CN115014516A

CN115014516A - Multi-monochromator spectrometer device

Info

Publication number: CN115014516A
Application number: CN202210451715.3A
Authority: CN
Inventors: 彭振坚; 李燕; 虞建栋
Original assignee: Hangzhou Everuping Optics Co ltd
Current assignee: Hangzhou Everuping Optics Co ltd
Priority date: 2022-04-27
Filing date: 2022-04-27
Publication date: 2022-09-06

Abstract

The invention discloses a multi-monochromator spectrometer device, and aims to overcome the defects of high precision requirement and high cost of the existing method for removing stray light. The grating comprises a base and a grating seat, wherein the grating seat is rotationally connected with the base, the grating seat comprises at least two gratings, the base comprises a plurality of optical elements, the base is provided with a main light path, the main light path comprises a plurality of light splitting paths, each light splitting path comprises a first light path and a second light path, the first light path is an incident light path corresponding to the grating, the second light path is an emergent light path corresponding to the grating, included angles between the first light path of each light splitting path and the corresponding grating are the same, in an application state, light generated by a light source is emitted to the grating along the first light path in parallel collimated light beams, and the base is provided with a light detection device at the tail end of the main light path. The device has high-efficiency light filtering capability, and improves the precision on the premise of reducing the cost.

Description

Multi-monochromator spectrometer device

Technical Field

The present invention relates to spectrometer arrangements, and more particularly, it relates to a multi-monochromator spectrometer arrangement.

Background

In ultraviolet measurement, stray light has a great influence on a test result, the stray light inhibition capability of a traditional monochromator spectrometer cannot meet the requirement of precision measurement, so that a double-cascade monochromator needs to be adopted for light splitting and then measurement, an existing double-monochromator spectrometer implementation scheme usually adopts two independent monochromators connected in series, and in order to ensure measurement synchronism, requirements on mechanical manufacturing, installation and adjustment and software control are high, so that the cost is high.

Disclosure of Invention

The invention overcomes the defects of high precision requirement and high cost of the existing method for removing the stray light, and provides the multi-monochromator spectrometer device which has the advantages of high measurement precision, compact structure, easy manufacture and convenient use.

In order to solve the technical problem, the invention adopts the following technical scheme:

a multi-monochromator spectrometer device comprises a base and a grating seat, wherein the grating seat is rotatably connected with the base and comprises at least two gratings, the base comprises a plurality of optical elements, the base is provided with a main light path, the main light path comprises a plurality of light splitting paths, and the light splitting paths are formed by the optical elements;

the quantity of beam splitting way adapts to grating quantity, the beam splitting way includes first light path and second light path, and first light path is for corresponding the incident light path of grating, the second light path is for corresponding the emergent light path of grating, the first light path of each beam splitting way with correspond the contained angle of grating is the same, and under the application state, the light that the light source produced is along first light path is with parallel collimated light beam outgoing extremely the grating, the base is in the end of main light path is equipped with light detection device.

The monochromator is a common light splitting instrument, and utilizes a dispersion element to split polychromatic light into quasi-monochromatic light, so that a series of independent monochromatic light with a narrow enough spectral interval can be output. By arranging more than two gratings and keeping the included angle between the first light path of the light splitting path and the grating the same, the gratings are completely synchronous when spectrum signals with different wavelengths are scanned and measured, and stray light can be better filtered. The two gratings move synchronously along with the grating seat, the synchronism is good, the requirements of mechanical manufacture, installation and debugging and software control can be greatly simplified, and the cost is reduced.

Preferably, the optical element comprises a filter, the filter being located on the primary light path. The stray light outside the measuring waveband can be further eliminated, and the measuring precision is improved.

Preferably, the grating seat is an electric rotating seat.

Preferably, the light detection device is a silicon photodiode or a photomultiplier tube. The photomultiplier has high sensitivity and the silicon photodiode has good stability.

Preferably, the light detection device comprises a switching device and two photosensors, one of the photosensors is a silicon photodiode, and the other photosensor is a photomultiplier tube. The switching device switches the silicon photodiode or the photomultiplier, expands the measurement function of the instrument and improves the measurement precision.

Preferably, the grating is a planar reflective grating. The planar reflection grating has high cost performance, convenient use and high measurement precision.

Preferably, the base includes a diaphragm, and the main light path passes through the diaphragm. The diaphragm for eliminating stray light is arranged on the transmission light path, so that the influence of non-measurement light rays outside the transmission light path on the measurement result can be eliminated, and the measurement precision is improved.

Preferably, the number of the gratings is two, the grating holder includes a first grating and a second grating, the optical element includes a first slit, a second slit, a third slit, a first concave mirror, a second concave mirror, a third concave mirror and a fourth concave mirror, and in an application state, light generated by the light source sequentially passes through a transmission light path of the first slit, a transmission light path of the first concave mirror, a transmission light path of the first grating, a transmission light path of the second concave mirror, a transmission light path of the second slit, a transmission light path of the third concave mirror, a transmission light path of the second grating, a transmission light path of the fourth concave mirror and a transmission light path of the third slit and finally emits to the optical detection device.

Preferably, the grating is provided with a working surface, the normals of the working surfaces of the two gratings are parallel, and the included angle between the normals of the working surfaces of the two gratings is 180 degrees.

Compared with the prior art, the invention has the beneficial effects that: through with two fixed settings of grating on the grating seat, make the incident angle of two gratings the same through designing the light path for have efficient filtering ability, improved the precision under the prerequisite of reduce cost.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

in the figure:

the optical module comprises a housing 1, a base 10, a light inlet 11, a grating base 2, a grating 21, a first grating 211, a second grating 212, a main light path 3, a light splitting path 31, a first light path 311, a second light path 312, a light detection device 4, a filter 51, a diaphragm 52, a first slit 531, a second slit 532, a third slit 533, a first concave mirror 541, a second concave mirror 542, a third concave mirror 543, a fourth concave mirror 544, a first plane mirror 551, a second plane mirror 552, and a light shielding plate 6.

Detailed Description

The present disclosure is further described with reference to the following drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

In the present disclosure, terms such as "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "side", "bottom", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only relational terms determined for convenience in describing structural relationships of the parts or elements of the present disclosure, and do not refer to any parts or elements of the present disclosure, and are not to be construed as limiting the present disclosure.

In the present disclosure, terms such as "fixedly connected," "connected," and the like should be understood broadly, and mean that they may be fixedly connected, integrally connected, or detachably connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present disclosure can be determined on a case-by-case basis by persons skilled in the relevant art or technicians, and are not to be construed as limitations of the present disclosure.

Example (b):

a multi-monochromator spectrometer device, as shown in FIG. 1, comprises a closed and light-tight housing 1, the housing 1 having a base 10, a grating mount 2 rotatably connected to the base 10. In this embodiment, the grating seat 2 is rotatably connected to the base 10 via an electric rotating device, and the electric rotating device is coupled to the control circuit. At least two gratings 21 are provided on the grating mount 2. The base 10 has several optical elements at the periphery of the grating mount 2. The optical elements and the housing 1 form a main light path 3, the housing 1 has a light inlet 11, and light emitted by the light source enters from the light inlet 11, is filtered along the main light path 3, and is then emitted to the light detection device 4.

In the present embodiment, the number of the gratings 21 is 2, and the gratings 21 are planar reflection gratings 21. The grating mount 2 has a first grating 211 and a second grating 212 thereon. The two gratings 21 have the same distance to the axis of the grating seat 2. The normal lines of the working surfaces of the two gratings 21 are parallel, and the normal line included angle of the working surfaces of the two gratings 21 is 180 degrees.

In the present embodiment, the optical element includes a first slit 531, a second slit 532, a third slit 533, a first concave mirror 541, a second concave mirror 542, a third concave mirror 543, and a fourth concave mirror 544. The first slit 531 is located on the incident focus of the first concave mirror 541, the first concave mirror 541 is located on the emergent light path of the first slit 531, the first grating 211 is located on the emergent light path of the first concave mirror 541, the second concave mirror 542 is located on the emergent light path of the first grating 211, the second slit 532 is located on the emergent focus of the second concave mirror 542, the second slit 532 is located on the incident focus of the third concave mirror 543, the third concave mirror 543 is located on the emergent light path of the second slit 532, the second grating 212 is located on the emergent light path of the third concave mirror 543, the fourth concave mirror 544 is located on the emergent light path of the second grating 212, and the third slit 533 is located on the emergent focus of the fourth concave mirror 544; the light detection device 4 is located on the emergent light path of the third slit 533; the first grating 211 and the second grating 212 are fixed in relative positions, and the normal lines of the working surfaces of the first grating 211 and the second grating 212 are completely parallel and arranged in 180-degree opposite directions; the first plane mirror 551 is located on the transmission light path between the first slit 531 and the first concave mirror 541; the second plane mirror 552 is located on the transmission optical path between the third slit 533 and the fourth concave mirror 544.

In this embodiment, the slit widths of the first slit 531, the second slit 532, and the third slit 533 are 0.2mm, the focal lengths of the first concave mirror 541, the second concave mirror 542, the third concave mirror 543, and the fourth concave mirror 544 are 75mm, the groove densities of the first grating 211 and the second grating 212 are 1200 lines/mm, and the blazed wavelengths of the first grating 211 and the second grating 212 are 250 nm.

There is also a first planar mirror 551 between the first slit 531 and the first concave mirror 541 and a second planar mirror 552 between the fourth concave mirror 544 and the third slit 533. The first plane mirror 551 and the second plane mirror 552 are used to adjust the position of the light so that the light inlet 11 and the light detecting device 4 are installed at positions that do not interfere with each other. The base 10 has a light shielding plate 6, the first grating 211 and the second grating 212 are disposed on two sides of the light shielding plate 6, and the second slit 532 is opened on the light shielding plate 6.

Due to the positional relationship of the respective slits and the concave mirrors, the light rays of the respective concave mirrors toward the first grating 211 and the second grating 212 are parallel collimated light beams.

The device further comprises a filter 51, which filter 51 is arranged in the light path. In the present embodiment, the filter 51 is disposed on the incident light path of the first slit 531. In other embodiments, the filter 51 is located between the third slit 533 and the light detecting means 4. Wherein the filter 51 is an ultraviolet-transmissive, visible-infrared-cut interference film filter, and in other embodiments, the filter 51 is an ultraviolet-transmissive, visible-infrared-cut interference film filter.

In this embodiment, the apparatus further includes a diaphragm 52, and the diaphragm 52 is located on the main optical path 3, so as to eliminate the influence of non-measurement light outside the transmission optical path on the measurement result, and improve the measurement accuracy.

In this embodiment, the light detecting device 4 is a silicon photodiode, and in other embodiments, the light detecting device 4 is a photomultiplier tube. In other possible embodiments, the light detection means 4 comprise switching means and two photosensors, one being a silicon photodiode and the other being a photomultiplier tube. The switching device switches the photoelectric sensor receiving light according to the signal of the controller.

In other possible embodiments, the grating base 2 has a multi-layer structure, each layer has two gratings 21, and the two gratings 21 have the same length from the axis of the grating base 2. The normal lines of the working surfaces of the two gratings 21 are parallel, and the normal line included angle of the working surfaces of the two gratings 21 is 180 degrees. In other possible embodiments, the grating mount 2 has a two-layer structure. The grating 21 includes a first grating 211 and a second grating 212 of a first layer and a third grating 21 and a fourth grating 21 of a second layer. The optical elements in the corresponding layers are arranged similarly to the present embodiment.

The main optical path includes 2 light splitting paths 31, the light splitting path 31 includes a first optical path 311 and a second optical path 312, the first optical path 311 corresponds to the incident optical path of the grating, and the second optical path 312 corresponds to the emergent optical path of the grating. The light generated by the light source is emitted to each grating 21 along the first light path 311 as a parallel collimated light beam, and the incident angles of the light are the same. More filtering passes to improve accuracy.

In this embodiment, when the first grating 211 and the second grating 212 on the grating base 2 rotate to a certain angle, the measured light emitted by the sample passes through the first slit 531, is reflected by the first plane mirror 551, and then exits to the first concave mirror 541, and is reflected by the first concave mirror 541, and then exits to the first grating 211 as a parallel collimated light beam, after being split by the first grating 211, the light with the measured wavelength exits to the second concave mirror 542 as a parallel collimated light beam, and is reflected by the second concave mirror 542, and then converges to the second slit 532, and the light exiting from the second slit 532 exits to the third concave mirror 543, after being reflected by the third concave mirror 543, and then exits to the second grating 212 as a parallel collimated light beam, after being split by the second grating 212 again, the light with the measured wavelength exits to the fourth concave mirror 544 as a parallel collimated light beam, and after being reflected by the fourth concave mirror 544, and then converges to the third slit 533 by the second plane mirror 552, after being emitted through the third slit 533, the light is received by the optical detection device 4, a filter 51 may be disposed on an incident light path of the first slit 531 or an emitting light path between the third slit 533 and the optical detection device 4, and the filter 51 is disposed to further eliminate stray light outside a measurement wavelength band, thereby improving measurement accuracy.

The above-described embodiments are merely preferred embodiments of the present invention, which is not intended to be limiting in any way, and other variations and modifications are possible without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A multi-monochromator spectrometer device is characterized by comprising a base and a grating seat, wherein the grating seat is rotationally connected with the base and comprises at least two gratings, the base comprises a plurality of optical elements, the base is provided with a main light path, the main light path comprises a plurality of light splitting paths, and the light splitting paths are formed by the optical elements;

2. The multi-monochromator spectrometer device of claim 1, wherein the optical element comprises a filter, the filter being positioned in the primary light path.

3. The multi-monochromator spectrometer arrangement according to claim 1, wherein the grating mount is a motorized rotating mount.

4. The multi-monochromator spectrometer device according to claim 1, wherein the light detecting means is a silicon photodiode or a photomultiplier tube.

5. A multi-monochromator spectrometer apparatus according to claim 1, wherein the light detecting means comprises a switching means and two photosensors, one of which is a silicon photodiode and the other of which is a photomultiplier tube.

6. The multi-monochromator spectrometer arrangement of claim 1, wherein the grating is a planar reflection grating.

7. The multi-monochromator spectrometer apparatus according to claim 1, wherein the base comprises a diaphragm through which the primary light path passes.

8. The multi-monochromator spectrometer device of claim 1, wherein the number of gratings is two, the grating mount comprises a first grating and a second grating, the optical element comprises a first slit, a second slit, a third slit, a first concave mirror, a second concave mirror, a third concave mirror and a fourth concave mirror, and in an application state, light generated by the light source sequentially passes through the transmission light path of the first slit, the transmission light path of the first concave mirror, the transmission light path of the first grating, the transmission light path of the second concave mirror, the transmission light path of the second slit, the transmission light path of the third concave mirror, the transmission light path of the second grating, the transmission light path of the fourth concave mirror and the transmission light path of the third slit, and finally emits to the light detection device.

9. The multi-monochromator spectrometer arrangement of claim 8, wherein the gratings have working surfaces, the normals of the working surfaces of the two gratings are parallel, and the normal angle of the working surfaces of the two gratings is 180 degrees.