JP2763823B2 - Method and apparatus for measuring thickness of stratum corneum - Google Patents

Description

The present invention relates to a method for measuring the thickness of a stratum corneum (hereinafter referred to as a stratum corneum) of a human body and an apparatus for measuring the thickness, and more particularly, to any treatment for the skin of a human body. The present invention relates to a method and apparatus for measuring the thickness of the stratum corneum, which can accurately measure the thickness of the stratum corneum without applying the method.

[Conventional technology]

Measuring the thickness of the stratum corneum of the human skin is important for knowing the properties of the skin and the degree of aging.

Conventionally, as a method for measuring the thickness of the stratum corneum, a method is known in which the skin is excised and the excised skin is observed with a microscope to measure. There is also known a method of estimating the thickness of each layer by applying ultrasonic waves to the skin.

[Problems to be solved by the invention]

However, among the above-described methods for measuring the thickness of the stratum corneum, the former method has a drawback that it is difficult to apply the method to skin other than the affected skin. In addition, there is a possibility that the excised skin dries before the measurement, and the thickness of the stratum corneum changes. Furthermore, the excised skin is fixed on a sample stage for microscopic observation. Depending on the fixing method, there is a possibility that the measured value of the thickness of the stratum corneum may change.

Also, the latter method using ultrasonic waves has low resolution,
There was a disadvantage that the accuracy was not sufficient.

Therefore, the object of the present invention is not limited to the affected skin,
An object of the present invention is to provide a method and apparatus for measuring the thickness of a stratum corneum that can be applied to any skin without causing inflammation or pain and that can accurately measure the thickness of the stratum corneum.

[Means for solving the problem]

The present inventors have conducted intensive studies to achieve the above object,
When the skin was irradiated with a laser beam having a wavelength of 632.8 nm and the intensity distribution of the reflected light reflected from the stratum corneum of the skin was determined, it was found that the thickness of the stratum corneum could be accurately measured.

The present invention has been made based on the above findings, and irradiates the skin with laser light having a wavelength of 632.8 nm by laser light irradiation means, and reflects the skin from the horny layer of the skin by detection means having a plurality of photoelectric conversion elements. The intensity of the reflected light of the laser light is detected, and the intensity distribution of the reflected light is obtained by signal processing means based on the detection signal from the detection means, and processed into thickness data of the stratum corneum. And measuring the thickness of the stratum corneum by measuring the thickness of the stratum corneum.

Further, the present invention, as a device suitable for carrying out the above method, a laser light irradiation means for irradiating the skin with a laser light having a wavelength of 623.8 nm, and the intensity of the reflected light of the laser light emitted from the laser light irradiation means A detection unit comprising a plurality of photoelectric conversion elements for detecting, and a signal processing unit for obtaining an intensity distribution of reflected light based on a detection signal from the detection unit and processing the intensity distribution of the stratum corneum to thickness data. And a stratum corneum thickness measuring device.

[Action]

According to the method and apparatus for measuring the thickness of the stratum corneum of the present invention, while irradiating the skin with laser light having a wavelength of 632.8 nm by laser light irradiation means, the detection means detects the intensity of the reflected light of the laser light, The intensity distribution of the reflected light is obtained by signal processing means and processed into thickness data of the stratum corneum, and the thickness of the stratum corneum is measured from the data. In addition, the present invention can be applied to measurement of the thickness of the stratum corneum of any skin, and can accurately measure the thickness of the stratum corneum.

〔Example〕

 Hereinafter, embodiments of the present invention will be described.

First, an embodiment of a stratum corneum thickness measuring apparatus according to the present invention will be described with reference to the drawings.

1 to 4 show one embodiment of the present invention. FIG. 1 is a schematic explanatory view of the entire stratum corneum analyzing apparatus including a stratum corneum thickness measuring apparatus according to the present embodiment. Is an explanatory diagram for explaining the principle of measuring reflected light, FIG. 3 is a graph showing the relationship between the position of the photodiode array and the intensity of the reflected light, and FIG. 4 is a graph showing the elasticity of the stratum corneum.

As shown in FIG. 1, a stratum corneum analyzing apparatus including a stratum corneum thickness measuring apparatus according to the present embodiment includes a semiconductor laser 1 as a laser beam irradiating means, and a photodiode array 2 as a detecting means. , A signal amplifier 3, a computer 4 as a signal processing means, a sound wave generator 5, and a photodiode 6. The semiconductor laser 1 is used to convert a human body into a stratum corneum SC (about 20 μm). Has thickness)
Is irradiated with laser light, the intensity of the reflected light of the laser light is detected by the photodiode array 2, the detection signal is amplified by the signal amplifier 3, and the analog-to-digital converter (A / D
After digitization by the D converter 7, signal processing is performed by the computer 4 to measure the thickness of each layer SC. Further, the stratum corneum analyzer irradiates a laser beam from the semiconductor laser 1 to the stratum corneum SC while applying vibration to the stratum corneum SC from the sound wave generator 5 and the photodiode 6.
Detects the change over time of the intensity of the reflected light from the stratum corneum SC of the human body, amplifies this detection signal by the signal amplifier 3, and
After digitizing with a digital converter (A / D converter) 7,
The signal processing is performed by the computer 4 to measure the elasticity of the stratum corneum SC.

The semiconductor laser 1 emits a laser beam at a wavelength of 632.8 nm, an output of 10 mW to 30 mW, and irradiates a predetermined portion of the skin with a laser beam through a green lens (focus lens) 1a, and has a lower end opened. It is arranged in the case 11. The incident angle of the laser beam emitted from the semiconductor laser 1 to the stratum corneum SC is preferably set to 177 ° to 130 °.

The photodiode array 2 includes a plurality of photodiodes as photoelectric conversion elements.
It detects the intensity of the reflected light from each of the approximately 20 or more stratum corneum SCs. That is, the photodiode array 2 is the second of the photodiodes that constitute it.
The photodiode at position A in the figure detects the intensity of light reflected from the uppermost stratum corneum, and the photodiode at position B in the same figure detects the intensity of light reflected from the lowermost stratum corneum. It is made to do. The photodiode array 2 is arranged in the case 11 similarly to the semiconductor laser 1. The photodiode array 2 includes:
It is preferable to arrange in a posture where the amount of incident light of reflected light from each stratum corneum SC is the largest, that is, a posture in which the optical axis is inclined by 3 ° to 50 ° with respect to the stratum corneum SC.

The input side of the signal amplifier 3 is connected to the computer 4
A switch 8 for switching between the photodiode array 2 and the photodiode 6 is disposed.

The computer 4 processes detection signals from the photodiode array 2 and the photodiode 6, and also controls the entire apparatus such as the semiconductor laser 1 and the photodiode 2, and a CPU for controlling the CPU. A ROM that stores a program and the like, and a RAM that temporarily stores detection signals from the photodiode array 2 and the photodiode 6, and the like. The relationship between the position of each photodiode of the photodiode array 2 and the output (intensity of reflected light) of each photodiode is analyzed and processed into thickness data of the stratum corneum SC. The relationship between the output of the photodiode 6 (the intensity of the reflected light) and the time change is analyzed, processed into elastic data of the stratum corneum SC, and this data is converted into a digital / analog converter (D / A). CRT through the exchanger) 9,
The data is output to a display device 10 such as an XY recorder.

The sound wave generator 5 is arranged in the case 11 so as to approach a laser light irradiation part of the semiconductor laser 1, and is configured to come into contact with a test part.

The photodiode 6 includes an objective lens 6a,
It detects the intensity of the reflected light from the surface of the horny layer SC, and is disposed in the case 11 so as to be located directly above the laser beam irradiation site of the semiconductor laser 1.

In the case 11, a prism 12 which is in contact with the surface of the stratum corneum SC which is a measurement site is disposed. This prism
Numeral 12 refracts the optical paths of the semiconductor laser 1, the photodiode array 2, and the photodiode 6 so that they can be arranged as close as possible to each other. That is, the case 11 is compact. It is to become.

Next, an embodiment of the method for measuring the thickness of the stratum corneum of the present invention using the above-described apparatus will be described.

First, the case 11 is set on the surface of the horny layer SC of a human body having a thickness of about 20 μm, and the computer 4 is operated to irradiate the semiconductor layer 1 with a laser beam having a wavelength of 632.8 nm from the semiconductor laser 1. The reflected light reflected from is converted into an electric signal by the photodiode array 2, the electric signal is amplified by the signal amplifier 3, digitized by the A / D converter 7, and then processed by the computer 4. The intensity distribution of the stratum corneum is processed into thickness data of the stratum corneum, and the stratum corneum SC is obtained from the data.
Obtain the total thickness (measure the thickness of the entire stratum corneum SC).

That is, when a laser beam having a wavelength of 632.8 nm is irradiated from the semiconductor laser 1 to the stratum corneum SC, the laser beam is incident on the inside of the stratum corneum SC, and a part of the laser light is reflected by the The light enters the diode array 2. At this time, as shown in FIG. 2, the photodiode at the position A of the photodiode array 2 is provided with the uppermost square layer SC.
The reflected light from the lowermost stratum corneum SC enters the photodiode at the position B in the same figure, and the reflected light from the lowermost stratum layer SC enters the photodiode at the position B in the same figure. The reflected light from the granular layer below the layer SC enters. The computer 4 analyzes the relationship between the position of each photodiode of the photodiode array 2 and the output (intensity of reflected light) of each photodiode, obtains the intensity distribution of the reflected light, and converts the intensity data into the thickness data of the stratum corneum. After processing, the thickness data of the stratum corneum is output to the display device 10 via the D / A converter 9. As a result, a graph as shown in FIG. 3 is displayed on the display device 10, and the thickness d of the entire stratum corneum SC can be measured from the graph.

When the stratum corneum SC is measured by irradiating a laser beam as described above, the present invention can be applied to measurement of the thickness of any stratum corneum, not limited to the affected stratum corneum.

In addition, there is no risk of damaging the skin, it is safe and does not involve inflammation or pain.

In addition, the thickness of the entire horny layer SC must be accurately measured because the thickness of the excised skin does not change due to drying and the fixing method of the excised skin does not change. Can be.

In addition, since the measurement time can be greatly reduced without any trouble, the measurement efficiency is improved as compared with the conventional measurement method.

When measuring the elasticity of the stratum corneum SC, the computer 4 operates the sound wave generator 5 to detect the intensity of the light reflected from the surface of the stratum corneum SC by the photodiode 6, and the detection signal of the photodiode 6 Is amplified by the signal amplifier 3, and A /
After being digitized by the D converter 7, the computer 4 changes the intensity of the reflected light with time, that is, the fourth change in the intensity of the reflected light.
The analysis is performed by analyzing the amplitude, phase shift, frequency dependence, and the like of the wave as shown in the figure.

In the above embodiment, the case where the thickness of the entire stratum corneum SC is measured is shown, but the thickness of one stratum corneum SC may be measured.

In the above embodiment, the case where the semiconductor laser 1 is used as the laser beam irradiation means has been described.
He-Ne laser that emits the above laser light may be used. In this case, the He-Ne laser may be disposed outside the case 11, and the laser light of the He-Ne laser may be guided to the focus lens 1a disposed inside the case 11 using an optical fiber. When the semiconductor laser 1 is used as the laser beam irradiating means as in the embodiment, the case 11
Can be compacted.

Further, the case where the photodiode array 2 is used as the detecting means has been described, but the present invention is not limited to this, and a plurality of photoelectric conversion elements such as phototransistors may be arranged.

〔The invention's effect〕

According to the method and apparatus for measuring the thickness of the stratum corneum of the present invention, it can be applied to any skin, without being limited to injured skin and without inflammation or pain, and can accurately measure the thickness of the stratum corneum. Can be measured.

[Brief description of the drawings]

1 to 4 show one embodiment of the present invention. FIG. 1 is a schematic explanatory view of the entire stratum corneum analyzing apparatus including a stratum corneum thickness measuring apparatus according to the present embodiment. Is an explanatory diagram for explaining the principle of measuring reflected light, FIG. 3 is a graph showing the relationship between the position of the photodiode array and the intensity of the reflected light, and FIG. 4 is a graph showing the elasticity of the stratum corneum. 1; laser beam irradiation means (semiconductor laser) 2; detection means (photodiode array) 4; signal processing means (computer) 10; display device

Claims (2)

(57) [Claims] (1) A laser beam irradiation means applies a wavelength of 632 to the skin.
While irradiating a laser beam of 8 nm, the detecting means having a plurality of photoelectric conversion elements detects the intensity of the reflected light of the laser light reflected from the stratum corneum of the skin, and the detection from the detecting means by the signal processing means. A method for measuring the thickness of a stratum corneum, comprising determining an intensity distribution of reflected light based on a signal, processing the data into thickness data of the stratum corneum, and measuring the thickness of the stratum corneum from the data. 2. A detecting means comprising: a laser light irradiating means for irradiating a skin with laser light having a wavelength of 632.8 nm; and a plurality of photoelectric conversion elements for detecting the intensity of reflected light of the laser light irradiated from said laser light irradiating means. And a signal processing means for obtaining the intensity distribution of the reflected light based on the detection signal from the detection means and processing it into thickness data of the stratum corneum.