JPH0711988B2 - Light source device for spectroscopic analyzer - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a light source device for a spectroscopic analysis device, which is suitable as a light source part of a device for performing spectroscopic analysis such as absorption and fluorescence.

[Technical background of the invention] Generally, a halogen tungsten lamp, a deuterium lamp, a light source unit of a device used for spectroscopic analysis of light absorption, fluorescence, etc.
Xenon arc lamps are mainly used.

However, in recent years, there have been demands for maintainability, labor saving, compactness, etc. of the device, but the above-mentioned lamps cannot sufficiently cope with these demands.

However, all these lamps are said to have good stability because they are of the DC lighting type.

Recently, xenon flash lamps, which were said to be a step ahead of stability in the past, have come to the fore. This is based on the reason that the xenon flash lamp is small, has high brightness, and has a long lighting life, and its practical application is currently under consideration.

[Problems of the Background Art] Although the xenon flash lamp has the great advantages as described above, it has technically difficult problems.

That is, the lamp must be lit by a pulse lighting method instead of the direct current lighting method like the conventional lamps, and a high voltage power supply unit for applying a high voltage is required at the time of light emission.

The structure and operating principle of the xenon flash lamp will be described here. As shown in FIG. 3, it will be described later between a cathode 2 and an anode 3 provided in a tube 1 in which xenon gas is filled (usually 1 atm). When a high voltage is applied by the high-voltage power supply unit and the trigger 2 induces a cathode 2,
Plasma is discharged between the anodes 3 to obtain high-luminance light. In this case, the light emission time is set to several μsec to several tens μsec and the light emission interval is set to several Hz to several hundred Hz, which is a general usage.

4 and 5 show a conventional light source device for a spectroscopic analysis device.

The device shown in FIG. 4 includes a timing pulse generating circuit 5, a light emitting section 6a of a photocoupler 6, and a light emitting section based on a timing pulse generated by the timing pulse generating circuit 5.
A signal generating section A composed of a control transistor 7 for controlling the energization current of 6a to emit light as a lighting signal from the light emitting section 6a, and a light receiving section of a photocoupler 6 for receiving the light from the light emitting section 6a. 6b, a trigger generation circuit 8 that generates a trigger signal based on the output of the light receiving unit 6b, and a trigger terminal 4 of the xenon flash lamp XeL based on this trigger signal.
It has a high voltage power supply section B composed of a trigger terminal drive circuit 9 for driving a high voltage circuit and a high voltage circuit 10 for applying a high voltage to the xenon flash lamp XeL.

The trigger terminal drive circuit 9 includes a thyristor SCR which is electrically connected by inputting a trigger signal to the gate, and a transformer T in which a drive voltage of the trigger terminal 4 is induced on the secondary side based on the conduction of the thyristor SCR.

In the light source device for a spectroscopic analyzer configured as described above, the signal generating unit A and the high-voltage power supply unit B are optically coupled by the light emitting unit 6a and the light receiving unit 6b of the photocoupler 6, and the xenon flash lamp is generated based on the timing pulse. XeL trigger terminal 4
Is excited to emit light.

However, in the case of this device, the pattern on the substrate forming the trigger generation circuit 8 of the high-voltage power supply section B picks up electromagnetic noise due to the light emission of the light emitting section 6a, which causes malfunction of the trigger generation circuit 8 and the trigger terminal drive circuit 9. However, there is a problem in that accurate spectroscopic analysis is hindered by noise and noise.

Therefore, as shown in FIG. 5, the high-voltage power supply section B is electromagnetically shielded by being placed in a case 11 formed of a metal having a high magnetic permeability, and the signal generating section A and the high-voltage power supply section B are connected by a shield wire 12. A xenon flash lamp power supply device is also possible.

However, in this case as well, the shielded wire 12 picks up electromagnetic noise due to abrupt current change and voltage change of the signal generating section A, and does not completely shield the signal generating section A and the high-voltage power supply section B electromagnetically. It was difficult.

[Object of the Invention] The present invention has been made in view of the above circumstances, and does not pick up noise at all during signal transmission in a signal generation unit or a high-voltage power supply unit, and thus contributes to accurate spectroscopic analysis without malfunction. It is an object of the present invention to provide a light source device for a spectroscopic analysis device to be obtained.

[Summary of the Invention] The summary of the present invention for achieving the above object comprises a xenon flash lamp, a high voltage circuit for supplying a high voltage to the xenon flash lamp, a transformer and a thyristor for driving a trigger terminal of the xenon flash lamp. A high-voltage power supply unit that electromagnetically shields a trigger terminal drive circuit and a trigger generation circuit that supplies a trigger signal to a thyristor of the trigger terminal drive circuit, and a lighting signal that determines a lighting condition of the xenon flash lamp. A signal generating section that electromagnetically shields the timing pulse generating circuit, a light emitting section that is provided in the signal generating section and outputs the lighting signal from the timing pulse generating circuit as light, and the high voltage power source section. , Receiving the light from the light emitting unit to the trigger generation circuit as an electric signal It is characterized in that it has a light receiving part for supplying and an optical fiber for connecting the light emitting part and the light receiving part.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIG. still,
In the apparatus shown in FIG. 1, parts having the same functions as those of the apparatus shown in FIG. 4 described above are designated by the same reference numerals, and detailed description thereof will be omitted.

The device shown in the same drawing is different from the device shown in FIG. 4 in that both the signal generator A and the high-voltage power supply B are electromagnetically shielded by being placed in cases 12 and 13 formed of a metal having a high magnetic permeability. At the same time, the light emitting portion 6a of the signal generating portion A and the light receiving portion 6b of the high voltage power source portion B are optically coupled by the optical fiber 14.

As shown in FIG. 2, the light emitting portion 6a and the optical fiber 14 are attached to a female contact 15a of an optical fiber connector in which the light emitting portion 6a is incorporated on the wall surface of the case 12 and the optical fiber 14 is attached.
The male contact 15b is attached to one end of the optical fiber 14 and the male contact 15b is fitted into the female contact 15a so that one end of the optical fiber 14 is optically coupled to the light emitting section 6a.

Similarly, the light-receiving portion 6b and the optical fiber 14 are optically coupled by mounting a female contact 16a having the light-receiving portion 6b built-in on the wall surface of the case 13 and by mounting a male contact 16b on the other end of the optical fiber 14. is there.

In the device configured as described above, the light from the light emitting section 6a of the signal generating section A is transmitted through the optical fiber 14 in the optical fiber connector.
Is received by the optical fiber 14, transmitted through the optical fiber 14, received by the light receiving portion 6b in the optical fiber connector on the side of the high-voltage power supply portion B, and then converted into an electric signal.

Therefore, the electromagnetic noise caused by the light emission of the light emitting portion 6a and the light reception of the light receiving portion 6b does not affect other circuit elements of the signal generating portion A and the high voltage power source portion B, and the signal generating portion A
Also, since both the high-voltage power supply section B and the high-voltage power supply section B are electromagnetically shielded, no external noise is picked up.

It goes without saying that the present invention is not limited to the scope of the above-described embodiments, and various modifications can be made within the scope of the gist thereof.

[Effects of the Invention] As described in detail above, according to the present invention, the signal generator and the high-voltage power supply are shielded respectively, and both are coupled through an optical fiber. It is possible to provide a light source device for a spectroscopic analysis device that does not pick up noise or extraneous noise at all and can contribute to accurate spectroscopic analysis without being affected by noise.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an enlarged schematic sectional view showing a coupling state between a light emitting portion and an optical fiber in the device shown in FIG. 1, and FIG. 3 is a xenon flash lamp. 4 is a block diagram showing a conventional light source device for a spectroscopic analysis device, and FIG. 5 is a block diagram showing another example of a conventional light source device for a spectroscopic analysis device. A: Signal generator, B: High voltage power supply, XeL: Xenon flash lamp, 6a: Light emitting part, 6b: Light receiving part, 14
…… Optical fiber, 15a, 16a …… Female contact, 15b, 16b…
… Male contact.

Claims (1)

[Claims] 1. A xenon flash lamp, a high voltage circuit for supplying a high voltage to the xenon flash lamp, a trigger terminal drive circuit including a transformer and a thyristor for driving a trigger terminal of the xenon flash lamp, and a thyristor of the trigger terminal drive circuit. A signal obtained by electromagnetically shielding a high-voltage power supply unit that electromagnetically shields a trigger generation circuit that supplies a trigger signal, and a timing pulse generation circuit that generates a lighting signal that determines the lighting conditions of the xenon flash lamp. A generation unit, a light emitting unit that is provided in the signal generation unit and outputs the lighting signal from the timing pulse generation circuit as light, and a high voltage power supply unit that is provided with the light from the light emission unit and receives an electrical signal. A light-receiving unit that supplies the trigger generating circuit as a light-emitting unit and a light-receiving unit. An optical fiber for connection, and a light source device for a spectroscopic analysis device.