JP2011110354A - Method for distinguishing skin characteristics by using high-speed camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technique for distinguishing skin characteristics such as "softness", "resilience", or "smoothness", which is realized and easily recognized by a person. <P>SOLUTION: The technique is the one for distinguishing the skin characteristics such as "softness", "resilience", or "smoothness" by photographing the change (displacement) of a spherical body on a skin surface by using a high-speed camera and performing image processing analysis concerning the photographed change of the spherical body. A skin characteristics distinguishing system includes: the spherical body to be dropped onto the skin surface; a fixing means for holding the spherical body; the high-speed camera for photographing the change of the spherical body after the spherical body is dropped; and an analyzing and displaying means for processing, analyzing and displaying an image. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a skin property discrimination method, and more specifically to a skin property discrimination method and a discrimination system using a high-speed camera.

  Skin conditions vary depending on skin properties, skin quality, age, environment, and care methods, so it is extremely important for both men and women to choose skin care and cosmetics suitable for each person. It is a serious concern. Various methods for accurately and simply measuring and evaluating the skin condition for this purpose have been studied. Important items of such a skin condition include items such as skin softness, elasticity and smoothness that are highly related to the aging phenomenon. As a method for measuring these items, for example, a cutometer MPA580 (registered trademark) manufactured by C + K, a skin condition measuring device (see Patent Document 1), a regiometer (see Patent Document 2), etc. are disclosed, and the viscoelasticity of the skin is disclosed. The properties of dermal collagen fiber bundles have been evaluated.

  On the other hand, in recent years, a high-speed camera (or high-speed camera) capable of taking a photograph at a high speed, for example, several hundred frames / second or more has been developed, and a material impact test apparatus (see Patent Document 3) using the high-speed camera has been developed. A living body observation apparatus (see Patent Document 4) is disclosed. Furthermore, a method for evaluating skin properties such as skin elasticity and tension using this high-speed camera is disclosed (Patent Document 5). Such technology has revealed that, for example, the feeling of tightness of the skin property and the numerical value of the area by image processing, etc. are related. However, the person had no real feeling and was not able to be recognized and convinced. This is because a high-speed camera is simply used as a measuring instrument, and the measured index is merely an area value of the deformed skin.

  Under such circumstances, the present inventors have conducted intensive research and search for an evaluation method that makes the skin characteristics such as softness, elasticity, and smoothness more visually, more realistic and easy to recognize. Here, the present inventors have found that in the information processing science and cognitive psychology of the brain, there is a visual superiority in spatial perception, and there is a visual / tactile interaction and a mutual complementing effect. In other words, humans obtain 90% of external information from the sight, and, for example, sensory terms such as softness, elasticity, elasticity, etc. are common terms for sight and touch. And there is an important relationship of mutual complementarity. That is, if skin characteristics are evaluated using such a phenomenon, it can be considered to be a method for evaluating skin characteristics that is easy to feel and recognize, supported by both visual and tactile sensations. More specifically, since a sphere that falls or rolls on the skin takes a behavior controlled by the skin characteristics, there is a correlation between the sensory evaluation value of the skin characteristics and the characteristic values of the spheres on the skin surface. The skin characteristics such as tactile softness, elasticity and smoothness are determined by the change of the sphere on the skin surface determined by the index, and the skin characteristics such as visual softness, elasticity and smoothness are determined. A characteristic is that a person feels and is easy to recognize. In this way, using the change of the sphere on the skin surface as an index makes it possible to realize skin characteristics such as visual softness, elasticity, and smoothness, and to realize a discrimination method that feels and is easy to recognize. It was not done.

Japanese Patent Laid-Open No. 11-137525 Table 01/052724 JP 2006-047277 A JP 2009-229745 A JP 2006-346020 A

  It is an object of the present invention to provide a technique for distinguishing skin characteristics such as “softness”, “elasticity”, and “smoothness” that can be realized and recognized by humans.

In view of such a situation, the present inventors have sought for a technique for distinguishing skin characteristics such as “softness”, “elasticity”, and “smoothness”, which humans feel and recognize easily. As a result, the change (displacement) of the sphere on the skin surface is photographed with a high-speed camera, and the photographed sphere is image-processed and analyzed. The inventors have found that it is possible to provide a technique for distinguishing skin characteristics such as “elasticity” or “smoothness” and have completed the invention. That is, this invention relates to the technique shown below.

(1) A method for distinguishing skin characteristics, wherein a change (displacement) of a sphere on the skin surface is photographed by a high-speed camera, and the photographed sphere is subjected to image processing analysis.
(2) The skin characteristic discrimination method according to (1), wherein the skin characteristic is determined by a correlation between a sensory evaluation value of a skin surface state and a characteristic value of a sphere on the skin surface. .
(3) The method for distinguishing skin characteristics according to (1) or (2), wherein the skin characteristics are selected from “softness” or “elasticity”.
(4) The skin characteristic discrimination method according to (1) or (2), wherein the skin characteristic is “smoothness”.
(5) A sphere to be dropped on the skin surface, a fixing means for holding the sphere, a high-speed camera for photographing a sphere change after the sphere is dropped, and an analysis for processing, analyzing, and displaying an image photographed by the high-speed camera -A system for distinguishing skin characteristics comprising display means.

  ADVANTAGE OF THE INVENTION According to this invention, the discrimination technique of skin characteristics, such as "softness", "elasticity", or "smoothness" which a person can feel and recognize easily, can be provided.

(1) Method for distinguishing skin characteristics of the present invention The present invention captures a change (displacement) of a sphere on the skin surface with a high-speed camera (or a high-speed camera), and performs image processing analysis on the change of the captured sphere In this technique, the skin characteristics are differentiated using the index obtained by the image processing analysis (see FIG. 1). Further details are described below.

  The sphere on the skin shows a change in whether the sphere falls on the subject's skin and then rebounds or rebounds, but such a change (displacement) is influenced and governed by the skin surface condition. That is, as will be apparent from examples described later, for example, if the skin characteristic is “soft”, the sphere that has fallen as the skin is softer sinks into the skin, and the amount of displacement of the sphere that sinks into the skin from the skin surface The “indentation amount” defined as is large (see FIG. 2). A sphere that has fallen into the skin bounces back in the opposite direction after being sunk into the skin, but the greater the `` elasticity '' of the skin characteristics, the greater the amount of sag and the maximum amount of displacement that bounces off the skin surface. The “bounce amount” is large. FIG. 3 shows the relationship between the amount of displacement of the sphere due to the fall of the sphere and its time.

  On the other hand, when the sphere rolls on the skin, the greater the “smoothness” of the skin characteristics, the lower the rolling resistance of the sphere and the faster the rolling speed. Thus, each sensory evaluation value of the skin surface state and the characteristic value of the sphere on the skin surface have a significant and good correlation. Therefore, by utilizing this visual tactile correlation, the characteristic value of the visual sphere is the sensory evaluation value of the tactile skin characteristic, and the skin is easy to feel and recognize, supported by both visual and tactile sensations. It can be a method for evaluating characteristics.

  In the evaluation of “softness” and “elasticity”, the target site must have a flatness with a sufficient area compared to the projected area of the sphere, and bones etc. must exist within 2 to 3 mm from the skin surface in the internal direction. For example, cheeks, chests, upper arms, forearms, legs, etc. can be preferably exemplified. In addition, in the evaluation of “smoothness”, flatness should be provided within the range in which the rolling evaluation is performed (for example, width 1 cm, length 1 to 5 cm). For example, chest, upper arm, forearm, leg, etc. Can be preferably exemplified.

  Since the change of the sphere on the skin is a very high-speed change, it cannot be said that it has been sufficiently recognized by visual recognition. Therefore, it is preferable from the viewpoint of cognitive characteristics that such a change is photographed by a high-speed camera and subjected to image processing analysis or the like to obtain a sphere characteristic value corresponding to visual recognition. For example, if the skin characteristic is “elasticity”, the tactile skin elasticity is generally determined by the speed of return of the surface of the skin when the skin is pressed with 40 to 60 g with the middle finger or the like. The visual characteristic value may be set so that the sphere drops on the skin and jumps up. That is, the relationship between the two is very easy to realize and recognize by the visual-tactile interaction. In the case of “softness”, it is generally the softness when the skin is touched with 40 to 60 g with the middle finger or the like. On the other hand, in the case of “smoothness”, it is 5 on the skin with the middle finger or the like. Since it is a slip resistance feeling when it is slid at 10 g, it can be considered exactly the same as the above-mentioned “elasticity”. This is also clear from the fact that each sensory evaluation value of tactile softness, elasticity or smoothness and the characteristic value of the visual sphere show a significant and high correlation in the examples described later.

  The sensory evaluation profile used for the evaluation method of the tactile softness, elasticity, or smoothness may be prepared by organizing and scaling by a commonly used statistical analysis method. However, since these terms are already common as sensory evaluation terms, it is sufficient to clarify the point of focus and the method, and the evaluation scale should be 3 to 9, preferably 5 or 7, odd. Also, the evaluation axis is preferably centered at 0 (neither), with ± 2 or ± 3 on the left and right, and the opposite adjectives representing the degree corresponding to the evaluation item are used. The numerical value ± 2 or ± 3 of the evaluation axis may be converted into 1 to 5 or 1 to 7 for processing. In addition, when using this sensory evaluation profile, it is preferable to prepare a skin substitute reference material that is a reference value for each evaluation item using silicon, urethane, or the like. For a plurality of subjects in their skin conditions in their 20s and 60s, the sensory evaluation profile reference may be matched between the evaluators.

(2) Skin Characteristics Identification System of the Present Invention FIG. 1 shows a schematic configuration diagram of a skin characteristics identification system. This skin characteristic identification system includes a sphere 1 to be dropped, a fixing means 2 for holding the sphere 1, a high-speed camera 3 for photographing changes in the sphere 1, and a high-speed camera. The high-speed camera 3 and the analysis / display unit 4 are connected to each other. The high-speed camera 3 is connected to the analysis / display unit 4.

  The sphere 1 shows a change (or displacement) in which the sphere 1 is fixed in the air or on the skin by the fixing means 2 and then bounces after falling on the skin or rolls along the inclination of the skin. Photographed using the camera 3.

  Between the changing characteristics of a sphere falling on the subject's skin, bouncing back or rolling down the skin, and the sensory characteristics of softness, elasticity, or smoothness that humans can feel and recognize It is essential that there be a good correlation. In addition, the size, material, and weight of the sphere 1 are limited by the relationship between the skin area and the shape of the skin, which are the measurement target parts of the subject and the subject. For example, as the material of the sphere, metals or resins are preferable, specifically, stainless steel, carbon steel, aluminum, bronze, steel, titanium, and alloys thereof, or polypropylene, nylon, polyacetal, fluororesin, Preferred examples include polyether ketone, urethane, silicon and the like. Similarly, the size is preferably 1 to 10 mm in diameter and the weight is preferably 0.01 to 4.0 g.

  The fixing means 2 may have a function of temporarily fixing the sphere 1 in the air or on the skin, and then bouncing down after being dropped on the skin, or rolling along the inclination of the skin. A type, a clamp type or a gate type can be preferably exemplified. Here, the position at which the sphere is dropped when evaluating “softness” and “elasticity”, that is, the height H in FIG. 1 is subject to restrictions on the safety of the subject, the size and weight of the sphere, 10-40 cm can be illustrated. On the other hand, when evaluating the “smoothness”, it is preferable that the sphere is rolled on the skin (height H = 0 cm) from the viewpoint of good reproducibility, and when rolling on the skin, It is preferable in terms of reproducibility that the size and weight of the sphere is smaller and lighter than when it is dropped on the skin.

  What is necessary is just to use what is already marketed for the high speed camera 3, for example, the motion analysis microscope VW-6000 of Keyence, the high speed camera Phantom (registered trademark) of Novic, and the high speed of Nack Image Technology. The camera system MEMRECAM series can be exemplified.

  The analysis / display unit 4 processes, analyzes, and displays an image taken by the high-speed camera from the high-speed camera. Most of the above-mentioned commercially available high-speed cameras are measurement systems that are attached to or integrated with a personal computer equipped with motion analysis or image analysis software. By using this system, standard analysis results and image information can be acquired. can do. In addition, if the analysis results obtained are further used for multivariate analysis such as correlation analysis, regression analysis, discriminant analysis, principal component analysis, image analysis, etc., the present invention is realized and recognized by humans. It is possible to provide information for easily distinguishing skin characteristics such as “softness”, “elasticity”, and “smoothness”.

  Hereinafter, the present invention will be described in more detail with reference to examples, but it is needless to say that the present invention is not limited to these examples.

<Distinction of skin characteristics "soft">
The relationship between the softness of the skin evaluation and the skin characteristics of the present invention was examined by the following methods and conditions, and the results and changes in the sphere were presented to the subject to confirm the validity and actual feeling. That is, after 30 minutes of face washing, a sphere is dropped on the subject's cheek, and image processing analysis is performed on the captured high-speed camera data to calculate the amount of softness “sinking amount”. The relationship with the sensory evaluation value was analyzed. As shown in Table 1, the results of the sensory evaluation value of softness and the amount of penetration were in good agreement, and each subject was fully convinced of the results. From this, it can be seen that the discrimination method of the present invention has the effect of distinguishing the skin characteristics that the subject strongly feels and recognizes by the visual recognition that the sphere sinks into the skin and the tactile recognition that is sensory evaluation.

<Measurement method and conditions>
-Evaluation target: cheeks of three female subjects (A, B, C) (1.5 cm above the intersection of the corner of the eye and the nose)
・ Skin characterization system: Fig. 1 (H = 25cm), sphere: stainless steel ball (SUJ-2, φ7.14)
・ High-speed camera: Motion analysis microscope VW-6000 manufactured by Keyence Corporation
・ Skin evaluation: Smooth evaluation based on sensory evaluation profile by three professional evaluators (5: soft to 3: normal to 1: hard)

In Example 1, the number of female subjects was increased (N = 15), and the same analysis and rank correlation analysis / regression analysis were performed. The results are shown in FIG. 4 and the following. From this, it can be seen that the relationship between the two is significant and highly correlated, and that the discrimination method of the present invention has a skin characteristic discrimination effect that makes the subject feel and recognize it strongly. In addition, it is possible to estimate the softness of sensory evaluation that is easier to recognize by using the obtained regression equation, and to use skin counseling etc. together with visual information of sphere changes by high speed camera You can also.
"Softness" = 1.03 * "Indentation amount" -2.22 (r = 0.718, P <0.01)

<Difference between skin properties of "elasticity">
The skin evaluation in Examples 1 and 2 was changed from softness to elasticity, and after calculating the “bounce amount” which is the amount of elastic displacement, the same evaluation as described above was performed. The results are shown in FIG. From this, it can be seen that the same thing as the skin property “softness” also exists in the skin property “elasticity”, and that the discrimination method of the present invention has a discrimination effect of the skin property that is strongly felt and recognized by the subject.
・ Skin evaluation: Three-stage evaluation based on sensory evaluation profile by three professional evaluators (3: Elasticity-2: Normal-1: No elasticity)
“Resistance” = 0.30 * “Rebound” +0.44 (r = 0.687, P <0.01)

<Differential identification of skin characteristics>
The skin evaluation of Example 1 was changed from softness to smoothness, and after calculating the rolling speed from the time required for the sphere, which is a smooth displacement amount, to move a distance of 20 mm on the skin, the skin characteristics of the present invention “ We examined the relationship with "smoothness" and presented the results and changes in the sphere to the subjects to confirm their validity and real feeling. As shown in Table 2, the results of the smoothness-ranking speed were in good agreement, and each subject was fully convinced of the results. From this, it can be seen that the skin characteristic “smoothness” of the present invention also has an effect of distinguishing the skin characteristic that is strongly felt and recognized by the subject.

<Measurement method and conditions>
・ Evaluation target: Upper arm bare skin of 3 female subjects (S, B, C) (30 minutes after washing)
・ Skin characterization system: Fig. 1 (H = 0cm), sphere: stainless steel ball (SUJ-2, φ2.38)
-Skin evaluation: ranking of 3 subjects' skin smoothness by 3 expert evaluators

<Test example: Identification of “smoothness” of skin by cream application>
In Example 4, after increasing the number of female subjects (N = 10), washing the inner left forearm 30 minutes, and then applying a certain amount of two types of creams A or B having different smoothness feelings to the skin described below Similarly, a rolling test was performed to calculate the rolling speed. Moreover, all subjects evaluated the smoothness when creams A and B were separately applied. Considering the order effect, half the cream application order was reversed. FIG. 6 is a graph of the average value of 10 rolling speeds of a sphere when creams A and B are applied. 90% of the subjects evaluated that the cream A was applied more easily. Cream A, which has a smoother skin evaluation than the above, has a significantly higher rolling speed (t-test when there is a correspondence, P <0.0001), and the discrimination method of the present invention is the smoothness of the skin by applying the cream. It can be seen that it can also be used for effect discrimination.

<Preparation method of creams A and B>
Creams A and B were produced according to the method shown below. That is, each of the components of (a) and (b) is heated to 80 ° C. to dissolve and homogenize the components, and then (ii) is gradually added and emulsified while stirring with a homomixer. This was stirred and cooled to obtain creams A and B.

<Cream A prescription>
B) Mass%
Squalane 5.0
Dimethicone 5.0
Stearyl stearate 4.0
Behenyl alcohol 5.0
Cetyl alcohol 1.0
Glyceryl stearate 2.0
POE (40) stearate 1.0
Butylparaben 0.1
B)
1,3-butanediol 9.0
Glycerin 1.0
Hydroxymethylcellulose 0.4
Methylparaben 0.2
Water remaining

<Cream B prescription>
B) Mass%
Squalane 7.0
Dimethicone 1.0
Stearyl stearate 4.0
Behenyl alcohol 5.0
Cetyl alcohol 1.0
Glyceryl stearate 1.8
POE (40) stearate 1.2
Butylparaben 0.1
B)
1,3-butanediol 5.0
Glycerin 10.0
Hydroxymethylcellulose 0.4
Methylparaben 0.2
Water remaining

Comparative example

<Comparison between the invention of the present application and a general measurement method>
Table 3 shows the results of a comparative study on the relationship between the results of the inventions of Examples 2, 3 and 5 and the sensory evaluation, and the relationship between the sensory evaluation by a commonly used measuring instrument. From Table 3, the present invention has better consistency with the sensory evaluation than the general measurement method, and from this, the discrimination method of the present invention has the effect of discriminating the skin characteristics that are strongly felt and recognized by the subject. I understand that.
<Evaluation methods and measuring instruments>
In the same manner as in Examples 2, 3, and 5, parameters corresponding to sensory evaluation were obtained using the following equipment, and correlation analysis and significance test were performed, respectively.
・ C + K company cut meter MPA580 (registered trademark)
・ Kato Tech's friction tester KES-SE

＊＊＊ Ｐ＜０．００１
＊＊ Ｐ＜０．０１
＊ Ｐ＜０．０５
− Ｐ＜０．１０

*** P <0.001
** P <0.01
* P <0.05
− P <0.10

  By using the skin property discrimination method and the discrimination system of the present invention, it is possible to provide a discrimination result of skin properties such as “softness”, “elasticity” or “smoothness” that can be felt and recognized by humans. By using such results, it can be used effectively and effectively, for example, at a store or a department store, for counseling of skin and beauty, selection of cosmetics, and the like.

It is a schematic block diagram of a skin characteristic discrimination system. It is a figure which shows the amount of displacements of the amount of retraction of a spherical body, and the amount of rebounds. It is a figure which shows the relationship between the displacement amount of a spherical body, and time. It is a scatter diagram which shows the relationship between the amount of sphere penetration and skin sensory evaluation (softness). It is a scatter diagram which shows the relationship between the amount of rebounds of a sphere, and skin sensory evaluation (elasticity). It is a figure which shows the influence on the rolling speed of cream A, B. FIG.

1 Sphere 2 Fixing means 3 High-speed camera 4 Analysis / display means H Drop height

Claims (5)

A method for distinguishing skin characteristics, wherein a change (displacement) of a sphere on a skin surface is photographed with a high-speed camera, and the photographed sphere is subjected to image processing analysis. 2. The method for distinguishing skin characteristics according to claim 1, wherein the skin characteristics are determined by a correlation between a sensory evaluation value of a surface condition of the skin and a characteristic value of a sphere on the skin surface. 3. The method for distinguishing skin characteristics according to claim 1, wherein the skin characteristics are selected from "softness" or "elasticity". The method for distinguishing skin characteristics according to claim 1 or 2, wherein the skin characteristics are "smoothness". A sphere to be dropped on the skin surface, a fixing means for holding the sphere, a high-speed camera for photographing a sphere change after the sphere is dropped, and an analysis / display means for processing, analyzing, and displaying an image photographed by the high-speed camera A system for distinguishing skin characteristics.

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