JP4159515B2 - Method for evaluating the degree of human hair - Google Patents

Description

  The present invention relates to a method for evaluating the degree of human hair.

  Hair shape or hair style is one of the factors that determine a person's first impression, and various research and development have been conducted from a cosmetic and psychological viewpoint. In addition, the shape of hair is an important subject of evaluation and research in the fields of forensic medicine and anthropology. In these research and development, when analyzing, defining, classifying and evaluating the actual shape of hair, it is necessary to quantify the hair shape objectively and quantitatively. Furthermore, it is necessary not only to evaluate the shape of each individual hair, but also to evaluate the degree of individual hair and digitize it as a unique value for that person. Conventionally, methods for evaluating the shape of hair include a hair cross-section ratio measurement method, an end-to-end distance ratio measurement method, and a curl diameter measurement method, as shown below.

  In the hair cross-section ratio measurement method, the minimum diameter a and the maximum diameter b in the hair cross section are measured from the viewpoint that the hair cross section is closer to a perfect circle, and the straight hair is measured. / B) × 100 (%) (see Patent Document 1 and Non-Patent Document 1). In the end-to-end distance ratio measurement method, the distance a from the tip to the end of the hair in a normal state where the hair is curled, and the distance b from the tip to the end of the hair in a state where the hair is linearly stretched are measured. The hair shape is evaluated as a / b (see Non-Patent Document 1). The curl diameter measurement method measures the curl diameter (curvature radius, curvature, etc.) at an arbitrary point on the hair and evaluates the shape of the hair (see Non-Patent Document 1).

JP 2002-111284 A D. Hrdy, Am. J. et al. Phys. Anthrop. , 39, p7, 1973

  However, conventional methods for evaluating the shape of hair have the following problems. In the hair cross-section ratio measurement method, when the cross-section of the hair to be measured is not perpendicular to the hair axis, it is not possible to obtain an accurate roundness, and even if the roundness is close to 100 (%), it is bent. In this method, the shape of the hair could not be accurately quantified. The shape of the hair evaluated by the end-to-end distance ratio measurement method or the curl diameter measurement method reflects the shape in a limited situation such as when the hair has no inflection point or when the hair is bent to some extent. Although it showed an accurate value, it did not show an accurate value when the hair had a three-dimensionally complicated shape, and it was not a standard for broadly classifying and evaluating human hair.

  In addition, any of the conventional methods for evaluating the shape of hair is a method for evaluating the shape of each individual hair, and it is an accurate criterion to evaluate the degree of individual hair using these methods. Because there was no, it was not possible.

  Accordingly, an object of the present invention is to objectively and quantitatively quantify the shape of a complex and diverse human hair, and to use the shape as an accurate reference, and a human hair shape evaluation method, An object of the present invention is to provide a method for evaluating the degree of human hair that can digitize the individual's unique hair level based on the hair shape evaluation method and use the value as an accurate reference.

  The present inventors obtain a three-dimensional point cloud image of human hair and represent it as a three-dimensional hair curve, and tangent vectors, curvature vectors, or adjacent to each other on the three-dimensional hair curve at arbitrary equal intervals. When drawing a normal vector of a plane formed by two tangent vectors, the value obtained based on the angle between adjacent tangent vectors, adjacent curvature vectors, or adjacent normal vectors is the hair It was found that this is a method that can objectively and quantitatively quantify the actual shape.

  Further, the present inventors obtained at least the subject's hair from a predetermined part of the head including the front hair part, the temporal part and the neck part, and evaluated the shape according to the human hair shape evaluation method. It was found that these values are values that can accurately represent an individual's inherent comb hair level based on actual conditions.

  The present invention has been made based on the above knowledge, a first step of collecting hair from a predetermined part of the subject's head, a second step of obtaining a three-dimensional point cloud image of the hair shape, and the three-dimensional A third step of creating a three-dimensional hair curve based on a point cloud image; and (a) the three-dimensional hair on the calculation point P with respect to a plurality of calculation points P determined at arbitrary equal intervals on the three-dimensional hair curve A tangent vector Vt in contact with the curve, (b) a curvature vector Vc in contact with the three-dimensional hair curve on the calculation point P, (c) a normal vector Vn of a plane formed by two adjacent tangent vectors, The hair shape F is calculated based on the angle θt between adjacent tangent vectors Vt, the angle θc between adjacent curvature vectors Vc, or the angle θn between adjacent normal vectors Vn. Step, in which to achieve the above object by providing a curly degree evaluation method including persons with and.

  According to the present invention, the human hair shape F is used as an accurate reference by quantifying the human hair shape F based on the three-dimensional change angle θ. Can do. In addition, based on the human hair shape evaluation method, by evaluating the shape of the hair collected from a predetermined part of the subject's head, it is possible to obtain an individual's unique comb hair degree, which can be used as an accurate reference. can do.

  Hereinafter, the most preferable embodiment of the method for evaluating the degree of human hair of the present invention will be described in detail. As shown in FIGS. 2 to 4, the method for evaluating the degree of human hair of the present embodiment includes a first step of collecting hair H from a predetermined part of the subject's head and a three-dimensional point cloud image of the shape of the hair H. A second step of obtaining a three-dimensional hair curve h based on the three-dimensional point cloud image, and a plurality of calculation points P determined at equal intervals on the three-dimensional hair curve h, (A) a tangent vector Vt tangent to the three-dimensional hair curve h on the calculation point P, (b) a curvature vector Vc tangent to the three-dimensional hair curve on the calculation point P, or (c) two tangent vectors adjacent to each other. The normal vector Vn etc. of the plane formed by is drawn, the angle θt between adjacent tangent vectors Vt, the angle θc between adjacent curvature vectors Vc, or the angle between adjacent normal vectors Vn θn etc. Zui by a method comprising a fourth step of determining a shape F of the hair, and. First, a hair shape measuring system that realizes such a method for evaluating the degree of human hair will be described with reference to FIG.

  As shown in FIG. 1, the hair shape measurement system 1 of the present embodiment includes a three-dimensional digitizer 2, a digitizer body device 3, an analysis device 4, a temperature / humidity meter 5, a hair fixture 6, a vibration isolation plate 7, and a windshield case 8. Etc. The three-dimensional digitizer 2 and the analysis device 4 are each electrically connected to the digitizer main body device 3. The digitizer body device 3 is configured to transmit the three-dimensional point cloud image acquired by the three-dimensional digitizer 2 to the analysis device 4. The analysis device 4 has a built-in memory in which a predetermined analysis program is recorded. The analysis device 4 is configured to execute predetermined steps in the shape evaluation method based on the three-dimensional point cloud image received from the digitizer body device 3 in accordance with an instruction from the analysis program (details will be described later). ).

  The thermohygrometer 5 is electrically connected to the analysis device 4 and transmits temperature and humidity information at the time of measurement. The hair fixture 6 supports the hair H to be measured in the measurable area of the three-dimensional digitizer 2. The vibration isolation plate 7 is for reducing vibration generated by the operation of the three-dimensional digitizer 2 and preventing the hair H supported by the hair fixing tool 6 from vibrating. The windshield case 8 covers the hair fixing tool 6, the three-dimensional digitizer 2, and the like, and prevents the hair H supported on the hair fixing tool 6 from vibrating due to the influence of the outside environment such as wind.

  Next, the method for evaluating the human hair level according to this embodiment will be described. In the first step, as shown in FIGS. 5A to 5C, hair H is collected from a predetermined part of the head of the subject. Examples of the predetermined part of the head include a front hair part, a top part, a temporal part, a occipital part, and a neck part. It is the front hair part, the temporal part, and the neckline part that remarkably represent the individual's unique comb hair degree based on the actual situation. Therefore, the predetermined part of the head from which the hair H is collected includes at least a front hair part, a temporal part, and a neck part. Further, from the viewpoint of setting a person's comb hair level to a value close to sensory evaluation, it is preferable to collect hair H from a predetermined part of the head, particularly from a part exposed on the surface. There is no particular limitation on the number of hairs H to be collected, but in order to obtain an individual's inherent comb hair degree, it is preferable that the number is 1 to 2000, particularly 2 to 100, respectively, from a predetermined part of each head. 5 to 10,000, particularly 10 to 500 is preferable.

  In the second step, as shown in FIG. 1 or FIG. 2, a predetermined number (for example, 50) of hairs H are measured, and one hair H selected from these is attached to the hair fixing tool 6, and the tertiary Place in the measurable area of the original digitizer 2. A three-dimensional point cloud image of the hair H is acquired by the three-dimensional digitizer 2. This three-dimensional point cloud image is transmitted to the analysis device 4 via the digitizer body device 3.

  In the third step, as shown in FIG. 3, the analysis device 4 creates a NURBS curve along the shape of the original hair H from the three-dimensional point cloud image of the hair H in the xyz space coordinates, The hair curve is h (three-dimensional fiber curve).

  In the fourth step, as shown in FIG. 4, the calculation point P0 of the starting point is taken at one end on the hair root side of the three-dimensional hair curve h, and m calculation points P1 are taken every arbitrary curve distance q (for example, 1 mm). ~ Pm is defined along the three-dimensional hair curve h. The number m of calculation points is a number determined by the length of the three-dimensional hair curve h and the curve distance q between the calculation points. Then, the next operation (a), (b) or (c) is performed.

(A) For each of the measurement points P0, P1, P2, P3, P4,..., Pm, tangent vectors Vt0, Vt1, Vt2, Vt3, Vt4,.
(B) For each measurement point P0, P1, P2, P3, P4,..., Pm, draw curvature vectors Vc0, Vc1, Vc2, Vc3, Vc4,.
(C) For the tangent vectors Vt0, Vt1, Vt2, Vt3, Vt4,..., Vtm, the normal vectors Vn0, Vn1, Vn2, Vn3, Vn4,. m-1) is drawn.

  In (a), for two tangent vectors Vt0 and Vt1 adjacent to each other, one plane passing through them is defined as xyz space coordinates, and an angle θt1 between the tangent vectors (Vt0 and Vt1) is obtained on this plane. . Thereafter, in the same manner as described above, the angle between the vectors θt2, θt3, θt4 between the tangent vectors (Vt1, Vt2), (Vt2, Vt3), (Vt3, Vt4),. ,..., Θtm are obtained sequentially. The angles θt1, θt2,..., Θtm between the vectors obtained here are absolute values of 0 ° to 180 °.

  In (b), for two curvature vectors Vc0 and Vc1 adjacent to each other, one plane passing through these is defined as xyz space coordinates, and an angle θc1 between the curvature vectors (Vc0 and Vc1) is obtained on this plane. . Thereafter, in the same manner as described above, the angles between the vectors θc2, θc3, θc4 between the curvature vectors (Vc1, Vc2), (Vc2, Vc3), (Vc3, Vc4),. ..., Θcm is obtained sequentially. The angles θc1, θc2,..., Θcm between the vectors obtained here are absolute values of 0 ° to 180 °.

  In (c), for two normal vectors Vn0 and Vn1 adjacent to each other, one plane passing through them is defined as xyz space coordinates, and an angle θn1 between the normal vectors (Vn0 and Vn1) is defined on this plane. Ask for. Thereafter, in the same manner as described above, between the normal vectors (Vn1, Vn2), (Vn2, Vn3), (Vn3, Vn4),..., {Vn (m-2), Vn (m-1)} The angles θn2, θn3, θn4,..., Θn (m−1) are obtained sequentially. The angles θn1, θn2,..., Θn (m−1) between the vectors obtained here are absolute values from 0 ° to 180 °.

In (a), the angles θt1, θt2,..., Θtm between vectors, the distance between points q, and the number m of calculation points are substituted into the following equation (1), and the shape F of the hair is changed with respect to the hair H. Calculated as the change angle per unit length. The hair shape F obtained here is an index representing the degree of bending of the hair H.
F = (θt1 + θt2 +... + Θtm) / (q × m) (1)

In (b), the angles θc1, θc2,..., Θcm between vectors, the distance between points q, and the number m of calculation points are substituted into the following equation (2), and the hair shape F Calculated as the change angle per unit length. The hair shape F obtained here is an index representing the degree of twist of the hair H.
F = (θc1 + θc2 + ... + θcm) / (q × m) (2)

Furthermore, in (c), the angles θn1, θn2,..., Θn (m−1) between the vectors, the distance between points q, and the number m of calculation points are substituted into the following equation (3) to obtain the hair shape F For the hair H as a change angle per unit length. The hair shape F obtained here is an index representing the degree of twist of the hair H.
F = {θn1 + θn2 +... + Θn (m−1)} / {q × (m−1)} (3)

  Thereafter, in any of the cases (a) to (c), the second hair H is a measurement object, and the 3D point cloud image is obtained based on the 2nd step of obtaining the 3D point cloud image and the 3D hair image based on the 3D point cloud image. A third step for creating the curve h and a fourth step for obtaining the hair shape F are performed. Such measurement of the hair shape F is repeated for the remaining hair H.

  Finally, the average value of the hair shape F is obtained for all the hair H collected from the subject. This average value is an index representing the degree of human hair.

  The hair shape F thus obtained is the degree that the shape of the hair H is objectively and quantitatively quantified by averaging the three-dimensional change angle θ per unit length of the hair H. is there. In addition, the degree of human comb hair obtained in this way is a value that accurately reflects the actual state of the comb hair obtained by sensory evaluation, for example, in the technical field of hair research, etc. It is an accurate standard when analyzing the actual condition of the degree, defining it, and carrying out classification and evaluation.

  For example, in the technical field of hair research, in the development of substances that change the shape of hair, by comparing the values of the shape F before application of the substance and the form F after application of the substance, Screen effective substances that change shape.

  For example, in the technical field of psychological research, when examining the effect of hair shape or styling on psychology, the effect of the hair shape F or the human hair level is used as an index as a reference. Try to evaluate.

  For example, in the technical field of forensic research, it can be applied to identification and classification of individuals, criminal investigations, etc. using objective and quantitatively quantified hair shape F or human hair level as a standard index. To go.

  Also, for example, in the technical field of anthropological research, the anthropological characteristics are evaluated by the shape of the hair H, and in the field to classify, objective, regardless of rough classification such as Asian, white, black, etc. More detailed classification and evaluation are performed using quantitatively digitized hair shape F or human hair level as a reference index.

  As described above, according to the present embodiment, the shape of the human hair H is objectively determined by averaging the three-dimensional change angle θ per unit length of the hair H with respect to the shape F of the hair H. In addition, the hair is sampled from a predetermined part of the subject's head, and the shape of the hair is measured to obtain the individual hair level. In technical fields such as academic research, forensic research, and anthropological research, the shape F of hair or the degree of human hair can be used as an accurate reference.

  In particular, in the case of this embodiment, since the shape F of the hair H is represented by the three-dimensional change angle θ based on the three-dimensional hair curve h that accurately reproduces the actual hair shape, such a shape F is used. By doing so, the actual shape of the hair H can be expressed as an accurate measure in a three-dimensional space, compared to the case where an evaluation method such as a two-dimensional end-to-end distance ratio measurement method or a curl diameter measurement method is used. .

  In addition, according to the present embodiment, since the target portion from which the hair is to be collected is specified as the predetermined head portion, the hair shape F can be obtained for each predetermined head portion, and as a result, the comb hair for each predetermined head portion. An accurate reference can be obtained for the degree.

The present invention is not limited to the above-described embodiment, and various changes can be made. For example, if the shape F of the human hair is obtained based on the angle θ between the vectors V adjacent to each other, it is not limited to the above formulas (1) to (3). It may be determined according to 4), (5), (6) or the like.
F = (1 / m−1) {(θt1−Θt) ² + (θt2−Θt) ² +... + (Θtm−Θt) ² } Equation (4)
F = (1 / m-1 ) {(θc1-Θc) 2 + (θc2-Θc) 2 + ... + (θcm-Θc) 2} ··· Equation (5)
F = (1 / m−2) [(θn1−Θn) ² + (θn2−Θn) ² +... + {Θn (m−1) −Θn} ² ] (6)
(However, Θt, Θc, and Θn represent the average value of the angles θ between the vectors V adjacent to each other.)

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited to such examples.

[Example 1]
[1] Measurement accuracy verification and its verification method 11 hairs having various shapes were used as standard hair for measurement accuracy verification, and the measurement accuracy was verified for the hair shape evaluation method of this embodiment. A gonio-rotating device was attached to the hair fixture 6 to support standard hair. In gonio, standard hair is -15 ° to 15 ° (7 points) at 5 ° intervals in the same direction as the 3D digitizer axis, and -15 ° to 15 ° at 5 ° intervals in the direction orthogonal to the 3D digitizer axis. The first step processing was performed while changing to (7 points) to obtain a three-dimensional point cloud image. Moreover, the process of the 1st step was performed, rotating a standard hair to 0 degrees-360 degrees (13 points) at intervals of 30 degrees using the rotation device, and the three-dimensional point cloud image was acquired. The analysis process of the 2nd step and the 3rd step was performed with respect to these three-dimensional point cloud images, and the measurement accuracy with respect to the way of supporting the hair was verified. Subsequently, each standard hair was repeatedly measured 10 times from the place where it was supported on the hair fixing device 6, and the accuracy of the repeated measurement was performed. Table 1 shows the measurement accuracy test results for the hair support method and the repeat measurement accuracy test results.

[2] Measurement accuracy test results As shown in Table 1, the variation coefficient (CV value) is less than 15% for the measurement accuracy test results for the hair support method and the repeat measurement accuracy test results. Thus, it was revealed that the shape of the standard hair can be accurately measured by using the hair shape evaluation method of the present embodiment.

[Example 2]
[1] Standard hair shape measurement and method The relationship between the hair shape F of the hair shape evaluation method of the present embodiment and the actual shape of the hair shape obtained by sensory evaluation was investigated, and the hair of the present embodiment The accuracy of the shape evaluation method was investigated. The shape F of 11 standard hairs having various shapes was determined according to the formula (1) in the hair shape evaluation method of the present embodiment. On the other hand, with respect to these 11 standard hairs, 6 expert panelists scored the degree of apparent bending with numerical values of 1 (low bending degree) to 11 (high bending degree), and calculated the average value. The relationship between the standard hair shape F and the average bending degree score is shown in FIG.

[2] Measurement Results of Standard Hair Shape As shown in FIG. 6, it is clear that there is a positive correlation between the hair shape F of the hair shape evaluation method of this embodiment and the average score of the degree of bending by appearance. Became. Accordingly, if the hair shape F of the hair shape evaluation method of the present embodiment is used as a reference, the actual shape of the hair shape can be quantified more objectively, quantitatively, and accurately.

Example 3
[1] Simulation Evaluation The hair shape evaluation method A of the present embodiment was compared and evaluated by the conventional end-to-end distance ratio measurement method B and the conventional minimum curl diameter measurement method C by simulation analysis. As described above, the end-to-end distance ratio measurement method B includes the distance a from the tip of the hair to the end in a normal state where the hair is curled, and the distance from the tip of the hair to the end in a state where the hair is linearly stretched. This is a method of measuring the distance b and obtaining the hair shape as a / b. The minimum curl diameter measuring method is a method for obtaining the hair shape as the minimum curl diameter by comparing the hair with a curvature radius chart.

[2] Simulation evaluation method A pseudo hair curve in which a plurality of arcs having a constant radius of curvature r (0.1 cm, 0.2 cm,..., 1 cm, 2 cm,. In the hair shape evaluation method A of the present embodiment, the hair shape F was determined from the pseudo hair curve according to the equation (1). In the end-to-end distance ratio measurement method B, the end-to-end distance ratio was determined, and in the minimum curl diameter measurement method C, the minimum curl diameter was determined.

[3] Simulation evaluation results The following (1) to (3) were clarified as an analysis result of the simulation evaluation.
(1) The end-to-end distance ratio obtained by the end-to-end distance ratio measuring method B correlates with the hair shape F obtained by the shape evaluation method A for a pseudo hair curve having no inflection point (FIG. 7). For a pseudo hair curve having an inflection point, a result smaller than the hair shape F obtained by the shape evaluation method A is shown (FIG. 8).
(2) Human hair is roughly divided into “straight hair”, “almost straight hair (weak wave hair)”, “wave hair”, “curl hair (strong wave hair)”, and “curly hair” according to the degree of comb hair. However, “curly hair” and “curled hair (strong wave hair)” are often composed of hair having an inflection point. Therefore, it should be judged that the hair having an inflection point has a large degree of comb hair, and the end-to-end distance ratio obtained by the end-to-end distance ratio measuring method B cannot be accurately evaluated.
(3) The minimum curl diameter obtained by the minimum curl diameter measuring method C cannot be accurately evaluated with respect to the pseudo hair curve (FIG. 9).

  From the above-mentioned points, the hair shape evaluation method A of the present embodiment is quantified in accordance with the actual situation compared to the conventional end-to-end distance ratio measurement method B or the conventional minimum curl diameter measurement method C. It became clear that it was suitable for.

Example 4
[1] Analysis and Method Related to Sensory Evaluation The relationship between the person's combing hair degree evaluation method of the present embodiment and the actual condition of the combing hair degree by the sensory evaluation was investigated. For 19 subjects A to T, 55 hairs of about 4 cm length exposed on the surface of each part (11 places) of the head were collected from each part, 55 in total. As shown in FIGS. 10 (a) to 10 (c), the breakdown of each part of the head is the front hair parts 1 to 3, the temporal parts 4 to 7, the occipital part 8, and the neck parts 9 to 11. For each of 55 hairs of 19 subjects of subjects A to T, the hair shape F is measured according to the formula (1) in the hair shape evaluation method of the present embodiment, the average value is calculated, and the individual's comb hair degree Asked.

On the other hand, 20 head photographs of subjects A to T were taken, respectively, and using these photographs and 55 hairs collected, 6 expert panelists set the degree of bending to 1 (the degree of bending is small) to 19 ( The average value was calculated by scoring with a numerical value of the degree of bending (high degree of bending), and was used as a score of comb hair by sensory evaluation.
FIG. 11 shows the relationship between the individual comb hair degree and the comb hair degree score by sensory evaluation.

[2] Results of Analysis Related to Sensory Evaluation As shown in FIG. 11, it is clear that there is a positive correlation between the degree of human hair in the human hair evaluation method and the actual state of the hair by sensory evaluation. became. Thus, if the human combing hair degree of the human hair comb evaluation method of the present embodiment is used as a reference, the actual state of the individual combing hair degree can be quantified more objectively, quantitatively and accurately. Is possible.

  The method for evaluating the degree of human hair of the present invention includes, for example, a technical analysis field of hair research such as actual condition analysis survey of hair shape, classification / evaluation of hair shape, development of substances that change hair shape, etc. Technical field of psychological research such as investigation of the relationship between the shape of human and psychology, for example, technical field of forensic research such as identification and classification of individuals, criminal investigation, etc., for example, hair shape and human evolution, movement, distribution, etc. It can be widely used in the technical field of anthropological research such as related research.

It is a figure which shows schematic structure of the hair shape measuring system 1 of this embodiment. It is a figure used for description of the 2nd step of the person's comb hair evaluation method of this embodiment. It is a figure used for description of the 3rd step of the person's comb hair degree evaluation method of this embodiment. It is a figure used for description of the 4th step of the person's comb hair evaluation method of this embodiment. It is a figure which shows the head predetermined | prescribed site | part which extract | collects hair in the 1st step of the person's comb hair evaluation method of this embodiment. It is a graph which shows the relationship between the shape F of the standard hair of Example 2, and an average bending degree score. It is a graph which shows the analysis result (there is no inflection point) of simulation evaluation of Example 3. It is a graph which shows the analysis result (with an inflection point) of the simulation evaluation of Example 3. 10 is a graph showing an analysis result (minimum curl diameter) of simulation evaluation of Example 3. It is a figure which shows the head predetermined | prescribed site | part which extract | collects the hair of Example 4. FIG. It is a graph which shows the relationship between the individual's comb hair degree of Example 4, and the comb hair score by sensory evaluation.

Explanation of symbols

F Hair shape H Hair h Three-dimensional hair curve m Number of calculation points P Calculation points q Curve distance between calculation points Vt Tangent vector Vc Curvature vector Vn Normal vector of a plane formed by two adjacent tangent vectors θt An angle between two adjacent tangent vectors θc An angle between two adjacent curvature vectors θn An angle between two adjacent normal vectors

Claims (6)

A first step of collecting hair from a predetermined part of the subject's head, a second step of obtaining a three-dimensional point cloud image of the hair shape, and a third step of creating a three-dimensional hair curve based on the three-dimensional point cloud image (A) a tangent vector Vt tangent to the three-dimensional hair curve on the calculation point P, and (b) a calculation point P on the three-dimensional hair curve. (C) A normal vector Vn of a plane formed by two adjacent tangent vectors is drawn, and an angle θt between adjacent tangent vectors Vt is adjacent to each other. angle θc between the curvature vector Vc, or based on one of the angle θn between the normal vector Vn adjacent to each other, a fourth step of determining a shape F of the hair, city only including, the hair Assessing the curly degree of humans by Jo F, human habit degree evaluation method.   2. The method for evaluating a human hair level according to claim 1, wherein in the first step, the predetermined part of the head includes at least a front hair part, a temporal part, and a neck part. In the fourth step, the hair shape F of the human hair according to claim 1 or 2, wherein the hair shape F is calculated as a change angle per unit length according to the following formula (1), and represents the degree of bending of the hair: Evaluation methods.
F = (θt1 + θt2 +... + Θtm) / (q × m) (1)
(However, when the calculation point of the starting point on the three-dimensional hair curve is P0 and the number of calculation points other than P0 is m (1 ≦ k ≦ m), q is the calculation point Pk on the three-dimensional hair curve. −1 and Pk, θtk is the absolute value of the angle between the tangent vectors Vtk−1 and Vtk for the calculation points Pk−1 and Pk.) In the fourth step, the hair shape F of the human hair according to claim 1 or 2, wherein the hair shape F is calculated as a change angle per unit length according to the following formula (2) and represents the degree of twist of the hair: Evaluation methods.
F = (θc1 + θc2 + ... + θcm) / (q × m) (2)
(However, when the calculation point of the starting point on the three-dimensional hair curve is P0 and the number of calculation points other than P0 is m (1 ≦ k ≦ m), q is the calculation point Pk on the three-dimensional hair curve. −1 and Pk, θck is the absolute value of the angle between the curvature vectors Vck−1 and Vck for the calculation points Pk−1 and Pk.) In the fourth step, the hair shape F of the human hair according to claim 1 or 2, wherein the hair shape F is calculated as a change angle per unit length according to the following formula (3) and represents the degree of twist of the hair: Evaluation methods.
F = {θn1 + θn2 +... + Θn (m−1)} / {q × (m−1)} (3)
(However, when the calculation point of the starting point on the three-dimensional hair curve is P0 and the number of calculation points other than P0 is m (1 ≦ k ≦ m), q is the calculation point Pk on the three-dimensional hair curve. −1 and Pk, and θnk is a plane formed by the normal vector Vnk−1 of the plane formed by the two tangent vectors Vtk−1 and Vtk, and the plane formed by the two tangent vectors Vtk and Vtk + 1. (The absolute value of the angle between the normal vectors Vnk of   6. The method for evaluating a human hair level according to any one of claims 1 to 5, wherein, in the second step, the three-dimensional point cloud image of the hair is acquired using a three-dimensional digitizer.

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