JP4791395B2 - Medical imaging device - Google Patents

Description

  The present invention relates to a medical imaging apparatus, and more particularly to a technique for illuminating and imaging an affected area.

  Japanese Patent Application Laid-Open No. H10-228688 discloses an apparatus that takes an image while irradiating an affected area such as the oral cavity.

  Patent Document 1 discloses a technique in which an LED (Light Emitting Diode) is arranged around an imaging unit, and the irradiated affected part is imaged by the imaging unit while irradiating the affected part with the LED.

JP-A-2004-237081

  However, in patent document 1, since it is the structure which irradiates the affected part with the light from LED as it is, when LED and the affected part are comparatively far away, an affected part cannot be irradiated with appropriate illumination intensity.

  Here, for example, if a large number of LEDs are integrated at a high density, a relatively bright illuminance can be obtained in the affected area. However, in this case, it is an important problem how to match the irradiation range and the imaging range due to the restriction of the installation locations of a large number of LEDs and the imaging means.

  Therefore, an object of the present invention is to obtain an appropriate illuminance even at an affected part away from a light source unit and to make the irradiation range and the imaging range coincide as much as possible.

In order to solve the above problem, a medical imaging apparatus according to a first aspect is a medical imaging apparatus that irradiates an affected area with light and images the affected area, and is irradiated with a light source and the light source a condensing part for condensing light, and an imaging unit for imaging the light condensed by the condensing part in the diseased part, it is between the condensing section and the imaging section, the current An aperture provided in the vicinity of the beam waist of the optical part, which restricts the passage of the light collected by the condensing part, and the reflected light from the affected part is received via the imaging part and the aperture, and And an imaging unit that images the affected area.

  As in the second aspect, the apparatus may further include a movable arm that is movable, and a frame that fixes the light source unit, the light collecting unit, the imaging unit, and the aperture to the distal end of the movable arm. .

  Further, as in the third aspect, the light source unit may include any one of a light emitting diode, a halogen sphere, a krypton sphere, and a semiconductor laser as a light emitting element.

  Further, as in the fourth aspect, the light source unit includes a plurality of light emitting elements, and the light collecting unit includes a collimating lens provided on each light emitting surface of each of the light emitting elements, and a substantially central part. A condensing lens that condenses each light from each of the collimating lenses, and the imaging unit reflects reflected light from the affected part of the condensing lens. Light may be received through the hole.

  Further, as in the fifth aspect, the plurality of light emitting elements may be arranged in a substantially annular shape.

  In these cases, as in the sixth aspect, the light emitting element may be a light emitting diode.

Further, as in the seventh aspect, the aperture may have a substantially rectangular opening.

Further, as in the eighth aspect, the imaging unit may be disposed on a central axis of the light collecting unit and the imaging unit, and may have a zoom mechanism unit.

According to the medical imaging apparatus according to the first aspect, the light source unit, the light collecting unit that collects the light emitted from the light source unit, and the light collected by the light collecting unit is imaged on the affected part. And an aperture that is provided between the light collecting unit and the image forming unit and in the vicinity of a beam waist of the light collecting unit, and restricts passage of light collected by the light collecting unit. Therefore, appropriate illuminance can be obtained even in the affected part away from the light source part. In addition, since the imaging unit that receives the reflected light from the affected part through the imaging unit and the aperture and images the affected part is provided, the irradiation range and the imaging range can be matched. Further, when the affected part is not photographed (not used as a photographing device), it can be used as a medical lighting device. Further, the light from the light source can be efficiently limited, and the influence of the non-uniformity of the light source can be reduced to make the light uniform.

  In addition, according to the second aspect, the light source unit, the condensing unit, the imaging unit, and the aperture can be movably supported, and the medical imaging apparatus is appropriately moved to efficiently irradiate a desired irradiation site with illumination light. And a desired imaging region can be observed from the front.

  According to the fourth aspect, the condensing part is formed in a substantially annular shape having a collimating lens provided on each light emitting surface of each light emitting element and a hole in a substantially central part, and each collimating lens Therefore, the light from each light emitting element can be condensed efficiently. In addition, since the imaging unit receives the reflected light from the affected part through the hole of the condenser lens, the center of the irradiation range from the light source and the center of the imaging range can be made substantially the same. Furthermore, it is possible to eliminate the influence of the condensing unit when taking an image.

  Moreover, according to the 5th aspect, an affected part can be illuminated brightly with the light from the several light emitting element arrange | positioned cyclically | annularly.

  According to the sixth aspect, since the light emitting element is a light emitting diode, power consumption and heat generation can be reduced.

According to the 7th aspect, it is suitable for illuminating only the affected part, such as an oral cavity.

According to the eighth aspect, it is possible to reduce or enlarge the imaging range while keeping the center of the illumination range constant.

<First Embodiment>
Hereinafter, the medical imaging device according to the first embodiment will be described.

  1 is a schematic cross-sectional view showing a medical imaging apparatus, and FIG. 2 is a cross-sectional view taken along line II-II in FIG.

  This medical imaging apparatus 10 is used for, for example, dentistry, and is used to irradiate a patient's oral cavity (affected area) P and image the affected area P.

<Basic configuration of medical imaging device>
The medical imaging apparatus 10 includes a light source unit 14, a light collecting unit 20, an aperture 30, an imaging unit 40, and an imaging unit 50.

  The light source unit 14, the condensing unit 20, the aperture 30, and the imaging unit 40 are disposed in the cylinder 12 in that order along the axial direction of the cylinder 12. The imaging unit 50 is disposed at one end of the cylinder 12. The central axis of the cylindrical body 12 is a reference axis that also serves as the central axis of the light collecting unit 20, the imaging unit 40, the imaging unit 50, and the like. Moreover, the cylinder 12 may be cylindrical or rectangular.

  The light source unit 14 emits light, and here has a plurality of light emitting elements 14a.

  Each of the light emitting elements 14a is arranged in an annular shape around the central axis of the cylindrical body 12 (see FIG. 2). An LED (light emitting diode) is used as the light emitting element 14a. However, the light emitting element 14a is not limited to an LED, and a halogen sphere, a krypton sphere, a semiconductor laser, or the like may be used. Further, the arrangement and the number of the light emitting elements 14a are not limited to the example shown in FIG. 2, and the arrangement and the number for obtaining the illuminance required in the affected part P may be appropriately selected. For example, two on the left and two on the center axis of the cylinder 12 may be provided. Moreover, you may arrange | position in the cyclic | annular form more than double centering | focusing on the central axis of the cylinder 12. FIG. That is, the light emitting element 14a may be provided at a position that does not prevent the reflected light from the affected part P from entering the imaging element 54, that is, at the outer periphery of the optical path of the reflected light.

  The condensing unit 20 is an optical element that condenses the irradiation light from the light source unit 14. Here, the condensing part 20 has the collimating lens 22 and the condensing lens 24 which were provided in each light emitting element 14a.

  Each collimating lens 22 is disposed on the light emitting surface side of each light emitting element 14a. The collimating lens 22 may be physically separated from each light emitting element 14a or may be integrally formed with the light emitting element 14a. In addition, when using the light emitting element 14a (for example, LED etc. with which the collimating lens was molded in the light emission surface) which emits substantially parallel light, the collimating lens 22 may be abbreviate | omitted.

  The condenser lens 24 is disposed inside the cylinder 12 by a condenser lens holder 241 at a predetermined distance from the collimator lens 22 along the axial direction of the cylinder. It is an optical element that collects the light from. As such a condensing lens 24, a condenser lens using a convex lens, a Fresnel lens, or the like is used. In FIG. 1, the condensing lens 24 is shown as a plano-convex lens, but may be a biconvex lens or the like as long as desired condensing light is obtained. Further, the condensing lens 24 may be configured by combining a plurality of lenses.

  Further, a hole 26 is formed in a substantially central portion of the condenser lens 24, and the overall shape is formed in a substantially annular shape. The hole 26 is formed at a position that avoids an optical path through which reflected light from the affected part P enters the imaging unit 50. As long as the shape avoids such an optical path, the hole 26 may not be substantially circular, but may be substantially elliptical or rectangular. The reflected light from the affected area P is incident on the imaging section 50 without being refracted by the condenser lens 24.

  The image forming unit 40 is an optical element that forms an image on the affected part P with the light collected by the light collecting unit 20. Here, the imaging unit 40 is configured by a biconvex lens and is provided at the other end of the cylindrical body 12. However, the imaging unit 40 may be configured with a Fresnel lens or a plano-convex lens, or may be configured by combining a plurality of lenses.

An aperture 30 is provided between the imaging unit 40 and the condenser lens 24 inside the cylindrical body 12, and is fixed by a condenser lens holder 241 and an aperture holder 301. The aperture 30 is a flat plate member, and a rectangular opening 32 is formed at a substantially central portion thereof. The aperture 30 has a role of restricting the passage of light collected by the light collecting unit 20. Since the shape of the opening 32 is determined in consideration of the range in which the affected part P is illuminated, it is not necessarily limited to a rectangular shape. In addition, as a dental medical lighting device, it is preferable that only a range (for example, a range of 80 × 150 mm) slightly wider than the oral cavity that is the affected part P is set as the illumination range. It is formed in a rectangular shape. The aperture 30 can be obtained by forming the opening 32 in a plate material such as a metal plate. However, a mechanical mechanism is provided so that the shape of the opening 32 can be changed, or a liquid crystal aperture is employed. Alternatively, the aperture 30 itself may be exchangeable with one having various opening 32 shapes.

  The imaging unit 50 is configured to receive reflected light from the affected part P via the imaging unit 40 and the aperture 30 and to image the affected part P.

More specifically, the imaging unit 50 is disposed on the extension of the central axis of the cylindrical body 12 and on the opposite side of the condenser lens 24 with respect to the light source unit 14. That is, the imaging unit 50 is provided on the side opposite to the irradiation direction by the light source unit 14. Imaging unit 50 includes a camera tube 52, an imaging element 5 4 fixed to the camera tube portion 52, an imaging lens 56 and a zoom mechanism which is disposed in front of the imaging surface 54a of the imaging element 5 4 Part 58.

Imaging element 5 4 has a CCD (Charge Coupled Device) or the like. An imaging lens 56 has optical characteristics for imaging light from the affected part P on the imaging plane 54a of the imaging element 5 4. The zoom mechanism unit 58 has a zoom lens that can be moved manually or by an actuator such as a motor along the central axis of the camera tube unit 52, and has a function of enlarging and reducing the image of the irradiated affected part P. Yes. Of course, these imaging lens 56 and zoom lens may also be constituted by a plurality of lens groups. Incidentally, the imaging lens 56 by moving, it may be allowed a simple change in magnification to adjust the imaging element 5 4 in order to adjust the focus.

  Then, the reflected light from the affected part P in a predetermined range is irradiated from the imaging part 40 to the opening part 32 of the aperture 30, the hole part 26 of the condenser lens 24, the substantially central part of the annular light emitting element 14a, Further, the light enters the imaging surface 54 a via the zoom mechanism 58 and the imaging lens 56.

The positions of the imaging unit 40 and the aperture 30 may be moved along the central axis direction of the cylindrical body 12. In addition, the distance from the imaging unit 40 to the affected part P is preferably set to 400 to 900 mm in order to ensure a sufficient work space for the operator to treat the affected part P in the meantime.

<Optical characteristics of the device>
Next, the optical characteristics of this apparatus will be described with reference to the optical path shown in FIG. In FIG. 1, an optical path L1 indicates light irradiated to the affected area, and an optical path L2 indicates reflected light from the affected area.

  First, light emitted from each light emitting element 14 a provided at one end of the cylindrical body 12 becomes substantially parallel light by the collimator lens 22. Here, since the eight light emitting elements 14a are provided in a ring shape, substantially parallel light having a substantially cylindrical surface is emitted.

The substantially parallel light from each light emitting element 14 a is condensed at a predetermined position by the condenser lens 24. That is, in the medical imaging apparatus 10 according to the present embodiment, in order to collect the light from the light emitting element 14a that is a plurality of light sources at a predetermined position, each collimator lens 22 once creates substantially parallel light, thereby The light is condensed at a focal point shared by one condenser lens 24. Thereby, the light from the light emitting element 14a which is a some light source can be efficiently condensed. Note that, between the condenser lens 24 and the aperture 30 in FIG. 1, a range of light that enters the aperture 32 of the aperture 30 among light emitted from the condenser lens 24 is indicated by a straight line R.

  Next, the light collected by the condenser lens 24 is shielded by the aperture 30 except for the light passing through the opening 32. The position of the aperture 30 is preferably arranged in the vicinity of the beam waist of the condenser lens 24. This is because the light of the light source having the plurality of light emitting elements 14a is efficiently limited, the influence of non-uniformity is reduced, and the light is made uniform.

  The opening 32 of the aperture 30 has a substantially rectangular shape as described above, and the light that has passed through the aperture 30 is irradiated to the affected part P via the imaging unit 40. That is, in the present embodiment, it can be understood that a substantially rectangular light image formed by the aperture 30 forms an image on the affected part P by the image forming unit 40.

Further, when light at affected part P which is irradiated in a substantially rectangular shape for reflecting its reflected light is generally spread anti shines through the imaging unit 40 is imaged again to the opening 32 near the aperture 30. Then, the imaged light enters the imaging unit 50 through the hole 26 of the condenser lens 24. Reflected light, the imaging unit 50, is incident on the imaging surface 54a of the imaging element 5 4 through the zoom mechanism section 58 and the imaging lens 56. Thereby, the diseased part P in the image pickup element 5 4 is to be imaged.

In addition, when using this medical imaging device for dentistry, each of the above-described elements is set so that the range of the affected part P to be illuminated is, for example, 80 × 150 mm, and the distance from the imaging unit 40 to the affected part P is 400 to 900 mm. The size, optical characteristics, position, etc. are set.

According to the medical imaging apparatus 10 configured as described above, the light source unit 14 or RaTeru Isa light is condensed by the condenser 20, to limit the condenser light at the opening 32 of the aperture 30 Since the image is formed on the affected part P via the image forming part 40, a relatively bright appropriate illuminance suitable for treatment or the like can be obtained even in the affected part P away from the light source part 14. In addition, since the reflected light from the affected part P is received through the image forming part 40 and the opening 32 of the aperture 30 and the imaged part 50 is imaged, the irradiation range and the imaged range are matched. Can be made.

  In addition, the irradiation light from the light source unit 14 is applied to the affected part P through the imaging unit 40, and the reflected light from the affected part P also enters the imaging unit 50 through the imaging unit 40. For this reason, since the reflected light uses light passing through the vicinity of the optical axis of the imaging unit 40, the aberration and the like are relatively small, and a good captured image can be obtained.

  In addition, a hole 26 is formed at a substantially central portion of the condenser lens 24, and the imaging unit 50 receives reflected light from the affected part P through the hole 26. For this reason, it is possible to make the irradiation range of the light source unit 14 coincide with the center of the imaging range while eliminating the influence of the condenser lens 24 when imaging.

  Further, the affected area P can be illuminated brightly by the light emitting element 14a arranged in an annular shape. At the same time, a space for disposing the imaging unit 50 can be provided at a substantially central portion.

  Moreover, since LED is used as the light emitting element 14a, the calorific value in the light source part 14 can be decreased.

  Furthermore, since the zoom mechanism unit 58 is incorporated in the imaging unit 50, the imaging range can be reduced and enlarged while keeping the center of the illumination range constant.

Second Embodiment
Hereinafter, the medical imaging device according to the second embodiment will be described. FIG. 3 is a schematic side view showing the overall configuration of the medical imaging apparatus, FIG. 4 is a schematic perspective view showing the main part of the medical imaging apparatus, and FIG. 5 shows the main part of the medical imaging apparatus. FIG. 6 is a sectional view taken along line VI-VI in FIG.

  In addition to the medical imaging apparatus 10 described in the first embodiment, the medical imaging apparatus 110 further includes a movable arm 120, a light source unit 14, a condensing unit 20, an imaging unit 40, and the like. A frame body 130 for fixing the configuration including the aperture 30 to the distal end of the movable arm 120 is provided. The medical imaging apparatus 10 itself has the same configuration as that described in the first embodiment, and a description thereof will be omitted.

  The movable arm 120 is attached to the upper end portion of the support column 122 erected at a predetermined position, and can be maintained in a predetermined posture that is movable and bent in a bending manner by a configuration including a well-known link mechanism. It is configured.

  The frame body 130 is attached to the distal end portion of the movable arm 120 and holds the medical imaging apparatus 10 in the first embodiment. The frame 130 is provided with a handle 132 so that the operator can easily move the frame.

  In addition to the above, the medical imaging apparatus 110 includes a dental examination table 140, a gargle spit 142, a foot controller 144, and a display device 146.

  The dental examination table 140 is configured to be able to support the patient so that the posture can be freely changed and raised and lowered in accordance with an operation on the foot controller 144. In addition, a gargle spitton 142 and a support column 122 are provided adjacent to the dental examination table 140. The display device 146 includes a liquid crystal display device, a CRT (Cathode Ray Tube) display device, and the like. The display device 146 is attached in the middle of the column 122 and displays an image photographed by the medical photographing device 10.

  In such a medical imaging apparatus 110, the configuration including the light source unit 14, the condensing unit 20, the imaging unit 40, and the aperture 30 can be movably supported. For this reason, the operator can perform treatment work by arranging the medical imaging apparatus 10 in a fixed posture and a fixed position without holding the medical imaging apparatus 10 by hand.

<Modification>
As an application example of the medical imaging apparatus according to each of the embodiments, when an LED is used for the light emitting element 14a, a white LED and an LED having a wavelength of 400 ± 20 nm are incorporated, and the two are switched and turned on. May be configured to be possible. In dental diagnosis, it is known that when light having a wavelength of 400 ± 20 nm is irradiated into the oral cavity, a portion where tartar or plaque adheres emits red fluorescence. Further, it is also known that when a light having a wavelength of 400 ± 20 nm is irradiated into the oral cavity, an image useful for diagnosis of a carious portion can be obtained, so that a lesion can be easily detected. Therefore, by incorporating an LED with a wavelength of 400 ± 20 nm, in addition to the function of illuminating and imaging the affected part P, it is also possible to perform a dental diagnosis with an image taken while illuminating with light of a wavelength of 400 ± 20 nm. It becomes.

As another application example of the medical imaging apparatus according to each of the embodiments, when an LED is used for the light emitting element 14a, a white LED and an LED having a wavelength of 470 ± 20 nm are incorporated, and the two are switched and turned on. You may comprise so that it can do. In dental treatment, light having a wavelength of 470 ± 20 nm is used to photopolymerize the resin in the affected area P. Therefore, by further incorporating an LED having a wavelength of 470 ± 20 nm, in addition to the function of photographing while illuminating the affected area P, it is also possible to perform dental treatment with an image photographed while illuminating with light having a wavelength of 470 ± 20 nm. It becomes.

As another application example of the medical imaging apparatus according to each of the embodiments, when an LED is used for the light emitting element 14a, a white LED and an LED having a wavelength of 405 ± 20 nm are incorporated, and the two are switched and turned on. Or you may comprise so that it can light simultaneously. In the dental field, light having a wavelength of 405 ± 20 nm is also used for tooth bleaching. Therefore, by further incorporating an LED having a wavelength of 405 ± 20 nm, it is possible to bleach teeth with light having a wavelength of 405 ± 20 nm in addition to the function of photographing while illuminating the affected area P.

  In each of the above embodiments, the example used for irradiating the patient's oral cavity (affected part) P in dental practice has been described. However, the present invention is not limited to dentistry, and is used in other medical fields such as otolaryngology. It can also be used to irradiate and image an affected area such as the nose.

It is a schematic sectional drawing which shows the medical imaging device which concerns on 1st Embodiment. It is the II-II sectional view taken on the line of FIG. It is a schematic side view which shows the whole structure of the medical imaging device which concerns on 2nd Embodiment. It is a schematic perspective view which shows the principal part of a medical imaging device same as the above. It is a schematic plan view which shows the principal part of a medical imaging device same as the above. FIG. 6 is a sectional view taken along line VI-VI in FIG. 5.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Medical imaging device, 14 Light source part, 14a Light emitting element, 20 Condensing part, 22 Collimating lens, 24 Condensing lens, 26 Hole part, 30 Aperture, 32 Aperture part, 40 Imaging part, 50 Imaging part, 58 Zoom Mechanical part, 110 medical imaging device, 120 movable arm, 130 frame, 132 handle.

Claims (8)

A medical imaging device that irradiates an affected area with light and images the affected area,
A light source unit;
A light collecting unit that collects the light emitted from the light source unit;
An image forming unit that forms an image on the affected part of the light collected by the light collecting unit;
An aperture between the light condensing unit and the image forming unit, provided near the beam waist of the light condensing unit, and restricting the passage of light collected by the light condensing unit;
An imaging unit that receives the reflected light from the affected part through the imaging unit and the aperture and images the affected part; and
Medical imaging device with The medical imaging device according to claim 1,
A movable arm,
A medical imaging apparatus further comprising: a frame body that fixes the light source unit, the condensing unit, the imaging unit, and the aperture to a distal end of the movable arm. The medical imaging device according to claim 1 or 2,
The said light source part is a medical imaging device provided with any one of a light emitting diode, a halogen bulb, a krypton bulb, and a semiconductor laser as a light emitting element. The medical imaging device according to any one of claims 1 to 3,
The light source unit has a plurality of light emitting elements,
The condensing part is formed in a substantially annular shape having a collimating lens provided on each light emitting surface of each light emitting element and a hole in a substantially central part, and condenses each light from each collimating lens. A condenser lens,
The medical imaging device, wherein the imaging unit receives reflected light from the affected part through the hole of the condenser lens. The medical imaging device according to claim 4,
The medical imaging apparatus, wherein the plurality of light emitting elements are arranged in a substantially ring shape. The medical imaging device according to claim 4 or 5, wherein
The medical imaging apparatus, wherein the light emitting element is a light emitting diode. The medical imaging device according to any one of claims 1 to 6,
The aperture is a medical imaging apparatus having a substantially rectangular opening . The medical imaging device according to any one of claims 1 to 7,
The medical imaging apparatus , wherein the imaging unit is disposed on a central axis of the light collecting unit and the imaging unit and has a zoom mechanism unit .

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