JPH04177132A - Spectroscope - Google Patents

Abstract

PURPOSE:To measure a wide wavelength region with a single spectroscope by providing a spectral filter and a photodetector on the light path of the zero order diffracted light of a diffraction lattice within one spectroscope. CONSTITUTION:Spark discharge is generated between the tip of a discharge electrode N and a sample S to be set to a light source. The light from the light source is condensed on an incident slit 3 by a condensing lens 4. A photomultiplier tube 6 is arranged at the incident position of the regular reflected light of the light incident to a diffraction lattice 2, that is, zero order diffracted light and an interference filter 5 having characteristics transmitting the bright line light of an element incapable of being detected by photomultiplier tubes P1, P2... but required in analysis is arranged in front of the photomultiplier tube 6. By this constitution, the zero order diffracted light containing the full- wave component of incident light as it is passed through the filter 5 to be capable of being spectrally diffracted. The filter 5 can be arranged in a spectroscope and the light out of the spectral wavelength range of the lattice 2 can be spectrally measured in the same spectroscope and a wide range can be measured with one spectroscope.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improvement of a spectrometer used in an emission spectrometer or the like.

(Prior art) In a spectrometer using a diffraction grating, the wavelength range in which spectroscopic measurements can be made is determined by the diffraction grating, and when measuring in a wavelength range exceeding that wavelength range, it is necessary to replace the diffraction grating. With conventional emission spectrometers, spectroscopic measurements using diffraction gratings are possible up to wavelengths of about 40 Qnm, and a multi-wavelength spectrometer that simultaneously measures multiple emission lines on the spectral image plane is used, making it possible to measure wavelengths from 400 nm onwards. (Na,
For the detection and quantification of alkaline elements such as 5Li, we have added a spectrometer specifically designed for long wavelengths.

(Problems to be solved by the invention) As mentioned above, if two spectrometers are used to widen the measurement wavelength range, there is a problem that the installation area of the device becomes large, and the two spectrometers on the light source side have to transmit light respectively. There is a problem that the equipment required to be introduced makes the entire device complicated and expensive.The present invention aims to provide a single wide wavelength range spectrometer that solves these problems.

(Means for Solving the Problems) In one diffraction grating spectrometer, a spectroscopic filter was installed on the optical path of the 0th order diffracted light of the diffraction grating, and a light receiving element was also placed behind the filter.

(Function) Conventionally, in spectroscopy using a diffraction grating, the 0th order diffracted light was considered to be a nuisance and was absorbed and removed by an optical trap or the like.

Since the 0th-order diffracted light contains all the wavelength components of the incident light, it can be separated into spectra by passing it through a filter.The filter can be installed inside a spectrometer, so this allows the spectral wavelength range of the diffraction grating to be Since there is only one spectrometer that can measure the spectra of outside light within the same spectrometer, there is no need for equipment to guide light to two spectrometers on the light source side, and the given problem can be solved. It turns out.

(Embodiment) In Figure 0, which shows an embodiment of the present invention, 1 is an outer casing of a spectrometer, 2 is a diffraction grating, 3 is a light entrance slit, PL,
P2. ...is the wavelength of the emission line of the element to be analyzed on the spectral image plane formed by the diffraction grating in the photomultiplier tube! It is located in S is a sample, N is a discharge electrode, a spark discharge is caused between the tip of the electrode and the sample S, and the spark discharge is used as a light source. 4 is a condensing lens that focuses the spark discharge light onto the entrance slit 3.The configuration of 0 or more is basically the same as a conventional emission spectrometer.
The features of the present invention reside in the interference filter 5 and the photomultiplier tube 6 placed behind it. The photomultiplier tube 6 is the diffraction grating 2
The interference filter 5 is placed in front of the photomultiplier tube 6. The interference filter 5 is placed in front of the photomultiplier tube 6. The interference filter 5 is placed in front of the photomultiplier tube 6. The interference filter 5 includes photomultiplier tubes P1, P2 . ..., an element that cannot be detected but has the property of transmitting the bright line light of the element to be analyzed is selected. As a result, spectroscopic measurement of light exceeding the wavelength range that can be separated by the diffraction grating 2 is performed by the filter 5 and photomultiplier tube 6 system.

(Effect of the invention) Conventionally, in such cases, an optical fiber was inserted closely between the sample S and the electrode N to guide the light to another spectrometer, but according to the present invention, one Since the filter 5 and the light-receiving element are simply installed inside the spectrometer, there is no need to increase the size of the analyzer itself and have trouble finding a place to install it. It is not expensive and can measure a wide range that could not be done with a single conventional spectrometer.

[Brief explanation of drawings]

The drawing is a plan view of an apparatus according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Housing, 2-- Diffraction grating, 3... Entrance slit, 4... Condensing lens, 5... Filter, 6... Photomultiplier tube, S... Sample, N ...discharge electrode, PL,
P2. ...Photomultiplier tube. Agent: Hiroshi Agata, patent attorney

Claims (1)

[Claims] In a diffraction grating spectrometer, in addition to the light receiving element that receives the spectrum light formed by the diffraction grating, a light receiving element is also placed on the optical path of the O-order diffracted light of the diffraction grating, and the measurement is performed in front of the light receiving element. A spectrometer characterized by inserting and arranging a filter that transmits light of a certain wavelength.