Abstract: Disclosed herein is a phantom for calibrating dual energy x-ray equipment for body fat measurements. In particular, the present invention provides a limited number of calibrated plates of materials simulating different body fat percentages. By combining the plates, a range of simulated body fat compositions may be precisely obtained. The plates may be of arbitrary size to provide a simulation over a broad area and may include a high density end cap for triggering an automatic region of interest detection for certain scanner systems.

Abstract: Disclosed herein is a spine phantom for calibrating a dual energy x-ray attenuation measurement device for measuring vertebral bone density. Simplified construction of the phantom is made possible by equating the density variations in the three dimensionally complex and inhomogeneous spine as a set of easily machined flat surfaces of different thicknesses. In particular, the spine phantom includes a vertebra-simulating body having a base surface perpendicular to the x-ray beam of the measurement device and defining an intervertebral section, a composite bone section and cortical wall sections. These sections each extend to planes of different heights from the base surface, so as to simulate cartilage, cortical and tabecular bone, and cortical bone wall regions of a human spine, respectively. The spine phantom of the present invention can include multiple vertebra-simulating bodies simulating a range of vertebra types and densities.

Abstract: A projectional densitometry system performs a scan of an individual's left and right femora by using the location of one femur to estimate a starting location for scanning the opposite femur. The estimated starting location of the second femur scan is based on metric data inputted by the operator or extracted from the first femur scan. Alternatively, the densitometry system performs an initial bone-locating scan of both femora, after which it performs a second, density-measuring scan based on the metric data extracted from the initial scan. A special leg positioning device is used to properly orient both femora for scanning, obviating the need to reposition the individual after scanning the first femur.

Abstract: A raster display digital oscilloscope includes an analog to digital converter and a memory array for developing and storing a digital measurement signal amplitude-dependent on an acquired input signal. After processing stored digital signals are conveyed to an output circuit which includes a raster-scanned CRT and three display memory planes independently addressable by the CPU for receiving in discrete address locations the digital data. Corresponding address locations in the three planes are read in synchronism with the CRT scan to develop a display signal for application to the CRT to produce a display corresponding to the sum of the data stored in the three planes. The digital signals are automatically spread out or bunched up within the display planes to compensate for differences between the data acquisition rate and the scan rate.

Abstract: A digital waveform measuring and display oscilloscope includes a digital memory which stores one full screen of waveform data. The analog waveform is sampled, digitized and placed in memory at a user selected mode and sampling rate. A data acquisition mode control permits the user to select a continuous mode in which a live waveform is displayed moving from the right to the left on the screen. A hold mode is provided in which a preceding full screen data array is captured in the memory and displayed as a static display. A trigger mode is also provided with a variable delay, related to multiples of a full screen array, in which one full screen array is captured in relation to a trigger event and displayed as a static display. A particularly unique Periodic Hold mode creates a cyclical sequence which includes data acquisition and simultaneous display blanking which is terminated in response to a trigger signal sequence.

Abstract: A waveform measuring and analyzing instrument includes a pair of plug-in receptacles adapted to receive signal acquisition and/or processing plug-in units. Each of the receptacles is wired to a waveform data memory and to a programmed processor. The program memory for the processor includes addresses assigned to the plug-in units for addressing a memory in the plug-in units which include plug-in type and status data and may include a plug-in resident programmed memory array in which a data calculation program is stored. The processor is connected to execute the software program in the plug-in unit. The plug-in resident calculating capability significantly expands the power and capability of the instrument to analyze and process particular waveform signals. The software programmed plug-in units may be formed with a pre-programmed, read-only memory or may employ a read-write memory with means for interfacing to a still larger external storage or memory.