Shimadzu Corporation

Yugo Ishihara

Takuya Yonekura

Masato Watanabe

Hajime Bungo

Shinji Tsuji

Hiroyuki Togo

Atsushi Sakamoto

A detector for a chromatograph includes a light source, and a light detector that detects light generated based on turning on of the light source, wherein the light source includes a deuterium lamp, and a deuterium lamp power supply circuit connected to the deuterium lamp, and the deuterium lamp power supply circuit includes a DC voltage generation circuit that generates a DC voltage by performing a switching operation, a rectifying operation and a smoothing operation, a voltage application circuit that applies a DC voltage generated by the DC voltage generation circuit to the deuterium lamp, a first feedback circuit that feeds a first feedback voltage changing depending on a DC voltage to the DC voltage generation circuit such that the DC voltage generated by the DC voltage generation circuit becomes close to a discharge maintaining voltage, after electric discharge of the deuterium lamp is started, and a constant current control circuit that controls a discharge current of the deuterium lamp to be constant.

Detector for chromatograph

The device is provided with a lamp lighting unit configured to perform an operation for lighting a deuterium lamp by controlling a lamp drive unit and a heater drive unit, an abnormality determination unit configured to determine, in a prescribed sequence, whether or not a voltage or a current detected by a lamp voltage detection unit, a lamp current detection unit, a heater voltage detection unit, and a heater current detection unit is abnormal, and an abnormality cause identification unit configured to identify, in a case the voltage or the current is determined to be abnormal by the abnormality determination, the cause of the abnormality, based on the timing at which the abnormality determination unit determines that the voltage or the current is abnormal.

Device with deuterium lamp and liquid chromatograph

A load switch circuit for turning on and off supply of DC power to a load circuit of a chromatograph apparatus, the load switch circuit comprising: a first switching element connected to between a first node that receives DC voltage and the load circuit, the first switching element including a control terminal that receives a potential of a second node; a capacitive element connected to between the first and second nodes; a first resistive element connected to between the first and second nodes; and a bypass circuit configured to pass current between the first and second nodes upon turn-off of the first switching element.

Chromatograph apparatus and load switch circuit

A spectroscopic detector includes a lamp house, a sample cell, an optical sensor, a heater, a cooling fan, a temperature sensor, and a control device. The heater heats the lamp house while being directly or indirectly in contact with the lamp house containing a light source. The cooling fan is for cooling the lamp house. The temperature sensor is for detecting a temperature of the lamp house. The control device is configured to control operations of the light source, the heater, and the cooling fan. The control device includes a temperature control part configured to maintain a temperature of the lamp house while the light source is lit at a set temperature by controlling at least output of the heater based on a detection signal of the temperature sensor.

Spectroscopic detector

A PDAhas a plurality of light receiving elements. An A/D converterconverts an output signal from each of the light receiving elements of the PDA. A conversion processing unitsequentially executes, for the plurality of light receiving elements, a conversion process of converting an output signal from an identical one of the light receiving elements at least twice within a preset time range with the A/D converter, to acquire at least two output values. An average value calculation unitcalculates an average value of the at least two output values for each of the light receiving elements acquired by the process executed by the conversion processing unit

Optical unit and spectrometer provided with same

Provided is a deuterium lamp power supply circuit capable of preventing the application of a high switch-to-ground voltage to a switch when applying a voltage between a positive electrode and negative electrode to light a deuterium lamp. The power supply circuit includes a capacitor for applying a voltage between the positive electrode and the negative electrode, with one terminal of the capacitor being connected to the positive electrode; a power supply, installed between the capacitor and the negative electrode, for charging the capacitor; and a two-terminal switch connected in parallel to the power supply. The switch is placed at a location close to ground, and thus a high switch-to-ground voltage is not applied to the switch.

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Kyoto, Japan

Yugo Ishihara