TWI677665B - Spectrum self-calibration grating and spectrometer - Google Patents

Abstract

A spectral self-calibrating grating includes a miniature grating and a correction mark. After the micro grating and the correction mark are illuminated by the light beam, a diffraction pattern and a correction pattern are formed on the imaging surface, respectively. The spectrum of the diffraction pattern is corrected according to the distance between the diffraction pattern and the correction pattern. A spectrometer using a spectral self-calibrating grating is also provided.

Description

Spectrum self-calibrating grating and spectrometer

The disclosure relates to a grating and a spectrometer, and in particular to a spectral self-calibrating grating and a spectrometer using the spectral self-calibrating grating.

Spectral analysis includes the advantages of non-destructive, chemical identification, wavelength flexibility, high sensitivity, and fast analysis speed. Therefore, the use of spectrometers to analyze various photophysical phenomena or photochemical phenomena of materials is increasing.

The spectrometer mainly uses the spectroscopic element to split the light, and receives the light beam from the spectroscopic element through the optical receiver, and then obtains the corresponding spectrum through the back-end operation. In recent years, mobile devices with computing and camera functions have become more and more popular. If the spectrometer and mobile device can be integrated, it will help reduce production costs and increase the popularity of applications. In the future, the development of portable spectrometers will have considerable market development. Great potential.

At present, there are technologies proposed to form a portable spectrometer by using a disc grating and a mobile phone, but this spectrometer has many problems. For example, when the light intensity of the incident light is too high, the light intensity of the different-color light intercepted by the light receiver may be oversaturated, resulting in excessive correction errors. In addition, because the optical disc grating is too crude to accurately split the light, the image captured by the optical receiver is blurred, the spectral position information cannot be correctly judged, and an erroneous spectrogram is generated.

Based on the above, how to reduce the correction error and improve the correctness of the judgment of the spectral position information has become an issue that researchers in this field want to solve.

The present disclosure provides a spectral self-calibrating grating, which is helpful for reducing correction errors and improving the accuracy of determining spectral position information.

This disclosure provides a spectrometer that can effectively correct the spectrum and determine the spectral position information.

A spectral self-aligning grating disclosed in the present disclosure includes a micro-grating and a calibration mark. After the micro grating and the correction mark are illuminated by the light beam, a diffraction pattern and a correction pattern are formed on the imaging surface, respectively. The spectrum of the diffraction pattern is corrected according to the distance between the diffraction pattern and the correction pattern.

A spectrometer of the present disclosure includes a spectral self-calibrating grating and a light receiver. The spectral self-calibrating grating includes a micro-grating and a calibration mark. After the micro grating and the correction mark are illuminated by the light beam, a diffraction pattern and a correction pattern are formed on the imaging surface of the light receiver, respectively. The spectrum of the diffraction pattern is corrected according to the distance between the diffraction pattern and the correction pattern.

In order to make the above-mentioned features and advantages of the present disclosure more comprehensible, embodiments are described below in detail with reference to the accompanying drawings.

The directional terms mentioned in the embodiments, such as: "up", "down", "front", "rear", "left", "right", etc., are merely directions referring to the drawings. Therefore, the directional terms used are used for illustration, but not for limiting the present invention. In the drawings, the drawings depict general features of methods, structures, and / or materials used in specific exemplary embodiments. However, these drawings should not be construed to define or limit the scope or nature covered by these exemplary embodiments. For example, for clarity, the relative size, thickness, and location of each film layer, region, and / or structure may be reduced or enlarged.

In the embodiments, the same or similar elements will be given the same or similar reference numerals, and their detailed description will be omitted. In addition, the features in the different exemplary embodiments can be combined with each other without conflict, and simple equivalent changes and modifications made according to the specification or the scope of the patent application are still within the scope of this patent. In addition, the terms "first" and "second" mentioned in this specification or the scope of patent application are only used to name discrete elements or to distinguish different embodiments or ranges, but not to limit the number of elements. The upper or lower limit is also not used to limit the manufacturing order or setting order of the components.

FIG. 1 is a schematic diagram of a spectrometer 1 according to an embodiment of the disclosure. FIG. 2 is a bottom view of the spectral self-aligning grating 10 of FIG. 1. 1 and FIG. 2, the spectrometer 1 includes a spectral self-calibrating grating 10 and a light receiver 11. The spectral self-aligning grating 10 includes a micro grating 100 and a correction mark 101. After the micro grating 100 and the correction mark 101 are irradiated by the light beam B, a diffraction pattern PD and a correction pattern PC are formed on the imaging surface 110 of the light receiver 11, respectively. The spectrum of the diffraction pattern PD is corrected according to the diffraction pattern PD (such as the first-order diffraction pattern PD1 of the diffraction pattern PD) and the distance between the correction patterns PC (such as the distance D11, the distance D12, and the distance D13).

In detail, the micro-grating 100 in the spectral self-calibrating grating 10 is suitable for expanding light (also referred to as different-color light) of different wavelengths in the light beam B (such as white light) in space (such as direction X). Specifically, after each colored light passes through the micro grating 100, a diffraction pattern of the 0th order diffraction pattern to the nth order diffraction pattern is formed, where n is an integer, for example, n can be ± 1, ± 2, ..., the absolute value of n The larger the distance from the 0th-order diffraction pattern, the weaker the light intensity. The following is for convenience of description, and n = 1 is taken as an example, but the present invention is not limited thereto.

According to the principle of diffraction, the 0th-order diffraction patterns of different colored lights will be imaged at the same position (Figure 1 uses the 0th-order diffraction pattern PD0 to represent the integration of the 0th-order diffraction patterns of different colored lights), and the same color light of different colors The distance between the order diffraction pattern and the 0th order diffraction pattern PD0 is positively related to the size of the wavelength of the colored light. In other words, the distance between the 1st-order diffraction pattern and the 0th-order diffraction pattern PD0 of the light beam with a longer wavelength will be greater than the 1st-order diffraction pattern and the 0th-order diffraction pattern PD0 of the light beam with a shorter wavelength. the distance between.

In FIG. 1, the first-order diffraction pattern PD1 represents the integration of the first-order diffraction patterns of different colored lights, and FIG. 1 schematically illustrates the first-order diffraction pattern PD11 of red light and the first-order diffraction of green light. The radiation pattern PD12 and the first-order diffraction pattern PD13 of blue light. Since the wavelength of red light is greater than the wavelength of green light, and the wavelength of green light is greater than the wavelength of blue light, the distance D11 between the first-order diffraction pattern PD11 and the 0th-order diffraction pattern PD0 is greater than the first-order diffraction pattern PD12. The distance D12 from the 0th-order diffraction pattern PD0, and the distance D12 between the 1st-order diffraction pattern PD12 and the 0th-order diffraction pattern PD0 is greater than the first-order diffraction pattern PD13 and the 0th-order diffraction pattern. The distance D13 between PD0.

Because the first-order diffraction patterns (such as the first-order diffraction pattern PD11, the first-order diffraction pattern PD12, or the first-order diffraction pattern PD13) of different colored lights are imaged at different positions on the light receiver 11, By setting the position of the imaging surface 110 of the light receiver 11 to at least overlap the position of the first-order diffraction pattern PD1, the position of the light receiver 11-the light intensity information (including each position of the light receiver 11) Corresponding light intensity and the distance between the first-order diffraction patterns of different-colored light are obtained from the relative position of the spectrum-the light intensity information.

However, the light intensity of the 0th-order diffraction pattern PD0 (that is, the sum of the light intensities of the 0th-order diffraction patterns of different colored lights) will be greater than that of any of the first-order diffraction patterns (such as the first-order diffraction pattern PD11, the first The light intensity of the first-order diffraction pattern PD12 or the first-order diffraction pattern PD13) is much higher. In the structure without the correction mark 101, if the position of the imaging surface 110 of the light receiver 11 is set to overlap with the position of the first-order diffraction pattern PD1, it also overlaps the position of the 0-order diffraction pattern PD0. , The light intensity intercepted by the light receiver 11 is easily oversaturated, and the light intensity of the first-order diffraction pattern of different colored light cannot be effectively identified, and the spectrum cannot be corrected. On the other hand, in order to avoid oversaturation of the light intensity intercepted by the light receiver 11, the position of the imaging surface 110 of the light receiver 11 is set not to overlap with the position of the 0th-order diffraction pattern PD0 (for example, only with the first order diffraction pattern PD0). The positions of the first-order diffraction patterns PD1 overlap), then the position-light intensity information obtained by the optical receiver 11 does not include the distance between the first-order diffraction patterns and the 0th-order diffraction patterns PD0 of light of different colors. Due to the lack of a reference position, the spectrometer can only obtain the relative position information of the spectrum, but cannot obtain the absolute position information of the spectrum (that is, it cannot know the actual wavelength corresponding to each light intensity). As a result, it is difficult to correct the spectrum correctly when the spectrometer is affected by environmental changes and produces an erroneous (offset) spectrogram.

In this embodiment, the position of the imaging surface 110 of the light receiver 11 is set to overlap with the position of the first-order diffraction pattern PD1 and also the position of the 0th-order diffraction pattern PD0 to obtain a spectral Absolute location information. In addition, the light intensity where the 0th-order diffraction pattern PD0 is located is reduced by setting the correction mark 101 to improve the problem of light intensity oversaturation.

In detail, the size of the correction mark 101 is designed so as not to cause a diffraction phenomenon to the light beam B. For example, the size (such as width and length) of the correction mark 101 is greater than 10 microns. In this way, the light beam B1 passes through the correction mark 101 to form a correction pattern PC (such as a shadow having a shape corresponding to the correction mark 101) on the imaging surface 110 of the light receiver 11. Since the correction pattern PC and the light beam B1 pass through the micro-grating 100 and the 0th-order diffraction pattern PD0 formed on the imaging surface 110 of the light receiver 11 is located in the correction sensing area R, the 0th order can be greatly reduced. The light intensity where the order diffraction pattern PD0 is located makes the light of the first order diffraction pattern (including the first order diffraction pattern PD11, the first order diffraction pattern PD12, and the first order diffraction pattern PD13) of each color light The intensity can be effectively identified. In addition, the center of the correction pattern PC can be used as a reference position. Due to the distance D between the imaging surface 110 and the micro-grating 100 (such as the distance required for the light beam to focus on the imaging surface 110 after passing through the micro-grating 100), the specifications of the micro-grating 100 (such as how many slits per centimeter, such as 200, 300 or 600 centimeters of slits (but not limited to this), the angle θ between the first-order diffraction beam (such as beam B2) and the beam (beam B1) passing through the micro-grating 100 and the correction mark 101 There is a dependency relationship, so the absolute position information of the spectrum and each absolute position (wavelength) can be obtained using the distance between the first-order diffraction pattern of different colored light and the reference position (such as distance D11, distance D12, and distance D13). The corresponding light intensity.

As a result, the spectrometer 1 is not easily affected by the saturation of light intensity, and can measure the absolute spectrum in different light measurement occasions, and can perform spectral correction based on the measured absolute spectrum, so in addition to reducing the correction error, Has the advantages of high environmental adaptability and high convenience. In addition, compared with a portable spectrometer using an optical disc grating, the spectrometer 1 can have a better spectroscopic ability, that is, a better spectroscopic resolution (the spectroscopic resolution can be adjusted by the specifications of the micro-grating 100) and a correction performance. Improve the accuracy of market position information and market competitiveness. In addition, due to the improvement of the spectral resolution and the correction performance, the spectrometer 1 can be applied to the verification fields of water, oil quality, and fluorescence. In addition, compared with the traditional spectrometer, in addition to the advantages of low cost and simple structure, the spectrometer 1 also has the advantage of small size, which is beneficial for integration with mobile devices (such as mobile phones, tablet computers, etc.). For example, when the spectrometer 1 is integrated with a mobile device, the camera module of the mobile device can be used as the light receiver 11 of the spectrometer 1.

According to different requirements, the spectral self-aligning grating 10 may optionally include other elements or films. For example, the spectral self-alignment grating 10 may further include a substrate 102, an optical layer 103, and a light-shielding layer 104. The optical layer 103 is disposed on the surface S1 of the substrate 102 facing the light receiver 11, and the optical layer 103 has a plurality of slits 1030 and a plurality of grooves 1031 having the same depth as the plurality of slits 1030. Please refer to FIG. 2 at the same time. In this embodiment, the plurality of slits 1030 are arranged along the direction X and extend along the direction Y, respectively. The micro grating 100 includes the plurality of slits 1030; the correction mark 101 includes the plurality of grooves 1031, and a shape on a plane formed by the direction X and the direction Y is, for example, a cross shape. The substrate 102 is a light-transmitting substrate, such as a glass substrate. The optical layer 103 is a light transmitting layer, such as polymethyl methacrylate (PMMA) or other high molecular polymers.

The light-shielding layer 104 is disposed on the surface S2 of the substrate 102 facing away from the light receiver 11, and the light-shielding layer 104 is provided so that the diffraction pattern PD formed on the imaging surface 110 includes only the 0th-order diffraction pattern PD0 of the micro-grating 100. And the first-order diffraction pattern PD1. In other words, the light-shielding layer 104 is arranged such that the diffraction patterns below the -1st order (such as the -1th order diffraction patterns to the -nth order diffraction patterns) and the diffraction patterns above the 2nd order (such as the second order Step diffraction patterns to the nth order diffraction patterns) are not imaged on the imaging surface 110. In this way, the subsequent calculation amount and operation power consumption can be reduced, and the operation speed can be improved. For example, the light-shielding layer 104 is made of a non-translucent material, and the light-shielding layer 104 has an opening 1040 that overlaps at least part of the correction mark 101 and at least part of the micro-grating 100 (the plurality of slits 1030 section).

It should be noted that the description of the above-mentioned elements or films is merely an example. According to different requirements, the above-mentioned elements or films may be added or omitted, and the materials and relative arrangement relationships of the above-mentioned elements or films (including the number, arrangement, Shape, size, etc.) can be changed as required. For example, the micro-grating 100 and the correction mark 101 may be disposed on the surface S2 of the substrate 102 facing away from the light receiver 11, and the light shielding layer 104 may be disposed on the surface S1 of the substrate 102 facing the light receiver 11. Alternatively, the micro-grating 100 and the correction mark 101 may be located on the same surface (such as the surface S1) of the same substrate (substrate 102) as shown in FIG. 1, or may be respectively located on different substrates. Alternatively, the shape of the correction mark 101 may be circular or other shapes in addition to the cross shape.

FIG. 3A to FIG. 3D and FIG. 3E to FIG. 3H are manufacturing flowcharts of the spectral self-calibration grating 10 in FIG. 2 along a section line A-A 'and a section line B-B', respectively. In one embodiment, the spectral self-aligning grating 10 is manufactured by using a semiconductor process technology. Please refer to FIGS. 3A to 3D (along the section line A-A '), and also refer to FIGS. 3E to 3H (along the section line B-B'). A yellow light process is used to form the substrate SUB to define FIG. 2 The pattern P of the plurality of slits 1030 and the plurality of grooves 1031 (FIGS. 3A and 3E). Next, the substrate SUB is subjected to, for example, an etching process to form a substrate SUB 'having a pattern P' corresponding to the plurality of slits 1030 and the plurality of grooves 1031 (FIGS. 3B and 3F). Then, the pattern P ′ of the substrate SUB ′ is transferred to the optical layer 103 ′ (FIGS. 3C and 3G) on the substrate 102 to form the optical layer 103 having the plurality of slits 1030 and the plurality of grooves 1031. (Figure 3D and Figure 3H). Finally, the light shielding layer 104 shown in FIG. 1 can be selectively formed on the substrate 102.

It should be noted that FIGS. 3A to 3H are only used to explain one of the manufacturing processes of the spectral self-aligning grating 10 of FIG. 2, but the manufacturing process or manufacturing method of the spectral self-aligning grating 10 is not limited thereto.

FIG. 4 is a schematic cross-sectional view of a spectrometer 2 according to another embodiment of the present disclosure. Please refer to FIG. 1 and FIG. 2. The main differences between the spectrometer 2 and the spectrometer 1 are as follows. In addition to the spectral self-aligning grating 10 and the light receiver 11, the spectrometer 2 further includes a housing 12, a collimating element 13, and a focusing element 14.

The housing 12 is housed on the light receiver 11 and houses a collimating element 13, a spectral self-alignment grating 10, and a focusing element 14 therein. In addition, the housing 12 has a slit 120 through which the light beam B passes. The collimating element 13 is provided on the transmission path of the light beam B from the slit 120 to collimate the light beam B from the slit 120. For example, the collimating element 13 may include at least one collimating lens, but is not limited thereto. The light-shielding layer 104 is provided between the collimating element 13 and the optical layer 103. The micro-grating 100 and the correction mark 101 are provided on the transmission path of the light beam B from the collimating element 13, and the micro-grating 100 and the correction mark 101 fall within the irradiation range of the light beam B from the collimating element 13. For example, at least part of the micro-grating 100 and at least part of the correction mark 101 fall within the irradiation range of the light beam B from the collimating element 13. The focusing element 14 is disposed on a transmission path of the light beams (such as the light beam B1 and the light beam B2) from the spectral self-aligning grating 10, and the focusing element 14 focuses the light beams from the spectral self-aligning grating 10 to the light receiver 11 to form a diffraction Pattern PD and correction pattern PC. For example, the focusing element 14 may include at least one focusing lens, but is not limited thereto.

FIG. 5 is a flowchart of a calibration operation of the spectrometer 2 of FIG. 4. Please refer to FIG. 4 and FIG. 5, when performing spectral self-correction, the light beam B enters the slit 120 (step 51) and is corrected into a fan-shaped beam transmitted from the single point to the collimating element 13. The collimating element 13 collimates the light beam B from the slit 120 (step 52) to form parallel light or approximately parallel light that is transmitted toward the spectral self-alignment grating 10. Next, the light beam B from the collimation element 13 is incident on the spectral self-alignment grating 10 (step 53), where the first part (for example, light beam B1) of the light beam B of the incident spectral self-alignment grating 10 passes through the micro-grating 100 and the correction mark 101 In addition, the second part (for example, the light beam B2) of the light beam B of the incident spectral self-alignment grating 10 forms a first-order diffraction light beam. The focusing element 14 focuses the light beam (including the light beam B1 and the light beam B2) from the spectral self-alignment grating 10 to the light receiver 11 (step 54) to form a diffraction pattern PD and a correction pattern PC. The light receiver 11 can convert light intensity into an image signal, and the image signal is transmitted to a processor (not shown) coupled to the light receiver 11. The processor then corrects the spectrum (step 55).

Specifically, the processor may capture a spectral image and calculate the absolute position information of the spectrum and the light intensity corresponding to each absolute position (wavelength) from the distance between the correction pattern PC and the first-order diffraction pattern of different colored light. . With this spectral correction, the spectral signal can be plotted and the spectral graph analyzed.

Figure 6 is a graph of the relationship between wavelength and light intensity, used to show the spectrum before and after correction. Please refer to FIG. 6, which shows the spectral signals before and after the correction of the light source of the deuterium lamp. The spectrum of a deuterium lamp light source is shifted to the wrong position (for example, more to the left than the correct position) due to environmental influences. However, after the aforementioned spectral self-calibration, the spectrum of the light source of the deuterium lamp can be corrected to the right back to the correct position.

To sum up, in the embodiment of the present disclosure, by using the design of the correction mark and the micro-grating, it is possible to obtain the absolute position information of the spectrum and the corresponding absolute position (wavelength) while improving the problem of light intensity oversaturation. Light intensity. As a result, the spectrometer is not easily affected by the saturation of light intensity, and can measure the absolute spectrum in different light measurement occasions, and can perform spectral correction based on the measured absolute spectrum, so in addition to reducing the calibration error, it also has High environmental adaptability and high convenience. In addition, the spectrometer can have a better spectroscopic ability, that is, a better spectroscopic resolution (the spectroscopic resolution can be adjusted by the specifications of the micro-grating) and correction performance, so it can improve the accuracy of judging the spectral position information and market competitiveness. In addition, due to the improvement of the spectral resolution and the correction performance, the spectrometer can be applied to the verification field that requires high spectral resolution. Moreover, in addition to the advantages of low cost and simple structure, the spectrometer also has the advantage of small size, which is conducive to integration with mobile devices (such as mobile phones, tablet computers, etc.). In one embodiment, a light-shielding layer may be further provided on the spectral self-calibrating grating to reduce the subsequent calculation amount and operation power consumption, and increase the operation speed.

Although the present disclosure has been disclosed as above by way of example, it is not intended to limit the present disclosure. Any person with ordinary knowledge in the technical field should make some changes and modifications without departing from the spirit and scope of the present disclosure. The scope of protection of this disclosure shall be determined by the scope of the attached patent application.

1, 2‧‧‧ spectrometer

10‧‧‧Spectral Self-Calibrating Grating

11‧‧‧ Optical Receiver

12‧‧‧ shell

13‧‧‧ Collimation element

14‧‧‧ focusing element

51, 52, 53, 54, 55‧‧‧ steps

100‧‧‧Micro Grating

101‧‧‧correction mark

102, SUB, SUB’‧‧‧ substrate

103、103’‧‧‧Optical layer

104‧‧‧Light-shielding layer

110‧‧‧ imaging surface

120, 1030‧‧‧ slit

1031‧‧‧Groove

1040‧‧‧Opening

B, B1, B2 ‧‧‧ Beams

D, D11, D12, D13 ‧‧‧ distance

P, P’‧‧‧ patterns

PC‧‧‧correction pattern

PD‧‧‧ Diffraction Pattern

PD0‧‧‧th-order diffraction pattern

PD1, PD11, PD12, PD13 ‧‧‧ first order diffraction pattern

R‧‧‧ Calibration sensing area

S1, S2‧‧‧ surface

X, Y‧‧‧ directions

θ‧‧‧ angle

A-A ’, B-B’‧‧‧ hatching

FIG. 1 is a schematic diagram of a spectrometer according to an embodiment of the disclosure.
FIG. 2 is a bottom view of the spectral self-aligning grating of FIG. 1. FIG.
FIG. 3A to FIG. 3D and FIG. 3E to FIG. 3H are manufacturing flowcharts of the spectral self-calibration grating in FIG. 2 along section lines AA ′ and B-B ′, respectively.
FIG. 4 is a schematic cross-sectional view of a spectrometer according to another embodiment of the present disclosure.
FIG. 5 is a flowchart of a calibration operation of the spectrometer of FIG. 4.
Figure 6 is a graph of the relationship between wavelength and light intensity, used to show the spectrum before and after correction.

Claims (15)

A spectral self-calibrating grating, including:
A micro-grating; and a correction mark, wherein the micro-grating and the correction mark are respectively irradiated with a light beam to form a diffraction pattern and a correction pattern on an imaging surface, according to the distance between the diffraction pattern and the correction pattern To correct the spectrum of the diffraction pattern. The spectral self-aligning grating according to item 1 of the scope of patent application, wherein the micro-grating and the correction mark are located on a surface of a substrate together. According to the spectral self-calibration grating described in item 1 of the patent application scope, wherein the micro-grating and the correction mark are respectively located on different substrates. The spectral self-aligning grating according to item 1 of the scope of patent application, wherein the micro-grating includes a plurality of slits, and the correction mark includes a groove having the same depth as each of the plurality of slits. The spectral self-calibrating grating according to item 1 of the scope of patent application, wherein the size of the correction mark is designed so as not to cause diffraction of the light beam. The spectral self-calibrating grating described in item 1 of the patent application scope further includes:
A light-shielding layer is provided so that the diffraction pattern formed on the imaging surface includes only the 0th-order diffraction pattern and the 1st-order diffraction pattern of the micro-grating. According to the spectral self-calibration grating described in item 1 of the scope of the patent application, wherein the correction pattern and the 0th-order diffraction pattern of the diffraction pattern are both located in a correction sensing area. A spectrometer including:
A spectral self-aligning grating including a micro-grating and a correction mark; and a light receiver, wherein the micro-grating and the correction mark are respectively irradiated with a light beam to form a diffraction pattern on an imaging surface of the light receiver and A correction pattern corrects a spectrum of the diffraction pattern according to the diffraction pattern and a distance between the correction patterns. The spectrometer according to item 8 of the scope of patent application, wherein the micro-grating and the correction mark are located on the same surface of the same substrate. The spectrometer according to item 8 of the scope of patent application, wherein the micro-grating and the correction mark are respectively located on different substrates. The spectrometer according to item 8 of the patent application scope, wherein the micro-grating includes a plurality of slits, and the correction mark includes a groove having the same depth as each of the slits. The spectrometer according to item 8 of the scope of patent application, wherein the size of the correction mark is designed so as not to cause diffraction of the light beam. The spectrometer according to item 8 of the scope of patent application, wherein the spectral self-calibrating grating further includes:
A light-shielding layer is provided so that the diffraction pattern formed on the imaging surface includes only the 0th-order diffraction pattern and the 1st-order diffraction pattern of the micro-grating. The spectrometer according to item 8 of the scope of the patent application, wherein the correction pattern and the 0th-order diffraction pattern of the diffraction pattern are both located in a correction sensing area. The spectrometer described in item 8 of the patent application scope further includes:
A collimation element is disposed on the transmission path of the light beam, wherein the micro-grating and the correction mark are disposed on the transmission path of the light beam from the collimating element, and the micro-grating and the correction mark collectively fall from the Within the irradiation range of the light beam of the collimating element.