic transceiver (10, 20) into a digital image signal and transmits it to the main control unit (40).

3. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The main control unit (40) can synthesize the input digital image signals sequentially according to the scan line unit and generate line images, and synthesize the line images of each scan line and generate three-dimensional images.

4. The high-speed scanning photoacoustic image input device according to claim 3, characterized in that, Each even-numbered line image is synthesized in reverse order to generate a line image, which is then combined with the odd-numbered images to generate a 3D image.

5. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, include: Laser generating unit (10) generates a laser beam; A beam splitter that branches a laser beam into a first laser beam and a fourth laser beam; The optical detector (PD) generates a laser sensing signal by sensing a fourth laser beam; The joint allows the first laser beam to be reflected and irradiated onto the object being tested, allowing the ultrasonic signal generated on the object to pass through; and The ultrasonic receiving unit (20) receives ultrasonic image signals passing through the joint.

6. The high-speed scanning photoacoustic image input device according to claim 5, characterized in that, The joint includes a mating surface that engages with two prisms. The mating surface is coated with aluminum material, which causes the irradiated laser beam to be reflected and allows the ultrasonic signal to pass through.

7. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The image generation unit of the main control unit calculates the position of the photoacoustic probe corresponding to the output trigger signal, and stores the ultrasonic image signal of the calculated position in a form corresponding to each output trigger signal.

8. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The motion information of the photoacoustic probe is the rotational motion information of the rotary encoder that detects the rotational motion of the drive motor. The rotary encoder is an incremental rotary encoder that outputs A-phase signal, B-phase signal, and Z-phase signal.

9. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, A scan trigger is generated based on the rotational position information, which is determined by the A-phase signal of the incremental rotary encoder that detects the rotational motion of the drive motor. The linear motion position of the photoacoustic probe when each output trigger signal is generated is calculated, and the ultrasonic image signal of the calculated linear motion position is stored in a form corresponding to each output trigger signal.

10. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, A scan trigger is generated based on the linear motion position of the probe. The linear motion position of the probe is calculated by a linear encoder pulse signal generated by a linear encoder that detects the linear motion of the photoacoustic probe, and the ultrasonic signal of the linear motion position of each probe is stored in a form corresponding to each output trigger signal.

11. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The motion information of the photoacoustic probe includes the rotational motion information of the rotary encoder that detects the rotational motion of the drive motor and the linear motion information of the linear encoder that detects the linear motion of the photoacoustic probe. The rotary encoder is an incremental rotary encoder that outputs A-phase signals, B-phase signals and Z-phase signals in pulse form respectively. The linear encoder outputs linear pulse signals at certain intervals according to the position on the linear motion trajectory of the probe.

12. The high-speed scanning photoacoustic image input device according to claim 11, characterized in that, The drive motor begins unidirectional rotation. After the Z-phase signal of the rotary encoder is generated, the A-phase signal with a preset number of pulses (Z1) is input. The trigger control unit generates a first trigger event. If the first trigger event is generated, the pulse signal of the linear encoder is used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

13. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, The scan trigger is generated at intervals that are integer multiples of the pulse signal intervals of the linear encoder.

14. The high-speed scanning photoacoustic image input device according to claim 13, characterized in that, After stopping the generation of scan triggers, the trigger control unit generates a second trigger event signal in a manner corresponding to the pre-set position of the photoacoustic probe. If a second trigger event is generated, the pulse signal of the linear encoder can be used as a synchronization signal to generate a scan trigger in pulse form up to the position of the preset photoacoustic probe.

15. The high-speed scanning photoacoustic image input device according to claim 1, characterized in that, include: The object area input unit receives an input including an image of the object area of ​​the detected object; as well as The scanning area extraction unit extracts a scanning area from the image of the object region, which is determined by the position values ​​of the start and end points of the region belonging to the area where the photoacoustic image of the object being detected is acquired.

16. A control method for a high-speed scanning photoacoustic image input device, wherein photoacoustic images are acquired using the high-speed scanning photoacoustic image input device according to any one of claims 1 to 15.

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