Abstract: The ear speaker device includes a mount section that is provided with ear-hook sections, and rotation sections that rotate speaker movable sections with respect to the mount section. Tubular ducts are positioned more inside than the ear-hook sections in a natural state. When the ear speaker device is mounted, the speaker movable sections are rotated to the most outside positions. Then, the ear-hook sections are brought into contact with auricle base upper sections, respectively, and the speaker movable sections are rotated inwardly. In this manner, the tubular ducts can be positioned in the vicinity of the external acoustic meatus openings, respectively, of the listener without interfering with auricles and the like.

Abstract: The ear speaker device includes a mount section that is provided with ear-hook sections, and rotation sections that rotate speaker movable sections with respect to the mount section. Tubular ducts are positioned more inside than the ear-hook sections in a natural state. When the ear speaker device is mounted, the speaker movable sections are rotated to the most outside positions. Then, the ear-hook sections are brought into contact with auricle base upper sections, respectively, and the speaker movable sections are rotated inwardly. In this manner, the tubular ducts can be positioned in the vicinity of the external acoustic meatus openings, respectively, of the listener without interfering with auricles and the like.

Abstract: An ear speaker device includes an electroacoustic transducer including a housing mounted at a predetermined position of listener's head, a speaker unit mounted on one surface in the housing, and positioned away from an entrance of the listener's external acoustic meatus for a predetermined distance when the housing is mounted on the listener's head, and a tubular duct extended so as to allow a sound generated by the housing in the inner space thereof to reach the vicinity of the entrance of the listener's external acoustic meatus, and a hole for emitting sound of the duct is oriented to the opposite direction with respect to the entrance of the external acoustic meatus; and a mounting part used for mounting the electroacoustic transducer on the listener's head in a manner that the predetermined distance is provided between the speaker unit and the entrance of the listener's external acoustic meatus.

Abstract: An ear speaker device includes an electroacoustic transducer including a housing mounted at a predetermined position of listener's head, a speaker unit mounted on one surface in the housing, and positioned away from an entrance of the listener's external acoustic meatus for a predetermined distance when the housing is mounted on the listener's head, and a tubular duct extended so as to allow a sound generated by the housing in the inner space thereof to reach the vicinity of the entrance of the listener's external acoustic meatus, and a hole for emitting sound of the duct is oriented to the opposite direction with respect to the entrance of the external acoustic meatus; and a mounting part used for mounting the electroacoustic transducer on the listener's head in a manner that the predetermined distance is provided between the speaker unit and the entrance of the listener's external acoustic meatus.

Abstract: An ear speaker device includes an electroacoustic transducer including a housing mounted at a predetermined position of listener's head, a speaker unit mounted on one surface in the housing, and positioned away from an entrance of the listener's external acoustic meatus for a predetermined distance when the housing is mounted on the listener's head, and a tubular duct extended so as to allow a sound generated by the housing in the inner space thereof to reach the vicinity of the entrance of the listener's external acoustic meatus, and a hole for emitting sound of the duct is oriented to the opposite direction with respect to the entrance of the external acoustic meatus; and a mounting part used for mounting the electroacoustic transducer on the listener's head in a manner that the predetermined distance is provided between the speaker unit and the entrance of the listener's external acoustic meatus.

Abstract: First to fourth lenses are aligned in an optical axis direction by a lens-barrel of a camera, an O-ring is disposed between the first lens and the lens-barrel, an O-ring is disposed between the fourth lens and the lens-barrel, a space is formed between the first and second lenses, a space is formed between the second and fourth lenses, a space is formed between the third and fourth lenses, and flow of air between the spaces is precluded. The camera thus configured is free of dewing on the lens or a protective plate exposed to the exterior, even when the inside temperature is raised due to heat generation in a CCD or a mounting substrate on which the CCD is mounted.

Abstract: The ear speaker device includes a mount section that is provided with ear-hook sections, and rotation sections that rotate speaker movable sections with respect to the mount section. Tubular ducts are positioned more inside than the ear-hook sections in a natural state. When the ear speaker device is mounted, the speaker movable sections are rotated to the most outside positions. Then, the ear-hook sections are brought into contact with auricle base upper sections, respectively, and the speaker movable sections are rotated inwardly. In this manner, the tubular ducts can be positioned in the vicinity of the external acoustic meatus openings, respectively, of the listener without interfering with auricles and the like.

Abstract: An ear speaker device includes an electroacoustic transducer including a housing mounted at a predetermined position of listener's head, a speaker unit mounted on one surface in the housing, and positioned away from an entrance of the listener's external acoustic meatus for a predetermined distance when the housing is mounted on the listener's head, and a tubular duct extended so as to allow a sound generated by the housing in the inner space thereof to reach the vicinity of the entrance of the listener's external acoustic meatus, and a hole for emitting sound of the duct is oriented to the opposite direction with respect to the entrance of the external acoustic meatus; and a mounting part used for mounting the electroacoustic transducer on the listener's head in a manner that the predetermined distance is provided between the speaker unit and the entrance of the listener's external acoustic meatus.

Abstract: First to fourth lenses are aligned in an optical axis direction by a lens-barrel of a camera, an O-ring is disposed between the first lens and the lens-barrel, an O-ring is disposed between the fourth lens and the lens-barrel, a space is formed between the first and second lenses, a space is formed between the second and fourth lenses, a space is formed between the third and fourth lenses, and flow of air between the spaces is precluded. The camera thus configured is free of dewing on the lens or a protective plate exposed to the exterior, even when the inside temperature is raised due to heat generation in a CCD or a mounting substrate on which the CCD is mounted.

Abstract: An infrared-ray cordless microphone including a modulator for modulating an acoustic-to-electric converted sound signal through a predetermined process; and an infrared-ray transmitter for transmitting an output infrared signal obtained by converting the modulated sound signal from the modulator; wherein the infrared-ray transmitter is disposed at a lower end of the microphone body. There is also provided an infrared-ray cordless microphone system comprising such a microphone and a sound output means which includes an infrared-ray receiver for receiving the infrared signal from the microphone, a demodulator for demodulating the received infrared signal, and an electric-to-acoustic converter for converting the demodulated signal into a sound signal.

Abstract: An optical reception apparatus comprises of a prism made by forming in a member of substantially the frustum of a circular cone made of a transparent material a concave portion of a substantially circular cone or substantially the frustum of circular cone whose diameter is gradually reduced in the direction from a small diameter circular outer side surface to a large diameter circular outer side surface of the frustum of the circular cone, and a light receiving element mounted on the prism at its position along a center line of a circle of the large diameter circular outer side surface and also in the vicinity of the large diameter circular outer side surface.