A device for the treatment of skin by radiation pulses. The device has a detector measuring a biophysical property of skin, such as temperature increase, dispersion or absorption coefficient, or reflection coefficient for light having a predetermined wavelength, and also has a control unit which determines, from the biophysical property, a safe dose of radiation. The device automatically protects against an overdose from the radiation source. The invention can be used, not only in a hair removing device such as a laser epilator, a laser shaver or a flashlight epilator, but also in devices for the medical treatment of skin by means of radiation, such as photodermatology systems.
The present invention relates to a portable laser treatment device, comprising case (10), semiconductor laser diode (11) which is installed inside the case (10) and irradiates laser, condensing lens (12) which is installed in front of the semiconductor laser diode (11), power supply, power switch (30) which is installed outside the case (10) and controls the supply of power, irradiation switch (31) which controls the irradiation of laser and controller (32) which controls the operation of the device according to the state of to switches, wherein distance detecting sensor (40) is installed on the case (10) to measure the distance between an irradiated surface and condensing lens (12) and said controller (32) receives signal from the distance detecting sensor (40) and cuts off laser irradiation when the distance between the irradiated surface and condensing lens (12) is greater than focal distance of the condensing lens (12).
A hair-removing device (1) includes a laser source (3), an adjustable laser beam manipulator (5) for positioning a laser beam (7) of the laser source (3) in a target position (9) on a skin (11) to be treated, and an image sensor (47) for detecting an image (49) of the skin. The hair-removing device further comprises a control unit (17) which determines a position and orientation on the skin of a hair (13) to be removed, and which determines the target position of the laser beam as a function of said position and orientation of the hair. The control unit brings the laser beam manipulator in a state corresponding to the target position of the laser beam, and activates the laser source when the laser beam manipulator has reached said state. Thus, the hair-removing device is suitable for use by inexperienced users, and is particularly suitable for the consumer market. In a particular embodiment, the control unit determines the target position of the laser beam in a position (71) on the skin under which a root (15) of the hair is present, so that the root of the hair is destroyed and the hair-removing device (1) is an epilating device by means of which the hair is removed for a relatively long time or even permanently. In another embodiment, the control unit determines the target position of the laser beam in a position (65) on the hair where the hair comes out of the skin, so that the hair is burnt through near the skin surface and the hair-removing device (1'') is a shaving device by means of which a high skin smoothness is obtained.
A sensor for detecting the presence of skin is disclosed, one configuration of which uses multiple light emitting diodes, each of a unique wavelength band, and a broad-band photodetector to measure the remission of light at multiple wavelengths from a material being analyzed. Characteristics of the spectral remission of the material are used to discriminate human skin from materials that are not human skin. Further, an aesthetic medical device utilizing such a sensor in which the device is inhibited from operation if skin has not been detected. The incorporation of a skin sensor improves the safety of devices that emit radiation that otherwise would pose a hazard if not directed onto skin.
