A sensor includes a first element part having a first member and a first element. The first member is a acoustic tubular waveguide and extends along a first direction. The acoustic tubular waveguide includes a first opening and a second opening. A direction from the second opening toward the first opening is along the first direction. The first element includes a vibratile first membrane, and a first supporter supporting the first membrane. The second opening is between the first opening and the first membrane in the first direction. The sensor may be a Piezoelectric Micro electro mechanical systems Ultrasonic Transducer and may be used for inspecting paper and/or resin including detecting thickness of a fed through banknote and/or the presence of foreign matter thereon such as tape. An optical element may alternatively measure the vibration of a membrane from acoustic through transmission instead of an acoustic receiver.

A front end structure of a vehicle body may include: a horn; a bumper cover; an inner grille disposed between the horn and the bumper cover, and a megaphone including a megaphone wall defining a megaphone opening extending along a direction along which the horn and the bumper cover are aligned, wherein a first opening end of the megaphone opposes the horn, a second opening end of the megaphone opposes the bumper cover, and the megaphone is integrated with the inner grille.

Acoustic loudspeaker (10) comprising a cabinet (12) extending in a direction (L), and a speaker (14) defining an acoustic axis (X). The cabinet defines a first axis (V1) perpendicular to the direction, and a second axis (V2) perpendicular to the direction and to the first axis.

The acoustic loudspeaker is intended to be used in a first configuration, wherein the first axis is essentially vertical, and a second configuration, wherein the second axis is essentially vertical.

The speaker is movable relative to the cabinet around an axis of rotation (D) between a first position, wherein the acoustic axis defines with the second axis a first angle less than 30°, and a second position, in which the acoustic axis defines with the first axis (V1) a second angle less than 30°. The axis of rotation makes two angles between 40° and 50° with the first axis and the second axis.

A sound transducer has a diaphragm cup, a transducer element, and a housing, the diaphragm cup having a diaphragm and a wall. The diaphragm, the wall, and at least one housing part are formed in one piece as a fiber-plastic composite component. At least one first region of the fiber-plastic composite component is reinforced with fibers, and at least one second region of the fiber-plastic composite component is free of fibers, so that waves in the fiber-plastic composite component are at least partly reflected at a transition from the at least one first region to the at least one second region.

A sound transducer has a diaphragm cup, a transducer element, and a housing, the diaphragm cup having a diaphragm and a wall. The diaphragm, the wall, and at least one housing part are formed in one piece as a fiber-plastic composite component. At least one first region of the fiber-plastic composite component is reinforced with fibers, and at least one second region of the fiber-plastic composite component is free of fibers, so that waves in the fiber-plastic composite component are at least partly reflected at a transition from the at least one first region to the at least one second region.

A package design for a micromachined ultrasound transducer (MUT) utilizing curved geometry to control the presence and frequency of acoustic resonant modes is described. The approach consists of reducing in number and curving the reflecting surfaces present in the package cavity to adjust the acoustic resonant frequencies to locations outside the band of interest. The design includes a cavity characterized by a curved geometry and a MUT mounted to a side of a substrate facing the cavity with a sound emitting portion of the MUT facing an opening in the substrate. The substrate is disposed over an opening of the cavity with the substrate oriented such that the MUT located within the cavity.

A package design for a micromachined ultrasound transducer (MUT) utilizing curved geometry to control the presence and frequency of acoustic resonant modes is described. The approach consists of reducing in number and curving the reflecting surfaces present in the package cavity to adjust the acoustic resonant frequencies to locations outside the band of interest. The design includes a cavity characterized by a curved geometry and a MUT mounted to a side of a substrate facing the cavity with a sound emitting portion of the MUT facing an opening in the substrate. The substrate is disposed over an opening of the cavity with the substrate oriented such that the MUT located within the cavity.

A speaker comprises a housing, a transducer residing inside the housing, and at least one sound guiding hole located on the housing. The transducer generates vibrations. The vibrations produce a sound wave inside the housing and cause a leaked sound wave spreading outside the housing from a portion of the housing. The at least one sound guiding hole guides the sound wave inside the housing through the at least one sound guiding hole to an outside of the housing. The guided sound wave interferes with the leaked sound wave in a target region. The interference at a specific frequency relates to a distance between the at least one sound guiding hole and the portion of the housing.

A speaker comprises a housing, a transducer residing inside the housing, and at least one sound guiding hole located on the housing. The transducer generates vibrations. The vibrations produce a sound wave inside the housing and cause a leaked sound wave spreading outside the housing from a portion of the housing. The at least one sound guiding hole guides the sound wave inside the housing through the at least one sound guiding hole to an outside of the housing. The guided sound wave interferes with the leaked sound wave in a target region. The interference at a specific frequency relates to a distance between the at least one sound guiding hole and the portion of the housing.

A speaker comprises a housing, a transducer residing inside the housing, and at least one sound guiding hole located on the housing. The transducer generates vibrations. The vibrations produce a sound wave inside the housing and cause a leaked sound wave spreading outside the housing from a portion of the housing. The at least one sound guiding hole guides the sound wave inside the housing through the at least one sound guiding hole to an outside of the housing. The guided sound wave interferes with the leaked sound wave in a target region. The interference at a specific frequency relates to a distance between the at least one sound guiding hole and the portion of the housing.