Light source module for laser hair removal and laser hair removal instrument

Abstract

The embodiment of the utility model discloses a light source module for laser hair removal and a laser hair removal instrument, which are used for realizing the light source module with a good homogenization effect at lower cost on the premise of ensuring portability. The light source module for laser hair removal comprises a light source array comprising a plurality of light emitting units, and each light emitting unit is used for emitting a light beam; comprising a plurality of lens units, and each lens unit is used for performing diffusion processing on at least one corresponding light beam and guiding the light beam subjected to the diffusion processing to an optical waveguide; and the optical waveguide is used for carrying out homogenization treatment on the incident light beam subjected to the diffusion treatment.

Description

Technical Field

[0001] This application relates to the field of laser hair removal technology, and more particularly to a light source module and a laser hair removal device for laser hair removal. Background Technology

[0002] Hair removal devices in the medical aesthetics field are based on the principle of selective photothermolysis. They use light of a specific wavelength to penetrate the epidermis and target hair follicles rich in melanin, selectively heating and destroying the hair follicles and surrounding tissues in order to achieve permanent hair removal.

[0003] To ensure safety and effectiveness, the point-source laser light emitted by home-use hair removal devices does not directly irradiate the user's skin. Instead, it undergoes homogenization processing to transform it into a laser with uniform energy distribution. This ensures that the energy received by different areas of the treated skin is similar, thus guaranteeing even hair removal results. Furthermore, considering the purchasing power of users, home-use hair removal devices cannot use high-cost homogenization components like those in commercial devices. Therefore, they typically employ more affordable homogenization components such as optical waveguides.

[0004] In practical applications, the homogenization capability of an optical waveguide is related to its thickness. To achieve higher uniformity of the emitted laser, the waveguide thickness must be increased, which reduces the portability of home-use hair removal devices. Therefore, there is an urgent need for a light source module that can achieve good homogenization at a lower cost while maintaining portability. Summary of the Invention

[0005] This application provides a light source module and a laser hair removal device for laser hair removal, which are used to achieve a good uniformity effect at a low cost while ensuring portability.

[0006] The first aspect of this application provides a light source module for laser hair removal, comprising:

[0007] A light source array comprising multiple light-emitting units, each of which is used to emit a beam of light;

[0008] A lens array comprising multiple lens units, each of the lens units being used to diffuse at least one corresponding beam and guide the diffused beam to an optical waveguide;

[0009] The optical waveguide is used to homogenize the incident light beam after the diffusion process and to emit uniform laser light.

[0010] In some specific implementations, the optical waveguide is a solid optical waveguide or a hollow optical waveguide.

[0011] In some specific implementations, the material of the solid optical waveguide includes BK7, quartz, or sapphire.

[0012] In some specific implementations, the core layer of the hollow optical waveguide is air or a low-refractive-index material.

[0013] In some specific implementations, the lens unit includes a negative lens or a spherical mirror.

[0014] In some specific implementations, each beam of light passes through the optical center of a uniquely corresponding lens unit, is diffused by the uniquely corresponding lens unit, and is guided by the lens unit to the optical waveguide.

[0015] In some specific implementations, the light beam emitted by the light-emitting unit is a pulsed laser or a continuous laser.

[0016] The second aspect of this application provides a laser hair removal device, comprising:

[0017] A light source module for laser hair removal as described in any of the first aspects, the light source module being used to emit uniform laser light that irradiates the skin.

[0018] A driving module is used to supply current to the light-emitting units in the light source module;

[0019] A control module is used to control the drive module to provide current to the light-emitting unit in the light source module.

[0020] In some specific implementations, one end of the lens unit is attached to one end of the optical waveguide to form a light-uniforming component, and the light-uniforming component and the light source array are respectively disposed in the laser hair removal device.

[0021] In some specific implementations, the laser hair removal device further includes:

[0022] The cooling module, controlled by the control module, is used to reduce the temperature of the area of ​​the light source module that comes into contact with the user's skin.

[0023] As can be seen from the above technical solutions, the embodiments of this application have the following advantages: This application, through analysis of existing technologies for beam homogenization using optical waveguides, discovers a correlation between the number of reflections of light in the optical waveguide and the homogenization effect of the optical waveguide. That is, the more times light is reflected in the optical waveguide, the more uniform the beam emitted from the optical waveguide. Subsequently, the inventors of this application realized that the interior of an optical waveguide is equivalent to parallel reflecting mirrors. Between two mirrors at a certain distance, the exit direction of the beam after each of the two reflections is the same as the incident direction of the beam's initial reflection. The only way to increase the number of reflections is to increase the incident angle of the light, that is, to reduce the optical path length of each reflection to allow the beam to reflect more times over a finite distance. Therefore, this application introduces a lens array including multiple lens units to expand the beam of light emitted by the light-emitting unit, thereby increasing the incident angle of light onto the optical waveguide, increasing the number of reflections of light in the optical waveguide, and thus achieving more uniform laser emission from the optical waveguide. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0025] Figure 1 This is a schematic diagram of the structure of a light source module for laser hair removal according to an embodiment of this application;

[0026] Figure 2 This is a schematic diagram illustrating the effect of the optical waveguide reflection principle in an embodiment of this application;

[0027] Figure 3 This is another schematic diagram illustrating the effect of the optical waveguide reflection principle in the embodiments of this application;

[0028] Figure 4 This is a schematic diagram illustrating the effect of prior art homogenization processing in an embodiment of this application;

[0029] Figure 5 This is a schematic diagram illustrating the effect of homogenization processing in an embodiment of this application. Detailed Implementation

[0030] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0031] In the description of the embodiments of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0033] In addition to the problems of the prior art pointed out in the background section, the insufficient uniformity of the light source module in the prior art also leads to the following problems:

[0034] 1. Safety Issues: Uneven light source modules may increase the risk of skin damage during use. Some areas may receive excessive light energy, potentially causing burns or pigmentation, while other areas may not receive enough light energy for effective hair removal.

[0035] 2. Unsatisfactory results: Uneven light distribution in the light source module may prevent some hair follicles from receiving sufficient light, affecting the hair removal effect. This may require multiple uses or increased energy to achieve the desired hair removal effect, increasing both usage and time costs.

[0036] 3. Poor user experience: Uneven light source modules may cause discomfort to users. For example, some areas may feel heat or stinging, while other areas may not feel anything, affecting the overall user experience.

[0037] Therefore, in order to solve the problems caused by insufficient uniformity of the light source module, this application provides a light source module for laser hair removal and a laser hair removal device.

[0038] Please see Figure 1 One embodiment of the light source module for laser hair removal in this application includes:

[0039] A light source array comprising multiple light-emitting units, each of which emits a beam of light;

[0040] A lens array comprising multiple lens units, each lens unit being used to diffuse at least one corresponding beam and guide the diffused beam to an optical waveguide.

[0041] Optical waveguides are used to homogenize incident diffused light beams and enable uniform laser output.

[0042] To better illustrate the technical solutions of the embodiments of this application, the basic principle of homogenization processing of optical waveguides is briefly explained below. When light rays are reflected inside an optical waveguide, they diffuse and intersect in space. This multiple reflection makes the light path more complex, causing light rays with different incident angles and positions to intersect and mix. This mixing effect helps to make the originally non-uniform light field more uniform, because the phase and amplitude of the light rays influence and superimpose each other, ultimately forming a more uniform light field distribution. Based on the above, it can be seen that increasing the number of reflections of light rays in an optical waveguide is equivalent to promoting the mixing and diffusion of the light field through multiple reflections, thereby significantly improving the homogenization effect of the optical waveguide.

[0043] Similarly, it can be deduced that the reason why increasing the thickness or length of the optical waveguide can enhance the uniformity of the emitted beam is that the number of reflections of light in the optical waveguide increases.

[0044] Based on the above, embodiments of this application consider increasing the number of reflections of light within the optical waveguide through means other than increasing the waveguide thickness. It is understood that for a reflected ray, its angle of incidence and angle of reflection are constant. Based on their understanding of the aforementioned reflection principle, the inventors of this application have experimentally simulated and discovered that in a closed space of finite length, the greater the angle at which the incident ray first strikes the surface of the closed space, the more times the incident ray is reflected within that closed space.

[0045] Please refer to Figure 2 The internal surface of the optical waveguide is approximately a total reflection surface. Figure 2 The red dot 1 represents the first intersection point of a ray of light originating from the green dot, incident at a large angle (i.e., a relatively large incident angle) into the optical waveguide and onto its inner surface. The trajectory of this ray within the waveguide is shown below. Figure 2As shown by the dark green line, the light here is reflected up to 23 times inside the optical waveguide; Figure 2 Red dot 2 represents the first intersection point of a small-angle incident (i.e., small incident angle) light ray originating from the green dot with the inner surface of the optical waveguide. The trajectory of this light ray within the waveguide is shown below. Figure 2 As shown by the light green line, the light beam here is reflected only 3 times inside the optical waveguide. In summary, light incident at a large angle undergoes significantly more reflections within the optical waveguide. This means that increasing the angle at which the beam enters the waveguide increases the number of reflections per ray within the waveguide, thereby improving the uniformity of the output beam.

[0046] Furthermore, the inventors of this application noted that in existing technologies, the light beam emitted by the light-emitting unit can be directly incident on the optical waveguide without any processing. That is, the angle at which the light beam enters the optical waveguide is related to the beam's divergence angle. Therefore, the inventors of this application considered increasing the angle at which the light beam enters the optical waveguide by widening the divergence angle of the beam incident on it, thereby increasing the number of reflections of each ray within the waveguide. This improves the uniformity of the emitted beam, as detailed below.

[0047] First, based on the principle of hair removal devices mentioned in the background technology, it's clear that only lasers of sufficient intensity can penetrate the epidermis and cause substantial damage to the hair follicle. However, the low-cost light-emitting units in existing home hair removal devices cannot individually provide enough laser energy to destroy the hair follicle and surrounding tissue. Therefore, in practical applications, a light source array containing multiple light-emitting units can be used to provide sufficient laser energy to achieve the desired hair removal effect. The arrangement of the light-emitting units in the array can be configured as needed, and each unit emits an independent beam of light.

[0048] Subsequently, before homogenizing the light beam, this application introduces a lens array comprising multiple lens units to diffuse (or diverge or beam expand) the light beam emitted by each light-emitting unit, thereby increasing the divergence angle of the light beam emitted by each light-emitting unit. The reasons for increasing the beam divergence angle are explained in the aforementioned related content and will not be repeated here. Specifically, Figure 3 The upper middle figure shows the reflection of the light beam inside the optical waveguide after it enters without diffusion (without a lens). The lower figure shows the reflection of the light beam inside the optical waveguide after it enters with diffusion (through a lens). It is clear that adding a lens unit significantly increases the number of reflections of the light beam inside the optical waveguide, and the emitted light beam is significantly more uniform.

[0049] Finally, the diffused light beam is incident into the optical waveguide, where it homogenizes each beam to ensure better uniformity of the beam exiting the waveguide compared to the incident beam, thus achieving better hair removal results. The diffused light beam has a larger divergence angle than the beam emitted by the light-emitting unit. Therefore, compared to existing technologies that directly guide the beam emitted by the light-emitting unit into the optical waveguide, this embodiment guides the diffused light beam into the optical waveguide, resulting in significantly better uniformity of the beam exiting the waveguide.

[0050] Next, in order to better demonstrate the technical effect of the technical solution of this application, the following will be combined with Figure 4 , 5 The homogenization effect of the light source module for laser hair removal provided in this application is explained.

[0051] first, Figure 4 This describes the homogenization effect of emitted light from optical waveguides at different thicknesses in existing technical solutions. Figure 4 The three figures, from top to bottom, show the energy distribution of the optical waveguide's output surface at thicknesses of 30m, 35mm, and 40mm (corresponding to light rod heights of 30mm, 35mm, and 40mm, respectively). The table to the right of each figure records the maximum and minimum irradiance, as well as the irradiance uniformity, of the output surface. The irradiance uniformity shown in the figures refers to the uniformity of the irradiance on the output surface. Figure 4 As shown in the figures, as the thickness of the optical waveguide increases, the irradiance uniformity also gradually increases from 55.06% to 63.73% and 84.94%.

[0052] In this embodiment, by adding a lens array, the optical waveguide thickness is only 18mm, achieving the desired effect. Figure 5 The homogenization effect shown is as follows: the uniformity of the emitted light reaches 91.52%. Furthermore, the thickness of the lens array plus the optical waveguide in this embodiment is only 20mm, yet the homogenization effect is significantly better than... Figure 4 Given the existing technology that can achieve uniformity in optical waveguides with a thickness of 40mm, the embodiments of this application provide a light source module with good uniformity at a lower cost while ensuring portability.

[0053] In some specific implementations, the optical waveguide in this application embodiment can be a solid optical waveguide or a hollow optical waveguide, which can be configured as needed. It should be noted that, regardless of whether a solid or hollow optical waveguide is used, the optical waveguide material in this application embodiment should be a material that has good total internal reflection effect on the wavelength band of the processed beam and low absorption rate on the wavelength band of the processed beam, such as BK7, quartz, sapphire, etc. In particular, the angle at which the light enters the optical waveguide should be smaller than the total internal reflection angle of the optical waveguide to ensure that the beam can undergo total internal reflection within the optical waveguide. In addition, in practical applications, the core layer of a solid optical waveguide can be a glass material such as BK7, quartz, sapphire, etc., while the core layer of a hollow optical waveguide can be air or a low refractive index material, etc., and the outer periphery of the optical waveguide in this application embodiment is coated with a reflective film, such as a metal reflective film or a dielectric reflective film, etc.

[0054] In some specific embodiments, the lens unit of this application can be any optical device, such as a concave lens or a spherical mirror, that can make the outgoing light divergence angle greater than the incident light divergence angle, or any optical device that can diffuse the light beam incident thereon.

[0055] Based on the foregoing embodiments, in practical applications, the optical center of each lens unit in this application typically has the best diffusion effect. In other words, if each beam passes through the optical center of a uniquely corresponding lens unit and is diffused by that uniquely corresponding lens unit, then each beam fully utilizes the diffusion capability of the corresponding lens unit, achieving beam divergence.

[0056] The foregoing has described various embodiments of the light source module for laser hair removal. In practical applications, the light source module for laser hair removal can be used as part of a laser hair removal device to provide a better hair removal experience.

[0057] In one specific implementation, the laser hair removal device of this application includes: a light source module for laser hair removal as described in any of the foregoing embodiments, which is used to emit uniform laser light to irradiate the skin; a driving module for providing current to the light-emitting unit in the light source module; and a control module for controlling the driving module to provide current to the light-emitting unit in the light source module.

[0058] Specifically, since the light-emitting units in the light source module are generally laser chips, a drive module is also needed in the laser hair removal device as an energy source to provide current to each light-emitting unit in the light source module. Furthermore, because the laser chip works by injecting current to excite laser emission, the magnitude of the current directly affects the recombination rate of electrons and holes in the laser chip, thus affecting the light emission intensity. Therefore, the control module can control the magnitude of the current provided by the drive module to the light-emitting units, thereby controlling the light emission intensity of the light-emitting units.

[0059] In another implementation, this application also provides a laser hair removal device, similar to the aforementioned embodiments, except that it further includes a cooling module controlled by a control module, used to reduce the temperature of the area in the light source module that comes into contact with the user's skin.

[0060] It is understandable that in order to damage hair follicles deep within the skin, the light source module must provide a uniform laser with high luminous intensity. Therefore, to provide this uniform laser, the light source module generates a significant amount of heat during operation. Excessive heat during contact between the laser hair removal device and the user's skin can potentially damage the skin. To avoid this problem, this application embodiment additionally provides a cooling module. This cooling module, under the control of the control module, reduces the temperature of the portion of the laser hair removal device that directly contacts the user's skin, i.e., reduces the temperature of the area of ​​the light source module in contact with the user's skin, thereby preventing harm to the user.

[0061] It should be noted that the uniform laser spot emitted by the light source module in this embodiment is not limited to the rectangle shown in the accompanying drawings. In fact, the shape of the uniform laser spot emitted by the light source module mainly depends on the shape of the optical waveguide cross-section. Therefore, the uniform laser spot emitted by the light source module can also be any shape that meets the requirements, such as a circle or a polygon. Specifically, it can be achieved by adjusting the shape of the optical waveguide cross-section, which is not limited in this application.

[0062] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them.

Claims

1. A light source module for laser hair removal, characterized in that, include: A light source array comprising multiple light-emitting units, each of which is used to emit a beam of light; A lens array comprising multiple lens units is disposed between the light source array and the optical waveguide. Each lens unit is used to diffuse at least one corresponding beam to expand the divergence angle of the beam and guide the diffused beam to be incident on the optical waveguide. The optical waveguide is used to homogenize the incident light beam after the diffusion process and to emit uniform laser light.

2. The light source module for laser hair removal according to claim 1, characterized in that, The optical waveguide is either a solid optical waveguide or a hollow optical waveguide.

3. The light source module for laser hair removal according to claim 2, characterized in that, The solid-core optical waveguide is made of materials including BK7, quartz, or sapphire.

4. The light source module for laser hair removal according to claim 2, characterized in that, The core layer of the hollow optical waveguide is air or a low-refractive-index material.

5. The light source module for laser hair removal according to claim 1, characterized in that, The lens unit includes a negative lens or a spherical mirror.

6. The light source module for laser hair removal according to claim 1, characterized in that, Each beam of light passes through the optical center of a uniquely corresponding lens unit, is diffused by the uniquely corresponding lens unit, and is guided by the lens unit to the optical waveguide.

7. The light source module for laser hair removal according to claim 1, characterized in that, The light beam emitted by the light-emitting unit is a pulsed laser or a continuous laser.

8. A laser hair removal device, characterized in that, include: The light source module for laser hair removal as described in any one of claims 1 to 7, wherein the light source module is used to emit uniform laser light that irradiates the skin; A driving module is used to supply current to the light-emitting units in the light source module; A control module is used to control the drive module to provide current to the light-emitting unit in the light source module.

9. The laser hair removal device according to claim 8, characterized in that, One end of the lens unit is attached to one end of the optical waveguide to form a light-uniforming component, and the light-uniforming component and the light source array are respectively disposed in the laser hair removal device.

10. The laser hair removal device according to claim 8, characterized in that, The laser hair removal device also includes: The cooling module, controlled by the control module, is used to reduce the temperature of the area of ​​the light source module that comes into contact with the user's skin.

Images