EP4296024A1

EP4296024A1 - Electric shaver

Info

Publication number: EP4296024A1
Application number: EP22755940.8A
Authority: EP
Inventors: Yoshiaki Kanamori
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2021-02-16
Filing date: 2022-02-02
Publication date: 2023-12-27
Also published as: WO2022176619A1; CN116829317A; JP2022124568A; EP4296024A4

Abstract

The present disclosure provides an electric razor that accurately detects a property of a hair in the case of a white hair. Electric razor (100) according to the present disclosure is electric razor (100) that includes grip (110) and head part (120) connected to one end of grip (110). The electric razor includes imaging device (131) that images a part near a skin with which shaving unit (121) comes into contact, illumination device (160) configured to irradiate a region imaged by imaging device (131) with light rays of different spectra, and an image processing device that processes an image acquired from imaging device (131). The image processing device includes an imaging control unit that controls illumination device (160) and imaging device (131) to cause the region to be imaged by being individually irradiated with the light rays of the different spectra, and a property information generation unit that generates property information indicating a property of the hair based on the image imaged by imaging device (131).

Description

TECHNICAL FIELD

The present disclosure relates to an electric razor for cutting a hair such as a beard.

BACKGROUND ART

In the related art, a shaving guidance system that comprises an imaging device that records an image of a body part of a user, and obtains a local hair growth direction based on an imaged image, and gives, to the user, an instruction about a direction and a place in which a shaving device is to be moved on the body in accordance with the obtained hair growth direction has been proposed (see, for example, PTL 1).

Citation List

Patent Literature

PTL 1: Japanese Translation of PCT International Application No. 2016-534806

SUMMARY OF THE INVENTION

Technical problem

However, in a system of the related art, in a case where a color tone difference between a skin and a hair is small, for example, a white hair in a person whose skin color is white, a color tone difference between the skin and the hair is small. Thus, it is difficult to separate the skin and the hair by image processing, and it is difficult to acquire information on a property of the hair.
The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide an electric razor capable of detecting a property of a hair having a small color tone difference from a skin.

Solution to problem

In order to achieve the above object, an electric razor of an aspect of the present disclosure is an electric razor that includes a grip to be gripped by a user, and a head part having a shaving unit for cutting a hair, the head part being connected to an end of the grip. The electric razor includes an imaging device that images a part near a skin with which the shaving unit comes into contact, an illumination device that is configured to irradiate a region imaged by the imaging device with light rays of different spectra, and an image processing device that processes an image acquired from the imaging device. The image processing device includes an imaging control unit that controls the illumination device and the imaging device to cause the region to be imaged by being individually irradiated with the light rays of the different spectra, and a property information generation unit that generates property information indicating a property of the hair based on the image imaged by the imaging device.

Advantageous effect of invention

According to the electric razor of the present disclosure, the skin and the hair are effectively separated from each other and the property of the hair can accurately be detected by individually irradiating the hairs with the light rays of the different spectra.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view illustrating an electric razor according to an exemplary embodiment.
Fig. 2 is a perspective view illustrating a head part of the electric razor according to the exemplary embodiment.
Fig. 3 is a graph representing a relationship between a wavelength of light applied to a skin and a reflection characteristic.
Fig. 4 is a block diagram illustrating a functional unit of an image processing device of the electric razor according to the exemplary embodiment.
Fig. 5 is a block diagram illustrating a functional unit of another example of the image processing device of the electric razor according to the exemplary embodiment.

DESCRIPTION OF EMBODIMENT

Hereinafter, exemplary embodiments of an electric razor according to the present disclosure will be described with reference to the drawings. Note that the following exemplary embodiments are examples for describing the present disclosure, and are not intended to limit the present disclosure. For example, a shape, a structure, a material, a component, a relative positional relationship, a connection state, a numerical value, a mathematical expression, the contents of each step and the order of individual steps in a method, and the like described in the following exemplary embodiments are merely examples, and may include the contents that are not described below. In addition, geometric expressions such as parallel and orthogonal may be used, but these expressions do not indicate mathematical strictness, and include substantially acceptable errors, deviations, and the like. In addition, expressions such as simultaneous and identical include substantially acceptable ranges.
In addition, the drawings are schematic views in which emphasis, omission, and ratio adjustment are appropriately performed in order to describe the present disclosure, and may be different from actual shapes, positional relationships, and ratios.
In addition, hereinafter, a plurality of technical ideas may be comprehensively described as one exemplary embodiment. In addition, some of the contents to be described below are described as optional components related to the present disclosure.
Fig. 1 is a perspective view illustrating electric razor 100 according to the exemplary embodiment. Fig. 2 is a perspective view of head part 120 of electric razor 100. Note that electric razor 100 has portions that include a rounded edge, and recesses and protrusions for preventing slippage, but these portions are not illustrated.
Electric razor 100 is a device that cuts and removes a hair such as a beard by using an electric blade, and includes grip 110, head part 120, imaging device 131, illumination device 160, and image processing device 150 (not illustrated in Fig. 1. see Figs. 4 and 5). In the present exemplary embodiment, electric razor 100 includes notification device 140.
Grip 110 is a portion gripped by a user when electric razor 100 is used. In the case of the present exemplary embodiment, grip 110 also functions as a housing for accommodating image processing device 150, a controller that controls the drive of a shaving blade, a battery, and the like. Power supply switch 111 for turning on and off a power supply, input button 112 for receiving an input from the user, and the like are provided on an outer surface of grip 110.
Head part 120 includes shaving unit 121 having a blade for cutting a hair, and is a member connected to one end of grip 110. In the case of the present exemplary embodiment, head part 120 is relatively operably connected to grip 110. An operation direction of head part 120 is not particularly limited, but head part 120 is swingable in a circumferential direction with each of a front-back direction (X-axis direction in the drawing), a width direction Y (Y-axis direction in the drawing), and an up-down direction (Z-axis direction in the drawing) as an axial center.
Shaving unit 121 includes a plurality of (four in the present exemplary embodiment) first outer blades 122 in the front-back direction, each of which is semicylindrical and mesh-shaped, extends in the width direction, and has through holes, and second outer blade 123 which has slit-shaped through-holes and is disposed between first outer blades 122. First outer blades 122 and second outer blade 123 are attached to head frame 124, and shaving unit 121 is detachably attached to head base body 125.
First inner blades (not illustrated) provided to correspond to first outer blades 122 and a second inner blade (not illustrated) provided to correspond to second outer blade 123 are disposed inside head part 120, and an inner blade drive device for causing each of the first inner blades and the second inner blade to reciprocate in the width direction (Y-axis direction in the drawing) is provided. The inner blade drive device vibrates the first inner blades and the second inner blade, and thus, a hair inserted into the through-holes of first outer blade 122 and second outer blade 123 is cut between first inner blades and second inner blade that vibrate.
Imaging device 131 is a device that images a part near the skin with which shaving unit 121 comes into contact. In the case of the present exemplary embodiment, imaging device 131 has an angle of view at which, in a state where shaving unit 121 is brought into contact with the skin, a skin having a length corresponding to the entire of first outer blades 122 and second outer blade 123, which are the outer blades in the front-back direction (X-axis direction in the drawing) and a skin having a length corresponding to the entire width (Y-axis direction in the drawing) of first outer blade 122 in the width direction (Y-axis direction in the drawing) can be imaged at a time. Accordingly, states of a hair and a skin immediately before and after shaving can be accurately imaged.
A type of imaging device 131 is not particularly limited, and for example, a so-called digital camera including an optical system including a lens and the like and an imaging element that converts an image formed by the optical system into an electrical signal can be exemplified. In the case of the present exemplary embodiment, imaging device 131 can image any of light rays of different spectra emitted by illumination device 160.
Imaging device 131 is fixed to head base body 125 of head part 120, and imaging device 131 also operates together with an operation of head part 120 for grip 110. Accordingly, a distance between the skin and imaging device 131 can be stabilized even during shaving by electric razor 100, and a clearer image can be imaged. Specifically, as illustrated in Fig. 2, imaging device 131 is attached to a central portion of substrate 133 protruding forward from a front surface (X-side in the drawing) of head base body 125 in the width direction (Y-axis direction in the drawing). According to this, since imaging device 131 does not become an obstacle when head frame 124 is attached or detached, such an attachment is preferable. In addition, illumination device 160 such as a light emitting diode (generally referred to as "LED") that illuminates the skin within the angle of view of imaging device 131 is attached to substrate 133. Substrate 133, imaging device 131, and illumination device 160 are covered with cover 134.
Illumination device 160 is a device capable of irradiating a region imaged by imaging device 131 with light rays of different spectra. Each spectrum with which illumination device 160 irradiates a predetermined region is not particularly limited, but, for example, illumination device 160 including light sources having maximum peak wavelengths of emitted light rays different from each other can be exemplified. In addition, the light source included in illumination device 160 may be a light source that emits light of substantially a single wavelength, such as an LED, or may be a light source that includes an element that emits excitation light, such as an LED or a laser beam, and a wavelength conversion substance that converts a wavelength of the light emitted from the element. In the case of the present exemplary embodiment, as illustrated in Fig. 3, illumination device 160 includes first light source 161 that emits light of a spectrum having a maximum peak in wavelength region (a) of 620 nm or more and second light source 162 that emits light of a spectrum having a maximum peak in wavelength region (b) of 580 nm or less. When the skin is irradiated with the light having the spectrum having the maximum peak in wavelength region (a) of 620 nm or more, a reflection characteristic of the skin becomes relatively high, and contrast with black hair can be emphasized. In addition, when the skin is irradiated with the light having the spectrum having the maximum peak within a wavelength region of wavelength region (b) of 580 nm or less, a reflection characteristic of the skin becomes relatively low, and contrast with white hair can be emphasized. In particular, when the skin is irradiated with light having a spectrum having a maximum peak in a wavelength region of 540 nm to 580 nm, since a relative reflection characteristic of melanin, hemoglobin, and the like decreases, the light having such a wavelength region is preferable.
Both first light source 161 and second light source 162 irradiate the entire region imaged by imaging device 131. First light source 161 and second light source 162 are attached to substrate 133 to which imaging device 131 is attached.
Notification device 140 is a device that notifies the user of a processing result of image processing device 150. The notification method of notification device 140 is not particularly limited, and examples thereof include a method for performing notification by sound (including voice), light, vibration, electrical stimulus, a combination thereof, or the like. In the case of the present exemplary embodiment, notification device 140 is a device that performs notification of information by light, and includes a plurality of light emitting elements such as LEDs arranged on a peripheral edge of an end of grip 110 close to head part 120. Notification device 140 can change at least one of brightness, color, and a light emission pattern of light.
Fig. 4 is a block diagram illustrating functional units of image processing device 150. Image processing device 150 is a device that controls illumination device 160 and imaging device 131 to process an image obtained from imaging device 131, and includes, as processing units implemented by a processor executing a program, imaging control unit 157 and property information generation unit 151. In the present exemplary embodiment, image processing device 150 further includes shaving information generation unit 152, result notification unit 153, and information acquisition unit 154.
Imaging control unit 157 controls illumination device 160 to individually emit light rays of different spectra, and controls imaging device 131 such that an imaging timing of imaging device 131 is synchronized with a timing at which illumination device 160 is caused to individually emit light rays. In the case of the present exemplary embodiment, imaging control unit 157 controls illumination device 160 such that first light source 161 and second light source 162 alternately emit light rays, and controls imaging device 131 such that imaging is executed in accordance with a timing at which each of first light source 161 and second light source 162 emits light.
Property information generation unit 151 processes the image imaged by imaging device 131 with the light rays of the different spectra emitted to a predetermined region, and generates property information indicating a property of a hair. The property information is, for example, information including at least one of a length of a hair, a direction in which a hair is grown, and a density of a hair.
An example of a case where property information generation unit 151 generates the property information indicating the length of the hair will be described. Property information generation unit 151 performs processing of enhancing contrast on each of images based on light rays of a plurality of different spectra acquired by information acquisition unit 154. For example, property information generation unit 151 increases luminance contrast by performing, on luminance of each pixel of the image, gradation conversion for increasing a change in output gradation with respect to input gradation. Note that fine noise such as irregularities of the skin may be removed by applying a lowpass filter to the image before or after the contrast enhancement.
Subsequently, property information generation unit 151 performs contour extraction on the image in which the contrast is enhanced. More specifically, property information generation unit 151 removes fine noise by binarizing (that is, whitening/blackening) such that a white pixel is output in a case where a luminance difference with a peripheral pixel is more than or equal to a threshold and a black pixel is output in a case where the luminance difference is less than the threshold and then performs expansion and contraction processing. Note that the expansion and contraction processing refers to expansion processing of replacing a pixel of interest with white in a case where at least one white pixel is present around the pixel of interest, and contraction processing of replacing a pixel of interest with black in a case where at least one black pixel is present around the pixel of interest. By using this contour extraction, an image showing contours of individual hairs is obtained.
Here, property information generation unit 151 may extract contours of hairs from a plurality of images of the identical region imaged based on the light rays emitted in the different spectra, and may integrate the contours in the plurality of images. Accordingly, it is possible to effectively generate the property information of the hair even in a case where the black hair and the white hair are mixed, such as in a case where the black hair and the white hair are grown at substantially the same ratio. In addition, property information generation unit 151 may compare the plurality of images of the same region imaged based on the light rays emitted in the different spectra, and may select one image according to a predetermined condition such as an image having a largest number of extracted contours. Accordingly, it is possible to accurately acquire the property information indicating the property of the hair for a hair having a color more frequently grown out of the black and white hairs.
Subsequently, property information generation unit 151 calculates a circumscribed rectangle for each region from which the contour is extracted. Specifically, property information generation unit 151 calculates the circumscribed rectangle for each region from which the contour is extracted such that the rectangular contour comes into contact with the region corresponding to the extracted hair. That is, a circumscribed rectangle surrounding a black portion is calculated for the black hair, and a circumscribed rectangle surrounding a white portion is calculated for the white hair. However, the calculation method of the circumscribed rectangle is not limited to this method, and any other method may be used as long as a rectangle covering the contour of the hair can be calculated in order to estimate a length of the hair. By the above processing, an image showing rectangles circumscribing the regions corresponding to the individual hairs is obtained.
Subsequently, property information generation unit 151 specifies the length of each hair by calculating a length of a long side of the circumscribed rectangle for each calculated circumscribed rectangle. For the specification of the length of the long side, the long side is set as an oblique side, lengths of two orthogonal sides in a right triangle including two sides along an orthogonal direction in which the pixels are arranged (here, a length of one side is given by the number of pixels × pixel interval) are calculated, and the length of the long side that is the oblique side is calculated by using the theorem of three squares. In addition, the direction of the hair may be calculated as the property information from the lengths of two orthogonal sides.

(Length and direction of hair)

By doing this, the lengths and directions of the individual hairs are specified from the image imaged by imaging device 131. Further, property information generation unit 151 performs statistical processing on the lengths and directions of the plurality of hairs included in the image, and generates information representing the lengths and directions of the plurality of hair in the image as numerically expressed property information. In the statistical processing, the length of the hair may be used as a weight, or only data of the length of the hair more than or equal to a predetermined length threshold may be used.

(Density of hair)

An example of a case where property information generation unit 151 generates the property information indicating the density of the hair will be described. The description is similar to the above description until property information generation unit 151 generates the image showing the contours of the individual hairs.
Subsequently, property information generation unit 151 calculates an area of each region from which the contour is extracted, and calculates a total area of each region in the image. Further, property information generation unit 151 generates a ratio of a total area of the rectangular region to an area of the image as numerically expressed property information indicating the density of the hair.
Shaving information generation unit 152 generates shaving information on shaving based on the property information generated by property information generation unit 151. The shaving information is information including at least one of a shaving direction and the end of shaving. For example, in a case where the property information indicating the hair length is less than or equal to a length threshold, shaving information generation unit 152 may generate shaving information indicating the end of shaving. In addition, in a case where the property information indicating the shaving density is less than or equal to a shaving density threshold, shaving information generation unit 152 may generate the shaving information indicating the end of shaving. In addition, shaving information generation unit 152 may generate shaving information indicating a shaving direction which is a direction in which shaving unit 121 is moved with respect to the skin.
In the case of the present exemplary embodiment, shaving information generation unit 152 may calculate a motion vector focusing on hair, skin texture, and the like from images imaged at predetermined intervals in the identical spectrum of light, and may generate shaving information of an excessive speed in a case where a speed obtained from the motion vector is more than or equal to a speed threshold. In addition, shaving information generation unit 152 may calculate a blur width of hair, skin texture, or the like from one image imaged at a predetermined shutter speed (that is, exposure time), and may generate the shaving information of the excessive speed in a case where the speed obtained from the shutter speed and the blur width is more than or equal to a speed threshold.
In addition, shaving information generation unit 152 may retain a plurality of thresholds having different values, such as a first length threshold that is 20% longer than the length threshold and a second length threshold that is 40% longer than the length threshold, and may generate shaving information that increases or decreases stepwise, such as shaving information corresponding to the level of the length of the hair.
After the property information becomes less than or equal to the length threshold and less than or equal to the shaving density threshold and the shaving information indicating the end of shaving is generated, in a case where the shaving information indicating the end of shaving is further generated from newly generated property information, shaving information generation unit 152 may generate shaving information indicating excessive shaving.
Result notification unit 153 controls notification device 140 to notify the user of the shaving information generated by shaving information generation unit 152. For example, result notification unit 153 notifies the user of the shaving information by controlling light emitted from a light emitting device included in notification device 140 to change at least one of the brightness, the color, and the light emission pattern. At a stage when the length of the hair is long, control is performed such that red light is emitted to notify the user of the non-end of shaving, and when the shaving information indicating the end of shaving is acquired from shaving information generation unit 152, control is performed such that blue light is emitted to notify the user of the end of shaving. Further, in a case where the user performs a shaving operation on a region where a hair having a length less than or equal to a length threshold is present, notification device 140 may be controlled to blink in red, and thus, the excessive shaving may be notified.
In addition, in a case where shaving information generation unit 152 generates the shaving information that increases or decreases stepwise, result notification unit 153 may notify the user of the stepwise shaving information by controlling the light emitted from the light emitting device to change at least one of the brightness, the color, and the light emission pattern stepwise. For example, the intensity of the light may be increased or decreased stepwise, or a blinking interval of the light may be increased or decreased.
According to electric razor 100 of the above exemplary embodiment, information on the hair is extracted from each image imaged by imaging device 131 based on the light rays of the plurality of spectra regardless of the color of the hair, and the shaving information on the shaving can be notified to the user. Accordingly, the user can execute shaving processing while the user recognizes a speed at which electric razor 100 moves relative to the skin, the end of shaving in a predetermined region, and the like, and can efficiently perform a shaving operation regardless of the color of the hair while damage to the skin is suppressed.
Note that the present disclosure is not limited to the above exemplary embodiments. For example, another exemplary embodiment implemented by optionally combining the components described in the present description or by excluding some of the components may be an exemplary embodiment of the present disclosure. In addition, the present disclosure also includes variations obtained by making various modifications conceivable by those skilled in the art without departing from the spirit of the present disclosure, in other words, without departing from the meaning indicated by the wording described in the claims.
For example, in the above exemplary embodiment, although a case where the skin is irradiated with the light rays of the different spectra being sequentially switched has been described, as illustrated in Fig. 5, in image processing device 150, information acquisition unit 154 may acquire input information input by the user using input button 112, and imaging control unit 157 may control illumination device 160 and imaging device 131 such that imaging is performed by being irradiated only with light of a spectrum corresponding to the input information. As a result, it is possible to change a mode while the user recognizes that the user shaves black hair, shaves white hair, or the like, and it is possible to execute shaving. Accordingly, a speed of image processing can be increased.
In addition, property information generation unit 151 may extract an image having a wavelength in a specific region from the acquired image and may generate the property information based on the extracted image. According to this, there is a possibility that the contrast between the hair and the skin can be further enhanced.
In addition, although notification device 140 including the light emitting element has been exemplified, notification device 140 may include a sound producing device such as a speaker, a vibration device that generates vibration in grip 110, an electrical muscle stimulation device that applies electrical stimulus to the hand gripping grip 110, and the like. Such notification device 140 can perform the notification of the shaving information by changing sound (including voice), vibration, intensity of electrical stimulus, a generation pattern, a direction, and the like.
In addition, in the above exemplary embodiments, although shaving unit 121 that includes a total of five outer blades including four first outer blades 122 and one second outer blade 123 has been exemplified, the number of outer blades is not particularly limited, and shaving unit 121 may include four or less outer blades or six or more outer blades.
In addition, shaving unit 121 may be configured to shave hair by rotating the inner blade with respect to the outer blades.
In addition, the attachment position of imaging device 131 is not limited to the above exemplary embodiments, and may be attached to, for example, a rear side (X+ side in the drawing), a side (Y- side and Y+ side in the drawing), or the like. In addition, the first imaging device may be attached to grip 110. The number of imaging devices 131 is not limited to one, and may be attached to a plurality of places.

INDUSTRIAL APPLICABILITY

The present disclosure can be applied to electric razors capable of shaving hairs of animals including humans, such as so-called electric shavers for shaving beards and so-called hair clippers for shaving hairs.
Technical ideas derived from the present disclosure will be described below.
An electric razor derived from the present disclosure is an electric razor that includes a grip to be gripped by a user, and a head part having a shaving unit for cutting a hair, the head part being connected to an end of the grip.
The electric razor includes:

an imaging device that images a part near a skin with which the shaving unit comes into contact;
an illumination device that is configured to irradiate a region imaged by the imaging device with light rays of different spectra; and
an image processing device that processes an image acquired from the imaging device.

The image processing device includes:

an imaging control unit that controls the illumination device and the imaging device to cause the region to be imaged by being individually irradiated with the light rays of the different spectra; and
a property information generation unit that generates property information indicating a property of the hair based on the image imaged by the imaging device.

In other words, an electric razor derived from the present disclosure is an electric razor that includes a grip to be gripped by a user, and a head part having a shaving unit for cutting a hair, the head part being connected to an end of the grip.
The electric razor includes:

an imaging device that images a part near a skin with which the shaving unit comes into contact;
an illumination device that is configured to irradiate a region imaged by the imaging device with light rays of different spectra; and
electrical circuitry which processes an image obtained from the imaging device.

In operation, the electrical circuitry

controls the illumination device and the imaging device to cause the region to be imaged by being individually irradiated with the light rays of the different spectra; and
generates property information indicating a property of the hair based on the image imaged by the imaging device.

Examples of the electrical circuitry are semiconductor devices, such as an integrated circuit (commonly referred to as "IC") or a large scale integrated circuit (commonly referred to as "LSI").

REFERENCE MARKS IN THE DRAWINGS

100: electric razor
110: grip
111: power supply switch
112: input button
120: head part
121: shaving unit
122: first outer blade
123: second outer blade
124: head frame
125: head base body
131: imaging device
133: substrate
134: cover
140: notification device
150: image processing device
151: property information generation unit
152: shaving information generation unit
153: result notification unit
154: information acquisition unit
157: imaging control unit
160: illumination device
161: first light source
162: second light source

Claims

An electric razor that includes a grip to be gripped by a user, and a head part comprising a shaving unit for cutting a hair, the head part being connected to an end of the grip, the electric razor comprising:
an imaging device that images a part near a skin with which the shaving unit comes into contact;

an illumination device that is configured to irradiate a region imaged by the imaging device with light rays of different spectra; and

an image processing device that processes an image acquired from the imaging device,

wherein

the image processing device comprises:
an imaging control unit that controls the illumination device and the imaging device to cause the region to be imaged by being individually irradiated with the light rays of the different spectra; and

a property information generation unit that generates property information indicating a property of the hair based on the image imaged by the imaging device.
The electric razor according to Claim 1, wherein
the image processing device further comprises an information acquisition unit that acquires input information input by the user, and

the imaging control unit controls the illumination device and the imaging device to cause the region to be imaged by being irradiated with light of a spectrum corresponding to the input information.
The electric razor according to Claim 1 or 2, wherein
the illumination device is configured to irradiate the region with light of a spectrum having a maximum peak in a wavelength region of 620 nm or more and light of a spectrum having a maximum peak in a wavelength region of 580 nm or less.