Abstract: There is provided a cutting element for use in a hair cutting device. The cutting element includes an optical waveguide having an optical axis and a sidewall, wherein a portion of the sidewall forms a cutting face for contacting hair; wherein the optical waveguide includes a plurality of structures formed along the optical axis, the structures having a refractive index which is different to a refractive index of the optical waveguide. A hair cutting device comprising a cutting element, and a method of manufacturing an optical waveguide cutting element are also disclosed.

Abstract: There is provided a hair cutting device a hair cutting device for cutting hair on a subject, the hair cutting device comprising a light source for generating light at one or more specific wavelengths corresponding to wavelengths absorbed by one or more chromophores in or on hair; a cutting element that comprises an optical waveguide that is coupled at a first end to the light source to receive light, wherein a portion of a sidewall of the optical 5 waveguide forms a cutting face for contacting hair; and a control unit that is coupled to the light source, wherein the control unit is configured to vary the power of the light generated by the light source between first and second power levels during operation such that, on heating of a hair by light coupling from a contact point on the cutting face into the hair, the temperature of the contact point on the cutting face is maintained below a glass transition 10 temperature for the optical waveguide, wherein the first power level is higher than the second power le

Abstract: There is provided a cutting assembly for use in a hair cutting device. The cutting assembly includes a cutting element having a first end and a second end, the cutting element comprising an optical waveguide for receiving light from at least one light source. The cutting assembly includes a first light guiding element configured to guide light from the at least one light source into the first end of the cutting element, and a second light guiding element configured to guide light from the at least one light source into the second end of the cutting element. Each of the light guiding elements comprises a taper transition section in which a diameter of the light guiding element reduces from a first diameter to a second diameter. A hair cutting device comprising a cutting assembly is also disclosed.

Abstract: A hair cutting device for cutting hair on a body of a subject is presented. The hair cutting device comprises a laser light source, a light guiding element for guiding light from the light source to the cutting element. The cutting element comprises an optical waveguide for receiving light from the light guiding element. The light guiding element has a tapered section in which a diameter of the light guiding element reduces from a light source side diameter to a cutting element side diameter. A portion of a sidewall of the optical waveguide of the cutting element forms a cutting face for contacting hair.

Abstract: There is provided a hair cutting device for cutting hair on a body of a subject, the hair cutting device comprising a light source for generating light at one or more specific wavelengths corresponding to wavelengths absorbed by one or more chromophores in or on hair; a cutting element that comprises an optical waveguide that is coupled at a first end to the light source to receive light, wherein a portion of a sidewall of the optical waveguide forms a cutting face for contacting hair; and a control unit that is coupled to the light source, wherein the control unit is configured to receive an input relating to a region of the body on which hair is to be cut and/or a speed of movement of the hair cutting device, and to control the power of the light generated by the light source based on the received input.

Abstract: There is provided a hair cutting device for cutting hair on a body of a subject, the hair cutting device comprising a source for generating light at one or more specific wavelengths corresponding to wavelengths absorbed by one or more chromophores in or on hair; a cutting element that comprises an optical waveguide that is coupled at a first end to the source to receive light, wherein a portion of a sidewall of the optical waveguide forms a cutting face for contacting hair; a sensor for measuring a force acting on the cutting element; and a control unit that is coupled to the source and the sensor, wherein the control unit is configured to control the power of the light generated by the source based on the measured force, and wherein the power of the light is controlled to a first non-zero level if the measured force is below a first threshold, and controlled to a second non-zero level if the measured force is above a second threshold, wherein the first non-zero level is less than the second non-zero level an

Abstract: There is provided a guard structure for use in a hair cutting device for cutting hair on a body of a subject, the guard structure comprising one or more guard elements, wherein the one or more guard elements are arranged such that in use in the hair cutting device the one or more guard elements space an optical waveguide in the hair cutting device from the skin of the subject, and wherein the one or more guard elements are shaped and/or formed to minimise or reduce the coupling of light from the optical waveguide to the guard structure.

Abstract: There is provided a cutting element for use in a hair cutting device. The cutting element comprises an optical waveguide having a sidewall, wherein a portion of the sidewall forms a cutting face for contacting hair. The cutting element also comprises a hair support structure configured to restrict lateral movement of a hair in contact with the cutting face, relative to the optical waveguide. The hair support structure comprises a plurality of movement restrictors extending from the cutting face. Each movement restrictor comprises a ridge protruding from the cutting face of the optical waveguide, these ridges are arranged parallel to one another. A hair support structure for use with a cutting element, and a hair cutting device including such a cutting element are also disclosed.

Abstract: There is provided a cutting element for use in a hair cutting device. The cutting element comprises an optical waveguide having a sidewall which is substantially parallel to the longitudinal axis of the optical waveguide, wherein a portion of the sidewall forms a cutting face for contacting hair. The cutting face has a structure comprising a plurality of indentations configured to allow light to couple out through the sidewall to increase the amount of light able to couple to hair. A hair cutting device comprising a light source and the cutting element is also provided.

Abstract: There is provided a hair cutting device for cutting hair on a body of a subject, the hair cutting device comprising a light source for generating laser light at one or more specific wavelengths corresponding to wavelengths absorbed by one or more chromophores in or on hair; and a cutting element that comprises an optical waveguide that is coupled to the light source to receive laser light, wherein a portion of a sidewall of the optical waveguide forms a cutting face for contacting hair; wherein at least a portion of the cutting face is provided with a first coating or layer that is formed from or comprises a lipophilic material; and wherein at least a portion of the sidewall of the optical waveguide that can contact the skin of the subject has a second coating or layer that is formed from or comprises a lipophobic material.

Abstract: There is provided a hair cutting device for cutting hair on a body of a subject, the hair cutting device comprising a light source for generating laser light at one or more specific wavelengths corresponding to wavelengths absorbed by one or more chromophores in hair; and a cutting element that comprises an optical waveguide that is coupled to the light source to receive laser light, wherein a portion of a side wall of the optical waveguide forms a cutting face for contacting hair, and wherein at least at the cutting face the optical waveguide has a refractive index that is equal to or lower than the refractive index of hair and higher than the refractive index of skin.

Abstract: Hair growth stimulating device to obtain a non-chemical hair growth stimulation comprising an ultrasound transducer (UST), and a driver (DE) for the ultrasound transducer, wherein the driver is arranged for having the ultrasound transducer (UST) generate an ultrasound signal having a frequency not exceeding 100 kHz, preferably 20 kHz, at a power not exceeding 500 mW/cm2, preferably 250 mW/cm2. The frequency may be subject to a frequency sweep not exceeding 20%, preferably 10%. Pulses having a pulse width between 10 ms and 500 ms may be used.

Abstract: A hair styler uses ultrasound at an ultrasound frequency of at least 1 MHz to get a non-chemical hair styling. Advantageously, the ultrasound frequency is between 1 and 100 MHz, preferably between 3 and 10 MHz, and more preferably between 3 and 5 MHz. The ultrasound energy is preferably applied at a power that is at least 1 W/cm2, and preferably does not exceed 10 W/cm2, such as 6 W/cm2. The invention may be used for hair curling and for hair straightening. A hair straightening method comprises temporarily straightening hair, and applying ultrasound to temporarily straightened hair to obtain straightened hair. Advantageously, ultrasound is applied during a period of between 5 seconds and 2 minutes, and preferably during about 10 seconds.

Abstract: The present application relates to an optical system (1) comprising a light beam generator (10) configured to generate a light beam (2) and direct it along an optical path (3), an optical element (19, 24) in said optical path (3) and on which said light beam (2) is incident for redirecting said light beam (2), a sensor (4, 5) attached to said optical element (19, 24), the sensor (4, 5) being configured to generate information indicative of a characteristic of said light beam (2) that is incident on said optical element (19, 24), and a controller (6) configured to adjust one or more characteristics of said optical system (1) in dependence on the information generated by said sensor (4, 5).

Abstract: A laser-based hair cutting device (10) comprises a laser source (18), an optically transparent exit window (15) and optical elements (11, 12, 13, 14). The laser source (18) provides an incident light beam (21) for cutting a hair (22) above and near a skin surface by laser-induced optical breakdown (LIOB) of the hair (22) in a focal position of the light beam (21). The optically transparent exit window has an external exit surface (15) for allowing the incident light beam (21) to leave the device. The optical elements (11, 12, 13, 14) focus the incident light beam (21) in the focal position at a working distance from the exit surface (15).

Abstract: A laser-based hair cutting device (10) is provided, which device (10) comprises a laser source (18), an optically transparent exit window (15) and optical elements (11, 12, 13, 14) The laser source (18) provides an incident light beam (21) for cutting a hair (22) above and near a skin surface by laser-induced optical breakdown (LIOB) of the hair (22) in a focal position of the light beam (21). The optically transparent exit window has an external exit surface (15) for allowing the incident light beam (21) to leave the device. The optical elements (11, 12, 13, 14) focus the incident light beam (21) in the focal position at a working distance from the exit surface (15).

Abstract: A skin treatment system comprising a light based skin treatment device (10, 20, 30) is provided. The device (10, 20, 30) comprises a treatment light source (18) for providing a treatment light beam (21) for treating hair or skin tissue, a transparent exit window (14) for allowing the treatment light beam (21) to leave the device (10, 20, 30), and an exit location control unit (17) for controlling a position for the treatment light beam (21) to pass through the exit window (14). The system further comprises a detection light source for providing a detection light beam.

Abstract: A device for analyzing a material, the device having a photo acoustic generator (40) for generating pressure waves in the material by pulsed illumination by a light source, and a sensor (20, 30, 50) for producing a signal using self mixing interferometry, the signal representing displacements of the material due to the pressure waves, and a signal processor (60) for processing the signal to analyze the material. This combination of photo acoustic stimulation and self mixing interferometry sensing helps reduce or avoid errors or distortions caused by sensor contact on the material, and can provide a better ratio of sensitivity for a given degree of compactness of the device.

Abstract: A perfusion, regulation device (10) for regulating tissue perfusion at a target site (2) on a human or animal body. The perfusion regulation device (10) comprises a pressure regulator (4) for determining and regulating pressure exerted by the perfusion regulation device (10) on the target site (2) and a perfusion monitor (5) for measuring tissue perfusion at the target site (2). The perfusion regulation device (10) furthermore comprises a control system (6) for driving the pressure regulator (4) so as to regulate pressure exerted by the perfusion regulation device (10) to the target site (2) thereby using feedback from the perfusion monitor (5). There is also a method for making such a perfusion regulation device (10) and a method for regulating tissue perfusion at a target site (2) on a human or animal body using such a perfusion regulation device (10).