Abstract:
The present invention relates to an improved dual beam multichannel spectrophotomer employing a simple and novel optical system in combination with photodiode arrays and a unique logrithmic data converter to convert light signals to absorbance. In particular, the optical system utilizes optical elements in a novel arrangement to direct a pair of equivalent sample and reference beams in an essentially parallel formation respectively through a sample and reference cell and to focus and direct the emergent sample and reference beams to a single flat horizontally ruled grating which disperses each of the sample and reference beams respectively onto a pair of vertically disposed photodiode arrays whereby the light signals are converted into absorbance units (AU) by an unique logarithmic data converter. The spectrophotometer is highly accurate, has very low drift, less than 2.times.10.sup.-4 AU/.degree.C., and very low noise, less than .+-.2.times.10.sup.-5 AU. The dual beam multichannel spectrophotomer is particularly suitable for use in high pressure liquid chromatography to record the absorbance spectrum of the samples as they are being eluted from the chromatographic column.
Abstract:
An automatic chemical analyzer for the analysis of physiological samples. A scanning monochromatic spectrophotometer may be used to determine the absorbance of the sample under control of a central processing unit. Outputs from one of several ion selective electrodes may also be selected by the system. The information obtained from the measurements is stored in memory or ouputted to output devices. Information about the test parameters may be read from an optical bar code associated with the test kit for the particular chemical analysis.
Abstract:
A method and means for operating log converter circuits in which the method comprises the steps of sequentially conducting to the input of the log converter circuit signals representing a known transmittance (T) of 100% T, 10% T, 1% T, and 0.1% T, these signals covering the range of operation of the log converter circuit, storing the outputs of the circuit as signals representing an absorbance (A) of 0A, 1A, 2A, and 3A, respectively, conducting to the input of the log converter circuit an unknown signal, and utilizing a microcomputer to perform a linear interpolation of the output of the circuit with the unknown signal applied thereto using the previously stored 0A, 1A, 2A, and 3A signals.
Abstract:
A non-invasive blood constituents measuring instrument measures blood constituent values including blood glucose concentration in a living body non-invasively. The instrument is composed of a light source 11 to irradiate a light containing plural wavelengths to a living body 13, a light receiver 14 to detect the light transmitted through a living body or reflected and scattered thereon, a spectrum analyzer 15 to analyze the light transmitted through the living body or reflected thereon at different times, a subtraction processor 18 to generate spectrum subtraction from the spectrum of the light at the different times measured by the spectrum analyzer 15, and a blood glucose concentration predictor 21 into which the output data of the subtraction processor 18 are input and which outputs a blood constituent value.
Abstract:
A toner depositing amount measuring apparatus for measuring the amount of toner deposited on a photosensitive drum includes a light source for irradiating the surface of the photosensitive drum with light and a photoelectric converting section for receiving the reflected light and converting the received reflected light into an electric signal. A logarithmic calculation is applied to the output signal of the photoelectric converting section in a logarithm-compressing section. The temperature characteristics of the logarithm-compressing section are compensated for in a temperature compensating section. The amount of the toner deposition is calculated in a toner depositing amount calculating section based on a difference between the data during non-deposition of the toner and the data during deposition of the toner, the data being obtained from the logarithm-compressing section. Further, image forming conditions are changed in a control section in accordance with an output signal denoting the calculated deposition amount of the toner so as to control the density of the image formed.
Abstract:
A non-invasive blood constituents measuring instrument measures blood constituent values including blood glucose concentration in a living body. The instrument is composed of a light source 11 to irradiate a light containing plural wavelengths to a living body 13, a light detector 14 to detect the light transmitted through a living body or reflected thereon, an instantaneous spectrum analyzer 15 to analyze the light transmitted through the living body or reflected thereon at different times, a subtraction processor 18 to generate spectrum subtraction from the spectrum of the light at the different times measured by the spectrum analyzer 15, and a blood glucose concentration predictor 21 into which the output data of the subtraction processor 18 are input and which outputs a blood constituent value.
Abstract:
A toner depositing amount measuring apparatus for measuring the amount of a toner deposited on a photosensitive drum (2) includes a light source (53) for irradiating the surface of the photosensitive drum (2) with light and a photoelectric converting section (54) for receiving the reflected light and converting the received reflected light into an electric signal. A logarithmic calculation is applied to the output signal of the photoelectric converting section (54) in a logarithm-compressing section (58). The temperature characteristics of the logarithm-compressing section (58) are compensated in a temperature compensating section (59). The amount of the toner deposition is calculated in a toner depositing amount calculating section (43) based on a difference between the data during non-deposition of the toner and the data during deposition of the toner, the data being obtained from the logarithm-compressing section (58). Further, image forming conditions are changed in a control section (36) in accordance with an output signal denoting the calculated deposition amount of the toner so as to control the density of the image formed.