Abstract: Response-modifying acoustic couplers are provided for use between an output port of a hearing aid unit and an earmold at the entrance to the ear of a wearer, including a passage and a chamber which respectively provide a high acoustic inertance and a high acoustic compliance to cooperate with other acoustic elements and to form an acoustic network producing a predetermined frequency response characteristic.

Abstract: A silent audio switch provides switching between multiple audio sources while eliminating the "pop" caused by switching spikes. Two internal buses are used for each visible external bus, whereby a new audio signal is first switched to an off-air bus opposite an on-air bus, any switching spike is allowed to subside, and then a fast mix is made between the two buses to derive the new audio signal as the switch output signal.

Abstract: An electro-vibration transducer for converting sound signals into body-sensible acoustic vibrations to permit the listener to sense sound directly through his or her body and having a wide effective bandwidth and good transient response characteristic. An auxiliary vibrator, namely, a weight, is attached to a magnetic circuit of the transducer via an elastic member. The auxiliary vibrator can be attached to an outer annular surface of the magnetic circuit, or to a lower planar surface thereof. Preferably, the elastic member is made of a visco-elastic material.

Abstract: The present invention provides a completely self-contained intraoral larynx comprising a power source, tongue activated controls, power saving signal generation circuitry, acoustic and audio amplifiers, and an intra-oral speaker. These components are contained within an otherwise conventional denture or dental prosthesis. The device produces a high amplitude sound while minimizing current drain from the power source. Laryngectomized patients require only short term training by a speech pathologist to use this device. Intelligible speech is usual within an hour of such training, and facility rapidly improves. The psychological barriers, post-operative physical limitations, aesthetic concerns and limited gestural communication traditionally associated with the use of extra-oral larynges is eliminated by the present invention.

Abstract: The housing is essentially spherically shaped, formed with a flattened end wall (14), through which a sound receiving opening (42) extends in axial direction, located eccentrically with respect to the spherical housing. A volume control button (50) covers the sound receiving opening, the volume control button being maintained by a small distance (h) spaced from the spherical end wall to permit entry of sound to the sound receiving opening, while preventing masking of the sound receiving opening by the finger of a user, and free entry of contamination thereto. Preferably, the button is connected to the volume control element by an inwardly extending collar (52) which snaps over an adjustment rim (35) on a volume control positioned axially centrally on a printed circuit board (31) secured within the housing and passing through a central opening (47) formed therein.

Abstract: An apparatus and method for the automatic focussing of a video camera having a camera circuit for generating electric image signals corresponding to the brightness of an object, a circuit for sampling at least two sampling signals from the electric image signal, an A/D converter for obtaining at least one inclination value corresponding to at least one pair of the sampling signal, and a stop for stopping a focussing lens when at least one of the inclination values exceeds a predetermined value.

Abstract: Sound in ducts can be reduced by using two cancelling sources spaced along the duct, and in order to reduce reflections upstream of the cancelling sources, sounds from these sources may be arranged to be in phase opposition upstream from the sources at all frequencies. Such an arrangement does not provide cancellation downstream at some frequencies. In the invention sound detected by a microphone is processed to generate a drive signal for a first source which tends to cancel sound in the duct partially, the remainder of the cancellation being provided by a sound source. A delay positioned between the sources is such that sounds from these sources are in phase at all frequencies of interest downstream of the second source.

Abstract: Acoustic attenuation apparatus (2) is provided for a duct (4) guiding an acoustic wave propagating (6) therethrough. A silencer (8) is provided for passively attenuating the acoustic wave in the duct, and a cancelling speaker (32) is provided within the silencer. The combination provides hybrid active/passive combined attenuation. Various rectangular and circular structures are disclosed, together with multi-path and multi-speaker arrangements.

Abstract: A sound production device has at least one generator for producing a video signal and an analog-to-digital converter if the video signal is not already digital. The video is converted to a plurality p of signals which are representative of P parameters. The device also has a set of digital-to-analog converters equal in number to the number of parameters and a matrix for connecting the P signals to a second plurality of q inputs of a sound synthesizer, the output of which is connected to a loudspeaker.

Abstract: An adaptive noise suppressor for providing noise filtered signals. The noise suppression device employs a vector gain .mu. for the weights of the filter wherein the vector .mu. is selected for each frequency bin to be inversely proportional to the power spectrum. A projection operator is utilized to remove the effects of circular convolution to produce a linear convolution result wherein the weights are readjusted in a manner to minimize the difference between the input signal and the filter output signal, thereby minimizing the error signal to produce a noise suppressed signal in the filtered output. A frequency suppression device utilizes the same principles of the vector .mu. and projection operator, but the output is taken from the error output of the filter.

Abstract: A microphone and loudspeaker arrangement for use in a teleconference system, wherein a plurality of microphones are held in a fixed relationship to a loudspeaker. The microphones are independently gated ON in response to (1) speech picked up by the microphone, (2) a loudspeaker signal driving the loudspeaker and (3) an electrical signal related to the microphone signals of the other associated microphones. A noise adapting threshold circuit generates a voltage level representative of background noise which is compared with the microphone signal of a respective microphone for determining whether the microphone is receiving speech. A decisional circuitry monitors the microphone signal of the associated microphone with respect to a MAX bus which carries microphone signals representative of the level of microphone signals at the other microphones. The decisional circuitry generates a signal indicating that the associated microphone is the first loudest microphone signal.

Abstract: The present invention relates to an improved directional microphone system which utilizes at least two directional microphones. The microphones included in the system are connected to an electrical circuit which is programmed to cancel static noise and to facilitate dynamic gain control. The received signals from the two microphones are fed into a microcomputer where a fast Fourier transformation is made on the two signals in order to go from the time domain to the frequency domain. A lowpass and highpass filtering technique is used to cancel the dynamic noise. The frequency components of the incoming signals are further used to utilize an area and phase sorting technique to allow only the pickup of the wanted sound in a well-defined area. An inverse fast Fourier transformation is made and the modified signal is outputted in the time domain. Sounds generated from outside the work area are essentially cancelled out by a combination of the directionality of the microphones and the sorting techniques employed.

Abstract: An automatic focusing device for a video camera in which undesirable defocusing caused by the presence of an unwanted object moving through the field of view between the photographing lens and the desired object is eliminated. The output of automatic focusing sensor, which may be a line sensor or area sensor, is alternately stored in two memories. The contents of the two memories are compared and discriminated to determine when an unwanted object has moved into the photographing field. This is effected by detecting the presence of a change beginning at one end of the sensor. When such is detected, the automatic focusing operation is inhibited for a predetermined period of time.

Abstract: In a rotary head magnetic recording and reproducing system of a helical-scan type for successively recording and reproducing audio signals in and from record patterns on a magnetic tape, which record patterns are inclined relative to the longitudinal direction of the magnetic tape, by a magnetic head provided on a rotary cylinder, during the successive reproduction of the record patterns by the magnetic head, in order to prevent noise from being contained in a reproduced audio signal, which noise is caused by the switching of the record patterns to be reproduced or by the occurrence of a dropout in the reproduced signal, an audio signal is divided into two discrete signals which have a phase difference therebetween and are transmitted respectively on two separate transmission paths, and two hold circuits, each of which is arranged in one of the two transmission paths, are put into operation in synchronism with the switching of the record patterns or the occurrence of the dropout in the reproduced signal, and

Abstract: A sound field correcting device for use in a stereophonic system intended for vehicular use. Speakers are installed on opposite sides of both the front and rear seats of the vehicle. The number of persons seated in the vehicle is determined and applied to a correcting unit. When plural persons are seated in the vehicle, the sound pressure levels in the high-frequency range of loudspeakers is increased. Also, the sound pressure levels of the speakers can be corrected in accordance with the positions at which persons are seated in the vehicle.

Abstract: An image sensing apparatus comprises: a photo detecting unit for converting an optical image to electrical information; and unnecessary charge transfer unit, formed in a peripheral portion of the photo detecting unit, for transferring the unnecessary charges; a charge removing unit provided at the final end of the unnecessary charge transfer unit; and a drive circuit for driving the unnecessary charge transfer unit synchronously with the transfer of the whole electrical information in the photo detecting unit.

Abstract: Audio equipment designed for use at widely varying ambient noise levels allows an audio signal to be amplified to enhanced levels under noisy conditions without added distortion near the high-amplitude end of its dynamic range. Detected or anticipated ambient noise conditions trigger a dynamic range controller to boost the gain of the audio signal to an extent inversely related to the audio signal amplitude. Thus, low-volume audio will be boosted to a great extent while the high-volume end of the dynamic range will experience little or no additional gain. The net effect is two allowable dynamic ranges, both sharing the same high-end volume level but with possibly widely different low-end volume levels. This gain and dynamic range control may also be performed independently on a number of discrete frequency bands. In addition, noise components inherent to the audio signal may be filtered to ambient noise-dependent extends, or the gain boost may be inhibited at volume levels susceptible to such noise.

Abstract: A multiple band automatic gain control circuit having a band splitter which is responsive to an input audio signal for separating the audio signal into plural components of different frequencies. Plural gain adjustment circuits each control the gain of an associated one of the components, wherein each of the gain adjustment circuits includes a voltage controlled amplifier, and feed forward control elements for controlling the voltage controlled amplifier as a function of the amplitude of the associated component. A signal combiner combines the gain adjusted components to thereby form a gain adjusted audio signal. A limiter circuit prevents the combined signal from exceeding predetermined amplitude constraints by simultaneously reducing the gain of all of the variable gain circuits whenever the combined signals exceed the predetermined constraints.

Abstract: A body-sensible acoustic device which can be readily mounted on and detached from a seat of an automobile. A drive unit driven by acousto-electrical signals is mounted on a vibration transmitting member. A pair of clamping members are provided which are coupled to the vibration transmitting member in such a manner as to be slidable with respect thereto and swingable in a plane including the vibration transmitting member. Each clamping member has an arm for a holding a side frame provided in the seat body.

Abstract: A solid-state image pickup device has photo-sensitive picture elements arranged in a matrix to convert light containing picture element information into electrical charges. A horizontal charge transfer element and a vertical charge transfer element respectively transfer electrical charges corresponding to individual picture elements in a horizontal and vertical direction. At least one of the vertical charge transfer elements and horizontal charge transfer elements is controlled in response to external control signals so that a part of the electrical charges corresponding to individual picture elements in a specified part of the photosensitive picture elements are outputted as picture element output signals.