JP7618905B2 - Skin evaluation device, method, program, and system - Google Patents

Description

The present invention relates to a skin evaluation device, method, program, and system.

It has been known that the optical properties of an object (hereinafter referred to as optical properties) create textures such as gloss and transparency. It is also known that the optical properties of skin are involved in the textures such as "glossy skin," "matte skin," "transparency," and "dullness."

Textures such as "glossy skin," "matte skin," "transparency," and "dullness" are important factors that influence the perception of skin beauty. For this reason, skin is evaluated based on its optical properties (Patent Documents 1 to 5).

Patent No. 4133248 Patent No. 5340907 JP 2003-190120 A International Publication No. 2016/0158061 Patent No. 6029379

However, previous methods were unable to comprehensively evaluate all the light generated by the skin.

Therefore, the present invention aims to comprehensively evaluate the optical properties of skin.

One embodiment of the skin evaluation device includes an acquisition unit that acquires shape information and color information of skin irradiated with light, and a calculation unit that uses the shape information and color information to calculate the ratio of light specularly reflected from the surface of the skin due to the irradiation to the total light from the skin, the ratio of light diffusely reflected from the surface of the skin to the total light from the skin, and the ratio of light emitted to the outside of the skin after scattering inside the skin to the total light from the skin.

The present invention makes it possible to comprehensively evaluate the optical properties of skin.

1 is an overall configuration diagram according to an embodiment of the present invention; 1 is a functional block diagram of a skin evaluation device according to an embodiment of the present invention. 4 is a flowchart of a skin evaluation process according to an embodiment of the present invention. 11 is a flowchart of a light amount ratio calculation process according to an embodiment of the present invention. 1 is a diagram for explaining separation of surface reflection/subsurface scattering and separation of specular reflection/diffuse reflection according to an embodiment of the present invention. FIG. 1A to 1C are diagrams for explaining a method for separating surface reflection and subsurface scattering according to an embodiment of the present invention. 1 is a block diagram showing an example of a hardware configuration of a skin evaluation device according to an embodiment of the present invention.

The following describes an embodiment of the present invention based on the drawings.

<Terminology>
In this specification, "specular reflection" refers to the reflection of light that occurs on the surface of the skin, where the angle of incidence and the angle of reflection are equal.
In this specification, "diffuse reflection" refers to the reflection of light that occurs on the surface of the skin, excluding specular reflection.
As used herein, "subsurface scattering" refers to light passing through the surface of the skin, being scattered inside the skin, and then exiting the skin surface.

<Overall composition>
1 is a diagram showing the overall configuration of an embodiment of the present invention. The skin evaluation system 1 includes a skin evaluation device 10, an image capture device 20, and a light source 30. Each of these will be described below.

The skin evaluation device 10 is a computer for evaluating the optical characteristics of the skin. The skin evaluation device 10 uses the image captured by the imaging device 20 (specifically, using the skin shape information and skin color information) to calculate the amount of light specularly reflected on the surface of the skin by irradiation from the light source 30 (hereinafter also referred to as specular reflected light), the amount of light diffusely reflected on the surface of the skin by irradiation from the light source 30 (hereinafter also referred to as diffuse reflected light on the surface), and the amount of light emitted to the outside of the skin after scattering inside the skin by irradiation from the light source 30 (hereinafter also referred to as subsurface scattered light). In addition, the skin evaluation device 10 calculates the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of the amount of specular reflected light, the amount of diffuse reflected light on the surface, and the amount of subsurface scattered light). Furthermore, the skin evaluation device 10 can evaluate the skin based on at least one of the amount of light and the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of the amount of each amount of light). For example, the skin evaluation device 10 is a personal computer, a tablet terminal, a smartphone, etc.

In this way, the present invention evaluates the physical characteristics of the skin (skin shape) and the optical characteristics of the skin (all light generated by the skin) from images captured using a single imaging device 20 and a single light source 30.

The imaging device 20 is a device for photographing skin. Specifically, the imaging device 20 photographs the skin whose optical characteristics are to be evaluated.

The skin evaluation device 10 can obtain shape information and color information indicating the three-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate, and Z-coordinate values of each point, and the RGB values of each point) from the image captured by the imaging device 20, or shape information and color information indicating the two-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate values of each point, and the RGB values of each point).

Light source 30 is an artificial light source that emits its own light.

Note that in FIG. 1, the skin evaluation device 10, the imaging device 20, and the light source 30 are described as separate devices, but at least two of the skin evaluation device 10, the imaging device 20, and the light source 30 may be implemented in a single device.

<Function block>
Fig. 2 is a functional block diagram of the skin evaluation device 10 according to one embodiment of the present invention. As shown in Fig. 2, the skin evaluation device 10 can include an image acquisition unit 101, a calculation unit 102, and an evaluation unit 103. Moreover, the skin evaluation device 10 can function as the image acquisition unit 101, the calculation unit 102, and the evaluation unit 103 by executing a program.

The image acquisition unit 101 acquires an image of the skin illuminated with light from the light source 30 from the imaging device 20. From the image acquired from the imaging device 20, the image acquisition unit 101 acquires shape information and color information indicating the three-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate, and Z-coordinate values of each point, and the RGB values of each point), or shape information and color information indicating the two-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate values of each point, and the RGB values of each point).

The calculation unit 102 uses the skin shape information and skin color information to calculate the amount of light specularly reflected from the surface of the skin upon irradiation from the light source 30 (specular reflected light), the amount of light diffusely reflected from the surface of the skin upon irradiation from the light source 30 (diffuse reflected light at the surface), and the amount of light emitted to the outside of the skin after scattering inside the skin upon irradiation from the light source 30 (subsurface scattered light). The calculation unit 102 also calculates the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light). Below, the explanation is divided into <<Separation of surface reflection and subsurface scattering>> and <<Separation of specular reflection and diffuse reflection>>.

<<Separation of surface reflection and subsurface scattering>>
The calculation unit 102 calculates the amount of light reflected by the surface of the skin (hereinafter also referred to as surface reflected light) and the amount of light (subsurface scattered light) emitted to the outside of the skin after scattering inside the skin. In addition, the calculation unit 102 calculates the ratio of the amount of surface reflected light to the sum of the amount of surface reflected light and the amount of subsurface scattered light, and the ratio of the amount of subsurface scattered light to the sum of the amount of surface reflected light and the amount of subsurface scattered light.

For example, the calculation unit 102 calculates the difference between the amount of light in the illuminated area and the amount of light in the non-illuminated area in an image of skin onto which illuminated and non-illuminated pattern light is projected by a projector, and separates the light into a component of light reflected on the surface of the skin (surface reflected light) and a component of light emitted to the outside of the skin after scattering inside the skin (subsurface scattered light). Based on the separation, the calculation unit 102 calculates the amount of light (i.e., the amount of surface reflected light and the amount of subsurface scattered light) and the ratio of each amount of light to the total amount of light from the skin (i.e., the ratio of the amount of surface reflected light to the sum of the amount of surface reflected light and the amount of subsurface scattered light, and the ratio of the amount of subsurface scattered light to the sum of the amount of surface reflected light and the amount of subsurface scattered light).

<<Separation of specular reflection and diffuse reflection>>
The calculation unit 102 calculates the amount of light specularly reflected from the skin surface (specular reflected light) and the amount of light diffusely reflected from the skin surface (diffuse reflected light from the surface). The calculation unit 102 also calculates the ratio of the amount of specular reflected light to the sum of the amount of specular reflected light and the amount of diffuse reflected light from the surface, and the ratio of the amount of diffuse reflected light from the surface to the sum of the amount of specular reflected light and the amount of diffuse reflected light from the surface.

For example, the calculation unit 102 calculates the difference between an unpolarized image captured using a polarizing filter and a polarized image captured without using a polarizing filter, and separates the component of light specularly reflected from the skin surface (specular reflected light) from the total amount of light from the skin (note that since the total amount of light from the skin = specular reflected light + other light (diffuse reflected light from the surface + subsurface scattered light), the light remaining after separation includes diffuse reflected light from the surface and subsurface scattered light). The calculation unit 102 can calculate the amount of diffuse reflected light from the surface by subtracting the subsurface scattered light from the remaining light after separation.

Based on the separation, the calculation unit 102 calculates the amount of each light (i.e., the amount of specular reflected light and the amount of diffuse reflected light at the surface) and the ratio of each amount of light to the total amount of light from the skin (i.e., the ratio of the amount of specular reflected light to the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light, and the ratio of the amount of diffuse reflected light at the surface to the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light). Note that although the present specification describes a method using a polarizing filter, the present invention can also apply a separation method using a dichroic reflection model and a method of separating specular reflection using shape information.

Note that the light reflected from the skin surface in <<Separation of surface reflection and subsurface scattering>> consists of light specularly reflected from the skin surface and light diffusely reflected from the skin surface in <<Separation of specular reflection and diffuse reflection>>.

The evaluation unit 103 evaluates the skin based on at least one of the amounts of light calculated by the calculation unit 102 (i.e., the amount of specularly reflected light, the amount of diffusely reflected light on the surface, and the amount of subsurface scattered light) and the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of each amount of light). For example, the evaluation unit 103 can evaluate the skin based on the difference between the ratio calculated by the calculation unit 102 and a predetermined ratio (e.g., the ratio at which the skin looks most beautiful). For example, the evaluation unit 103 can evaluate the skin based on the correspondence between the ratio (the ratio of the amount of light specularly reflected on the surface of the skin due to irradiation, the light diffusely reflected on the surface of the skin, and the light emitted to the outside of the skin after scattering inside the skin) and the skin condition.

For example, the evaluation unit 103 can evaluate the skin as having a glossy appearance when the amount of light specularly reflected from the skin surface is large. Also, for example, the evaluation unit 103 can evaluate the skin as having a matte appearance when the amount of light diffusely reflected from the skin surface is large. Also, for example, the evaluation unit 103 can evaluate the skin as having a translucent appearance when the amount of light emitted to the outside of the skin after being scattered inside the skin is large.

<<Light intensity correction based on 3D skin shape>>
In one embodiment of the present invention, the skin evaluation device 10 can correct (i.e., increase or decrease) at least one of the amount of specular reflected light, the amount of diffusely reflected light on the surface, and the amount of subsurface scattered light based on shape information indicating the three-dimensional shape of the skin. The specular reflection of the skin is affected by the shape of the skin, such as the unevenness of the surface. In other words, differences in shape, such as whether the cheeks are plump or not, affect the evaluation of the specular reflection (i.e., skin luster). Not only specular reflection, but also the way light hits the skin varies depending on the shape of the skin. Therefore, in one embodiment of the present invention, the three-dimensional shape of the skin is utilized to correct the amount of light hitting each part (for example, each part of the face, such as the cheeks) to improve the accuracy of the evaluation of the optical properties of the skin.

Methods
Hereinafter, the skin evaluation process will be described with reference to FIG. 3, and the light amount ratio calculation process will be described with reference to FIG.

Figure 3 is a flowchart of a skin evaluation process according to one embodiment of the present invention.

In step 1 (S1), the image acquisition unit 101 acquires an image of skin illuminated with light from the light source 30 from the imaging device 20. Next, the image acquisition unit 101 acquires shape information and color information indicating the three-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate, and Z-coordinate values of each point, and the RGB values of each point) or shape information and color information indicating the two-dimensional shape of the skin (specifically, the X-coordinate, Y-coordinate values of each point, and the RGB values of each point) from the image acquired from the imaging device 20.

In step 2 (S2), the calculation unit 102 uses the skin shape information and skin color information acquired in S1 to calculate the amount of light specularly reflected from the surface of the skin upon irradiation from the light source 30 (specular reflected light), the amount of light diffusely reflected from the surface of the skin upon irradiation from the light source 30 (diffuse reflected light at the surface), and the amount of light emitted to the outside of the skin after scattering inside the skin upon irradiation from the light source 30 (subsurface scattered light). Next, the calculation unit 102 calculates the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light).

In step 3 (S3), the evaluation unit 103 evaluates the skin based on at least one of the amounts of light calculated in S2 (i.e., the amount of specularly reflected light, the amount of diffusely reflected light on the surface, and the amount of subsurface scattered light) and the ratio of each amount of light to the total amount of light from the skin (i.e., the sum of each amount of light). For example, the evaluation unit 103 can evaluate the skin based on the difference between the ratio calculated in S2 and a predetermined ratio. For example, the evaluation unit 103 can evaluate the skin based on the correspondence between the ratio (the ratio of the amount of light specularly reflected on the surface of the skin due to irradiation, the light diffusely reflected on the surface of the skin, and the light emitted to the outside of the skin after scattering inside the skin) and the skin condition.

Figure 4 is a flowchart of the light intensity ratio calculation process (S2 in Figure 3) according to one embodiment of the present invention.

In step 11 (S11), the calculation unit 102 separates surface reflection and subsurface scattering. Specifically, the calculation unit 102 calculates the amount of light reflected on the surface of the skin (surface reflected light) and the amount of light emitted to the outside of the skin after scattering inside the skin (subsurface scattered light). Next, the calculation unit 102 calculates the ratio of the amount of surface reflected light to the sum of the amount of surface reflected light and the amount of subsurface scattered light, and the ratio of the amount of subsurface scattered light to the sum of the amount of surface reflected light and the amount of subsurface scattered light.

For example, the calculation unit 102 calculates the difference between the amount of light in the illuminated area and the amount of light in the non-illuminated area in an image of skin onto which illuminated and non-illuminated pattern light is projected by a projector. Next, based on the difference, the calculation unit 102 separates the light into a component of light reflected on the surface of the skin (surface reflected light) and a component of light emitted to the outside of the skin after scattering inside the skin (subsurface scattered light). Next, based on the separation, the calculation unit 102 calculates the amount of light (i.e., the amount of surface reflected light and the amount of subsurface scattered light) and the ratio of each amount of light to the total amount of light from the skin (i.e., the ratio of the amount of surface reflected light to the sum of the amount of surface reflected light and the amount of subsurface scattered light, and the ratio of the amount of subsurface scattered light to the sum of the amount of surface reflected light and the amount of subsurface scattered light).

In step 12 (S12), the calculation unit 102 separates specular reflection from diffuse reflection. Specifically, the calculation unit 102 calculates the amount of light specularly reflected from the skin surface (specular reflected light) and the amount of light diffusely reflected from the skin surface (diffuse reflected light at the surface). Next, the calculation unit 102 calculates the ratio of the amount of specular reflected light to the sum of the amount of specular reflected light and the amount of diffuse reflected light at the surface, and the ratio of the amount of diffuse reflected light at the surface to the sum of the amount of specular reflected light and the amount of diffuse reflected light at the surface.

For example, the calculation unit 102 calculates the difference between a non-polarized image captured using a polarizing filter and a polarized image captured without using a polarizing filter. Next, based on the difference, the calculation unit 102 separates the light into a component of light specularly reflected (specular reflected light) from a component of light diffusely reflected (diffuse reflected light at the surface) from the skin surface. Next, based on the separation, the calculation unit 102 calculates the amount of light of each component (i.e., the amount of specular reflected light and the amount of diffuse reflected light at the surface) and the ratio of each amount of light to the total amount of light from the skin (i.e., the ratio of the amount of specular reflected light to the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light, and the ratio of the amount of diffuse reflected light at the surface to the sum of the amount of specular reflected light, the amount of diffuse reflected light at the surface, and the amount of subsurface scattered light).

The light reflected by the skin surface of S11 consists of light specularly reflected by the skin surface of S12 and light diffusely reflected by the skin surface of S12.

Figure 5 is a diagram explaining the separation of surface reflection/subsurface scattering and the separation of specular reflection/diffuse reflection according to one embodiment of the present invention.

The imaging device 20 captures the skin of the user's face illuminated with light from the light source 30. Specifically, the imaging device 20 captures an image for separating surface reflection and subsurface scattering, and an image for separating specular reflection and diffuse reflection. Thus, in the present invention, the image for separating surface reflection and subsurface scattering, and the image for separating specular reflection and diffuse reflection are captured using a single imaging device 20 and a single light source 30. The skin evaluation device 10 acquires information indicating the shape (three-dimensional shape or two-dimensional shape) and color of the skin from the image, and calculates the amount of light (specular reflected light) specularly reflected on the surface of the skin by irradiation from the light source 30, the amount of light (diffuse reflected light on the surface) diffusely reflected on the surface of the skin by irradiation from the light source 30, and the amount of light (subsurface scattered light) emitted to the outside of the skin after scattering inside the skin by irradiation from the light source 30. The skin evaluation device 10 then calculates the ratio of each light amount to the total amount of light from the skin (i.e., the sum of the amount of specularly reflected light, the amount of diffusely reflected light from the surface, and the amount of subsurface scattered light).

Figure 6 is a diagram explaining a method for separating surface reflection and subsurface scattering according to one embodiment of the present invention.

In step 101 (S101), the projector (light source 30) projects illuminated and non-illuminated pattern light onto the user's face. The imaging device 20 also captures the user's face onto which the illuminated and non-illuminated pattern light is projected. In FIG. 6, the black parts (i.e., the parts not projected) are the non-illuminated areas, and the other parts (i.e., the parts projected) are the illuminated areas.

In step 102 (S102), light from the projector (light source 30) is reflected on the surface of the skin, or passes through the surface of the skin and is scattered inside the skin before exiting the surface of the skin. Arrow 1 in FIG. 6 indicates light emitted by the projector (light source 30). Arrow 2 in FIG. 6 indicates light that is specularly reflected in the illuminated area. Arrow 3 in FIG. 6 indicates light that is diffusely reflected in the illuminated area. Arrow 4 in FIG. 6 indicates light that is emitted to the outside of the skin after scattering inside the skin in the illuminated and non-illuminated areas. Arrow 5 in FIG. 6 indicates light that is scattered inside the skin.

In step 103 (S103), the projector (light source 30) moves the irradiated and non-irradiated pattern light projected onto the user's face, and changes the area that was an irradiated area in S101 to a non-irradiated area (i.e., the area that was a non-irradiated area becomes an irradiated area). In addition, the imaging device 20 captures an image of the user's face onto which the moved irradiated and non-irradiated pattern light is projected.

By S101 and S103, the light components in the illuminated areas and the light components in the non-illuminated areas of the entire face are obtained. The calculation unit 102 of the skin evaluation device 10 can obtain the light components reflected on the skin surface by subtracting the light components in the non-illuminated areas of S101 and S103 (i.e., areas where only light that is scattered inside the skin and then emitted to the outside of the skin exists) from the light components in the illuminated areas of S101 and S103 (i.e., areas where both light reflected on the skin surface and light that is scattered inside the skin and then emitted to the outside of the skin exist).

＜Effects＞
In this way, the present invention can comprehensively evaluate the optical characteristics of skin. Specifically, the present invention evaluates the physical characteristics of skin (skin shape) and the optical characteristics of skin (all light generated by skin) from an image captured using a single imaging device 20 and a single light source 30. Therefore, the ratio of the amount of light of each type of light (i.e., specular reflection, diffuse reflection, subsurface scattering) can be calculated, and the texture of skin can be comprehensively and quantitatively evaluated based on the balance of light.

<Hardware Configuration>
FIG. 7 is a block diagram showing an example of the hardware configuration of the skin evaluation device 10 according to one embodiment of the present invention.

The skin evaluation device 10 has a CPU (Central Processing Unit) 1001, a ROM (Read Only Memory) 1002, and a RAM (Random Access Memory) 1003. The CPU 1001, the ROM 1002, and the RAM 1003 form a so-called computer.

The skin evaluation device 10 may also have an auxiliary storage device 1004, a display device 1005, an operation device 1006, an I/F (Interface) device 1007, and a drive device 1008. Each piece of hardware in the skin evaluation device 10 is connected to each other via a bus B.

The CPU 1001 is a computing device that executes various programs installed in the auxiliary storage device 1004.

The ROM 1002 is a non-volatile memory. The ROM 1002 functions as a primary storage device that stores various programs, data, etc. required for the CPU 1001 to execute various programs installed in the auxiliary storage device 1004. Specifically, the ROM 1002 functions as a primary storage device that stores boot programs such as the Basic Input/Output System (BIOS) and the Extensible Firmware Interface (EFI).

RAM 1003 is a volatile memory such as a dynamic random access memory (DRAM) or a static random access memory (SRAM). RAM 1003 functions as a primary storage device that provides a working area in which various programs installed in the auxiliary storage device 1004 are expanded when they are executed by the CPU 1001.

The auxiliary storage device 1004 is an auxiliary storage device that stores various programs and information used when the various programs are executed.

The display device 1005 is a display device that displays the internal state of the skin evaluation device 10, etc.

The operation device 1006 is an input device through which the administrator of the skin evaluation device 10 inputs various instructions to the skin evaluation device 10.

The I/F device 1007 is a communication device that connects to a network and communicates with the skin evaluation device 10.

The drive unit 1008 is a device for setting the storage medium 1009. The storage medium 1009 here includes media that record information optically, electrically, or magnetically, such as CD-ROMs, flexible disks, and magneto-optical disks. The storage medium 1009 may also include semiconductor memory that records information electrically, such as EPROM (Erasable Programmable Read Only Memory) and flash memory.

The various programs to be installed in the auxiliary storage device 1004 are installed, for example, by setting the distributed storage medium 1009 in the drive device 1008 and reading the various programs recorded on the storage medium 1009 by the drive device 1008. Alternatively, the various programs to be installed in the auxiliary storage device 1004 may be installed by downloading them from a network via the I/F device 1007.

Although the examples of the present invention have been described in detail above, the present invention is not limited to the specific embodiments described above, and various modifications and variations are possible within the scope of the gist of the present invention as described in the claims.

REFERENCE SIGNS LIST 1 Skin evaluation system 10 Skin evaluation device 20 Imaging device 30 Light source 101 Image acquisition unit 102 Calculation unit 103 Evaluation unit 1001 CPU
1002 ROM
1003 RAM
1004 Auxiliary storage device 1005 Display device 1006 Operation device 1007 I/F device 1008 Drive device 1009 Storage medium

Claims (10)

an acquisition unit that acquires shape information and color information of skin irradiated with light;
a calculation unit that uses the shape information and color information to calculate a ratio of an amount of light specularly reflected on the surface of the skin by the irradiation to the total amount of light from the skin, a ratio of an amount of light diffusely reflected on the surface of the skin to the total amount of light from the skin, and a ratio of an amount of light emitted to the outside of the skin after scattering inside the skin to the total amount of light from the skin ,
A skin evaluation device, wherein the total light from the skin is the sum of the amount of light specularly reflected from the surface of the skin due to the irradiation, the amount of light diffusely reflected from the surface of the skin, and the amount of light emitted to the outside of the skin after scattering inside the skin . The skin evaluation device according to claim 1, wherein the calculation unit calculates the amount of light specularly reflected by the surface of the skin due to the irradiation, the amount of light diffusely reflected by the surface of the skin, and the amount of light emitted to the outside of the skin after scattering inside the skin. The skin evaluation device according to claim 1 or 2, wherein the shape information indicates a three-dimensional shape of the skin. The calculation unit is
The light is separated into light reflected on the surface of the skin and light emitted to the outside of the skin after scattering inside the skin;
Separating light into specularly reflected light from the surface of the skin and light diffusely reflected from the surface of the skin;
The skin evaluation device according to claim 1 , wherein the light reflected from the skin surface comprises light specularly reflected from the skin surface and light diffusely reflected from the skin surface. The skin evaluation device according to any one of claims 1 to 4, further comprising an evaluation unit that evaluates the skin based on the calculated ratio. The skin evaluation device according to claim 5, wherein the evaluation unit evaluates the skin based on the difference between the calculated ratio and a predetermined ratio. The skin evaluation device according to claim 5, wherein the evaluation unit evaluates the skin based on the correspondence between the ratio and the skin condition. acquiring shape information and color information of the skin irradiated with light;
and using the shape information and color information, calculating a ratio of an amount of light specularly reflected on the surface of the skin by the irradiation to the total amount of light from the skin, a ratio of an amount of light diffusely reflected on the surface of the skin to the total amount of light from the skin, and a ratio of an amount of light emitted to the outside of the skin after scattering inside the skin to the total amount of light from the skin ,
A method in which the total light from the skin is the sum of the amount of light specularly reflected from the surface of the skin due to the irradiation, the amount of light diffusely reflected from the surface of the skin, and the amount of light emitted to the outside of the skin after scattering inside the skin . An acquisition unit that acquires shape information and color information of the skin irradiated with light;
a calculation unit that calculates, using the shape information and color information, a ratio of the amount of light specularly reflected on the surface of the skin by the irradiation to the total amount of light from the skin, a ratio of the amount of light diffusely reflected on the surface of the skin to the total amount of light from the skin, and a ratio of the amount of light emitted to the outside of the skin after scattering inside the skin to the total amount of light from the skin ,
The total light from the skin is the sum of the amount of light specularly reflected from the surface of the skin due to the irradiation, the amount of light diffusely reflected from the surface of the skin, and the amount of light emitted to the outside of the skin after scattering inside the skin . A skin evaluation system including a skin evaluation device, an imaging device, and a light source,
The skin evaluation device includes:
an acquisition unit that acquires shape information and color information of skin irradiated with light from the light source from the image captured by the imaging device;
a calculation unit that calculates, using the shape information and color information, a ratio of an amount of light specularly reflected on the surface of the skin by irradiation from the light source to the total amount of light from the skin, a ratio of an amount of light diffusely reflected on the surface of the skin by irradiation from the light source to the total amount of light from the skin, and a ratio of an amount of light emitted to the outside of the skin after scattering inside the skin by irradiation from the light source to the total amount of light from the skin ,
A skin evaluation system in which the total light from the skin is the sum of the amount of light specularly reflected from the surface of the skin due to the irradiation, the amount of light diffusely reflected from the surface of the skin, and the amount of light emitted to the outside of the skin after scattering inside the skin .

Images