WO2017037782A1

WO2017037782A1 - Scanning-type observation device

Info

Publication number: WO2017037782A1
Application number: PCT/JP2015/074432
Authority: WO
Inventors: 西村　淳一
Original assignee: オリンパス株式会社
Priority date: 2015-08-28
Filing date: 2015-08-28
Publication date: 2017-03-09
Also published as: JPWO2017037782A1

Abstract

This scanning-type observation device (1) is provided with: a scanning unit (4) that rotationally scans, at a constant angular velocity, a beam (L) for irradiating a subject (A); a detection unit (5) that detects a signal wave (L') from the subject (A); an image generation unit (6) that generates an image of the subject (A) on the basis of the signal wave (L'); and a rotation angle setting unit (8) that sets a rotation angle for the image of the subject (A) within the image. The image generation unit (6) calculates a shift time on the basis of the set rotation angle and the angular velocity of the beam (L) and generates an image by associating the signal wave (L') with the irradiation position of the beam (L) at a time shifted by the shift time from the time of detection by the detection unit (5).

Description

Scanning observation device

The present invention relates to a scanning observation apparatus.

2. Description of the Related Art Conventionally, there is known a scanning endoscope that acquires an image of a subject by spiral scanning with a light or ultrasonic beam on the subject (see, for example, Patent Document 1). In the endoscope of Patent Document 1, the image is rotated so that the vertical direction of the image in the image matches the vertical direction of the distal end surface of the endoscope.
In the body, the distal end surface of the endoscope rotates with respect to the subject due to torsion of the endoscope or the like, so that the image of the subject in the image rotates. Even in such a case, processing for rotating the image is performed to adjust the orientation of the image of the subject in the image.

International Publication No. 2010/029096

In the image rotation process, generally, an arithmetic process for calculating the position after rotation of each pixel using a trigonometric function from the original position of each pixel is performed. In order to perform such a calculation process on a high-frame-rate endoscopic image displayed as a live video, a high-performance processor or dedicated hardware capable of high-speed computation is required, which is expensive. There is a problem.

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a scanning observation apparatus capable of executing image rotation processing at high speed by simple calculation.

In order to achieve the above object, the present invention provides the following means.
The present invention includes a scanning unit that rotates and scans a beam for irradiating a subject at a constant angular velocity, a detection unit that detects a signal wave generated in the subject by irradiation of the beam, and the detection unit that detects the detection unit An image generation unit that generates an image of the subject based on a signal wave; and a rotation angle setting unit that sets a rotation angle of the image of the subject in the image generated by the image generation unit. A beam calculating unit that calculates a shift time based on the rotation angle set by the rotation angle setting unit and the angular velocity of the beam, and the beam at a time when the signal wave is shifted from the detection time by the detection unit by the shift time. There is provided a scanning observation apparatus that generates the image by associating with an irradiation position on the scanning trajectory.

According to the present invention, the beam is scanned on the subject by the scanning unit, and the signal wave from the subject is detected by the detection unit. The image generation unit generates an image of the subject by associating the detected signal wave with a beam irradiation position on the subject.

In this case, the signal wave is associated with a position shifted in the scanning direction from the actual beam irradiation position by an angle corresponding to the rotation angle set by the rotation angle setting unit. Since the beam is rotationally scanned at a constant angular velocity, the signal wave detected by the detection unit is shifted by a shift time equal to the ratio of the rotation angle received from the rotation angle setting unit and the angular velocity of the beam received from the detection unit. By doing so, the image of the subject can be uniformly rotated by the rotation angle. In this way, image rotation processing can be executed at high speed by a simple calculation in which the signal wave to be associated and the irradiation position are shifted by an equal shift time in the time direction.

In the above invention, the image generation unit further includes a rotation adjustment unit, and based on the value of the rotation angle θ received from the rotation angle setting unit and the value of the angular velocity ω of the laser beam received from the detection unit, The shift time Δt may be calculated based on an equation.
Δt = θ / ω
In this way, it is possible to uniformly perform image rotation processing based on the shift time calculated by the rotation adjustment unit.

In the above invention, the shift time may be changeable in units of one frame of image so that the image generator generates each image with a different shift time.
In this way, the rotation angle of the subject image in the image can be changed in units of one frame, and the rotation angle of the subject image in the image displayed as a live image on the display unit can be changed in substantially real time. Can be changed.
In the above invention, the scanning unit may rotationally scan the beam along a spiral or concentric scanning locus.

According to the present invention, it is possible to execute an image rotation process at a high speed by a simple calculation.

1 is an overall configuration diagram of a scanning observation apparatus according to an embodiment of the present invention. It is a block diagram which shows the detailed structure of the scanning observation apparatus of FIG. It is a figure which shows the structure of the scanner in the scanning observation apparatus of FIG. FIG. 3B is a cross-sectional view taken along line III-III in FIG. 3A. It is a figure which shows an example of the brightness | luminance value data set produced | generated by the rotation adjustment part, and the coordinate data set produced | generated by the control part. It is a figure which shows an example of the coordinate data set which shifted luminance value data set and detection time, and the coordinate by shift time (DELTA) t. It is a figure which shows the alternating voltage applied to the scanner of FIG. 3A from a D / A converter. It is a figure which shows an example of the graphic for setting the rotation angle by a rotation angle setting part. It is a figure explaining the rotation process of an image.

Below, scanning type observation device 1 concerning one embodiment of the present invention is explained with reference to drawings.
As shown in FIG. 1, the scanning observation apparatus 1 according to the present embodiment emits a laser beam (beam) L irradiated to the subject A from the distal end of the insertion portion 21 of the endoscope 2 in a spiral scanning locus B. Is an optical scanning endoscope apparatus that acquires an image of the subject A.

As shown in FIG. 2, the scanning observation apparatus 1 includes a light source unit 3, an optical scanning unit (scanning unit) 4 that scans the laser light L output from the light source unit 3 and irradiates the subject A, and a subject. A detection unit (detection unit) 5 that detects the reflected light (signal wave) L ′ of the laser light L from A, and an image that generates an image of the subject A based on the reflected light L ′ detected by the detection unit 5 A generation unit (image generation unit) 6, a control unit 7 that controls the optical scanning unit 4, the detection unit 5, and the image generation unit 6, and a rotation angle setting unit 8 that sets the rotation angle θ of the image of the subject A in the image. And a display unit 9.
A part of the optical scanning unit 4 and the detection unit 5, the image generation unit 6, and the control unit 7 are accommodated in a housing 10 connected to the endoscope 2.

The light source unit 3 includes three laser light sources (not shown) that respectively emit red (R), green (G), and blue (B) continuous wave laser beams. The light source unit 3 combines the R, G, and B laser beams to generate white laser beam L, and emits the white laser beam L. For example, a semiconductor solid-state laser light source or a laser diode is used as the laser light source.

In the present embodiment, a case where a white light image of the subject A is acquired will be described, but other types of images may be acquired. For example, an image of fluorescence excited by laser light may be acquired, or an infrared image or NBI (narrow band imaging) image may be acquired using laser light of a specific color.

The optical scanning unit 4 includes a waveform generator 41 that generates a digital waveform based on a control signal from the controller 7, a D / A converter 42 that D / A converts the digital waveform to generate an alternating voltage, a light source And a scanner 43 that irradiates the subject A while scanning the laser beam L from the unit 3.

The waveform generation unit 41 generates a digital waveform having a frequency and amplitude specified by the control signal received from the control unit 7.
The D / A converter 42 generates an alternating voltage by converting the digital waveform generated by the waveform generator 41 into a voltage waveform. The generated alternating voltage is supplied to the scanner 43 via the

electric cables

13A and 13B.

As shown in FIGS. 3A and 3B, the scanner 43 is disposed inside the distal end portion 21 a of the insertion portion 21. The scanner 43 includes an illumination optical fiber 44 disposed in the insertion portion 21 along the longitudinal direction, an actuator 45 that vibrates the illumination optical fiber 44, and the illumination optical fiber 44 and the actuator 45 of the insertion portion 21. And a fixing portion 46 that is fixed to the outer cylinder.

Reference numerals

11 and 12 denote condensing lenses that focus the laser light L emitted from the tip of the illumination optical fiber 44 onto the subject A.

The proximal end of the illumination optical fiber 44 is connected to the light source unit 3. The laser light L incident on the proximal end surface of the illumination optical fiber 44 from the light source unit 3 is guided from the proximal end to the distal end of the illumination optical fiber 44, and from the distal end surface of the illumination optical fiber 44 to the insertion portion 21. It is injected toward the front of the tip.

The actuator 45 includes a rectangular cylindrical elastic portion 47 and four

piezoelectric elements

48A and 48B fixed to the outer peripheral surface of the elastic portion 47.
The illumination optical fiber 44 passes through the elastic portion 47, and the elastic portion 47 is formed on the outer peripheral surface of the illumination optical fiber 44 at a position spaced from the distal end of the illumination optical fiber 44 to the proximal end side. It is fixed. A portion of the elastic portion 47 closer to the base end side than the piezoelectric elements 48 </ b> A and 48 </ b> B is fixed to the outer cylinder of the insertion portion 21 via the fixing portion 46. As a result, the elastic portion 47 and the distal end portion of the illumination optical fiber 44 are supported in a cantilever shape and can swing.

The

piezoelectric elements

48A and 48B are plate-like and polarized in the thickness direction. In FIG. 3B, an arrow P indicates the polarization direction of the

piezoelectric elements

48A and 48B. As shown in FIG. 3B, the

piezoelectric elements

48A and 48B have four elastic portions 47 so that the polarization directions of the two

piezoelectric elements

48A or 48B facing the radial direction of the illumination optical fiber 44 are the same. One sheet is fixed to each of the two outer surfaces. An A-phase electrical cable 13A is connected to the two X scanning piezoelectric elements 48A facing in the X direction, and a B phase electrical cable is connected to the two Y scanning piezoelectric elements 48B facing in the Y direction. The cable 13B is connected. The X direction and the Y direction are radial directions of the illumination optical fiber 44 and are directions orthogonal to each other.

Here, the waveform generator 41 generates two digital waveforms of A phase and B phase. The D / A converter 42 is provided for the A phase and the B phase, respectively. The A-phase D / A converter 42 D / A-converts the A-phase digital waveform, and the generated A-phase alternating voltage is supplied to two X-scanning piezoelectric elements 48A via the electric cable 13A. To be supplied. The B-phase D / A converter 42 D / A converts the B-phase digital waveform, and the generated B-phase alternating voltage is supplied to two Y-scanning piezoelectric elements 48B via the electric cable 13B. To be supplied.

The piezoelectric element 48A for X scanning expands and contracts in the longitudinal direction (Z direction) of the illumination optical fiber 44 by application of an A-phase alternating voltage. At this time, when one of the two piezoelectric elements 48A contracts in the Z direction and the other extends in the Z direction, the elastic portion 47 is excited to bend in the X direction with the position of the fixed portion 46 as a node. Is done. The bending vibration of the elastic portion 47 is transmitted to the illumination optical fiber 44. As a result, the tip of the illumination optical fiber 44 bends and vibrates in the X direction, the tip of the optical fiber 11 vibrates in the X direction, and the laser light L emitted from the tip is scanned in the X direction.

The Y-scanning piezoelectric element 48B expands and contracts in the longitudinal direction (Z direction) of the illumination optical fiber 44 when a B-phase alternating voltage is applied. At this time, one of the two piezoelectric elements 48B contracts in the Z direction and the other expands in the Z direction, so that the elastic portion 47 is excited by bending vibration in the Y direction with the position of the fixed portion 46 as a node. Is done. The bending vibration of the elastic portion 47 is transmitted to the illumination optical fiber 44. As a result, the distal end portion of the illumination optical fiber 44 bends and vibrates in the Y direction, the distal end of the illumination optical fiber 44 vibrates in the Y direction, and the laser light L emitted from the distal end is scanned in the Y direction.

The detection unit 5 includes a light receiving unit 51 that receives the reflected light L ′ of the laser light L reflected from the subject A, and a photodetector 52 that detects the reflected light L ′ received by the light receiving unit 51. Yes.
The light receiving unit 51 is a light receiving optical fiber (hereinafter also referred to as “light receiving optical fiber 51”) arranged in parallel with the illumination optical fiber 44 and inside the insertion unit 21. A plurality of light receiving optical fibers 51 are provided so as to surround the illumination optical fiber 44 in the circumferential direction. A light receiving lens (not shown) is disposed on the front end side of each light receiving optical fiber 51, and the reflected light L ′ from the subject A enters the front end surface of the light receiving optical fiber 51 through the light receiving lens. Yes. The base end of the light receiving optical fiber 51 is connected to the photodetector 52. The reflected light L ′ incident on the front end surface of the light receiving optical fiber 51 is guided from the front end to the base end of the light receiving optical fiber 51 and enters the photodetector 52.

The photodetector 52 detects the reflected light L ′ at regular time intervals, and outputs an electrical signal corresponding to the detected intensity of the reflected light L ′ to the A / D converter 61 in the image generation unit 6. The photodetector 52 is, for example, a color separation element (not shown) that separates the white reflected light L ′ from the light receiving optical fiber 51 into three colors of R, G, and B, and color separation by the color separation element. And three photodiodes (not shown) that photoelectrically convert each reflected light L ′ of R, G, and B. With this configuration, the photodetector 52 detects the reflected light L ′ of R, G, and B separately and simultaneously, and outputs three electrical signals to the A / D converter 61.

The image generation unit 6 includes an A / D converter 61 that performs A / D conversion on the electrical signal output from the photodetector 52, a rotation adjustment unit 62 that adjusts the rotation angle of the image of the subject A in the image, and an image. And an image forming unit 63 for forming the image.

The A / D converter 61 obtains a digital value indicating the intensity of the reflected light L ′ by digitally converting each of the three electrical signals from the photodetector 52. The obtained digital values are the R, G, and B luminance values of each pixel of the image formed by the image forming unit 63. Hereinafter, the R, G, and B luminance values detected at the time ti by the photodetector 52 are referred to as luminance values S (ti). The A / D converter 61 transmits the obtained luminance value S (ti) to the rotation adjustment unit 62.

As shown in FIG. 4A, the rotation adjusting unit 62 determines that the luminance value S (ti) (i = 1, 2, 3,...) Received from the A / D converter 61 and the luminance value S (ti) are A luminance value data set D1 in which the detection times ti (i = 1, 2, 3,...) Detected by the photodetector 52 are associated with each other is generated. The detection time ti is acquired from the control unit 7, for example.

Also, the rotation adjustment unit 62 receives from the control unit 7 a coordinate data set D2 (detailed later) in which the coordinates P (ti) of each pixel for one frame of the image are associated with the detection time ti. The rotation adjustment unit 62 performs the following rotation processing based on the rotation angle θ set by the rotation angle setting unit 8 to generate a coordinate data set D2 ′.

In the rotation process, the rotation adjusting unit 62 is based on the following equation from the value of the rotation angle θ received from the rotation angle setting unit 8 and the value of the angular velocity ω (described later) of the laser light L received from the control unit 7. A shift time Δt is calculated.
Δt = θ / ω

Next, the rotation adjustment unit 62 relatively shifts the coordinates P (ti) and the detection time ti in the time direction by the calculated shift time Δt in the coordinate data set D2. As a result, as shown in FIG. 4B, the correspondence between the coordinates P (ti) and the detection time ti is uniformly changed, and each coordinate P (ti) is shifted by the shift time Δt before the actual detection time ti. Or later time ti + Δt. As described above, by associating the coordinate P (ti) with the time ti + Δt, the image of the subject A in the image formed by the image forming unit 63 is rotated by the rotation angle θ as described later. When the rotation angle θ is 0 °, the shift time Δt is zero, and the coordinate data set D2 'is the same as the coordinate data set D2.

Next, the rotation adjustment unit 62 associates the brightness value S (ti) and the coordinate P (ti + Δt) associated with the same detection time ti in the brightness value data set D1 and the coordinate data set D2 ′, thereby generating an image. Generate a data set. The rotation adjusting unit 62 transmits the generated image data set to the image forming unit 63.

Here, the rotation adjusting unit 62 sets the shift time Δt based on the rotation angle θ for each frame of the image so as to generate images at different shift times. Accordingly, the shift time Δt can be changed in units of one image frame, and the rotation angle θ of the image of the subject A can be changed in units of one image frame.

The image forming unit 63 forms an image by assigning each pixel a luminance value S (ti) corresponding to the pixel coordinate P (ti + Δ) based on the image data set. The image forming unit 63 transmits the formed image to the display unit 9 and causes the display unit 9 to display the image.

The control unit 7 controls the photodetector 52 so that the photodetector 52 detects the reflected light L ′ at regular time intervals.
In addition, the control unit 7 sets the frequency and amplitude of the alternating voltage, generates a control signal for generating a digital waveform having the set frequency and amplitude, and transmits the control signal to the waveform generation unit 41.

Here, the control unit 7 generates two control signals that cause the waveform generation unit 41 to generate A-phase and B-phase digital waveforms whose amplitude changes in a sine wave shape and whose phases are shifted from each other by π / 2. To do. As a result, as shown in FIG. 5, the A / B converter 42 generates alternating voltages of the A phase and the B phase, the amplitude of which gradually changes in a sine wave shape and whose phases are shifted from each other by π / 2. . When such an alternating voltage is applied to the

piezoelectric elements

48A and 48B, the tip of the illumination optical fiber 44 spirally vibrates, and the laser light L is scanned along the spiral scanning locus B on the subject A. It is like that.

Further, the control unit 7 generates the control signal so that the waveform generation unit 41 generates a digital waveform having a constant frequency. Thereby, the laser beam L is scanned along the scanning locus B at a constant angular velocity ω. The control unit 7 calculates the angular velocity ω of the laser light L from the frequency of the digital waveform, and transmits the calculated value of the angular velocity ω to the rotation adjustment unit 62.

The control unit 7 calculates the irradiation position on the scanning locus B of the laser beam L at the detection time ti of the reflected light L ′ by the photodetector 52 based on the control signals for the A phase and the B phase. The control unit 7 sets the irradiation position at each detection time ti as the coordinate P (ti) of each pixel in the image, and associates the coordinate P (ti) of each pixel with the detection time ti as shown in FIG. 4A. The coordinate data set D2 is generated, and the generated coordinate data set D2 is transmitted to the image forming unit 63.

The waveform generating unit 41, the rotation adjusting unit 62, the image forming unit 63, and the control unit 7 described above are realized by a computer. Specifically, the computer includes a middle processing unit (CPU), a main storage device such as a RAM, and an auxiliary storage device. The auxiliary storage device is a computer-readable non-transitory storage medium such as a hard disk or various memories, and a control program for controlling the optical scanning unit 4 and the detection unit 5 and an image for forming an image. Stores processing programs. When these programs are loaded from the auxiliary storage device to the main storage device and activated, the CPU executes the above-described processing of each of the

units

41, 62, 63, and 7 according to the program. Or each

part

41, 62, 63, 7 may be comprised from dedicated hardware like ASIC (application specific integrated circuit).

The rotation angle setting unit 8 includes a GUI (graphical user interface) provided in the display unit 9 and displays a graphic for allowing the user to set the rotation angle θ on the screen of the display unit 9. For example, as shown in FIG. 6, the graphic includes a scale bar 81 from −180 ° to + 180 ° and a slider 82 movable within the scale bar 81. The user can set the rotation angle θ within a range from −180 ° to + 180 ° by moving the slider 82 within the scale bar 81 using an input device such as a mouse connected to the display unit 9. It can be done. The rotation angle θ is initially set to 0 °. The rotation angle setting unit 8 transmits the set value of the rotation angle θ to the rotation adjustment unit 62.

Next, the operation of the scanning observation apparatus 1 configured as described above will be described.
When the waveform generator 41 starts generating a digital waveform in response to a control signal from the controller 7, an alternating voltage is applied to the

piezoelectric elements

48A and 48B of the scanner 43, so that the tip of the illumination optical fiber 44 spirally vibrates. To do. As a result, the white laser light L is scanned along the spiral scanning locus B on the surface of the subject A facing the distal end surface of the insertion portion 21. The reflected light L ′ of the laser light L reflected from the surface of the subject A is received by the light receiving optical fiber 51, detected by the photodetector 52, and an electrical signal of the reflected light L ′ is transmitted into the image generation unit 6. Is done.

In the image generation unit 6, the electric signal is digitally converted by the A / D converter 61, whereby the luminance value S (ti) of each pixel of the image is obtained. In the rotation adjustment unit 62, a luminance value data set D1 that is time-series data of the luminance value S (ti) at each detection time ti is generated.

On the other hand, every time scanning of the laser beam L for one frame of the image is completed in the control unit 7, a coordinate data set D2 which is time series data of the coordinates P (ti) at each detection time ti is generated. The set D2 is transmitted to the rotation adjustment unit 62.
The rotation adjusting unit 62 generates a coordinate data set D2 ′ from the coordinate data set D2, and adds the brightness value S () at the same time ti in the brightness value data set D1 to each coordinate P (ti + Δt) in the coordinate data set D2 ′. By associating ti), an image data set for one image frame is generated.

Next, the image forming unit 63 forms an image based on the image data set, and the formed image is displayed on the display unit 9. Since Δt = 0 in the initial state, each luminance value S (ti) is associated with the coordinate P (ti) at the actual detection time ti as indicated by a white circle in FIG. In this case, the orientation of the image of the subject A in the image is the same as the actual orientation of the subject A with respect to the distal end surface of the insertion unit 21.

Here, when the user wants to rotate the image of the subject A in the image displayed on the display unit 9, the rotation angle setting unit 8 sets the rotation angle θ to a desired angle other than 0 °.
When the rotation angle θ is set to an angle other than 0 °, the rotation adjustment unit 62 causes the coordinates P (ti) and the detection time ti in the coordinate data set D2 to be in the time direction by the shift time Δt based on the rotation angle θ. Shift to. Thereby, in the image formation, each luminance value S (ti) is associated with the coordinate P (ti + Δt) rotated by the rotation angle θ from the actual coordinate P (ti) as shown by a black circle in FIG. . Thereby, an image in which the subject A is rotated by the rotation angle θ is formed.

Thus, according to the present embodiment, since the laser beam L is rotationally scanned at a constant angular velocity ω, the detection time ti associated with each coordinate P (ti) is obtained from the rotational angle setting unit 8. By a simple calculation process that is uniformly changed only by the shift time Δt equal to the ratio between the value of the received rotation angle θ and the value of the angular velocity ω of the laser light L received from the detection unit 5 (that is, only the addition calculation). An image obtained by uniformly rotating the entire image of the subject A can be formed. Therefore, it is possible to form an image that has been subjected to the above rotation processing at a high-speed frame rate necessary for live video, without using a high-performance CPU or dedicated hardware, even with an inexpensive hardware configuration. There is an advantage.

In the present embodiment, the coordinate P (ti) in the coordinate data set D2 and the detection time ti are shifted in the time direction. Instead, the luminance value S in the luminance value data set D1 is used. (Ti) and detection time ti may be shifted in the time direction.
Even if it does in this way, the same effect can be acquired.

In this embodiment, the optical scanning unit 4 scans the laser light L along the spiral scanning locus B. Alternatively, the optical scanning unit 4 may scan along the concentric scanning locus. Good. The configuration of the scanner 43 can be appropriately changed according to the shape of the scanning locus. For example, instead of the scanner 43 using the piezoelectric actuator 45, an optical scanner using a photonic crystal may be used.

In the present embodiment, the user sets the rotation angle θ, but instead, the rotation angle setting unit 8 detects the direction of the subject A in the image and sets the detected direction to a predetermined value. It may be configured to automatically set the rotation angle θ so as to match the direction of.

Further, in the present embodiment, the scanning unit including the optical scanning unit 4 that scans the laser light L to acquire an optical image is provided. Instead, the ultrasonic beam is scanned on the subject A. In addition, a scanning unit including an ultrasonic scanning unit that acquires an ultrasonic image by detecting an echo (signal wave) from the subject A may be provided.
In the present embodiment, the endoscope apparatus has been described. However, the image rotation processing described above is an arbitrary observation in which an image of the subject A is acquired by rotating and scanning a light or ultrasonic beam on the subject A. It can be applied to the device.
Moreover, in this embodiment, you may be comprised so that at least one part of operation which a user performs manually may be automatically performed by the control part 7. FIG.

DESCRIPTION OF SYMBOLS 1 Scanning observation apparatus 2 Endoscope 3 Light source part 4 Optical scanning unit (scanning part)
41 Waveform generator 42 D / A converter 43 Scanner 44 Illumination optical fiber 45 Actuator 46 Fixing part 47

Elastic part

48A, 48B Piezoelectric element 5 Detection unit (detection part)
51 light receiving unit, light receiving optical fiber 52 photodetector 6 image generation unit (image generation unit)
61 A / D converter 62 Rotation adjustment unit 63 Image forming unit 7 Control unit 8 Rotation angle setting unit 9 Display unit 10

Housing

11 and 12

Condensing lenses

13A and 13B Electric cable L Laser light (beam)
L 'Reflected light (signal wave)

Claims

A scanning unit that rotationally scans a beam for irradiating a subject at a constant angular velocity;
A detection unit for detecting a signal wave generated in the subject by irradiation of the beam;
An image generation unit that generates an image of the subject based on the signal wave detected by the detection unit;
A rotation angle setting unit that sets a rotation angle of the image of the subject in the image generated by the image generation unit;
Time when the image generation unit calculates a shift time based on the rotation angle and the angular velocity of the beam set by the rotation angle setting unit, and shifts the signal wave by the shift time from the detection time by the detection unit A scanning observation apparatus that generates the image by associating with an irradiation position on a scanning trajectory of the beam.
The image generation unit further includes a rotation adjustment unit, and based on the value of the rotation angle θ received from the rotation angle setting unit and the value of the angular velocity ω of the laser beam received from the detection unit, based on the following formula: The scanning observation apparatus according to claim 1, wherein the shift time Δt is calculated.
Δt = θ / ω
The observation apparatus according to claim 1 or 2, wherein the image generation unit generates an image at the shift time that is different for each frame.
4. The scanning observation apparatus according to claim 1, wherein the scanning unit rotationally scans the beam along a spiral scanning locus.