Phototherapeutic apparatus

Abstract

To provide a phototherapeutic apparatus capable of preventing burns without reducing treatment effects even on the skin with a lentigo, body hair and the like.SOLUTION: A phototherapeutic apparatus comprises: a light irradiation part that applies a beam to the skin which is an irradiation region; a cooling part that cools the irradiation region when the beam is applied by the light irradiation part; a skin color information acquisition part that acquires skin color information on the irradiation region; and a cooling intensity adjustment part that adjusts cooling intensity of the cooling part on the basis of details of the acquired skin color information.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a phototherapy device. [Background technology]

[0002] Phototherapy devices are used to irradiate biological tissue with light rays for the purpose of treatment or to assist in treatment, such as promoting blood circulation and metabolism. Laser light, among other types of light rays, is widely used for these purposes because it can irradiate specific wavelengths with high power. In the laser classes in the laser safety standard JIS C 6802, when using high-power phototherapy devices with class 3 or higher for home medical care, compliance with class 1C is a mandatory requirement.

[0003] If the location and condition of the skin at a given location, which is the target tissue, and the degree of skin color, moles, age spots, and body hair are different, the amount of thermal energy absorbed by the skin will differ even if the laser light is irradiated with the same power and for the same time. In particular, in skin with moles or body hair, the amount of thermal energy absorbed is relatively large, and there is a possibility of burns. The main pigment components that determine the color of the skin are melanin and hemoglobin. Melanin is a black pigment, and the more melanin is contained in the skin, the darker the skin color will be. It is particularly abundant in pigmented areas such as moles and age spots. Hemoglobin is a red pigment contained in red blood cells in the blood, and the more blood flow the redder the skin will be. In inflammatory areas such as erythema, it is contained in large amounts due to increased blood. Therefore, it can be said that areas with a high amount of melanin and hemoglobin are likely to be burned.

[0004] A phototherapy device (Patent Document 1) is known that determines the irradiation conditions by determining the skin color and hair thickness at the irradiation site from a skin image taken by a camera in order to prevent burns caused by irradiation with laser light. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-11106 A Summary of the Invention [Problem to be solved by the invention]

[0006] The laser treatment device described in Patent Document 1 includes a skin color detection means having a detector for detecting the color of the skin to be irradiated with laser light, an adjustment means for an operator to adjust the settings of laser irradiation conditions, a storage means for storing the skin color detected by the skin color detection means and the irradiation conditions adjusted by the adjustment means in association with each other, and an irradiation condition setting means for automatically setting the irradiation conditions based on the skin color detected by the skin color detection means and the stored data of the storage means. Also, a hair detection means is provided for detecting the thickness of hair in the area to be irradiated with laser light, and the hair thickness detected by the hair detection means is stored in the storage means in association with the skin color and the irradiation conditions, and the irradiation conditions are automatically set by the irradiation condition setting means based on the detection results of the hair detection means and the skin color detection means and the stored data of the storage means. The irradiation energy (laser power and pulse irradiation time) is set as the irradiation condition according to the skin color and the thickness of the hair. That is, for skin with moles or body hair, the risk of burns is avoided by setting the irradiation energy low. On the other hand, the therapeutic effect depends on the irradiation energy that reaches the target tissue. Therefore, the configuration of Patent Document 1 may impair the therapeutic effect.

[0007] An object of the present invention is to provide a phototherapy device that can prevent burns without impairing the therapeutic effect even on skin that has moles, body hair, or the like. [Means for solving the problem]

[0008] The present invention provides the following phototherapy device. 1) A phototherapy device comprising a light irradiation unit that irradiates light rays toward skin, which is an irradiation site, a cooling unit that cools the irradiation site while the light rays are being irradiated by the light irradiation unit, a skin color information acquisition unit that acquires skin color information of the irradiation site, and a cooling intensity adjustment unit that adjusts the cooling intensity of the cooling unit based on the content of the acquired skin color information. 2) The phototherapy device according to 1) above, wherein the skin information acquisition unit is a skin color information acquisition unit that acquires color information of the skin of the irradiation area. 3) The phototherapy device according to 2) above, wherein the skin color information acquisition unit is a skin image acquisition unit that acquires a skin image of the irradiation site acquired from a camera built into the phototherapy device or an external camera. 4) The phototherapy device described in 3) above, characterized in that the cooling unit is a cooling fan, and the cooling intensity adjustment unit is a means for adjusting the air volume of the cooling fan based on color information of the skin of the irradiated area acquired by the skin image acquisition unit. 5) The phototherapy device described in 4) above, characterized in that the skin color information is a pixel value of a grayscale image of the irradiated area, or lightness L* and / or chromaticity a* of the L*a*b* color system of a color image, and the cooling intensity adjustment unit is a means for adjusting the air volume of the cooling fan based on the minimum pixel value in the grayscale image of the irradiated area, or the minimum L* value and / or maximum a* value in the color image. 6) The phototherapy device described in 5) above, further comprising a light emission control unit that determines whether or not to emit light from the irradiation unit based on color information of the skin of the irradiated area acquired by the skin image acquisition unit, and is characterized in that the output power of the light is maintained constant when the light is emitted. 7) The phototherapy device described in 6) above, characterized in that when the skin color information exceeds a relational threshold between the skin color information and the cooling air volume for burn prevention and risk reduction irradiation, the emission of light rays from the irradiation unit is prohibited. 8) The phototherapy device described in 3) above, further comprising a memory means for storing image information of the skin at the irradiation site, and characterized in that when the detected skin image information differs from the immediately previous stored skin image information, the airflow rate of the cooling fan is changed. Effect of the Invention

[0009] The phototherapy device of the present invention can control the cooling intensity based on the skin information of the irradiated area, while maintaining the output power of the irradiated light. This makes it possible to suppress the temperature rise of the skin caused by the irradiation of the light, and to prevent burns without reducing the irradiation energy of the light. Therefore, it is possible to prevent burns without compromising the therapeutic effect even on the skin of patients with dark skin or patients with moles or body hair at the irradiated area. [Brief description of the drawings]

[0010] [Figure 1] 1 is an external view showing an embodiment of a phototherapy device of the present invention. [Diagram 2] 4 is a flowchart showing the operation of the phototherapy device of the present invention. [Diagram 3] FIG. 1 is a block diagram showing an embodiment of a phototherapy device of the present invention. [Figure 4] FIG. 1 is a block diagram showing an embodiment of a phototherapy device of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The phototherapy device of the present invention will be described with reference to the drawings. Fig. 1 is a schematic view of the exterior of an embodiment of the phototherapy device of the present invention.

[0012] The phototherapy device 1 of the present invention comprises a probe 3 equipped with a light irradiation unit 6 that irradiates light toward the upper surface 19 of the skin, which is the irradiation site, a cooling unit 14 that cools the irradiation site when light is being irradiated by the light irradiation unit, a skin information acquisition unit that acquires information about the skin, which is the irradiation site, and a control unit 2 that has a cooling intensity adjustment unit that adjusts the cooling intensity of the cooling unit based on the content of the acquired skin information.

[0013] The light irradiation unit 6 includes a therapeutic light source. A power source may be built-in. The therapeutic light source may be a laser, an LED, a halogen lamp, a xenon lamp, or the like. The light irradiation unit 6 may include a light guide path such as an optical fiber to guide the light from the therapeutic light source to the irradiation site.

[0014] The control unit 2 includes a skin information acquisition unit that acquires information about the condition of the skin, which is the irradiated area, a cooling intensity adjustment unit that adjusts the cooling intensity of the cooling unit, and a light emission control unit that controls the light emission of the light irradiation unit. The control unit 2 and the light irradiation unit 6 are connected by a cable 4, and irradiation is started and ended in response to a signal from the control unit 2.

[0015] The cooling unit 14 uses an air-cooling type cooling means using a cooling fan, but various cooling means such as a Peltier element, or a water-cooling method using water or a refrigerant can be used. The cooling strength adjustment unit adjusts the cooling temperature and cooling speed, making it possible to suppress an increase in the skin temperature of the irradiated area.

[0016] The skin information acquisition unit is a means for acquiring information on the condition of the skin, which is the irradiated area, and is a means for acquiring skin color information such as skin color, the presence or absence of moles or body hair, and a means for acquiring information such as the moisture content of the skin, skin temperature, and the presence or absence of inflammation. The skin color information can be acquired by a means for measuring the amount of pigments such as melanin, hemoglobin, and carotene, which are factors related to the skin tone. For example, the skin color and erythema can be detected by using the spectral characteristics of the skin, such as the absorption of melanin and hemoglobin at 400 to 500 nm and the absorption of oxyhemoglobin at 500 to 600 nm, using a spectrometer. It is also possible to acquire an image of the skin at the irradiated area using a built-in camera or an external camera, or to use image data of the irradiated area acquired separately, and a skin image analysis can be performed based on such image data.

[0017] 3 and 4 show a detailed structure including the internal configuration of an embodiment of the phototherapy device of the present invention. The phototherapy device 1 of the present invention includes a control unit 2 and a probe 3 incorporating a light irradiation unit 6, and the control unit 2 and the probe 3 are electrically connected by a cable 4. The control unit 2 includes a skin image acquisition unit 22, a cooling air intensity adjustment unit 23, and a light emission control unit 21. Power is supplied from the control unit 2 to a housing 5 of the probe 3.

[0018] Skin image acquiring unit 22 has at least one processor, a storage unit, and peripheral circuits thereof. Skin image acquiring unit 22 captures a skin image from built-in camera 17 or an external device, stores the contents of color information of the skin image, and transmits the color information to cooling air intensity adjusting unit 23. The color information includes at least one of brightness information and chromaticity information. Skin image acquiring unit 22 may have an input / output unit, for example, a display unit such as a display, and an input interface such as an operation button or a touch panel.

[0019] Cooling air strength adjustment unit 23 has at least one processor, a storage unit, and their peripheral circuits, etc. Cooling air strength adjustment unit 23 controls the operation of cooling unit 14 based on the content of the color information of the skin image received from skin image acquisition unit 22 and the correspondence between the content of the color information of the skin image and the cooling strength that is stored in advance in the storage unit.

[0020] The light emission control unit 21 has at least one processor and its peripheral circuits, etc. The light emission control unit 21 receives a signal from the cooling airflow intensity adjustment unit 23 and controls the operation of the light irradiation unit 6.

[0021] The probe 3 has a cylindrical housing 5. The housing 5 has a light irradiation unit 6 disposed inside the housing. The part of the surface of the target site irradiated with light is called the irradiation field of the light.

[0022] Cooling unit 14 uses fan 15 as a cooling means, and the cooling strength is adjusted by controlling the volume of cooling air. An air intake 12 is provided on the side of the main body. An exhaust port 13 is provided on the side of the main body opposite to air intake 12. Exhaust port 13 is provided on the side near the front end of the main body, and air intake 12 is provided at a position farther away from the front end than exhaust port 13.

[0023] The probe 3 has a cooling unit that supplies cooling air to be sprayed into the main body from the air inlet 12. The cooling unit 14 has a fan 15 arranged adjacent to the side of the main body, and a duct 16 that connects the fan 15 and the air inlet 12. Therefore, air taken in by the rotation of the fan 15 is guided to the air inlet 12 via the duct 16. The power source may be built-in. The cooling air strength adjustment unit 23 is connected to the fan 15 through a cable. The cooling strength is adjusted by controlling the volume of the cooling air in response to a signal from the control unit 2.

[0024] The fan 15 is configured to generate an airflow in a direction away from the side of the main body. That is, the blade shape of the fan and the rotation direction of the fan are determined so as to generate such an airflow. The airflow in the direction away from the side of the main body removes heat from the surface of the main body, making it possible to cool the main body and, ultimately, the entire probe. The light irradiation unit 6 is equipped with a low-output laser as a light source for treatment.

[0025] Fig. 2 is a flow chart showing the operation of the phototherapy device 1. First, the skin image acquisition unit 22 receives the skin image data and acquires color information of each pixel. When capturing a skin image, in order to correct variations in scale and color tone due to differences in capturing conditions, a color chart for image correction may be placed near the irradiated area so that both the irradiated area and the color chart for image correction are captured. In this case, the image is opened in the image processing unit in the control unit, and the entire image is color-toned by clicking the white, black, or gray of the color chart for image correction in the image and inputting the level correction reference value.

[0026] The color information acquired by the skin image acquisition unit 22 can be, for example, pixel values ​​in the case of a grayscale image, and values ​​of lightness L* and chromaticity (hue + saturation) a* in the L*a*b* color system calculated from RGB values ​​in the case of a color image.

[0027] In a grayscale image, the darker the skin color, the darker the image will appear overall, and areas with moles, body hair, etc. will appear darker than their surroundings. The darker the image, the smaller the pixel value. Thus, the darker the skin color, the smaller the pixel value overall, and the pixel values ​​of pixels corresponding to areas with moles, body hair, etc. will be relatively smaller than their surroundings. In the case of a grayscale image, a mole, body hair, etc. is identified as a location where pixels having pixel values ​​below a specified value, or between the maximum value and a specified value, exist adjacently for a specified area or more. For skin color, it is desirable to use the most frequent pixel value.

[0028] In color images, the lightness L* of the L*a*b* color system can generally be used as an index of the degree of skin darkening, reflecting the amount of melanin, while the chromaticity a* can be used as an index of the degree of skin erythema and inflammation, reflecting the amount of hemoglobin. Since melanin absorbs light of a wide range of wavelengths, it is desirable to basically use the L* value to adjust the cooling air strength. When the wavelength of light is blue or green, the amount of light absorbed by the erythema or inflammation area is large, so it is desirable to adjust the cooling air strength using the a* value as well. The higher the amount of melanin, i.e., the higher the degree of skin darkening, the smaller the L* value, and the higher the amount of hemoglobin, i.e., the higher the degree of skin erythema and inflammation, the larger the a* value.

[0029] In the case of color images, a region where pixels having an L* value below a certain value, or between the maximum and a certain value, exist adjacently over a certain area or more is deemed to be a mole or body hair. Also, a region where pixels having an a* value above a certain value, or between the minimum and a certain value, exist adjacently over a certain area or more is deemed to be an erythema or inflammatory region. For skin color, the most frequent value of the L* value and / or the a* value is used.

[0030] In addition to the L*a*b* color system described above, there are various other methods for expressing skin color, such as the Munsell color system and the XYZ color system, which can be used instead of the L*a*b* color system. However, the L*a*b* color system is the most common method for expressing pigmentation such as moles and age spots.

[0031] The cooling air strength is set using the color information value of the location with the highest light absorption among the areas containing moles or body hair identified by the above-mentioned determination method. That is, in the case of a grayscale image, the minimum pixel value is preferable, and in the case of a color image, the minimum L* value and / or the maximum a* value is preferable. This makes it possible to set the cooling air strength according to the location with the highest risk of burn in the irradiation area. When the average value or mode value is used, there is a risk of underestimating the color intensity of localized moles or inflammation when the skin occupies the majority of the imaging area.

[0032] Cooling air intensity adjustment unit 23 receives color information from skin image acquisition unit 22, i.e., the minimum pixel value in the case of a grayscale image, and the minimum L* value and / or the maximum a* value in the case of a color image. A correspondence relationship between the pixel value, the L* value, and the a* value and the cooling air intensity value that reduces the risk of burns is stored in a memory unit of cooling air intensity adjustment unit 23. Cooling air intensity adjustment unit 23 sets the cooling air intensity based on the minimum pixel value, the minimum L* value, and / or the maximum a* value received from skin image acquisition unit 22, and the correspondence relationship between the pixel value, the L* value, and the a* value stored in the memory unit and the cooling air intensity value that reduces the risk of burns, and starts the fan.

[0033] The light emission control unit 21 receives a signal from the cooling air intensity adjustment unit 23 to start the fan 15, and allows light irradiation. If the pixel value or L* value and / or a* value received by the cooling air intensity adjustment unit 23 from the skin image acquisition unit 22 does not correspond to the pixel value, L* value, and a* value in the storage unit and the cooling air intensity value that reduces the burn risk, or if the corresponding relationship indicates that light irradiation is not allowed, the light emission is not allowed. If the light emission control unit 21 allows light irradiation, light irradiation from the light irradiation unit 6 is started in response to the start of the fan 15. The light emission control unit 21 and the light irradiation unit 6 maintain the output power of the light beam constant during the irradiation time. This prevents a decrease in the treatment effect due to a decrease in the output power.

[0034] By determining the cooling air strength as described above, a cooling air strength that reduces the risk of burns according to the skin color of the irradiated area can be set, making it possible to perform treatment safely.

[0035] As shown in Fig. 3, when the opening 18 at the tip of the housing 5 of the probe 3 is in close contact with the upper surface 19 of the skin, which is the area to be irradiated, the opening 18 is sealed by the upper surface 19 of the skin, or the distance between the opening 18 and the upper surface 19 of the skin is less than 12 mm, which corresponds to the width of one finger. This structure prevents the light beam from being irradiated to areas other than the target area, allowing the light beam to be irradiated more safely and appropriately.

[0036] 4 shows a case where the skin image acquisition unit includes a camera 17 built into the probe. The skin image acquisition unit 22 of the control unit 2 captures the skin image captured by the camera 17, stores the color information of the skin image, and transmits it to the cooling air intensity adjustment unit 23. The provision of the camera 17 in the phototherapy device 1 makes it possible to adjust the cooling air intensity before each treatment. This allows treatment to be performed at an appropriate cooling air intensity at all times in response to changes in the skin condition during the treatment period.

[0037] The skin image acquisition unit 22 may be equipped with a single camera or multiple cameras 17, 17' as shown in Fig. 4. When there are multiple irradiation sites or when the area of ​​the irradiation site is large, it may be difficult to capture the entire irradiation field with one camera. By providing multiple cameras, it becomes easier for the patient to capture the entire irradiation field without adjusting the position of the camera.

[0038] Instead of the built-in camera 17, it is also possible to provide a movable camera separately provided in the phototherapy device 1. By providing a movable camera instead of providing multiple cameras, it becomes easier for the patient to photograph the entire irradiation field without having to adjust the position of the camera.

[0039] The patient confirms that the markings applied in advance near the area to be irradiated are visible in the skin image, and then the skin image is captured. The skin image capture unit identifies the irradiation field based on the relative size and position coordinates of the markings, and obtains color information about the irradiation field.

[0040] When the skin image acquisition unit 22 includes the camera 17, it is preferable that the skin image acquisition unit 22 acquires time-series data of color information. The cooling air strength is determined during light irradiation, and if the cooling air strength set based on the minimum pixel value, the minimum L* value, and / or the maximum a* value received from the skin image acquisition unit 22, and the correspondence between the pixel value, the L* value, and the a* value in the storage unit and the cooling air strength value that reduces the risk of burns, differs from the set value at the immediately preceding time, the cooling air strength is changed. As a result, for example, when the skin color in the irradiation field changes to red during irradiation with light of blue or green wavelengths, the cooling air strength is changed to an appropriate value according to the change in skin color, thereby making it possible to reduce the risk of burns.

[0041] In this embodiment, when the opening 18 of the housing 5 is sealed by the upper surface of the skin 19 as described above, or when the distance between the opening and the upper surface of the skin is short, it is desirable to provide the camera inside the housing. By providing the camera inside the housing, it becomes possible to take pictures during light irradiation.

[0042] In this embodiment, the cooling unit 14 adjusts the cooling intensity by changing the intensity of the cooling air. The cooling air intensity adjustment unit 23 adjusts the cooling air intensity by controlling the rotation speed of the fan 15 according to a signal from the control unit 2. When the light passes through a Peltier element or a refrigerant, the light energy may be absorbed by them, and the output power of the light reaching the irradiation field may be reduced. By using the cooling air as the cooling unit 14, it becomes possible to irradiate the light to the irradiation field without losing the output power of the light. When the cooling air is used, the cooling intensity may be adjusted by controlling the intensity of the cooling air as well as adjusting the temperature of the cooling air. [Industrial Applicability]

[0043] The phototherapy device 1 of the present invention can be used as a medical device for low-output phototherapy for irritable bowel syndrome, and as a beauty device for hair removal treatment, etc. [Explanation of symbols]

[0044] 1 Phototherapy device 2. Control section 3. Probe 4 Cable 5. Cabinet 6 Light irradiation unit 12 Air Intake 13 Exhaust port 14 Cooling section 15 Fan 16 Duct 17, 17' Camera 18 Openings 19 Upper skin surface (irradiation area) 21 Light emission control section 22 Skin image acquisition section 23 Cooling air intensity adjustment section

Claims

1. A phototherapy device comprising a light irradiation unit that irradiates light rays onto the skin, which is the irradiation site, a cooling unit that cools the irradiation site, a skin information acquisition unit that acquires skin information of the irradiation site, and a cooling intensity adjustment unit that adjusts the cooling intensity of the cooling unit based on the acquired skin information.

2. The phototherapy device according to claim 1 , wherein the skin information acquisition unit is a skin color information acquisition unit that acquires color information of the skin of the irradiation site.

3. The phototherapy device according to claim 2 , wherein the skin color information acquisition unit is a skin image acquisition unit that acquires a skin image of the irradiation site acquired from a camera built into the phototherapy device or an external camera.

4. The phototherapy device according to claim 3, characterized in that the cooling unit is a cooling fan, and the cooling intensity adjustment unit is a means for adjusting the air volume of the cooling fan based on color information of the skin of the irradiated area acquired by the skin image acquisition unit.

5. The phototherapy device according to claim 4, characterized in that the skin color information is the pixel value of a grayscale image of the irradiated area, or the lightness L* and / or chromaticity a* of the L*a*b* color system of the color image, and the cooling intensity adjustment unit is a means for adjusting the air volume of the cooling fan based on the minimum pixel value in the grayscale image of the irradiated area, or the minimum L* value and / or the maximum a* value in the color image.

6. The phototherapy device according to claim 5, further comprising a light emission control unit that determines whether or not to emit light rays from the irradiation unit based on color information of the skin of the irradiated area acquired by the skin image acquisition unit, and that maintains a constant output power of the light rays when the light rays are emitted.

7. The phototherapy device according to claim 6, characterized in that when the skin color information exceeds a relational threshold between the skin color information and the cooling air volume for burn prevention risk reduction irradiation, emission of light rays from the irradiation unit is prohibited.

8. The phototherapy device according to claim 3, further comprising a memory means for storing image information of the skin at the irradiation site, and changing the airflow of the cooling fan when the detected skin image information differs from the immediately previous stored skin image information.

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