Abstract: In order to measure a scanning light cut-off region, an output of a light receiving element and a threshold value set by an MPU are compared by a comparator and a region where the former is smaller than the latter is measured as the scanning light cut-off region. During one cycle of optical scanning, this threshold value is switched in a plurality of stages according to the scanning angle. By accurately measuring the scanning light cut-off region, the correct position and size of an indicator such as a finger or pen are calculated.

Abstract: An ultrasonic printing method by which recording of a high resolution can be achieved. In the ultrasonic printing method, some or all of a plurality of ultrasonic oscillators are selectively driven in such phases that a difference in phase at a predetermined point between a reference ultrasonic wave from one of the selected ultrasonic oscillators and another ultrasonic wave from any other one of the selected ultrasonic oscillators is equal to or less than one-fourth a wavelength of the ultrasonic waves in a transmission medium for the ultrasonic waves from the selected ultrasonic waves to the predetermined point. The ultrasonic printing method can be applied to various printing apparatus for which recording of a high resolution is required.

Abstract: The ultrasonic coordinates input device includes receivers grouped into a plurality of groups, each receiver receiving the ultrasonic waves propagated through a propagator so as to calculate the coordinates of the ultrasonic wave inputted positions on the basis of signals received by each group, thereby ensuring that the coordinates are calculated with a simple mathematical formulae with a negligible error if any.

Abstract: There is provided an ultrasonic diagnostic apparatus in which a plurality of piezoelectric transducers are arranged in a predetermined direction so as to transmit and receive ultrasonic waves to obtain a tomographic image on the inside of the subject. The ultrasonic diagnostic apparatus adopts such a scheme that a sector scan is electronically performed, and is capable of preventing deterioration of an image by reducing an influence of reflection of the ultrasonic waves from the ribs, and forming a good image improved in resolution. An intersection of scan lines at at least receiving end is set up between rib-to-rib which are located at the position deeper than the body surface of the subject. An aperture for transmitting and receiving of ultrasonic waves along the scan line of the central part of the sector configuration is wider than that along the scan line of the edge portion of the sector configuration.

Abstract: An ultrasonic coordinate input, apparatus comprising a plurality of ultrasonic wave receivers to receive ultrasonic wave emitted by a cordless ultrasonic pen and propagating in an ultrasonic propagating medium, a plurality of receiving circuits for detecting the rising edges of received signals of the ultrasonic wave receivers, a measuring circuit for measuring the difference in time of receiving ultrasonic wave between the ultrasonic wave receivers and a calculating circuit for calculating the coordinates of ultrasonic wave input position according to the result of measurement. When the receiving circuits, the measuring circuit and the calculating circuit are installed together with the ultrasonic wave receivers on the ultrasonic propagating medium, the entire apparatus can be made small in size.

Abstract: There is provided an ultrasonic printer in which convergent ultrasounds are radiated to emit an ink near a convergent point of the convergent ultrasounds in the form of an ink droplet and deposit the ink droplet on a recording medium such as a paper sheet, thereby performing a recording on the recording medium with multiple ink dots, with higher resolution. The ultrasonic printer has a plurality of ultrasonic transducers which transmit phase-controlled ultrasonic waves to form an convergent ultrasonic acoustic beam.

Abstract: An acoustic imaging system includes pairs of variable gain amplifiers for deriving essentially pairs of signals from respective signals generated in respective ultrasonic vibrators and the pairs of signals are superimposed on each other in a time difference corresponding to a phase angle of .pi./2 in frequency of ultrasonic waves. Amplification factors of the variable gain amplifiers are controlled so that the desired phase shift of the superimposed signals is obtained to attain dynamic focusing. Another acoustic imaging system includes a switch circuit having a two stage matrix switches construction that performs matrix switch functions in a smaller number of switch elements. Still another acoustic imaging system includes constituents for the aforementioned phase control for fine adjustment of delay time, the aforementioned switch circuit for rough adjustment of delay time, and variable gain amplifiers that perform smooth switching of the delay time.

Abstract: An ultrasonic diagnostic apparatus including ultrasonic transducers. The ultrasonic diagnostic apparatus performs calculations for respective ultrasonic transducers to determine at which focal position a signal having just been received by the transducers is reflected in accordance with a lapse of time from a time when ultrasonic waves are transmitted. A delay time of respective received signals obtained from the transducers are determined in accordance with the results of the calculations. According to the present invention, control data which determines the delay time is stored in a first stored apparatus, compensation data which compensates the control data is stored in a second storage apparatus. The control data and compensation data read out respectively from these first and second storage apparatuses are added to one another, and the delay time for transmission and reception is determined according to the sum of the control data and compensation data.

Abstract: An ultrasonic imaging apparatus for obtaining a tomogram image of an object to be diagnosed on a monitor includes electroacoustic transducers, a phasing unit, a phase detection unit, and an adding unit. The electroacoustic transducers are positioned in aligned relationship along a surface of the object, emit ultrasonic waves which penetrate the object, detect the ultrasonic waves reflected from the object and convert the reflected and detected waves to electrical detection signals. A phasing unit is connected to the electroacoustic transducers and receives the detection signals, delays them in accordance with delay amounts previously set therein and determined in accordance with the respective distances between the electroacoustic transducers and the object, and phase adjusts same to produce phase-matched detection signals.

Abstract: An ultrasonic wave beam former including: a ultrasonic wave probe (1) equipped with a plurality of transducers (2) for converting a ultrasonic wave signal to an electric signal for effecting a dynamic focus by multiplying each channel signal as an output signal from each of the transducers (2) by a reference wave signal having the phase which is dynamically adjusted for each channel, and adding together each after-multiplication signal after the multiplication through a delay line (3), characterized in that at least two kinds of reference signals having mutually different frequencies are provided for each of the channels and at least two multipliers (10) are also provided;each of the reference signals is constituted so as to receive an ultrasonic wave signal from a direction differenct from others and have a phase angle (.theta.

Abstract: An ultrasonic imaging apparatus for obtaining a tomogram image of an object to be diagnosed on a monitor is provided. The apparatus includes electroacoustic transducers, a phasing unit, a phase detection unit, a reference signal generating unit, and an adding unit. Electroacoustic transducers are provided in a lie along a surface of the object, emit ultrasonic waves to the object, detect the ultrasonic waves reflected therefrom, and convert them to electric signals as detection signals; a phasing unit is operatively connected to the electroacoustic transducers for receiving the detection signals, delaying them in accordance with distance between the electroacoustic transducers and the object, and phasing them to match the phase of detection signals.

Abstract: A plurality of rectangular piezo-electric ultrasonic sector transducers are aligned to form an array, and each transducer has first and second electrodes on its radiating surface. The first electrode is located on a center line of the sector transducer's length, and has a first length in the longitudinal direction and a first width along the center line. Two of the second electrodes are arranged outside the first electrode, symmetrical to the center line. The two second electrodes have a second length in the longitudinal direction longer than the first length, and have a second width which is almost the same as the first width, along a line near the center line. Thus, diamond-shaped electrodes excellent for providing a beam narrow in the longitudinal direction can be employed as the first electrode, and the combination of the first and second electrodes can be connected to each other.

Abstract: An ultrasound probe for a medical imaging system, comprising an ultrasound absorber and a piezoelectric vibrator mounted on the ultrasound absorber, cut in the direction from the surface of the piezoelectric vibrator to the ultrasound absorber into an array by a plurality of cutting grooves. The cutting depth d of each cutting groove in the ultrasound absorber is determined as an integer multiple of a quarter of a wave length .lambda. corresponding to a center frequency f.sub.0 of ultrasound waves radiated from the piezoelectric vibrator. Consequently, symmetrical electro-acoustic conversion characteristics of the ultrasound probe can be obtained in the frequency domain.

Abstract: Ultrasonic transducer having a plurality of piezoelectric elements arranged in a matrix, and a method for fabricating them. L shaped printed wiring boards are respectively bonded to each arrays of piezoelectric elements arranged in azimuthal direction. The bonding points of the L shaped printed wiring board to respective piezoelectric element are located at edge portion of respective back electrode. The other branch of L shaped printed wiring boards are stretched vertically to the surface of the piezoelectric elements matrix. A backing plate is formed by molding on the back side of the piezoelectric elements matrix leaving the top of the L shaped printed wiring board protruded from the molded surface of the molded backing plate. Such configuration prevents the reflection from the wiring plate of the piezoelectric element. A flexible printed wiring board is provided with wiring pattern having bonding areas positioned corresponding to the matrix of piezoelectric elements.

Abstract: An ultrasonic sector-scan probe comprises at least an array having a plurality of ultrasonic transducer segments, a window for transmitting and receiving ultrasonic waves and an ultrasonic wave propagation medium filled in a front space between the array and the window. A group of the ultrasonic transducer segments are selectively driven as an aperture and ultrasonic waves emitted therefrom are converged into a beam for transmission and reception. By partly or entirely changing the segments in the group with the ones outside the group the scan line is shifted to a new angle, and a member under test contacted with the window on the outside thereof is sector-scanned by the ultrasonic beam. The array is arranged so that scanning lines of the groups intersect at one point in the window or in its vicinity for sector scan.

Abstract: An ultrasonic sector-scan probe comprises at least an array having a plurality of ultrasonic transducer segments, a window for transmitting and receiving ultrasonic waves and an ultrasonic wave propagation medium filled in a front space between the array and the window. A group of the ultrasonic transducer segments are selectively driven as an aperture and ultrasonic waves emitted therefrom are converged into a beam for transmission and reception. By partly or entirely changing the segments in the group with the ones outside the group the scan line is shifted to a new angle, and a member under test contacted with the window on the outside thereof is sector-scanned by the ultrasonic beam. The array is arranged so that scanning lines of the groups intersect at one point in the window or in its vicinity for sector scan.

Abstract: An ultrasonic diagnostic apparatus protected from multi-reflection of sound echoes. Multi-reflection is avoided by eliminating the reflection from the surface of an electro-sound transducer. This invention eliminates the surface reflection of the transducer by following three methods:(a) changing a direction of each surface of an array of transducer elements to direct the reflected sound wave away from the main direction of the sound beam;(b) applying an acoustic matching layer to a surface of a piezo-electric device of the transducer to cancel out phases of sound waves reflected by the surfaces of the layer and the device; and(c) providing an acoustic matching surface on a front or back face of the piezo-electric device to cancel out phases of sound waves reflected by the surface of the device.

Abstract: An ultrasonic imaging apparatus comprises transducers for transmitting ultrasonic waves and receiving acoustic. The apparatus also transmits ultrasonic waves of different frequencies simultaneously from a plurality of transducers.The frequency characteristics of the transducers are determined in a manner so as to produce the function of frequency filters. An electric filter is additionally provided for compensation. Thus, crosstalk is eliminated even when the frequency difference between the transmitting ultrasonic waves is kept small.