KR101632383B1 - Skin imaging method and apparatus - Google Patents

Abstract

The present invention relates to a skin imaging method and a skin imaging apparatus, in which one white light source instead of R, G, and B light sources are used and the use of an RGB filter is avoided accordingly, so that a complicated rotation control of the RGB filter is unnecessary. An imaging according to a penetration depth with respect to a skin subject surface is realized by using a single white light source, a polarizer, and a Semrock filter. According to the present invention, unlike an existing skin imaging apparatus requiring a plurality of light sources and an RGB filter for irradiating a multi-wavelength, a low-cost skin imaging apparatus having a simple structure can be realized only with one white light source, a general polarizer, and a Semrock filter.

Description

[0001] The present invention relates to a skin imaging method and apparatus,

The present invention relates to a method and apparatus for performing skin imaging with a simple structure.

Skin imaging (imaging) techniques exist for the purpose of diagnosing or treating skin conditions or diseases (e.g., melanoma).

Figure 1 shows a schematic configuration of a conventional conventional skin imaging device.

G, and B light sources (2, 3, and 4) having different wavelengths are irradiated with red light, green light, and blue light, respectively, in order to image the skin condition depending on the depth of the object surface 1 (for example, And selectively irradiates the surface (1). The penetration depth of the light changes according to the wavelength of the irradiation light. In order to deeply view the image on the epidermis, it is necessary to irradiate light of a long wavelength band, thereby obtaining images reflected from the skin. The depth of penetration into the skin is generally in the order of R> G> B. When the light irradiated on the object surface 1 of the skin is reflected by the object surface 1, the reflected light passes through the RGB filter 5 and forms an image on the CCD 6. [ The RGB filter 5 is rotationally controlled by a motor.

In such a conventional skin imaging configuration, three light sources of R, G, and B are required, and an RGB filter is required, and a mechanism for rotating and controlling the RGB filter is required, so that the structure is complicated and the price is high.

Other prior arts include the following patent documents.

Patent Registration 10-0866552 (Published on November 3, 2008) Utility model registration 20-0291667 (Announcement date October 11, 2002)

By using a single white light source rather than the R, G, and B light sources, and thus avoiding the use of RGB filters, a skin imaging device and method that does not require complex RGB filter rotation control is conceived.

A single white light source is used, but a polarizer and a spherical filter are used to realize imaging according to the penetration depth of the skin surface.

A skin imaging apparatus according to a first aspect of the present invention includes a light source for emitting white light to a target surface of a skin to be imaged, a light source for emitting light from the light source, A wavelength variable portion for varying the wavelength band of the reflected light to emit the reflected light for each of a plurality of wavelength bands to obtain a separate image for each of at least one wavelength band along the wavelength band, And a processing unit for processing a signal output from the image processing unit.

In addition to the above-described configuration, a polarizer that polarizes incident white light vertically or horizontally to produce incident polarized light before the light emitted from the light source is irradiated onto the object surface of the skin to be imaged, A polarized light adjusting unit may be further included which is rotated to match the polarized component of the incident polarized light with the reflected light in the polarizer.

The light source is preferably a white LED or a xenon lamp.

The polarization controller is preferably a polarizing filter in which the vertical polarization and the horizontal polarization are changed by 90 °.

The wavelength tunable portion preferably includes a band pass filter and a filter rotator that rotates the band pass filter so that the band pass filter transmits light in a different wavelength band. In this case, the filter rotator may be constituted by a rotary shaft and a filter holder which is rotated by the rotary shaft and supports the filter. The filter holder is formed in a concave shape as a whole, A band-pass filter is inserted.

Preferably, the image forming unit includes a lens and a video device, and the processing unit is a DSP processor. Preferably, the video signal processed by the processing unit is connected to an external device (such as a computer or a smart phone) through communication means such as a USB port, and communication is performed between the processing unit and the external device. For this purpose, a predetermined application (application) may be installed in the external device.

According to a second aspect of the present invention, there is provided a skin imaging method comprising: irradiating a target surface of a skin to be imaged with white light; irradiating the surface of the skin with the light reflected by the skin to at least one wavelength band Varying the wavelength band of the reflected light so as to obtain a separate image, outputting the reflected light by a plurality of wavelength ranges, and image-processing the reflected light by the emitted plurality of wavelength ranges.

In the above method, in order to polarize incident white light selectively or vertically or horizontally before the white light is irradiated onto the surface of the skin, and to eliminate reflection noise on the surface of the skin surface, Component and the reflected light may be further included.

Here, it is preferable that the polarizing component of the incident polarized light is matched with the reflected light by a polarizing filter which is rotated 90 ° so that the vertical polarization and the horizontal polarization are changed.

Also, it is preferable to vary the wavelength band of the reflected light to emit the reflected light by a plurality of wavelength bands by using a band-pass filter, and the band-pass filter preferably transmits light of a different wavelength band by rotation.

The structure and operation of the present invention described above will become more apparent from the following detailed description of the invention together with the drawings.

According to the present invention, unlike a conventional skin imaging apparatus in which a plurality of light sources and RGB filters are required for irradiation of multiple wavelengths, only one white light source and a general polarizer and a plurality of spherical filters are required, so that a low cost skin imaging with a simple structure can be realized.

FIG. 1 is a block diagram for conceptual illustration of a conventional skin imaging method and apparatus.
2 is a schematic diagram of a skin imaging apparatus according to the present invention
Fig. 3 is a schematic view of a skin imaging apparatus according to an embodiment of the present invention.
Fig. 4 is a view showing the concept of the rotation of the filter variable portion
5 is a diagram showing a configuration of a filter rotation port for rotating and replacing the filter
6 is an illustration of a spectrum plot showing the transmission intensity of a wavelength-specific image obtained by rotating TBP01-550 / 15 at 0 °, 30 °, 45 °, and 60 °.

2 is a schematic diagram of an embodiment of a skin imaging device according to the present invention.

A white light source 20 for emitting white light WH,

A polarizer 25 for selectively polarizing the white light vertically or horizontally to form incident polarized light 21 before the white light WH emitted from the light source 20 is irradiated onto the object surface 10 of the skin to be imaged,

A light receiving window 30 for receiving incident polarized light 21 polarized through the polarizer 25 and irradiating the object surface 10 of the skin to receive reflected light 22 reflected from the skin surface 10,

Is rotated to match the polarized component of the incident polarized light 21 in the polarizer 25 with the reflected light 22 received through the light receiving window 30 in order to remove the reflected noise from the surface of the skin target surface 10 The polarization controller 40,

The wavelength band of the reflected light 22 emitted through the polarization controller 40 is varied to obtain a separate image for each of at least one wavelength band according to the depth of the skin 10, A wavelength tunable portion 50 for emitting a wavelength-

(60) for forming a plurality of reflected lights (22) according to a plurality of wavelength bands emitted from the wavelength variable portion (50)

And a processing unit 70 for processing a signal output from the imaging unit 60.

An example of the appearance of the skin imaging apparatus according to the present invention composed of the above components is shown in FIG. A power switch 110 is installed in the main body housing 100 and a light source 20 is positioned and a round incidence portion 130 is positioned beside the power source. When the light emitted from the light source 20 is reflected on the surface of the skin, the reflected light is incident on the incident portion 130 and is incident on the polarization controller 40, the wavelength tuning unit 50, The imaging unit 60 and the processing unit 70. The video signal is outputted through the communication terminal 120 (for example, USB or micro USB port). The output image signal can be displayed on a computer or a smart phone or interfaced.

In the exemplary configuration of FIG. 3, the incident portion 130 may be the light receiving window 30 or the polarization controller 40. For example, when the light receiving window 30 is not installed separately, or a polarizing filter is installed in the incident portion 130 of FIG. 3 together with the light receiving window 30, and the rounded edge portion of the light receiving window 130 is turned by hand, . If the polarization controller 40 is automatically rotated, the polarization controller 40 may be installed inside the housing 100 and the incident unit 130 may be configured as the light receiving window 30.

Referring back to FIG. 2, each component will be described in detail.

The light source 20 uses a light source emitting white light, and a white LED or a xenon lamp can be used. The white light WH emitted from the white light source 20 is irradiated not only to the surface (epithelium) of the skin surface 10 but also to the deep part (dermis) and is reflected at different wavelengths at different depths.

The polarizer 25 works together with the polarization controller 40 to provide a light source 20 as a preliminary action for eliminating noise such as light spread, light accumulation, and light blur when the light is reflected by the surface 10 to be irradiated on the skin 10 Is selectively polarized vertically or horizontally to pass therethrough as incident polarized light 21 to the object surface 10. If the polarizer 25 is provided to horizontally polarize the white light WH, the polarization controller 40 should be rotated and adjusted to match the reflected light 22 of the horizontally polarized incident polarized light 21.

The incident polarized light 21 having a plurality of wavelengths mixed therein and polarized in a specific direction (for example, horizontal polarization) is reflected by the skin surface 10 and the reflected light 22 is received through the light receiving window 30.

The polarization controller 40 is for passing light that is aligned with the vertically or horizontally polarized reflected light 22 and is implemented by a polarizing filter in which the vertical and horizontal polarizations are adjusted by rotation. It is an easily practicable technique for a person skilled in the art to install a polarizer so as to rotate 90 degrees about the rotation axis and to manually or automatically rotate the polarization filter. If the polarizer 25 is installed in the vertical polarization mode, the polarized light adjusting unit 40 should be rotated to adjust the vertically polarized incident polarized light to pass through the aligned polarized light. To rotate the polarization controller 40 manually, it is necessary to expose the polarization converter 40 to the outside of the housing in the form of a mechanism for rotating the polarization filter, for example, a knob or an actuator. This is the same as mentioned above with reference to Fig. In order to automatically rotate the polarization controller 40, the rotation of the polarization filter may be stopped at the moment when the light amount of the light emitted from the polarization filter is maximum while the polarization filter is rotated using a motor.

The wavelength tuning unit 50 selectively transmits the reflected light reflected by the skin surface 10 for each wavelength band in order to acquire a spectral image for each wavelength band of 490 to 620 nm, which is a general wavelength for the skin surface 10 . To achieve this, a rotating band pass filter (Semrock) was used. The wavelength band can be varied by rotating the digital filter 50 at predetermined intervals (i.e., 0 deg., 30 deg., 45 deg., 60 deg.) Using a step motor 51 shown in Fig. As a result, the wavelength of the light passing through the filter is varied, and an image is acquired for each desired wavelength band (see FIG. 6).

The rotation of the band-pass filter of the tunable section 50 can be implemented in various ways. For example, a button for each rotation angle can be provided and rotated by a button operation from the outside of the apparatus of the present invention. Alternatively, it is possible to automatically rotate 0 °, 30 °, 45 °, and 60 ° at regular time intervals (for example, 1 to 2 seconds) (automatic scanning). Alternatively, it may be operated through an application (application) such as a computer or smart phone connected through the communication terminal 120 (for example, USB or micro USB port) shown in FIG.

In the meantime, since a single filter covering a relatively wide band of 490 to 620 nm has not been developed in the state of the art of the present invention, the present invention can provide a filter having a wavelength band of 490 to 550 nm, for example, using a SAMPLOCK filter model TBP01-550 / And acquires an image of a wavelength band of 550 to 620 nm by using a specular filter model TBP01-620 / 14. In other words, by using two of the two models, which can cover two wavelength bands, the image can be obtained over a wide band of 490 ~ 620nm.

The configuration of the filter rotation mechanism for implementing the rotation operation and the filter replacement mechanism of the wavelength tunable part as described above is illustrated in FIG. The filter rotating shaft shown in Fig. 5 is composed of a rotating shaft 52 and a filter holder 53 which is rotated by the rotating shaft and supports the filter. The filter holder 53 has a concave shape as a whole, and is rotated by a rotating shaft 52 below the filter holder 53, and a filter (not shown) is inserted into the groove of the concave portion. It is possible to selectively insert and separate two or more different central wavelength filters (for example, a digital filter TBP01-550 / 15 or TBP01-620 / 14) in the groove of the holder 53 according to the required wavelength band .

Fig. 6 shows a spectrum plot showing the transmission intensities of the wavelength-dependent images obtained by rotating TBP01-550 / 15 at 0 °, 30 °, 45 ° and 60 °. It can be seen that transmitted light having a wavelength of about 550 nm can be obtained at 0 ° and transmitted light having a wavelength of about 490 nm can be obtained at 60 ° rotation.

Claims (12)

delete A light source for irradiating white light onto a target surface of the skin to be imaged,
A polarizer for generating incident polarized light by selectively polarizing the white light vertically or horizontally before the white light emitted from the light source is irradiated onto the object surface of the skin to be imaged,
A polarization controller which is rotated to match the polarization component of the incident polarized light with the reflected light in the polarizer in order to remove reflected noise from the reflected light reflected from the skin subject surface through the polarizer,
A wavelength variable unit for varying a wavelength band of the reflected light and emitting reflected light for a plurality of wavelength ranges to obtain a separate image for each of at least one wavelength band according to the depth of the skin surface from the reflected light transmitted through the polarization controller,
An imaging element for imaging the reflected light according to the variable wavelength band emitted from the wavelength variable portion,
And a processing unit for image-processing the signal output from the imaging unit. The apparatus of claim 2, wherein the light source is a white LED or a xenon lamp. 3. The skin imaging apparatus of claim 2, wherein the polarization controller includes a polarization filter whose vertical polarization and horizontal polarization operations are changed by 90 degrees. The skin imaging apparatus of claim 2, wherein the wavelength tuning unit includes a band pass filter and a filter rotator that rotates the band pass filter so that the band pass filter transmits light of a different wavelength band. The filter holder according to claim 5, wherein the filter rotating shaft is composed of a rotating shaft and a filter holder which is rotated by the rotating shaft and supports the filter. The filter holder has a generally concave shape and is rotated by a rotating shaft below the rotating shaft, And the band-pass filter is inserted into the groove. 3. The skin imaging device of claim 2, wherein the imaging section comprises a lens and an imaging device, and wherein the processing section comprises a DSP processor. The apparatus of claim 7, wherein the processing unit communicates with an external device via a communication terminal. delete A white light is irradiated to the object surface of the skin to be imaged,
Before the white light is irradiated onto the surface of the skin, the white light is selectively polarized vertically or horizontally to produce incident polarized light,
A polarization component of the incident polarized light is matched with the reflected light so as to remove reflection noise from the reflected light reflected by the skin surface of the skin,
A wavelength band of the matched reflected light is varied to obtain a separate image from the matched reflected light by at least one wavelength band according to the depth of the skin surface,
And imaging the reflected light for each of the plurality of emitted wavelength ranges to perform image processing. 11. The method of claim 10, wherein the polarizing component of the incident polarized light is matched with the reflected light by a polarizing filter whose vertical polarization and horizontal polarization are changed by 90 degrees. 11. The method of claim 10, wherein varying the wavelength band of the reflected light and outputting the reflected light by a plurality of wavelength bands is performed using a band pass filter, wherein the band pass filter is a filter that transmits light of a different wavelength band Way.

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