Helena Laboratories Corporation

Gene A Butts

Tipton L Golias

Henry A Garsee

Charles D Kelley

Bruce R Petty

James L Pauley

Samuel Rhine

Robert A Swift

A computer controlled diagnostic densitometer for analyzing optical density patterns of blood samples or the like scans a sample and generates an analog waveform signal representative of the scanned optical density pattern. The analog signal is amplified, digitized, stored in a memory and is later read from memory to reconstruct a visual display of the waveform for analysis. Several types of optical density pattens may be scanned which result in analog signals of different amplitudes and signal-to-background noise ratios. An improved amplification system automatically preadjusts the gain and reference value of the analog signal prior to digitization in order to substantially eliminate background noise in the signal and produce substantially full scale analog signal values. The gain and reference value preadjustments are performed by a pair of corresponding multipliers which multiply the analog signal by memory-stored digital data which is unique to the type of optical density pattern being scanned. The gain and reference voltage may also be manually preadjusted in order to assure sample-to-sample analysis consistency for samples from the same patient.

Densitometer with automatic gain and reference value adjustment of

A method of optically scanning a plurality of optical density patterns, such as blood samples or the like is provided wherein the samples are arranged in rows and each include a plurality of optical density segments extending along a first axis, and wherein the segments generally form columns of like segments along a second axis. The optical densities of a row of segments are first scanned along the first axis, following which the centerlines of each segment in the scanned row is determined along the first axis. Then, the segments of each column are scanned along the corresponding, previously determined centerline. The centerline of each segment is determined by displacing a scanning head relative to the sample along the first axis, measuring the optical density of each segment and correlating the magnitude of the measured optical density with the relative displacement between the head and the samples. The scanning of the segments along the centerlines is performed by displacing the scanning head relative to the samples along the second axis, measuring the optical density of each segment in the column being scanned and correlating the magnitude of the measured optical density with the relative displacement of the head and the samples. Voltages are generated which are proportional to the relative displacement between the head and samples along the first and second axes, and these voltages are converted to digital data and stored in memory for later use in the correlation process. A method is also provided for determining the location of each segment in an optical density pattern and for determining the length of the pattern.

Method of scanning optical density patterns

An optical system is disclosed for a densitometer which scans an electrophoretically separated sample and provides an output signal for graphical display indicative of the optical density of the scanned sample. The optical system provides storage for a plurality of filter assemblies selectively used depending on the mode of densitometry scanning. It includes a turret assembly, a detector housing, and a lamp support to permit an operator convenient selection capability of a desired filter when scanning in either visible or fluorescent modes of operation. A plurality of optical density and blocking filters are sandwiched between turret plates at spaced radial positions. The plates have aligned openings adjacent to the filter areas to permit light to pass through the filters for detection. Turret barrels and slit assemblies are mounted on one of the plates above the filters to protect the photo-responsive detector from stray light which may be present and to optimize the sensitivity and resolution of the electrophoresis patterns. The plate-filter sandwich unit is rotatably mounted above the detector such that the individual filters are selectively rotated into a position directly above and in alignment with the detector. The turret assembly includes an indexing mechanism and control arrangement to insure that only the visible light source is on when certain filters are above the detector and only the ultra-violet light source is on when other filters are above the detector. A sight alignment and override feature is provided in the optical system such that when the door to the densitometer is open, both the visible and fluorescent light sources are on. Under these conditions, light sources assist the operator in aligning the sample for scanning. Another part of the invention resides in the collimating slit assemblies mounted on the turret assembly which are used for defining the amount of light and the area of the sample seen by the detector in the fluorescent mode.

Optical system for densitometer

A microprocessor-controlled densitometer system for optically scanning a blood sample or the like and generating an electric analog signal which is a function of the optical density of the scanned sample. The electrical analog signal is processed and converted into digital data for storage in a memory as raw sample data to be retained until the next given sample is scanned. Under microprocessor control, a CRT device displays a re-constructed optical density analog waveform pattern representative of the generated electrical analog signal and may be normalized for full-scale readings. While the optical density analog waveform pattern is displayed on the CRT device, the operator may visually inspect and edit the analog waveform pattern by manually positioning a cursor signal along the CRT displayed analog waveform pattern for addressing selected positions thereon and modify the analog waveform pattern by keyboard entries which add, delete, or modify fraction boundary locations, delete portions of the analog waveform pattern from computations, etc., via keyboard entries and under microprocessor control. Once the operator is satisfied with the edited analog waveform pattern and the various fraction boundaries displayed on the CRT device, a keyboard command to the microprocessor enables the displayed and edited optical density waveform pattern or any integral or selected portion thereof to be graphically recorded as an analog profile trace on a fixed record medium and may, under microprocessor control, cause a printer to print fraction identifying information and numerical data such as ratios or percentages involving the area under the analog waveform pattern or particular fractions thereof, amplitude ratios, or scaled values calculated by the microprocessor onto the record medium and preferably in a position proximate to the fraction or portion of the profile traced to which such data pertains. The method and apparatus of the present system enables the displaying and editing of the analog waveform pattern, the calculation of desired numerical data, the recording of the profile trace and the printing of the calculated data without requiring that the sample be scanned a second time and without disturbing the digital data stored in the memory which represents the originally generated electrical analog waveform since the reconstruction of the display, the editing, and the numerical calculations are done under microprocessor control using only stored data and operator-entered keyboard commands.

Single scan microprocessor-controlled densitometer

An improved method for graphically displaying optical density patterns generated by a densitometer which scans a sample to generate analog signals indicative of the optical density of the sample. The maximum amplitude and cumulative amplitude of the analog signals are computed and stored simultaneously as normalizing signals. The sample is again scanned to recreate the analog signals which are directed in two paths toward two graphic display units. The recreated analog signals directed toward the first display unit are modified by the normalizing amplitude signal to create a visual display curve of the normalized density. The recreated analog signals directed toward the second display unit are modified by the normalizing cumulative amplitude signal to create a visual display of the normalized area under the density curve. The apparatus includes a scanning system having circuitry to provide analog signals indicative of the optical density of the sample and a pair of conventional graphic display devices. The analog signals are generated during a first scan of the sample and the maximum value is measured and stored in a digital-to-analog converter circuit while the cumulative value is simultaneously measured and stored in a voltage controlled digital-to-analog converter circuit. Each stored value is referred to as a normalizing signal. The sample is again scanned to regenerate the analog signals which are fed along two paths, one to drive each display device. The regenerated analog signals are modified along the two paths by each normalizing signal, respectively, and a modified signal drives each display device to provide visual displays of the normalized optical density curve and the normalized area under the optical density curve, respectively.

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Beaumont, TX, United States of America

Gene A Butts