Abstract: A laser sensor module for detecting a particle density of small particles with a particle size between 0.05 ?m and 10 ?m includes a first laser configured to emit a first measurement beam, a second laser configured to emit a second measurement beam, and an optical arrangement configured to focus the first measurement beam to a first measurement volume and to focus the second measurement beam to a second measurement volume. The optical arrangement includes a first numerical aperture and a second numerical aperture arranged to detect a predetermined minimum particle size. The laser sensor module further includes a first detector configured to determine a first self-mixing interference signal of a first optical wave, a second detector configured to determine a second self-mixing interference signal of a second optical wave, and an evaluator.

Abstract: A method (300) for detecting one or more caries using an imaging device (10), the method including the steps of: (i) directing (320) light from a first light source (12) toward a tooth (40); (ii) measuring (340), with an optical sensor (16), transmission of light from the first light source through the tooth; (iii) directing (330) light from a second light source (14) toward the tooth, wherein the second light source directs light at the tooth at a different angle relative to the first light source; (iv) measuring (350), with the optical sensor, reflectance from the tooth of light from the second light source; (v) comparing (360) the measured transmission to the measured reflectance; and (vi) determining (370), based at least in part on said comparison, whether a caries is present in the tooth.

Abstract: A laser sensor module measures a particle density of particles with a size of less than 20 ?m. The laser sensor module includes: a laser configured to emit a laser beam; a detector; and an optical arrangement. The optical arrangement is configured to focus the laser beam to a focus region. The laser is configured to emit the laser beam through the optical arrangement to the focus region. The optical arrangement has an emission window. The detector is configured to determine an interference signal of an interference of reflected laser light with emitted later light of the laser beam. The laser sensor module is configured to provide an indication signal of a soiling of the emission window based on the interference signal determined during a mechanical excitation of the emission window.

Abstract: The invention describes a laser sensor or laser sensor module (100) using self-mixing interference for particle density detection, a related method of particle density detection and a corresponding computer program product. The invention further relates to devices comprising such a laser sensor or laser sensor module. It is a basic idea of the present invention to detect particles by means of self-mixing interference signals and determine a corresponding particle density. In addition at least a first parameter related to at least one velocity component of a velocity vector of the particles is determined in order to correct the particle density if there is the relative movement between a detection volume and the particles. Such a relative movement may for example be related to a velocity of a fluid transporting the particles (e.g. wind speed). Furthermore, it is possible to determine at least one velocity component of the velocity of the particles based on the self-mixing interference signals.

Abstract: A laser sensor module includes a laser diode configured emit a laser beam, an electrical driver configured to supply the laser diode with a driving current to stimulate emission of the laser beam, a detector, and an optical arrangement configured to focus the laser beam to a focus region. The laser diode is arranged to emit the laser beam through the optical arrangement to the focus region. The optical arrangement comprises an emission window. The detector is arranged to determine an interference signal. The laser sensor module comprises a soiling detection unit configured to vary a wavelength of the laser beam with a variation amplitude over a predetermined time period to provide a soiling detection signal indicative of a soiling of the emission window based on an interference signal during the wavelength variation of the laser beam.

Abstract: A laser sensor for detecting a particle density includes: a laser configured to emit a measurement beam, an optical arrangement being arranged to focus the measurement beam to a measurement volume, the optical arrangement having a numerical aperture with respect to the measurement beam, a detector configured to determine a self-mixing interference signal of a optical wave within a laser cavity of the laser, and an evaluator. The evaluator is configured to: receive detection signals generated by the detector in reaction to the determined self-mixing interference signal, determine an average transition time of particles passing the measurement volume in a predetermined time period based on a duration of the self-mixing interference signals generated by the particles, determine a number of particles based on the self-mixing interference signals in the predetermined time period, and determine the particle density based on the average transition time and the number of particles.

Abstract: The invention describes a laser sensor module (100) for detecting ultra-fine particles (10) with a particle size of 300 nm or less, more preferably 200 nm or less, most preferably 100 nm or less, the laser sensor module (100) comprising: —at least one laser (110) being adapted to emit laser light to at least one focus region in reaction to signals provided by at least one electrical driver (130), —at least one detector (120) being adapted to determine a self-mixing interference signal of an optical wave within a laser cavity of the at least one laser (110), wherein the self-mixing interference signal is caused by reflected laser light reentering the laser cavity, the reflected laser light being reflected by a particle receiving at least a part of the laser light, —the laser sensor module (100) being arranged to perform at least one self-mixing interference measurement, —the laser sensor module (100) being adapted to determine a first particle size distribution function with a first sensitivity by means of at

Abstract: A laser sensor module for detecting a particle density of particles, which includes: a laser; a detector; and a mirror. The laser is arranged to emit a laser beam to the mirror. A movement of the mirror is arranged to redirect the laser beam. The laser beam is displaced with respect to a rotation axis of the mirror such that a focus region of the laser beam is moving with a velocity having components normal and parallel to the optical axis of the redirected laser beam such that an angle between the parallel and the normal velocity component is at least a threshold angle of 2°. The detector is arranged to determine a self mixing interference signal of an optical wave within a laser cavity of the laser, the self mixing interference signal being generated by laser light of the laser beam reflected by at least one of the particles.

Abstract: A method of measuring a particle density of particles includes emitting, by a laser, a laser beam directed to a mirror, redirecting the laser beam by the mirror with a predetermined periodic movement, and focusing the laser beam to a detection volume by an optical imaging device. The method further includes determining a self mixing interference signal of an optical wave within a laser cavity if the self mixing interference signal is generated by laser light of the laser beam reflected by at least one of the particles and suppressing a false self mixing interference signal for particle detection if the self mixing interference signal is caused by a disturbance in an optical path of the laser beam. The false self mixing signal caused by the disturbance in the optical path of the laser beam is suppressed in a defined range of angles of the mirror during the periodic movement.

Abstract: A laser sensor module measures a particle density of particles with a size of less than 20 ?m. The laser sensor module includes: a laser configured to emit a laser beam; a detector; and an optical arrangement. The optical arrangement is configured to focus the laser beam to a focus region. The laser is configured to emit the laser beam through the optical arrangement to the focus region. The optical arrangement has an emission window. The detector is configured to determine an interference signal of an interference of reflected laser light with emitted later light of the laser beam. The laser sensor module is configured to provide an indication signal of a soiling of the emission window based on the interference signal determined during a mechanical excitation of the emission window.

Abstract: A toothbrush (10) includes a brushhead (18), a first force sensor (30A) for measuring a first force exerted by the brushhead at a first angle relative to a tooth and a second force sensor (30B) for measuring a second force exerted by the brushhead at a second angle relative to the tooth, the second angle being different than the first angle, and a processing unit (26). The processing unit is structured to: (i) receive first information indicative of the first force as measured by the first force sensor, (ii) receive second information indicative of the second force as measured by the second force sensor, and (iii) determine information regarding a current brushing angle of the brushhead based on the first information and the second information.

Abstract: The invention describes a laser sensor module (100) for particle density detection. The laser sensor module (100) comprising at least one first laser (110), at least one first detector (120) and at least one electrical driver (130). The first laser (110) is adapted to emit first laser light in reaction to signals provided by the at least one electrical driver (130). The at least one first detector (120) is adapted to detect a first self-mixing interference signal of an optical wave within a first laser cavity of the first laser (110). The first self-mixing interference signal is caused by first reflected laser light reentering the first laser cavity, the first reflected laser light being reflected by a particle receiving at least a part of the first laser light. The laser sensor module (100) is adapted to reduce multiple counts of the particle. The invention further describes a related method and computer program product.

Abstract: The invention describes a laser sensor module (100) for detecting ultra-fine particles (10) with a particle size of 300 nm or less, more preferably 200 nm or less, most preferably 100 nm or less, the laser sensor module (100) comprising: —at least one laser (110) being adapted to emit laser light to at least one focus region in reaction to signals provided by at least one electrical driver (130),—at least one detector (120) being adapted to determine a self-mixing interference signal of an optical wave within a laser cavity of the at least one laser (110), wherein the self-mixing interference signal is caused by reflected laser light reentering the laser cavity, the reflected laser light being reflected by a particle receiving at least a part of the laser light,—the laser sensor module (100) being arranged to perform at least one self-mixing interference measurement,—the laser sensor module (100) being adapted to determine a first particle size distribution function with a first sensitivity by means of at lea

Abstract: The invention describes a laser sensor module (100) for particle size detection. The laser sensor module (100) comprises at least one first laser (110), at least one first detector (120), at least one electrical driver (130) and at least one evaluator (140). The first laser (110) is adapted to emit first laser light in reaction to signals provided by the at least one driver (130). The at least one first detector (120) is adapted to determine a first self-mixing interference signal (30) of an optical wave within a first laser cavity of the first laser (110). The first self-mixing interference signal (30) is caused by first reflected laser light reentering the first laser cavity, the first reflected laser light being reflected by a particle receiving at least a part of the first laser light.

Abstract: A method (300) for detecting one or more caries using an imaging device (10), the method including the steps of: (i) directing (320) light from a first light source (12) toward a tooth (40); (ii) measuring (340), with an optical sensor (16), transmission of light from the first light source through the tooth; (iii) directing (330) light from a second light source (14) toward the tooth, wherein the second light source directs light at the tooth at a different angle relative to the first light source; (iv) measuring (350), with the optical sensor, reflectance from the tooth of light from the second light source; (v) comparing (360) the measured transmission to the measured reflectance; and (vi) determining (370), based at least in part on said comparison, whether a caries is present in the tooth.

Abstract: Attachment assemblies for oral hygiene devices and, in particular, attachment assemblies having improved designs to more effectively clean an individual's tongue or other inter-oral surface are described herein. These improved attachment assembly correspond, amongst other aspects, to improved fluid chamber configurations, improved fluid channel configurations, improved fluid exit hole configurations, improved air inlet hole configuration, and air channel features. Furthermore, these improvements to attachment assemblies are capable of being implemented separately from, or in combination with, one another.

Abstract: A method of measuring a particle density of particles includes emitting, by a laser, a laser beam directed to a mirror, redirecting the laser beam by the mirror with a predetermined periodic movement, and focusing the laser beam to a detection volume by an optical imaging device. The method further includes determining a self mixing interference signal of an optical wave within a laser cavity if the self mixing interference signal is generated by laser light of the laser beam reflected by at least one of the particles and suppressing a false self mixing interference signal for particle detection if the self mixing interference signal is caused by a disturbance in an optical path of the laser beam. The false self mixing signal caused by the disturbance in the optical path of the laser beam is suppressed in a defined range of angles of the mirror during the periodic movement.

Abstract: A laser sensor module for detecting a particle density of particles, which includes: a laser; a detector; and a mirror. The laser is arranged to emit a laser beam to the mirror. A movement of the mirror is arranged to redirect the laser beam. The laser beam is displaced with respect to a rotation axis of the mirror such that a focus region of the laser beam is moving with a velocity having components normal and parallel to the optical axis of the redirected laser beam such that an angle between the parallel and the normal velocity component is at least a threshold angle of 2°. The detector is arranged to determine a self mixing interference signal of an optical wave within a laser cavity of the laser, the self mixing interference signal being generated by laser light of the laser beam reflected by at least one of the particles.

Abstract: A laser sensor for detecting a particle density includes: a laser configured to emit a measurement beam, an optical arrangement being arranged to focus the measurement beam to a measurement volume, the optical arrangement having a numerical aperture with respect to the measurement beam, a detector configured to determine a self-mixing interference signal of a optical wave within a laser cavity of the laser, and an evaluator. The evaluator is configured to: receive detection signals generated by the detector in reaction to the determined self-mixing interference signal, determine an average transition time of particles passing the measurement volume in a predetermined time period based on a duration of the self-mixing interference signals generated by the particles, determine a number of particles based on the self-mixing interference signals in the predetermined time period, and determine the particle density based on the average transition time and the number of particles.

Abstract: A powered oral care apparatus (2) has a pump-free fluid delivery system for delivering one or more fluids to the oral cavity of a user. The oral care apparatus may employ an oral care assembly (30) that has a capsule member (38) for delivering fluid through a number of openings (31, 46) in response to movement of a head (4) of the oral care apparatus. The oral care apparatus may also employ an oral care assembly (62) having a diaphragm member (84) and a mass member (88) coupled thereto wherein, in response to motion being imparted to the brushhead, the mass member and diaphragm member generate a pumping force to cause fluid to be delivered out of the oral care assembly.