Horiba, Ltd.

Masaru Tanaka

Naoki Noguchi

Kozo Ishida

Issei Yokoyama

Osamu Saitoh

Kiyoaki Hara

Kenji Yoshino

Two sets of TACs are simultaneously operated by a start pulse, one set of TACs using a photoelectron pulse due to an excited light from a sample as a stop pulse, and the other set of TACs using a photoelectron pulse due to a fluorescence from the sample as a stop pulse. Each TAC outputs a voltage proportional to the time from the start of action to the receiving of the stop pulse and an excitation light shape and a luminescence transient shape are simultaneously measured on the basis of output voltages from the TACs. A variable offset voltage is added to an output of at least one of the two sets of TACs and the excitation light shape and the luminescence transient shape are displayed on a two-picture synthetic display.

Apparatus for measuring luminescence lifetime

A multichannel time-voltage converter generates a plurality of output voltages which respectively corresponds to the time period between a start pulse and each of a plurality of stop pulses. A single sawtooth wave generator is utilized with a plurality of track and hold circuits so as to obviate the need for separately calibrating each of the plurality of channels of the converter.

Multichannel time-voltage converter

An apparatus for measuring the luminous lifetime samples, which eliminates the deviation of the time axis of each channel of a multichannel TAC, deviations resulting from differences the wiring or the time lag of the elements of each channel of the multichannel TAC constituting a principal part of the apparatus. The apparatus operates by adding a respective variable offset voltage to the output of each channel of the TAC and by regulating the offset voltage in every channel without using any delay element so as to eliminate the time axis deviations of the channels.

Apparatus for measuring the luminous lifetime of samples

An optical absorption analyzer for determining the concentration of low concentration components of a sample gas. Inexpensive voltage to frequency converters, up/down counters, and integrators are used to obtain a high accuracy determination which is independent of fluctuations in the strength of the light source used in the analyzer.

Optical absorption analyzer

An analyzer compensation circuit for compensating for the fluctuations in the intensity of the light source or for stains on the windows of cells in an analyzer. A pair of D-A converters are respectively connected to compensating and measuring light detectors. An up/down counter is arranged to count either up or down in response to the output of a comparator. The comparator compares the output of the D-A converter connected to the compensating detector with a reference value and the output of the up/down counter is connected to both of the D-A converters such that the output of the converter connected to the compensating detector is adjusted to be equal to the reference value. Since the other D-A converter is also connected to the output of the up/down counter, the output of the other D-A converter has been compensated for fluctuations in the light intensity or stains on the windows on cells used in the analyzer.

Analyzer compensation circuit

A fluorescent gas analyzer for analyzing gases by the fluorescence method. A flashtube which is operated in its pulse mode is used as a light source. First and second optical detectors respectively detect light of a first and second wavelength range, the light of the first wavelength range being emitted by the light source and the light of the second wavelength range being emitted from a gas sample irradiated by the light source. A pair of integrators respectively integrate the outputs of the first and second detectors. Processing means, including sample and hold circuits and a synchronous detector, are used to further process the signals so that the system output is independent of deterioration of the light source and fluctuations in the strength of the light source output and independent of stray capacitance effects.

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Kyoto, Japan

Masaru Tanaka