Abstract: An intraoral dental imaging system employs a service unit having a power supply and a light source, and selectively using a video camera having a plug-in module for releasably connecting the video camera to the power supply, or an x-ray camera having a second plug-in module for releasably connecting the x-ray camera to the power supply. In either case the modules have processing means for producing video output signals. These video output signals may be sent to a wide variety of devices connected to the service unit. For instance, they may be used to display an image on a video monitor, such as a CRT, they may be sent to a printer for printing, and they may be sent to a modem for eventual display at another location. In essence, these video output signals may be sent to any device known in the art. Thus, the plug-in modules are highly portable while allowing for interchangeability within the same service unit, thereby allowing a practitioner to use the modules in multiple operatories.

Abstract: An x-ray or gamma ray image that is produced as an array of pixels is treated for reduction or elimination of white spot noise. Two or more successive images in registry are produced and the pixel values at each pixel location are inspected for the respective images. The pixel values are considered according to rank, e.g. from dark to bright, and the lowest ranking pixel value is selected for each pixel location. This creates an output image that is substantially free of the spot noise that results from direct impingement of the x-ray photons on the imaging device. This technique is especially useful in portal imaging for radiation therapy, dental imaging, or industrial imaging.

Abstract: A charge injection imaging device comprises low bandwidth, low noise performance column amplifiers serially connected to respective charge coupled device storage lines. Image and/or noise defining electronic information signals are retrieved from the charge injection imaging device by way of the amplifiers and storage lines in a manner which provides image defining electronic information signals from which the noise defining electronic information signal portions have been automatically subtracted for each succeeding photosensitive element of the device. The subtracted noise portions include both KTC noise and fixed pattern noise which are normally inherently associated with the image defining electronic information signals retrieved from the charge injection imaging device.

Abstract: A method for generating an output stream of digital data words, with each data word representing the amplitude of an analog signal at one of a multiplicity F samples each second and with substantially equally spaced time intervals T therebetween, is obtained from a digital baseband demodulation system used for array beam forming. A data stream, formed of interleaved ADC output digital data words acquired from a set of converters, is at a rate of F total samples/second. Subsequent digital demodulation, filtration, and decimation provides digital output signals which need less delay resolution prior to the formation of coherent sum signals, thereby reducing overall channel memory requirements. The output baseband data stream has enhanced dynamic range, thereby reducing the ADC bit density requirements.

Abstract: An ultrasonic imaging processing system includes transducers and means to generate in an analog fashion, in-phase and quadrature phase signals. These signals are converted to digital form and a butterfly phase rotator circuit is employed to correct for phase differences in beam steering and focusing. In particular, speed and simplicity is achieved through the utilization of read only memory means providing appropriate function values for phase correction in conjunction with digital multiplication and summing circuitry.

Abstract: A charge-injection-device imager, having reduced crosstalk in a two-dimensional array of pixels each of which stores charge responsive to impingent light photons and until injection occurs, has: a column scanner for cyclically scanning each successive column of the array for each row to be scanned; a row scanner for cyclically scanning each successive row of the array, with each row being enabled after the conclusion of an injection time interval which appears after a previous row has been scanned, and also for re-scanning that row again while a second-next row is being scanned; line delay storage for the video signal provided by two successively scanned rows; and a subtractor for providing an imager output signal as the difference between the stored video signal from any row and the video signal from that same row after the stored charge of that row of pixels has been injected out of that row of pixels only after the next row had already been readout.

Abstract: Multispectral imaging apparatus for producing a composite visible/infrared image includes a wavelength-independent focus reflective optical system for focusing visible and infrared radiation from a scene onto a hybrid visible/infrared radiation detector. The detector comprises an array of visible radiation responsive elements interspersed with infrared radiation responsive elements and provides first and second output signals corresponding, respectively, to the visible and the infrared radiation impinging upon the detector. The first and second signals are converted to a visible black and white image of the scene and a step-tone false color infrared image of the scene. The images are combined in exact spatial registration to produce a composite image comprising a visible image of the scene which is highlighted by the infrared radiation emitted by the scene.

Abstract: A capacitor structure which is particularly suitable for use in analog integrated circuit devices employs an intermediate layer of a refractory metal disposed in a thin layer overlying a flat dielectric surface. The thinness and the low reflectivity of the refractory metal facilitates precise patterning of the upper plate of the capacitor structure. In the present invention, capacitance is no longer determined by imprecise cuts through thick oxide layers or by patterning of thick metallization layers within these apertures. The use of refractory metals in the capacitor structure also readily permits the incorporation of resistive circuit elements.

Abstract: Programmable signal processing apparatus for multiplying a sampled analog signal by a multiple bit digital word coefficient. All signal processing operations are accomplished by the splitting, routing and combining of charge packets formed in a charge domain device.

Abstract: Programmable signal processing apparatus for multiplying a sampled analog signal by a multiple bit digital word coefficient. All signal processing operations are accomplished by the splitting, routing and combining of charge packets formed in a charge domain device.

Abstract: The signal processing apparatus includes a plurality of multiplying or charge splitting stages connected in series. A plurality of pairs of control words are provided, one word of each pair being the complement of the other word of the pair. Each pair of words is associated with a respective multiplying stage and represents the multiplying coefficient of a respective multiplying stage. Means are provided for forming a plurality of quantities of charge, each representing a respective sample of an analog signal. Each of the quantities of charge is introduced in sequence into each of the multiplying stages in which it is processed and then passed on to the next multiplying stage. The process operation in each of the multiplying stages includes dividing the quantity of charge in a series of splitting operations under the control of the pair of words associated with the stage into two parts. All of the first parts of each of the quantities of charge in each of the stages is summed.

Abstract: A charge transfer filter utilizing a charge transfer accumulator structure for exponential smoothing of sampled data signals is described. The charge transfer accumulator structure performs charge equilibration at high speed thereby enabling an exponential decay impulse response to be obtained at high speed.

Abstract: A filter utilizing charge transfer devices for providing recursive transfer functions is described. The filter includes a circular charge transfer shift register having an even number N of stages, greater than two, a first charge transfer shift register, and a second charge transfer shift register. A first input stage is unidirectionally coupled to the first stage of the first shift register and is also bidirectionally coupled to the N.sup.th stage of the circular shift register. A second input stage is unidirectionally coupled to the first stage of the second shift register and is also bidirectionally coupled to the (N/2).sup.th stage of the circular shift register. A first input sequence of packets of charge representing positive weight components of a signal is applied to the first input stage and a second input sequence of packets of charge representing negative weight components of the signal is applied to the second input stage. All three shift registers are clocked at the same frequency.

Abstract: A charge transfer filter utilizing a charge transfer accumulator structure for exponential smoothing of sampled data signals is described. The charge transfer accumulator structure performs charge equilibration at high speed thereby enabling an exponential decay impulse response to be obtained at high speed.