JP6619963B2 - Photoacoustic imaging device - Google Patents

Description

  The present invention relates to a photoacoustic imaging apparatus, and more particularly to a photoacoustic imaging apparatus including a light source unit.

  Conventionally, a photoacoustic imaging apparatus provided with a light source unit is known (see, for example, Patent Document 1).

  Patent Document 1 discloses a photoacoustic imaging apparatus including a laser light source unit guided by an optical fiber and a detection unit that detects an acoustic wave from a detection target of a subject. The photoacoustic imaging apparatus is arranged on the detection direction side (the subject side of the detection target) of the laser light source unit and the detection unit in order to irradiate the light from the laser light source unit to the shallow detection target immediately below the center of the detection unit. The light guide plate is further provided.

JP2013-48892A

  However, in the photoacoustic imaging apparatus of Patent Document 1, it is necessary to provide a light guide plate in order to irradiate light to a shallow detection object just below the center of the detection unit, and thus the configuration of the apparatus is complicated. There is.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide light at a shallow position directly below the center of the detection unit with a simple device configuration without providing a light guide plate. It is to provide a photoacoustic imaging apparatus capable of irradiation.

  In order to achieve the above object, a photoacoustic imaging apparatus according to one aspect of the present invention includes a light source unit and a detection unit that is arranged side by side with the light source unit and detects an acoustic wave. It arrange | positions so that the area | region of the surface vicinity of the detection target object right under the center of a detection part may be irradiated with the light of 50% or more of intensity | strength.

  In the photoacoustic imaging apparatus according to one aspect of the present invention, as described above, the light source unit is arranged so as to be aligned with the detection unit, and light having an intensity of 50% or more of the maximum intensity is directly below the center of the detection unit. It arrange | positions so that the area | region of the surface vicinity of the detection target object Q may be irradiated. Thereby, when irradiating light by an optical semiconductor element light source such as a light emitting diode element having a relatively wide orientation angle, the light source part and the detection part are arranged close to each other without going through the light guide plate, Light having an intensity of 50% or more of the maximum intensity can be applied to the area near the surface of the detection object Q immediately below the center of the detection unit. As a result, it is possible to irradiate light at a shallow position directly below the center of the detection unit with a simple device configuration without providing a light guide plate.

In the photoacoustic imaging apparatus according to the above aspect, the light source unit and the detection unit are preferably arranged on the same plane extending in the lateral direction in which the light source unit and the detection unit are arranged, and emit light from the light source unit. An angle formed between the light emitting surface to be formed and the plane is α, a first direction in which light having the maximum intensity is emitted from the light source unit, and a second direction in which light having 50% of the maximum intensity is emitted from the light source unit. , X is the distance from the position immediately below the center of the detection unit to the end on the detection unit side of the light source unit in the horizontal direction, and L is the width of the light emission surface of the light source unit. It arrange | positions in the position which satisfy | fills the following formula | equation which shows the irradiation depth of the light to.
{X / (tan (α + β))} − L × sin α ≦ 10.0 (mm)
If comprised in this way, a light source part will be easily arrange | positioned in the position used as the irradiation depth of 10.0 mm or less just under the center of a detection part by arrange | positioning a light source part with respect to a detection part so that the above Formula may be satisfy | filled. be able to.

  In the photoacoustic imaging apparatus according to the above aspect, the light source unit preferably includes a plurality of optical semiconductor element light sources, and the plurality of optical semiconductor element light sources are arranged in a row in a plan view. If comprised in this way, light must be diffused with a light-guide plate, and compared with the case where the optical fiber which is hard to stabilize light quantity is used, according to this invention, from the range along the array direction of a wide row | line | column form It is possible to irradiate light having a stable intensity directly below the center of the detection unit.

  In the photoacoustic imaging apparatus according to the above aspect, preferably, the detection unit includes an acoustic lens capable of converging the acoustic wave on the detection unit, and the acoustic lens reflects light from the light source unit and transmits the acoustic wave. It includes a reflective part. If comprised in this way, since the light from a light source part can be reflected by a reflection part, light will be absorbed by an acoustic lens and the artifact resulting from a photoacoustic wave being generated from an acoustic lens will be suppressed. Can do. In particular, when the light source unit is brought close to the detection unit, the amount of light applied to the acoustic lens increases, so that artifacts caused by the generation of photoacoustic waves from the acoustic lens are effectively suppressed. Can do.

  The photoacoustic imaging apparatus according to the above aspect preferably further includes a probe main body provided with a detection unit and a light source unit provided with a light source unit, and the light source unit is detachably attached to the outer surface of the probe main body. It has been. If comprised in this way, since the light source unit containing an optical semiconductor element light source is attached to a probe main body so that attachment or detachment is possible, position adjustment of the light source part with respect to a detection part can be performed easily.

  In the photoacoustic imaging apparatus according to the above aspect, the light source section preferably includes a light semiconductor element light source of any one of a light emitting diode element (LED element), a semiconductor laser element, and an organic light emitting diode element. If comprised in this way, since a light emitting diode element, a semiconductor laser element, and an organic light emitting diode element are light sources which can carry out pulse light emission with a comparatively simple drive mechanism, it suppresses that a light source part enlarges. be able to. As a result, it is possible to suppress the apparatus from becoming large.

  In the photoacoustic imaging apparatus according to the above aspect, the light source unit preferably includes a laser light source that guides light using an optical fiber. If comprised in this way, light with comparatively strong intensity | strength can be light-guided and irradiated with an optical fiber. Further, by adjusting the direction of the laser light source, it is possible to easily irradiate light at a shallow position directly below the center of the detection unit.

  According to the present invention, as described above, it is possible to provide a photoacoustic imaging apparatus capable of irradiating light at a shallow position directly below the center of the detection unit with a simple apparatus configuration without providing a light guide plate. .

It is the block diagram which showed the whole structure of the photoacoustic imaging device by 1st and 2nd embodiment of this invention. It is the schematic diagram which showed the use condition of the photoacoustic imaging device by 1st Embodiment of this invention. It is the enlarged view which showed the probe and light source unit of the photoacoustic imaging device by 1st Embodiment of this invention. It is the top view which showed the probe and light source unit of the photoacoustic imaging device by 1st Embodiment of this invention. It is a figure for demonstrating the orientation characteristic of the light emitting diode as an optical semiconductor element light source by 1st Embodiment of this invention. It is the enlarged view which showed the probe and light source unit of the photoacoustic imaging device by 2nd Embodiment of this invention. It is the enlarged view which showed the probe and light source unit of the photoacoustic imaging device by 3rd Embodiment of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings.

[First Embodiment]
(Configuration of photoacoustic imaging device)
First, the configuration of the photoacoustic imaging apparatus 100 according to the first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the photoacoustic imaging apparatus 100 according to the first embodiment of the present invention includes a pair of light source units 1, a probe 2, and an apparatus main body 3. The photoacoustic imaging apparatus 100 is configured to image the detection target Q based on the acoustic wave AW detected from the detection target Q. Further, the apparatus main body 3 and the pair of light source units 1 are connected via wirings 91a and 91b. Further, the apparatus main body 3 and the probe 2 are connected via a wiring 92. The apparatus main body 3 is configured to be able to output electric power, control signals, and the like to the pair of light source units 1 and the probe 2 via these wirings 91a, 91b and 92. Each of the pair of light source units 1 includes a light source unit 10. The probe 2 includes a detection unit 20.

  The photoacoustic imaging apparatus 100 is configured to emit light from the light source unit 10 (an optical semiconductor element light source 10a described later) toward the human body P. In addition, the photoacoustic imaging apparatus 100 is configured to detect the acoustic wave AW generated from the detection target Q in the human body P by the probe 2 by being irradiated with light. The human body P is an example of the “subject” in the claims.

  Here, in the first embodiment, the light source unit 10 (an optical semiconductor element light source 10a to be described later) uses light of 50% of the maximum intensity (the strongest intensity among the emitted light) as the center of the detection unit 20. It is configured to irradiate a region (for example, dermis region) in the vicinity of the surface of the detection object Q immediately below. Details will be described later. The dermis is one element constituting human skin. The dermis is placed inside the epidermis, which is placed on the outermost side of the skin, and contains many capillaries. In addition, the light source unit 10 is configured to be able to detect, for example, melanoma as a detection target Q formed on the skin by light irradiated to the dermis region.

  In the following description, as shown in FIG. 3, the direction from the probe 2 toward the detection target Q (see FIG. 2) to be imaged is a detection direction (A1 direction). As shown in FIG. 4, the probe 2 and the light source unit 1 have an elongated shape extending in a predetermined direction (referred to as a depth direction (B direction)) orthogonal to the detection direction (A1 direction). The detection unit 20 and the light source unit 10 (an optical semiconductor element light source 10a described later) are in a predetermined direction (referred to as a lateral direction (C direction)) orthogonal to the detection direction (A1 direction) and the depth direction (B direction). They are arranged side by side. For convenience of explanation, illustration of the human body P (detection target Q) is omitted in FIG.

  Each of the pair of light source units 1 is detachably attached to an outer surface 21a of a probe 2 (probe main body 21 described later). The pair of light source units 1 are attached to both sides of the probe 2 so as to sandwich the probe 2 in the C direction.

  The light source unit 1 includes a light source unit 10 and a light source body 11.

  The light source body 11 is configured to be fixedly attachable to the probe 2 via an attachment member (not shown). In addition, a light source substrate 10b (to be described later) of the light source unit 10 is installed in the vicinity of the end of the light source body 11 in the detection direction (A1 direction). The light source body 11 contains a drive circuit (not shown) for driving the light source unit 10.

  The light source unit 10 is configured to emit light for imaging toward the human body P. The light source unit 10 includes an optical semiconductor element light source 10a and a light source substrate 10b. The optical semiconductor element light source 10a is sealed with a sealing resin. Further, the end surface on the detection direction side (A1 direction side) of the sealing resin constitutes the light emission surface 10c.

  The optical semiconductor element light source 10a is configured to generate light having a predetermined wavelength in an infrared region suitable for imaging the human body P (for example, light having a center wavelength of about 700 nm to about 1000 nm). As such an optical semiconductor element light source 10a, for example, a light emitting diode element (LED element), a semiconductor laser element, or an organic light emitting diode element can be used. In addition, the orientation characteristic of a light emitting diode (LED) is shown in FIG. The light emitting diode is configured such that the relative intensity becomes the largest at a position where the orientation angle is 0 degree (front of the light emission direction), and the relative intensity gradually decreases as the orientation angle becomes larger (smaller).

  For example, the optical semiconductor element light source 10a has an orientation angle of 120 degrees. The orientation angle is an angular range in which light of 50% or more of the maximum intensity can be emitted. In short, the orientation angle is a so-called 1/2 beam angle.

  The light having the maximum intensity (100%) is emitted in the direction immediately below the center of the optical semiconductor element light source 10a. Hereinafter, the direction in which light having the maximum intensity (100%) is emitted is defined as the first direction. The direction in which 50% of the maximum intensity of light is emitted is defined as the second direction. Further, since the orientation angle is 120 degrees (an example), the angle formed by the first direction and the second direction is 60 degrees, which is half the orientation angle.

  As shown in FIG. 4, a plurality of optical semiconductor element light sources 10a are provided. The optical semiconductor element light sources 10a are arranged in a row on the light source substrate 10b in a plan view (viewed from the A1 direction side). Specifically, the optical semiconductor element light source 10a has a light source substrate so that there are three rows in the horizontal direction (C direction) and 14 rows in the depth direction (B direction) in which the detection unit 20 and the light source unit 10 are arranged in plan view. It is arranged (mounted) on 10b.

  As shown in FIG. 2, the probe 2 includes a detection unit 20 and a probe main body 21.

  The probe main body 21 is a housing portion that is gripped by the user when in use, and is configured such that the light source unit 1 (light source unit 10) is fixedly attached via an attachment member (not shown). A detection unit 20 is installed at an end of the probe body 21 in the detection direction (A1 direction).

  The detection unit 20 is configured to detect an acoustic wave AW generated from the detection object Q. The detection unit 20 is configured to output a detection signal of the detected acoustic wave AW to the apparatus main body 3 (a control unit 30 described later) via the wiring 92. The detection unit 20 includes an ultrasonic transducer 20a and an acoustic lens 20b.

  The ultrasonic transducer 20a is disposed on the opposite side of the detection direction (A1 direction) with respect to the acoustic lens 20b. Also, a plurality of ultrasonic transducers 20a are provided as shown in FIG. In addition, the ultrasonic transducers 20a are arranged in rows arranged in the depth direction (B direction) in a state of being in contact with the acoustic lens 20b. The ultrasonic transducer 20a is configured to detect the acoustic wave AW by receiving and vibrating the acoustic wave AW generated from the detection target Q.

  As shown in FIG. 3, the acoustic lens 20b has a bow shape that is curved so as to protrude in the detection direction (A1 direction). With this shape, the acoustic lens 20b is configured to be able to focus the acoustic wave AW from the detection object Q onto the ultrasonic transducer 20a. The acoustic lens 20b includes a reflective layer 20c that reflects the light from the optical semiconductor element light source 10a and transmits the acoustic wave AW. The reflective layer 20c is provided on the surface in the detection direction (A1 direction) side of the acoustic lens 20b, and covers the ultrasonic transducer 20a from the detection direction (A1 direction) side. The reflective layer 20c is formed by coating a metal such as aluminum, gold, or silver. Further, the inner part of the reflective layer 20c of the acoustic lens 20b is formed of a material containing silicon resin or the like. The reflective layer 20c is an example of the “reflecting part” in the claims.

  As shown in FIG. 3, the detection unit 20 and the optical semiconductor element light source 10a are arranged at the ends (A1 direction side) where the light is emitted from the optical semiconductor element light source 10a of the detection unit 20 and the light source unit 10, respectively. It arrange | positions on the same plane F extended in a horizontal direction (C direction). In short, the vertex N1 of the detection unit 20 and the light emission surface 10c of the light source unit 10 are arranged on the plane F, respectively.

  The apparatus body 3 includes a control unit 30 and a display unit 31 as shown in FIG.

  The control unit 30 is configured to control the emission of light from the optical semiconductor element light source 10a. In addition, the control unit 30 is configured to generate a photoacoustic wave image of the detection target Q based on the detection signal output from the detection unit 20.

  The display unit 31 is configured by a screen such as a general liquid crystal system. The display unit 31 is configured to display the photoacoustic wave image generated by the control unit 30 on this screen.

(Arrangement of light source part with respect to detection part)
Next, the arrangement of the light source unit 10 with respect to the detection unit 20 will be described with reference to FIG.

  First, an angle formed by the plane F and the light emitting surface 10c that emits light from the optical semiconductor element light source 10a is α. In the first embodiment, since the plane F and the light emitting surface 10c are on the same plane, α is 0 degree. Therefore, α is not shown in FIG. 3 (see FIG. 6 of the second embodiment for α). In addition, an angle formed between the first direction and the second direction is β (60 degrees which is half of the orientation angle). Further, in the horizontal direction (C direction), from directly below the center of the detection unit 20 (indicated by a one-dot chain line passing through the detection unit 20) to an end (point N2) on the detection unit 20 side of the light source unit 10 (light emission surface 10c). Let X be the distance. The width of the light exit surface 10c of the light source unit 10 is L.

  The light source part 10 is arrange | positioned in the position which satisfy | fills the following formula | equation (1) which shows the irradiation depth of the light to the human body P. FIG.

  {X / (tan (α + β))} − L × sin α ≦ 10.0 (mm) (1)

  {X / (tan (α + β))} in the above expression (1) is the light source 10 (light emitting surface 10c) end (point N2) on the detection unit 20 side and light having an intensity of 50% of the maximum intensity. The distance (Y) in the detection direction (A1 direction) from the shallowest position (point N3) immediately below the center of the detection unit 20 irradiated with. L × sin α is a distance in the detection direction (A1 direction) between the end (point N2) on the detection unit 20 side of the light source unit 10 (light emission surface 10c) and the plane F (in the first embodiment, L Xsin α = 0).

  Therefore, the light source unit 10 is disposed at a position where X≈6.93 or less. As a result, the photoacoustic imaging apparatus 100 applies light to the detection target Q in the region near the surface of the detection target Q at a depth (indicated by Y) shallower than 10.0 (mm) immediately below the center of the detection unit 20. It is comprised so that it can irradiate. More preferably, the photoacoustic imaging apparatus 100 is a detection object in a region near the surface of the detection object Q at a depth (indicated by Y) shallower than 4.0 (mm) directly below the center of the detection unit 20. It is preferable that Q be configured to be able to irradiate light.

(Effect of 1st Embodiment)
In the first embodiment, the following effects can be obtained.

  In the first embodiment, as described above, the light source unit 10 (optical semiconductor element light source 10a) is arranged so as to be aligned with the detection unit 20, and light having an intensity of 50% or more of the maximum intensity is the center of the detection unit 20. It arrange | positions so that it may irradiate to the area | region of the surface vicinity of the detection object directly under. Accordingly, light is emitted from the optical semiconductor element light source 10a such as a light emitting diode element having a relatively wide orientation angle. Therefore, when the optical semiconductor element light source 10a is arranged so as to be aligned with the detection unit 20, the light guide plate Without passing through the light, it becomes possible to irradiate light having an intensity of 50% or more of the maximum intensity to a region in the vicinity of the surface of the detection target immediately below the center of the detection unit 20. As a result, it is possible to irradiate light at a shallow position directly below the center of the detection unit 20 with a simple device configuration without providing a light guide plate.

In the first embodiment, as described above, the light source unit 10 and the detection unit 20 are arranged on the same plane extending in the lateral direction in which the optical semiconductor element light source 10a (light source unit 10) and the detection unit 20 are aligned. The angle between the light emitting surface 10c that emits light from the optical semiconductor element light source 10a (light source unit 10) and the plane is α, and light having the maximum intensity is emitted from the optical semiconductor element light source 10a (light source unit 10). An angle between one direction and a second direction in which light having an intensity of 50% of the maximum intensity is emitted from the optical semiconductor element light source 10a (light source unit 10) is β, and the light source from directly below the center of the detection unit 20 in the lateral direction The distance to the end on the detection unit 20 side of the unit 10 is X, the width of the light emitting surface 10c of the light source unit 10 is L, and the light source unit 10 satisfies the following expression indicating the irradiation depth of light to the human body P Place in position.
{X / (tan (α + β))} − L × sin α ≦ 10.0 (mm)
Thereby, by arranging the light source unit 10 with respect to the detection unit 20 so as to satisfy the above formula, the light source unit 10 can be easily arranged at a position where the irradiation depth is 10.0 mm or less immediately below the center of the detection unit. Can do.

  In the first embodiment, as described above, the light source unit 10 is provided with a plurality of optical semiconductor element light sources 10a, and the plurality of optical semiconductor element light sources 10a are arranged in a row in plan view. Thereby, compared with the case of using an optical fiber in which light must be diffused by the light guide plate and the amount of light is not stable, according to the present invention, a stable intensity can be obtained from a wide range along the columnar arrangement direction. Light can be irradiated directly under the center of the detection unit 20.

  Moreover, in 1st Embodiment, as mentioned above, the acoustic lens 20b which can converge an acoustic wave to the detection part 20 is provided in the detection part 20, and the optical lens 20b from the optical semiconductor element light source 10a (light source part 10) is provided. The reflection part which reflects the light of this and permeate | transmits an acoustic wave is provided. Thereby, since the light from the optical semiconductor element light source 10a can be reflected by the reflection portion, the light is absorbed by the acoustic lens 20b, and artifacts due to generation of photoacoustic waves from the acoustic lens 20b are suppressed. be able to. In particular, when the optical semiconductor element light source 10a is brought close to the detection unit 20, the amount of light applied to the acoustic lens 20b increases, and thus artifacts caused by generation of photoacoustic waves from the acoustic lens 20b are caused. It can be effectively suppressed.

  In the first embodiment, as described above, the probe main body 21 provided with the detection unit 20 and the light source unit 1 provided with the light source unit 10 are further provided, and the light source unit 1 is connected to the outer side surface 21 a of the probe main body 21. Removably attach to. Thereby, since the light source unit 1 including the optical semiconductor element light source 10a is detachably attached to the probe main body 21, the position adjustment of the light source unit 10 with respect to the detection unit 20 can be easily performed.

  In the first embodiment, as described above, the optical semiconductor element light source 10a of the light source unit 10 is one of a light emitting diode element, a semiconductor laser element, and an organic light emitting diode element. Thereby, since the light emitting diode element, the semiconductor laser element, and the organic light emitting diode element are light sources that can emit pulses with a relatively simple driving mechanism, it is possible to suppress an increase in the size of the light source unit 10. . As a result, it is possible to suppress the apparatus from becoming large.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIGS. 1 and 6. In the second embodiment, unlike the first embodiment in which the light emitting surface 10c (light source unit 10) is arranged on the same plane as the plane F, the light emitting surface 210c (light source unit 210) is inclined with respect to the plane F. An example will be described. In addition, the same structure as the said 1st Embodiment attaches | subjects and shows the same code | symbol as 1st Embodiment, and abbreviate | omits description. Further, for convenience of explanation, in FIG. 6, the human body P (detection target Q) is not shown.

  As shown in FIG. 6, in the light source unit 201 of the photoacoustic imaging apparatus 200 (see FIG. 1) according to the second embodiment, the light exit surface 210 c of the light source unit 210 is light from the light source unit 210 on the detection unit 20 side. Is inclined by an angle α with respect to the plane F.

  The end of the light source unit 210 on the side that emits light from the optical semiconductor element light source 10a (A1 direction side) is disposed on the plane F. In short, the end (point O) of the light emitting surface 210c on the side away from the detection unit 20 is disposed on the plane F.

  The light source part 210 is arrange | positioned in the position which satisfy | fills the above Formula (1) which shows the irradiation depth of the light to the human body P. FIG.

  In the above formula (1), {X / (tan (α + β))} indicates a line segment N2-N4. Further, L × sin α in the above formula (1) indicates a line segment N2-N5.

  As an example, a case where α = 5.0 degrees and L = 10 mm will be described. In this case, the light source unit 210 is disposed at a position where X = (4-sin (5 °)) × tan (65 °) ≈8.39 or less.

(Effect of 2nd Embodiment)
In the second embodiment, the following effects can be obtained.

  In the second embodiment, as described above, the light source unit 210 is arranged so as to be aligned with the detection unit 20, and light having an intensity of 50% or more of the maximum intensity is the surface of the detection target immediately below the center of the detection unit 20. It arrange | positions so that a near area | region may be irradiated. Thereby, light can be irradiated to a shallow position directly under the center of the detection unit 20 with a simple device configuration without providing a light guide plate.

(Third embodiment)
Next, a third embodiment will be described with reference to FIGS. 1 and 7. In the third embodiment, unlike the first embodiment in which the optical semiconductor element light source 10a provided near the tip of the light source unit 10 emits light and irradiates light, an example of irradiating light guided by the optical fiber 310b. Will be described. In addition, the same structure as the said 1st Embodiment attaches | subjects and shows the same code | symbol as 1st Embodiment, and abbreviate | omits description. For convenience of explanation, the human body P (detection target Q) is not shown in FIG.

  As shown in FIG. 7, in the light source unit 301 of the photoacoustic imaging apparatus 300 (refer FIG. 1) by 3rd Embodiment, the light source part 310 contains the laser light source 310a light-guided by the optical fiber 310b.

  A plurality of laser light sources 310a are provided. In addition, the plurality of laser light sources 310a as a whole have their light emitting end portions directed radially so that light is emitted with a predetermined orientation angle.

(Effect of the third embodiment)
In the third embodiment, the following effects can be obtained.

  In the third embodiment, as in the first embodiment, the light source unit 310 is arranged so as to be aligned with the detection unit 20, and light having an intensity of 50% or more of the maximum intensity is detected immediately below the center of the detection unit 20. It arrange | positions so that the area | region of the surface vicinity of a target object may be irradiated. Thereby, light can be irradiated to a shallow position directly under the center of the detection unit 20 with a simple device configuration without providing a light guide plate.

  Further, in the third embodiment, as described above, the light source unit 310 is provided with the laser light source 310a that guides light using the optical fiber 310b. Thereby, relatively strong light can be guided and irradiated by the optical fiber 310b. Further, by adjusting the direction of the laser light source, it is possible to easily irradiate light at a shallow position directly below the center of the detection unit 20.

[Modification]
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first to third embodiments, the example in which the light from the optical semiconductor element light source is reflected by the reflective layer formed by the coding as an example of the reflecting portion of the present invention is shown, but the present invention is not limited to this. Absent. In the present invention, the light from the optical semiconductor element light source may be reflected by a configuration other than the reflective layer, as long as it is possible to suppress light from being absorbed by the acoustic lens due to reflection. For example, the light from the optical semiconductor element light source may be reflected by a plate member made of metal such as gold as the reflecting portion of the present invention.

  In the first and second embodiments, the example in which the optical semiconductor element light sources are arranged in three rows extending in the depth direction is shown, but the present invention is not limited to this. In the present invention, the optical semiconductor element light sources may be arranged in the number of rows of 1, 2, 4 or more extending in the depth direction.

  In the first to third embodiments, the example in which the optical semiconductor element light source is arranged so as to irradiate light having an intensity of 50% of the maximum intensity to an area immediately below the center of the detection unit is shown. It is not limited to this. In the present invention, for example, the optical semiconductor element light source may be arranged so as to irradiate light having an intensity of 60% of the maximum intensity of 50% or more of the maximum intensity to an area immediately below the center of the detection unit. In addition, the above formula (1) may not be satisfied as long as light having an intensity of 50% or more can be applied to the region immediately below the center of the detection unit.

  Moreover, in the said 1st-3rd embodiment, although the example which set the orientation angle from a light source part to 120 degree | times was shown, this invention is not limited to this. In the present invention, for example, the orientation angle of the optical semiconductor element light source may be set to 100 degrees of 120 degrees or less, or 150 degrees larger than 120 degrees.

  Moreover, in the said 1st-3rd embodiment, although the example which comprised the light source unit so that attachment or detachment was possible was shown, this invention is not limited to this. In the present invention, the light source unit and the probe main body may be configured integrally.

100, 200, 300 Photoacoustic imaging apparatus 1, 201, 301 Light source unit 10, 210, 310 Light source unit 10a Optical semiconductor element light source 10c, 210c Light exit surface 20 Detection unit 20b Acoustic lens 20c Reflective layer (reflection unit)
21 probe body 21a outer surface 310b optical fiber P human body (subject)
Q Object to be detected

Claims (3)

An ultrasonic transducer for detecting an acoustic wave generated from a detection target to be imaged in a subject, and an arcuate shape curved so as to protrude in a detection direction toward the detection target, A detection unit having an acoustic lens capable of focusing an acoustic wave on the ultrasonic transducer ;
A light source unit arranged in a horizontal direction orthogonal to a detection direction from the detection unit toward the detection target,
The light source unit includes a plurality of light emitting diode elements arranged in a row in a depth direction orthogonal to the lateral direction on a light emitting surface that emits light,
The apex of the acoustic lens and the end of the light source part on the side away from the detection part of the light emitting part are respectively disposed on the same plane including the lateral direction and the depth direction.
The angle formed by the light emitting surface and the plane is α, the first direction in which light with the maximum intensity is emitted from the light source unit, and the second direction in which light with 50% of the maximum intensity is emitted from the light source unit. Β is the angle formed with the direction, X is the distance from directly below the center of the detection unit to the end of the light source unit on the detection unit side, and L is the width of the light emitting surface of the light source unit. ,
The light source unit is the following equation indicating the irradiation depth of light on the subject.
{X / (tan (α + β))} − L × sin α ≦ 10.0 (mm)
The photoacoustic imaging device arrange | positioned in the position which satisfy | fills. The photoacoustic imaging apparatus according to claim 1, wherein in the detection unit , the acoustic lens includes a reflection unit that reflects light from the light source unit and transmits acoustic waves. A probe main body provided with the detection unit; and a light source unit provided with the light source unit,
The photoacoustic imaging apparatus according to claim 1, wherein the light source unit is detachably attached to an outer surface of the probe main body.

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