Polaroid Corporation

Seroptix, Inc.

Joseph M Canter

Yongwu Yang

Wanglong Zhou

Michael L Reisch

Martin A Agulnek

James S Harrison

William A Shelton

Michael A Greenwald

Melvin P Ehrlich

Michael Y Lu

Victor S Sapirstein

Omanand Koul

Eugene Katsman

A process for detecting HIV infection, Hepatitis A, B and C, and other similar infections in a plasma sample, wherein the process involves the use of an excitation laser source to irradiate upon the plasma sample an excitation laser beam to obtain a fluorescence emission spectrum of the plasma sample. The invention uses an excitation laser wavelength of about 355 nanometers. Detection of the fluorescence is made in the wavelength range from about 380 to 600 nanometers. The resulting spectrum of the sample is compared with the spectrum of a control which is free from infection. Analysis of the parameters of the emission spectra including, but not limited to, peak intensity wavelength, amplitude at the peak intensity, area ratio of left and right portions of the emission spectra, and shifts of the peak intensity wavelength, allows determination of HIV infection, Hepatitis A, B and C, and other similar infection in the plasma. Selective absorbents, such as C-M Affi Gel Blue and activated charcoal, may be used to treat the samples before fluorescence measurements, which is found to improve discrimination of infected and uninfected samples. The present invention is capable of detecting HIV infection at the stage when it is still undetectable by conventional diagnosis methods.

Apparatus and method for infectious disease detection

A quantitative process for monitoring female fertility cycle wherein the process involves directing a laser beam, preferably generated by a diode laser, onto an area of a slide containing an air-dried sample of a female body fluid. The diffraction pattern resulting from the sample is detected by a two-dimensional photo diode array and analyzed by a microprocessor. If a ferning pattern exists, such pattern will generate a characteristic structure in the diffraction pattern which is then detected by the photo diode array. If no ferning occurs, the corresponding diffraction pattern will be structureless. The microprocessor is programmed with an algorithm to produce a quantitative index of ferning indicating quantitatively the ferning level. Preferably, a plurality of spots on the sample are measured to determine the ferning level at each spot, and the microprocessor then makes a final determination as to final ferning level on the basis of the test results of all of the spots. This significantly increases the reliability of the final test result, since a defect at one test spot or anomaly of one test result will not be fatal to the final result.

Apparatus and method for monitoring ovulation

A control circuit for timing the duration of a flash of artificial illumination from an electronic flash maintains a substantially uniform amount of artificial illumination regardless of the ambient scene light intensity by detecting the ambient scene light intensity up to the instant that the flash is fired and thereafter subtracting the ambient scene light intensity so detected immediately prior to the flash being fired from the ambient and artificial scene light intensity detected during the flash of artificial illumination.

Control circuit for electronic flash

An electronic imaging system includes a linear LED array for recording on a photosensitive medium an image defined by electronic signal information in binary word format by simultaneously controlling the energization of all the LED's at a constant energy level in a series of intervals, each of which is timed differently to correspond to a different one of the data bits in the binary words which comprise the image defining electronic signal information. Each LED is energized during each interval as a direct function of the state of the data bit corresponding to that interval for that LED.

Parallel LED exposure control system

A photometric device for determining the exposure interval for a scene to be photographed includes a photometric array having a plurality of individual photocells that are each adapted to receive light reflected from a selected portion of the scene. Each photocell provides a signal output that is proportional to the light from the scene incident upon the cell. The outputs are each time integrated from the initiation of the exposure interval with the integrated results compared to a predetermined value representative of the desired exposure parameters for the film. A logic array terminates the exposure interval when a majority or median number of the time-integrated results indicate that the film exposure parameters for the respective portions of the scene have been met. The exposure interval is advantageously determined as a function of the median value of the light reflected from the scene rather than the average value and the exposure interval is thereby less affected by extreme variations in brightness.

Photometric device

A photometer for use in combination with a camera determines the optimum film exposure interval with the exposure interval corrected for differences in illuminance between a subject of principal interest in the central portion of the scene to be photographed and the subjects of secondary interest in the foreground and background portions of the scene. The photometer includes a photo-responsive array divided into three light receiving segments each having a field of view that generally corresponds to, respectively, the central portion, the foreground portion, and the background portion of the scene. Electronic circuitry, either in analog or digital form, is provided to select the maximum output of the background and foreground segments of the photo responsive array and compare the so-selected maximum output with the output of the central segment to increase the exposure interval when either the background or the foreground portion of the scene are more brightly illuminated than the subject of principal interest and decrease the exposure interval when the background or foreground portion of the scene are less brightly illuminated than the subject of principal interest. A photometer in accordance with the present invention is suitable for use with both conventional shutter mechanisms and time-integrating shutters.

Growing community of inventors

Lexington, MA, United States of America

Joseph M Canter