Patent Description:
Techniques for the removal of unwanted hairs include shaving, electrolysis, plucking, laser and light therapies (known as photoepilation) and injection of therapeutic anti-androgens. Light-based technologies are also used in other types of dermatological treatments, including hair growth reduction and treating acne. In this context, documents <CIT> and <CIT> are referred to.

Light-based hair treatments inhibit the growth of hair by exposing the skin to bright flashes or pulses of light, known as intense pulsed light (IPL). Through the use of an appropriate configuration of the light energy, i.e. in terms of wavelength, intensity and/or pulse duration (if the light is to be pulsed), selective heating of the hair root and subsequent temporary or permanent damage to the hair follicle can be achieved. The IPL may be generated by a high intensity light source such as a gas discharge lamp (e.g., a Xenon flash lamp). The light penetrates the skin and is absorbed, among other places, in the root of the hair by the pigment melanin. This causes an increase in the temperature of the root of the hair to rise and subsequently the temperature of the surrounding tissue. The generated heat damages the hair follicles, and the growth of the hair is inhibited if the temperature rise is sufficient. This process is known as photothermolysis. When the treatment is repeated in intervals of <NUM> to <NUM> weeks, a long-lasting hair reduction is achieved.

Light-based hair removal can be performed using commercially available 'home-use' devices (i.e. consumer devices that are suitable for use by non-specialists) such as the Philips Lumea device. Home-use devices typically use IPL technology at a relatively low fluence (e.g. <NUM>-<NUM> J/cm<NUM>) compared to professional devices that use fluences in excess of <NUM> J/cm<NUM>. For home-use IPL devices, the treatment area (the area treated by the IPL when the device is held in a single position during use) is typically <NUM>-<NUM><NUM>, and the pulse rate is typically <NUM>. With these devices, a whole-body treatment typically takes <NUM>-<NUM> minutes. Feedback from users of these types of devices shows that faster treatment is desired. The treatment speed is dependent on the size of treatment area and the pulse rate. However, for a given lamp, increasing the size of the treatment area results in a lower fluence (light energy per unit area), and thus weaker hair epilation effectiveness.

The total light output of a discharge lamp is proportional to its length. In home-use IPL devices, the size of the discharge lamp is restricted by the size constraints associated with these devices. Thus, in view of the difficulties with increasing the size of the treatment window, and the restriction on the size of the light source, many IPL device manufacturers are working to reduce treatment time by developing flash lamps that operate at higher pulse rates.

IPL can also be used for skin rejuvenation, in which intense light pulses are used to improve the appearance of skin. For example, skin rejuvenation can be used to reduce the visibility of dark spots, redness, wrinkles, scarring, veins and/or broken capillaries. Skin rejuvenation treatment requires higher fluence than hair removal treatment, and so, while there are IPL devices on the market that claim to provide both hair removal and skin rejuvenation, the effectiveness of the skin rejuvenation function is limited by the relatively low fluence provided by existing home-use IPL devices.

It is an object of the present disclosure to provide a treatment device that can perform both hair removal and skin rejuvenation effectively. Furthermore, it is desirable for the device to perform faster hair removal treatment than existing devices.

According to the disclosure herein, it is proposed to provide a dual-function treatment device that can operate in two modes: one for performing hair removal treatment and one for performing skin rejuvenation treatment. In particular, it is proposed that a U-shaped light source and a reflector of a treatment device have a first configuration for performing hair removal and a second configuration for performing skin rejuvenation.

According to an aspect, there is provided a treatment device for performing light-based treatment operations on or to a subject, wherein the treatment device comprises a U-shaped light source extending along a first axis for emitting a light pulse, a light exit window through which the light pulse is emitted from the treatment device, and a reflector for reflecting the light pulse towards the light exit window, wherein the treatment device is configured such that the light source and the reflector have a first operating configuration for performing hair removal on the subject, and the light source and the reflector have a second operating configuration for performing skin rejuvenation on the subject, and wherein the light source is rotatable about the first axis to switch between operating in the first configuration and the second configuration.

The use of a U-shape light source can provide a larger treatment area in the first configuration to provide faster hair removal treatment. The fluence level required for hair removal is maintained across this larger treatment area by the use of the U-shaped light source instead of a single straight light source. The compact design of a U-shaped light source can provide significantly higher energy output than a single straight light source without requiring much more space in the IPL device. Thus, the present disclosure provides a more efficient use of space within the device, where space is restricted.

The focusing of the light pulse from the light source into a smaller treatment area in the second configuration provides higher fluence than existing devices, and thus improves the effectiveness of the skin rejuvenation treatment.

Thus, dual functionality is provided with faster hair removal treatment. This is achieved without compromising the compact size of the device or the effectiveness of the skin rejuvenation treatment.

<FIG> is an illustration of an exemplary treatment device <NUM> that can be used to apply a light pulse to an area of skin. It will be appreciated that the treatment device <NUM> in <FIG> is merely presented as an example of a hand-held treatment device <NUM> that the invention can be used with, and the treatment device <NUM> is not limited to the form shown in <FIG> or to being a hand-held treatment device. The treatment device <NUM> is for use on a body of a subject (e.g. a person or an animal), and is to be held in one or both hands of a user during use. The treatment device <NUM> is to perform some treatment operations to hairs and/or skin of the body of the subject using one or more light pulses when the treatment device <NUM> is close to or in contact with a body part of the subject. The treatment operations include the removal of hairs by laser and/or light therapies (known as a photoepilation treatment or Intense Pulsed Light treatment). The treatment operations also include skin rejuvenation.

As described herein, the treatment device <NUM> is operated or used by a 'user', and the treatment device <NUM> is used on a body of a 'subject'. In some cases, the user and the subject is the same person, i.e. the treatment device <NUM> is held in a hand and used by a user on themselves (e.g. used on the skin on their leg). In other cases, the user and the subject are different people, e.g. the treatment device <NUM> is held in a hand and used by a user on someone else.

The exemplary treatment device <NUM> comprises a housing <NUM> that includes at least a handle portion <NUM> and a head portion <NUM>. The handle portion <NUM> is shaped to enable the user to hold the treatment device <NUM> with one hand. The head portion <NUM> is at a head end <NUM> of the housing <NUM>, and the head portion <NUM> is to be placed into contact with the subject in order for the personal care operation to be performed on the body or skin of the subject at the position that the head portion <NUM> is in contact with the body or skin.

The treatment device <NUM> is for performing a treatment operation using light pulses. Thus, in <FIG> the head portion <NUM> comprises an aperture <NUM>, also referred to as a light exit window or treatment window, that is arranged in or on the housing <NUM> so that the aperture <NUM> can be placed adjacent to or on (e.g. in contact with) the skin of the subject. The treatment device <NUM> includes a light source <NUM> that is for generating light pulses that are to be applied to the skin of the subject via the aperture <NUM> and effect a treatment operation. The light source <NUM> is arranged in the housing <NUM> so that the light pulses are provided from the light source <NUM> through the aperture <NUM>. The aperture/light exit window <NUM> may be in the form of an opening at the head end <NUM> of the housing <NUM>, or it may be in the form of a window (including a waveguide) that is transparent or semi-transparent to the light pulses (i.e. the light pulses can pass through the window).

In the exemplary embodiment shown in <FIG>, the aperture <NUM> has a generally rectangular shape, which results in a generally rectangular-shaped skin treatment region (also referred to herein as a treatment area) on the skin. It will be appreciated that the aperture <NUM> can have any other desired shape. For example, the aperture <NUM> can be square, elliptical, circular, or any other polygonal shape.

The light source <NUM> can generate light pulses of any suitable or desired wavelength (or range of wavelengths) and/or intensities. For example, the light source <NUM> can generate visible light, infrared (IR) light and/or ultraviolet (UV) light. The light source <NUM> can comprise any suitable type of light source, such as a gas discharge lamp, one or more light emitting diodes (LEDs), a laser or lasers, etc..

According to the embodiments herein, the light source is a U-shaped light source, e.g. a U-shaped gas discharge lamp. The gas discharge lamp may comprise a gas in a housing (e.g. a tube), where the gas is typically a noble gas, such as Xenon or Argon, or a mixture of such gases. The gas discharge lamp may be a flash lamp, e.g., a Xenon flash lamp.

The light source <NUM> can provide light pulses with spectral content in the <NUM>-<NUM> nanometre (nm) range for a duration of around <NUM> milliseconds (ms), as these wavelengths heat melanin in the hair and hair root by absorption, which puts the hair follicles in a resting phase, preventing hair regrowth.

The light source <NUM> is configured to provide pulses of light. That is, the light source <NUM> is configured to generate light at a high intensity for a short duration (e.g. less than <NUM> second). The intensity of the light pulse should be high enough to effect the treatment operation on the skin or body part adjacent the aperture <NUM>.

The illustrated treatment device <NUM> also includes two skin contact sensors <NUM>, <NUM> positioned on or in the head portion <NUM> that are used to determine whether the head portion <NUM> is in contact with the skin before a light pulse is generated to avoid the light pulse being directed into the eyes of the user or subject.

The illustrated treatment device <NUM> also includes a skin tone sensor <NUM> positioned on or in the head portion <NUM> that is used to determine a skin tone of the skin that the head portion <NUM> is in contact with.

The illustrated treatment device <NUM> also includes a user control <NUM> that can be operated by the user to activate the treatment device <NUM> so that the head portion <NUM> performs the required treatment operation on the body of the subject (e.g. the generation of one or more light pulses by the light source <NUM>). The user control <NUM> may be in the form of a switch, a button, a touch pad, etc. A user control <NUM> may also be used to switch between different treatment operations.

As noted above, it is desirable for an IPL device to provide both hair removal functionality and skin rejuvenation functionality. It is also desirable to decrease the treatment time for hair removal. However, challenges exist because faster hair removal requires a larger treatment area and/or a faster pulse rate than that used for skin rejuvenation, whereas skin rejuvenation requires higher fluence than that used for hair removal. For a given light source, increasing the treatment area results in lower fluence (i.e. since the emitted light is spread over a larger area). Furthermore, there is limited space within home-use devices that prevents the size of the light source from being significantly increased to enable the required fluence for larger treatment areas. Achieving both a larger treatment area and a higher fluence is therefore challenging.

To address these and other problems, there is provided a treatment device for performing light-based treatment operations on or to a subject. The treatment device could be, for example, the treatment device described with reference to <FIG>. The treatment device according to some embodiments will now be described with reference to <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG>.

<FIG> show a light exit window <NUM> and a light source <NUM> inside a treatment device behind the light exit window <NUM>. The treatment device comprises a U-shaped light source <NUM> for emitting a light pulse. The U-shaped light source <NUM> is illustrated in <FIG>. That is, the part of the light source <NUM> that generates and emits light, is U-shaped. For example, the light source <NUM> may be a U-shaped flash lamp. The light source <NUM> extends generally along a first axis <NUM>. In other words, the first axis <NUM> is the long axis of the U-shaped light source <NUM>. The first axis <NUM> lies generally or substantially exactly in a plane that is parallel to the plane of the light exit window <NUM>.

The light pulse is emitted from the treatment device via the light exit window <NUM>. For example, the light exit window <NUM> could be an opening in the housing of the treatment device, or it could be a transparent or semi-transparent window (including a waveguide). The light exit window <NUM> could be any shape but is shown in <FIG> as being generally rectangular. The part of the treatment device comprising the light exit window <NUM> is placed on or adjacent to the skin during treatment.

The treatment device further comprises a reflector for reflecting the light pulse towards the light exit window <NUM>. The reflector, not shown in <FIG>, is generally positioned around and/or on the opposite side of the light source <NUM> to the light exit window <NUM>. The reflector acts to reflect the light emitted by the light source <NUM> towards the light exit window <NUM>.

The treatment device is configured to operate with the light source <NUM> and the reflector in a first configuration <NUM> for performing hair removal on the subject, and with the light source <NUM> and the reflector in a second configuration <NUM> for performing skin rejuvenation on the subject.

The light source is rotatable about the first axis <NUM> to switch between operating in the first configuration and the second configuration. An example of the U-shaped light source <NUM> in the first configuration <NUM> for performing hair removal is depicted in <FIG>. An example of the U-shaped light source <NUM> in the second configuration <NUM> for performing skin rejuvenation is depicted in <FIG>. In some embodiments, the rotation angle of the U-shaped light source between the first and second configuration is <NUM> degrees about the first axis <NUM>.

The first axis <NUM> of the U-shaped light source <NUM> may be parallel to the light exit window <NUM> (i.e., parallel to the plane of the light exit window <NUM>) in both the first <NUM> and second <NUM> configuration, as shown in <FIG>. In the first configuration <NUM>, the U-shaped light source <NUM> may be orientated such that a plane comprising the U shape of the U-shaped light source <NUM> is parallel to the light exit window <NUM>. This is shown in <FIG>. That is, in the first configuration, the U-shaped light source <NUM> may be orientated such that the two 'arms' of the U are able to emit light directly through the light exit window <NUM>. In the second configuration <NUM>, the U-shaped light source may be orientated such that the plane comprising the U shape of the U-shaped light source is perpendicular to the light exit window <NUM> (i.e., perpendicular to the plane of the light exit window <NUM>). This is shown in <FIG>. That is, in the second configuration, the U-shaped light source <NUM> is orientated such that the U-shape is 'side on' to the skin area to be treated.

The reflector may have a different shape in the first configuration <NUM> to the second configuration <NUM>. In the first configuration <NUM>, the reflector may be configured (e.g., positioned and/or shaped) to reflect light from the light pulse through a first area of the light exit window <NUM>. This first area of the light exit window <NUM> is equal to (or approximately equal to) the treatment area on the skin of a subject on which the hair removal treatment is performed. In the second configuration <NUM>, the reflector may be configured (e.g. positioned and/or shaped) to reflect light from the light pulse through a second area of the light exit window <NUM>. In some embodiments, the second area is smaller than the first area. The smaller treatment area in the second configuration relative to the first configuration for the same light output by the same light source results in a higher fluence being delivered to the skin in the second configuration compared to the first configuration. The second configuration <NUM> is thereby able to provide effective skin rejuvenation. On the other hand, the first area can be larger than in conventional treatment devices to provide faster hair removal treatment, since each light pulse is able to treat a larger area, thereby requiring less pulses to cover the body part or body.

<FIG> illustrate exemplary configurations of a treatment device for performing hair removal, and <NUM>(c) illustrates an exemplary configuration of a treatment device for performing skin rejuvenation in accordance with some embodiments.

<FIG> shows the U-shaped light source <NUM> and the reflector <NUM> in the first configuration <NUM> for performing hair removal in accordance with some embodiments. The U-shaped light source <NUM> extends along the direction of a first axis <NUM> (shown by the dashed line) and is rotatable about the axis <NUM> to switch between configurations. The U-shape of the light source increases the light energy emitted per pulse compared to a single straight light source (e.g., a single tube-shaped light source). Advantageously, a U-shaped light source <NUM> does not take up significantly more space in the head portion of the treatment device than a single straight light source. Indeed, a U-shaped flash lamp can be roughly double the total length of a straight flash lamp whilst fitting into the same sized treatment device. Thus, the U-shaped flash lamp can provide roughly double the total energy output.

The reflector <NUM> is positioned behind the light source <NUM> (from the perspective of the light exit window (not shown) and is configured to reflect the light pulse emitted by the light source <NUM> towards the light exit window. The area of skin that is treated by the direct and reflected light that passes through the light exit window through is referred to herein as the treatment area.

In the first configuration <NUM>, the light source <NUM> and reflector <NUM> are configured to deliver the required fluence for hair removal across a larger treatment area than existing devices, and thus provide faster treatment time for a body part that requires multiple light pulses to fully treat. For example, if the light source <NUM> in the disclosed treatment device according to a specific embodiment is double the length of a light source in an existing treatment device, then the treatment area of the disclosed treatment device can be twice the size whilst still maintaining the required fluence for hair removal treatment. Consequently, the treatment time with the disclosed device according to the specific embodiment can be half that of the existing treatment device.

In some embodiments, the reflector <NUM> is segmented to allow the shape of the reflector <NUM> to be changed between configurations. The segments <NUM> of the reflector <NUM> extend parallel to the direction of the first axis <NUM>, i.e., along the same direction that the U-shaped light source <NUM> extends. In the first configuration shown in <FIG>, the segments <NUM> in the reflector <NUM> are configured so that they form a generally parabolic shape suitable for directing the light from the U-shaped light source <NUM> towards the light exit window. In this illustrated embodiment, the segments <NUM> are connected to neighbouring segments <NUM> via hinges <NUM> that enable the segments <NUM> to move relative to each other, and enable the configuration of the reflector <NUM> to change.

<FIG> illustrates a first configuration <NUM> for performing hair removal according to an alternative embodiment in which a different configuration of the reflector <NUM> is used. In this alternative first configuration, although the light source <NUM> has the same shape and orientation as the light source <NUM> in <FIG>, rather than forming a generally parabolic shape, the segmented reflector <NUM> forms an 'M' or 'W' shape, with different segments <NUM> of the U-shaped light source <NUM> reflecting the light from one of the 'arms' of the U-shaped light source. This shape (combined with the configuration/orientation of the light source <NUM>) improves the uniformity of the reflected light across the treatment area.

<FIG> illustrates a second configuration <NUM> of the treatment device for performing skin rejuvenation according to some embodiments. The light source <NUM> is rotated <NUM> degrees about the first axis <NUM> relative to the orientation of the light source <NUM> in <FIG>. In this orientation the U-shaped light source can be considered to be 'side on' to the light exit window (whereas in the first configuration the U-shaped light source can be considered to be 'front on' to the light exit window). In some embodiments, the light source <NUM> is also spaced further from the light exit window compared to its position in the first configuration, e.g., <FIG>. The reflector <NUM> is configured (e.g., positioned and/or shaped) in the second configuration <NUM> to reflect the light pulse emitted by the light source <NUM> onto a smaller treatment area than in the first configuration <NUM>, <NUM>, thereby increasing the fluence in that treatment area compared to the area treated in the first configuration. As in the exemplary first configurations in <FIG>, the segments <NUM> in the reflector <NUM> are configured so that they form a generally parabolic shape. However, the parabolic shape is different in view of the different orientation of the U-shaped light source <NUM>, and acts to reflect the light from the U-shape light source <NUM> towards the light exit window. Concentrating the light from the U-shape light source <NUM> into a smaller treatment area provides a higher fluence, as required for skin rejuvenation treatment.

The first configurations <NUM>, <NUM> and second configurations <NUM> may be such that, for a given light pulse energy, the light pulse in the second configuration <NUM> delivers a higher fluence at the light exit window than the light pulse in the first configuration <NUM>, <NUM>.

Although in the above embodiments the reflector <NUM> comprises a plurality of reflecting segments <NUM> that are connected together via hinges <NUM> to enable the configuration of the reflector <NUM> to be changed, those skilled in the art will appreciate that the reflector can have a different construction. For example, the reflector <NUM> can be a flexible material, e.g. a metallic sheet or a non-reflective flexible material with a reflective coating, that can be manipulated or directed by a suitable mechanism into the required reflector shape for the particular configuration. As another example, the reflector <NUM> can be formed from a shape-changing material that can be controlled to change between the shapes required for the first and second configurations in response to an electrical signal or other suitable stimulus.

As noted above, the treatment device is configured to operate with the light source and the reflector in a first configuration for performing hair removal on the subject, and in a second configuration for performing skin rejuvenation on the subject. To enable the required treatment mode to be provided, the treatment device comprises a mechanism or other means for enabling the treatment device to switch between configurations. Some exemplary mechanisms are described below, but those skilled in the art will be aware of a variety of different types of mechanisms that can be used to cause the desired configuration change.

In some embodiments, the treatment device comprises a mechanical system for moving the reflector and the light source between the first and second configuration. For example, a system of gear wheels and connection rods may be used to move the reflector and the light source.

In some embodiments, the U-shaped light source may be connected to a main gear wheel that can rotate the light source about the first axis to move the device between the first and second configurations. When the main gear wheel rotates, the light source (e.g. the lamp head) switches between two working modes, i.e. the first and second configuration. In some embodiments, the mechanical system may also translate the light source (e.g. the lamp head) towards the light exit window when it switches to the first configuration for hair removal. This is because, when the light source is rotated from the second configuration into the first configuration, space is created between the light source and the light exit window. By moving the light source closer to the light exit window, the energy of the light pulse is more efficiently transferred to the skin of the subject during treatment. Each connection joint (e.g. hinge) between any two segments of the segmented reflector may be linked to one or more sub-gears via one or more connection rods. These sub-gears can be used to move the reflector between the first and second configurations.

In some embodiments, the treatment device can be changed between the two configurations with one or more manual movements performed by the user of the treatment device. For example, the treatment device can be changed between the two configurations when the user rotates a switch on the treatment device.

In alternative embodiments, the device comprises a motor for moving the reflector and the light source between the first and second configuration. The motor may be controlled by the user, e.g., via a user control button or switch.

In some embodiments, a hair removal filter can be placed in front of the light source in the first configuration, and a skin rejuvenation filter can be placed in front of the light source in the second configuration. The filters may be of different sizes corresponding to the different treatment area sizes and/or the filters can pass different wavelengths of light depending on the treatment mode (hair removal or skin rejuvenation). There may be a mechanical system for ensuring the required filter is in front of the light source in the first and second configuration, but alternatively, the filters can be manually changed (including by removing one filter and replacing it with the filter for the desired configuration).

<FIG> and (c) illustrate an exemplary mechanism for enabling a treatment device to switch between the first configuration and the second configuration. <FIG> show a treatment device <NUM> that includes a mechanism <NUM> for enabling the treatment device <NUM> to switch between the first configuration for hair removal (shown in <FIG>) and the second configuration for skin rejuvenation (shown in <FIG>). As in the embodiments shown in <FIG>, the treatment device <NUM> comprises a rotatable U-shaped light source <NUM>, a reflector <NUM> that comprises a plurality of segments <NUM> connected together via hinges <NUM>.

The mechanism <NUM> comprises a motor <NUM> that drives the switch between the configurations. As shown in <FIG>, the axle <NUM> of the motor can rotate one way to drive a centre rod <NUM> in a first direction (downwards in the perspective of <FIG>) to switch to the first configuration, and rotate the opposite way to drive the centre rod <NUM> in the opposite direction (upwards in the perspective of <FIG>). An arrangement of rods <NUM> is connected to the ends of the reflector <NUM> and connected to the centre rod <NUM> at a connection point <NUM>, so that movement of the centre rod <NUM> by the motor <NUM> causes the movement of the rods in the rod arrangement <NUM> and thus a change of the shape of the reflector <NUM>. The movement of rods in the rod arrangement <NUM> is guided by a guide rail <NUM>, to which two rods are connected, and two wheels <NUM>, to which other rods are connected. The guide rail <NUM> and wheels <NUM> guide the movement of the rods <NUM> to provide the required shape to the reflector <NUM> as the motor <NUM> is operated to switch between configurations. As the motor <NUM> operates to move centre rod <NUM>, it also rotates the light source <NUM> degrees around centre axis <NUM>.

Therefore, there is disclosed herein a treatment device comprising a U-shaped light source and a reflector. The light source and reflector can be in a first configuration for hair removal, and in a second configuration for skin rejuvenation. The treatment device provides both faster hair removal and effective skin rejuvenation within the same device.

Claim 1:
A treatment device (<NUM>; <NUM>) for performing light-based treatment operations on or to a subject, the treatment device (<NUM>; <NUM>) comprising:
a U-shaped light source (<NUM>; <NUM>; <NUM>; <NUM>) extending along a first axis (<NUM>; <NUM>) for emitting a light pulse;
a light exit window (<NUM>; <NUM>) through which the light pulse is emitted from the treatment device (<NUM>; <NUM>); and
a reflector (<NUM>; <NUM>) for reflecting the light pulse towards the light exit window (<NUM>; <NUM>);
wherein the treatment device (<NUM>; <NUM>) is configured such that the light source (<NUM>; <NUM>; <NUM>; <NUM>) and the reflector (<NUM>; <NUM>) have a first operating configuration (<NUM>; <NUM>, <NUM>) for performing hair removal on the subject, and the light source (<NUM>; <NUM>; <NUM>; <NUM>) and the reflector (<NUM>; <NUM>) have a second operating configuration (<NUM>; <NUM>) for performing skin rejuvenation on the subject;
characterized in that the light source (<NUM>; <NUM>; <NUM>; <NUM>) is rotatable about the first axis (<NUM>; <NUM>) to switch between operating in the first configuration (<NUM>; <NUM>, <NUM>) and the second configuration (<NUM>; <NUM>).