Spectrometer noise reduction circuit

Abstract

The utility model relates to the technical field of electronics, in particular to a spectrograph noise reduction circuit, which is characterized in that a first end of an input module is connected with a spectrograph charge coupling signal, and a second end is connected with a first end of a leading edge double-sampling module; the second end of the leading edge double-sampling module is connected with the first end of the signal holding module, and the second end of the signal holding module is connected with the first end of the trailing edge double-sampling module; the second end of the trailing edge double-sampling module is connected with the output module; the leading edge double sampling module is used for carrying out leading edge correlation double sampling on the charge coupling signal of the spectrograph to obtain a leading edge signal; the back edge double sampling module is used for carrying out back edge correlation double sampling on the spectrometer charge coupling signal to obtain a back edge signal; the signal holding module is used for holding the leading edge signal and the trailing edge signal; and the output module is used for carrying out differential amplification on the leading edge signal and the trailing edge signal. The spectrograph noise reduction circuit can improve the signal-to-noise ratio of the charge coupled signal of the spectrograph, so that the performance of the spectrograph can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to electronic technical field, concretely relates to a spectrograph noise reduction circuit in electronic technical field. BACKGROUND

[0002] Charge-coupled Device (CCD) inside spectrograph inevitably produces noise when working. In the original signal of CCD output and working process, contain the inherent dark current noise in the image element, charge transfer noise, signal fluctuation noise, reset noise, horizontal clock crosstalk and the image sensor noise and flicker noise (1 / f) noise etc. In the related art, carry out noise reduction from the structure design of chip or adopt the noise reduction of correlation double sampling circuit, but the realization process of noise reduction circuit is more complex, and the effect of inhibiting interference is limited. SUMMARY

[0003] In order to solve the technical problem that the realization process of noise reduction circuit in prior art is more complex, and the effect of inhibiting interference is limited, the purpose of the utility model is to provide a spectrograph noise reduction circuit, and the technical scheme is as follows:

[0004] The utility model embodiment provides a spectrograph noise reduction circuit, the spectrograph noise reduction circuit includes:

[0005] Input module, front edge double sampling module, signal holding module, trailing edge double sampling module and output module, wherein:

[0006] The first end of the input module accesses spectrograph charge coupling signal, and the second end is connected with the first end of the front edge double sampling module;The second end of the front edge double sampling module is connected with the first end of the signal holding module, and the second end of the signal holding module is connected with the first end of the trailing edge double sampling module;The second end of the trailing edge double sampling module is connected with the output module;

[0007] The front edge double sampling module is used for carrying out front edge correlation double sampling to the spectrograph charge coupling signal and obtaining front edge signal;

[0008] The trailing edge double sampling module is used for carrying out trailing edge correlation double sampling to the spectrograph charge coupling signal and obtaining trailing edge signal;

[0009] The signal holding module is used for holding the front edge signal and the trailing edge signal;

[0010] The output module is used for differentially amplifying the front edge signal and the trailing edge signal.

[0011] In some possible implementation manners, the front edge double sampling module comprises a first power supply end, a second power supply end, a first switch, a second switch, a first capacitor and a second capacitor; wherein:

[0012] The first power supply end is connected with a first end of the first switch, a second end of the first switch is connected with a first end of the first capacitor, a second end of the first capacitor is connected with a first end of the second capacitor, a second end of the second capacitor is connected with a second end of the second switch, and a first end of the second switch is connected with the second power supply end.

[0013] In some possible implementation manners, the signal holding module comprises a first buffer and a second buffer; wherein:

[0014] A first end of the first buffer is connected with the second end of the first switch and the first end of the first capacitor respectively, and a second end of the first buffer is connected with a first end of the back edge double sampling module;

[0015] A first end of the second buffer is connected with the second end of the second switch and the first end of the second capacitor respectively, and a second end of the second buffer is connected with the first end of the back edge double sampling module.

[0016] In some possible implementation manners, the back edge double sampling module comprises a third switch, a fourth switch, a third capacitor and a fourth capacitor; wherein:

[0017] A first end of the third switch is connected with the second end of the first buffer, a second end of the third switch is connected with the first end of the third capacitor and the output module respectively, a first end of the fourth switch is connected with the second end of the second buffer, a second end of the fourth switch is connected with the second end of the fourth capacitor and the output module respectively, and a second end of the third capacitor is connected with a first end of the fourth capacitor.

[0018] In some possible implementation manners, the output module comprises a differential amplifier; wherein:

[0019] A first input end of the differential amplifier is connected with the second end of the third switch, and a second input end of the differential amplifier is connected with the second end of the fourth switch.

[0020] The differential amplifier is configured to subtract the front edge signal and the back edge signal and amplify a subtraction result.

[0021] In some possible implementation manners, the input module comprises a signal input port and an amplifier; wherein,

[0022] The signal input port is used for accessing the spectrometer charge coupled signal;

[0023] The input end of the amplifier is connected with the signal input port, and the output end of the amplifier is connected with the first end of the front edge double sampling module.

[0024] In some possible implementation manners, the front edge double sampling module is further used for subtracting the noise signal from the spectrometer charge coupled signal to obtain the front edge signal.

[0025] In some possible implementation manners, the rear edge double sampling module is further used for subtracting the noise signal from the spectrometer charge coupled signal to obtain the rear edge signal.

[0026] The utility model has the following beneficial effects: in the spectrometer noise reduction circuit, through the first end access spectrometer charge coupled signal of input module, second end with the first end connection of front edge double sampling module, the second end of the front edge double sampling module is connected with the first end of the signal maintaining module, and the second end of the signal maintaining module is connected with the first end of the rear edge double sampling module, and the second end of the rear edge double sampling module is connected with the output module, so that the front edge double sampling module can be realized, and the spectrometer charge coupled signal is carried out front edge correlation double sampling, and the front edge signal is obtained, the rear edge double sampling module is used for carrying out rear edge correlation double sampling to the spectrometer charge coupled signal, and the rear edge signal is obtained, so that the front edge signal in the front edge signal and the rear edge signal in the signal maintaining module can be increased, and finally the front edge signal and the rear edge signal are amplified in the output module, so that the effective signal output by the output module can be increased, the signal-to-noise ratio of the spectrometer charge coupled signal is improved, and the performance of the spectrometer can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical scheme and advantages of the embodiments of the utility model or the prior art, the drawings needed to be used in the embodiment or the prior art description will be briefly introduced as follows, and obviously, the drawings in the following description are only some embodiments of the utility model, and those skilled in the art can obtain other drawings according to these drawings without creating creative labor.

[0028] Figure 1 It is the component structure schematic diagram of a double sampling circuit provided in the related art,

[0029] Figure 2 It is the timing diagram of a double sampling circuit provided in the related art,

[0030] Figure 3 is a component structure schematic diagram of the spectrum instrument noise reduction circuit provided by the embodiment of the present application;

[0031] Figure 4 is another component structure schematic diagram of the spectrum instrument noise reduction circuit provided by the embodiment of the present application;

[0032] Figure 5 is a timing diagram of the spectrum instrument noise reduction circuit provided by the embodiment of the present application;

[0033] Figure 6 is another component structure schematic diagram of the spectrum instrument noise reduction circuit provided by the embodiment of the present application. DETAILED DESCRIPTION

[0034] In order to further illustrate the technical means and effects taken by the present application to achieve the predetermined purpose of the present application, the following describes the specific implementation, structure, features and effects of the spectrum instrument noise reduction circuit according to the present application in combination with the preferred embodiments and the drawings. Different "one embodiment" or "another embodiment" in the following description do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0035] In the description of the embodiments of the present application, unless otherwise specified, " / " represents the meaning of or, for example, A / B can represent A or B: the "and / or" in the text is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist together, and B exists alone, and in addition, in the description of the embodiments of the present application, "multiple" means two or more than two.

[0036] Hereinafter, the terms "first", "second" are only for descriptive purposes, and cannot be understood as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the art to which the present application belongs.

[0038] In the related art, there are two methods to reduce the noise of the CCD signal and improve the signal-to-noise ratio: the first method is to consider the structure design of the chip, such as using a buried groove process, using a phosphorus transfer injection storage area process, a multipinned phase (MPP) technology, and the like, to reduce the noise by improving the internal structure of the CCD chip. The second method is to use a more effective noise suppression method, such as the most commonly used correlated double sampling circuit (CDS) in the related art, as shown in Figure 1 The CDS circuit includes an input port for inputting a CCD analog signal, differential amplifiers 101 and 102 for signal holding and sampling, differential signals S1 and S2, and a differential amplifier 103 as an output terminal. In the CDS circuit, various noise disturbances are eliminated by accurately collecting the reset level and signal level of each pixel in real time, and signal extraction is completed. The circuit uses a two-stage sampling / holding circuit, the first stage is used to collect the reset level, i.e. the level at a certain time before the signal charge arrives after the reset pulse. The other stage is used to collect the pixel signal level, i.e. the level at a certain time before the signal charge arrives after the horizontal clock crosstalk. Then the two collected levels are differentially compared to obtain the actual signal level, while eliminating the reset pulse and horizontal clock interference. The timing signal corresponding to the CDS circuit is shown in Figure 2 The timing signal corresponding to the CDS circuit is shown in Figure 2 It can be seen that since the two level collections are related in time, as long as the two sampling points CSDCLK1 and CSDCLK2 are correctly selected, and the pulse switching time of the two collections is controlled within an appropriate range, the interference of various noises can be suppressed.

[0039] The specific scheme of the spectrum instrument noise reduction circuit provided by the present application will be described in detail below with reference to the accompanying drawings. Please refer to Figure 3 , which shows a composition structure schematic diagram of a spectrum instrument noise reduction circuit provided by an embodiment of the present application. The spectrum instrument noise reduction circuit 300 includes an input module 301, a front edge double sampling module 302, a signal holding module 303, a rear edge double sampling module 304, and an output module 305, wherein:

[0040] The first end of the input module 301 accesses the spectrometer charge-coupled signal, and the second end is connected with the first end of the front edge double sampling module 302; the second end of the front edge double sampling module 302 is connected with the first end of the signal holding module 303, and the second end of the signal holding module 303 is connected with the first end of the rear edge double sampling module 304; the second end of the rear edge double sampling module 304 is connected with the output module 305.

[0041] Here, the input module can be realized by a signal input port and an amplifier, amplifying the accessed spectrometer charge-coupled signal, and outputting the amplified analog signal. As shown in the figure, Figure 4 The input module can include a signal input port 401 and an amplifier 402 in the input module. Figure 4 The signal input port is used to access the spectrometer charge-coupled signal (i.e. the CCD signal in the input module). Figure 4 The input end of the amplifier is connected with the signal input port, and the output end of the amplifier is connected with the first end of the front edge double sampling module. In this way, by connecting the input end of the amplifier with the signal input port, the input spectrometer charge-coupled signal can be pre-amplified, and the amplified analog signal can be output to the front edge double sampling module.

[0042] The front edge double sampling module 302 is used for front edge related double sampling of the spectrometer charge-coupled signal to obtain a front edge signal.

[0043] The rear edge double sampling module 304 is used for rear edge related double sampling of the spectrometer charge-coupled signal to obtain a rear edge signal.

[0044] The signal holding module 303 is used for holding the front edge signal and the rear edge signal.

[0045] The output module 305 is used for differential amplification of the front edge signal and the rear edge signal.

[0046] Here, the front edge double sampling module 302 can be realized by connecting different power supply ends through two switches and two capacitors. As shown in the figure, Figure 4 The front edge double sampling module includes a first power supply end 41, a second power supply end 42, a first switch S0, a second switch S1, a first capacitor C1 and a second capacitor C2; wherein:

[0047] The first power supply end 41 is connected with the first end of the first switch S0, the second end of the first switch S0 is connected with the first end of the first capacitor C1, the second end of the first capacitor C1 is connected with the first end of the second capacitor C2, the second end of the second capacitor C2 is connected with the second end of the second switch S1, and the first end of the second switch S1 is connected with the second power supply end 42.

[0048] Here, one end of the first power supply end is connected with the first switch S0, and the other end is grounded; one end of the second power supply end is connected with the second switch S1, and the other end is grounded; in this way, the storage and release of the electric charge can be realized through the first switch S0 and the second switch S1, and the first capacitor and the second capacitor. When the first switch S0 is closed, the first capacitor is charged, and the charged current is provided to the signal holding module; when the first switch S0 is opened, the first capacitor is discharged, and the current in the signal holding module is released.

[0049] When the second switch S1 is closed, the second capacitor is charged, and the charged current is provided to the signal holding module; when the second switch S1 is opened, the second capacitor is discharged, and the current in the signal holding module is released. In this way, the front edge double sampling module is realized through the first power supply end, the second power supply end, the first switch, the second switch, the first capacitor and the second capacitor, so that in the front edge double sampling module, the front edge signal output from the front edge double sampling module to the signal holding module can be obtained by subtracting the noise signal from the spectrometer charge coupled signal, and then the front edge signal is sent to the output module through the signal holding module.

[0050] In some possible implementations, the signal holding module can be realized by two buffers, as shown in Figure 4 The signal holding module includes a first buffer 43 and a second buffer 44; wherein the first end of the first buffer 43 is connected with the second end of the first switch and the first end of the first capacitor respectively; the second end of the first buffer is connected with the first end of the trailing edge double sampling module; the first end of the second buffer 44 is connected with the second end of the second switch and the first end of the second capacitor respectively; and the second end of the second buffer is connected with the first end of the trailing edge double sampling module. In this way, the front edge signal obtained by subtracting the noise signal from the spectrometer charge coupled signal is output to the first buffer and the second buffer by the front edge double sampling module, so that the front edge signal is held in the first buffer and the second buffer, so that the trailing edge double sampling module can obtain the charging current from the first buffer and the second buffer.

[0051] In some possible implementations, the first buffer and the second buffer can be realized by the buffer AD783, and the sampling and holding of the signal can be realized by two AD783 buffers.

[0052] In some embodiments, the trailing edge double sampling module can be realized by two switches and two capacitors, as shown in Figure 4 The trailing edge double sampling module includes a third switch S3, a fourth switch S4, a third capacitor C3 and a fourth capacitor C4; wherein:

[0053] The first end of the third switch is connected with the second end of the first buffer, and the second end of the third switch is connected with the first end of the third capacitor and the output module respectively;

[0054] For example, the output module is realized by a differential amplifier, such as Figure 4 As shown, the output module includes a differential amplifier 45, and the second end of the third switch is connected with the first end of the third capacitor and the first input end of the differential amplifier respectively, so that the discharge current of the third capacitor C3 can be input into the differential amplifier through the first input end of the differential amplifier 45.

[0055] The first end of the fourth switch is connected with the second end of the second buffer, and the second end of the fourth switch is connected with the second end of the fourth capacitor and the output module respectively; and the second end of the third capacitor is connected with the first end of the fourth capacitor.

[0056] For example, the second end of the fourth switch is connected with the second end of the fourth capacitor and the second input end of the differential amplifier 45 respectively, so that the discharge current of the fourth capacitor can be output to the differential amplifier, and then the differential amplifier 45 subtracts the leading edge signal and the trailing edge signal, amplifies the subtraction result, realizes the signal doubling effect, and improves the signal-to-noise ratio of the output signal.

[0057] Through the third switch and the fourth switch, and the third capacitor and the fourth capacitor, the storage and release of electric charge can be realized. When the third switch is closed, the third capacitor is charged, and the charging current is provided to the signal holding module; when the third switch is opened, the third capacitor is discharged, and the current in the signal holding module is released to the differential amplifier 45.

[0058] When the fourth switch is closed, the fourth capacitor is charged, and the charging current is provided to the signal holding module; when the fourth switch is opened, the fourth capacitor is discharged, and the current in the signal holding module is released. In this way, the trailing edge double sampling module is realized through the third switch, the fourth switch, the third capacitor and the fourth capacitor, so that in the trailing edge double sampling module, the noise signal is subtracted from the spectrometer charge coupled signal to obtain the trailing edge signal, which is input to the differential amplifier through the second input end of the differential amplifier 45. In this way, since in the leading edge double sampling module, the noise signal is subtracted from the spectrometer charge coupled signal to obtain the leading edge signal, which is input to the differential amplifier through the first input end of the differential amplifier 45, the leading edge signal and the trailing edge signal are subtracted in the differential amplifier 45, and the subtraction result is amplified, so that the signal doubling effect is realized, and the signal-to-noise ratio of the output signal is improved.

[0059] Because the leading-edge signal is obtained by subtracting the noise signal from the spectrometer charge-coupled signal in the leading-edge double-sampling module, and the trailing-edge signal is obtained by subtracting the spectrometer charge-coupled signal from the noise signal in the trailing-edge double-sampling module, and because the leading-edge signal and the trailing-edge signal are subtracted in the differential amplifier 45 of the output module and the subtraction result is amplified, the signal can be doubled, making the signal twice its original size, while the noise signal is increased to its original size. This means the signal-to-noise ratio is increased by a factor of two. The noise suppression performance is improved by 40%.

[0060] In some possible implementations, the timing sequence of the first switch S0, the second switch S1, the third switch S3, and the fourth switch S3 is as follows: Figure 5 As shown, from Figure 5 It can be seen that the timing sequence of the first switch S0 and the third switch S2 is opposite, and the timing sequence of the second switch S1 and the fourth switch S3 is opposite; that is, when the first switch is closed, the third switch is open; when the second switch is closed, the fourth switch is open.

[0061] Among some possible implementations, Figure 4 The circuit shown can be used Figure 6 The component implementation shown is as follows: Figure 6 As shown, the input module pre-amplifies the CCD signal using amplifier AD8009 (i.e., amplifier 61), thereby outputting the amplified analog signal to the leading-edge double sampling module. Two analog switches, MAX4781, are used to implement the leading-edge and trailing-edge double sampling modules, enabling leading-edge and trailing-edge double sampling of the analog signal output from amplifier AD8009. A second amplifier, AD8009 (i.e., amplifier 62), buffers the leading-edge and trailing-edge signals. Then, two amplifiers, AD783, are used for signal sampling and holding, and the leading-edge and trailing-edge signals are output to differential amplifier LTC6362 for differential amplification. Finally, the signal output from differential amplifier LTC6362 undergoes analog-to-digital conversion to obtain the noise-reduced signal, which is then output.

[0062] exist Figure 6 In this circuit, the AD8009 amplifier (i.e., amplifier 61) and active devices form a third-order low-pass filter to filter out high-frequency noise. The MAX4781 and the second amplifier AD8009 (i.e., amplifier 62) form a two-channel correlation double sampling circuit to obtain the correlation double sampling signals of the signal leading edge and trailing edge, respectively. These signals are held by the AD783 and subtracted in the LTC6362, forming the spectrometer noise reduction circuit in this embodiment.

[0063] Since the correlation double sampling of the front edge of the CCD signal is to subtract the noise from the signal to obtain the front edge signal, and the double sampling of the rear edge is to subtract the signal from the noise to obtain the negative value of the rear edge signal, in this way, after the front edge signal and the rear edge signal are subtracted in the differential amplifier of the output module, the signal is increased to twice the original, and the noise signal is increased to less than twice, so that the signal-to-noise ratio of the output signal can be improved, and the performance of the spectrometer is further improved.

[0064] In addition, the embodiment of the utility model discloses a system, which can include a plurality of processing modules, when the system is applied to equipment, the processing module can be used to control and manage the action of the equipment. The storage module can be used to support the equipment to execute mutual program codes. The processing module can be a processor or a controller, which can realize or execute various exemplary logical blocks, modules and circuits described in combination with the disclosure of the utility model. The processor can also be a combination of computing functions, such as one or more microprocessor combinations, digital signal processing (Digital Signal Processing, DSP) and microprocessor combinations, etc. The storage module can be a memory.

[0065] In addition, the system provided by the embodiment of the utility model can be a chip, an assembly or a module. The chip can include a connected processor and a memory. The memory is used to store instructions. When the processor calls and executes the instructions, the chip can control the noise reduction circuit of the spectrometer in the above embodiments.

[0066] The system, computer-readable storage medium, computer program product or chip provided by the embodiment are used to execute the corresponding method provided above, so the beneficial effects that can be achieved are referred to the beneficial effects in the corresponding method provided above, which will not be described here. Through the description of the above embodiments, those skilled in the art can understand that, for the convenience and brevity of description, only the division of the above functional modules is taken as an example for illustration. In actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the system is divided into different functional modules to complete all or part of the functions described above. In the embodiments provided by the utility model, it should be understood that the disclosed system and method can be implemented in other ways. For example, the system embodiments described above are only illustrative, such as the division of modules or units, which is only a logical function division. In actual implementation, there can be another division way, such as combining or integrating multiple units or components into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed units can be through some interfaces, indirect coupling or communication connection between the units of the system, which can be electrical, mechanical or other forms.

[0067] It should be noted that the above-mentioned embodiments of the present application are only for description, and do not represent the advantages and disadvantages of the embodiments. The process depicted in the drawings does not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multiple task processing and parallel processing are also possible or may be advantageous. Each embodiment in the specification is described in a progressive manner, and the same or similar parts between each embodiment can be referred to each other, and each embodiment mainly explains the difference from other embodiments. The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application.

[0068] Although the embodiments of the present application have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the present application. Those skilled in the art can change, modify, replace and modify the above-mentioned embodiments within the scope of the present application without departing from the principles and purposes of the present application.

Claims

1. A spectrometer noise reduction circuit, characterized by, The spectrometer noise reduction circuit comprises an input module, a front edge double sampling module, a signal holding module, a rear edge double sampling module and an output module, wherein: The first end of the input module is connected to the spectrometer charge coupled signal, and the second end is connected to the first end of the front edge double sampling module; the second end of the front edge double sampling module is connected to the first end of the signal holding module, and the second end of the signal holding module is connected to the first end of the rear edge double sampling module; the second end of the rear edge double sampling module is connected to the output module; The front edge double sampling module is used for front edge correlated double sampling of the spectrometer charge coupled signal to obtain a front edge signal; The rear edge double sampling module is used for rear edge correlated double sampling of the spectrometer charge coupled signal to obtain a rear edge signal; The signal holding module is used for holding the front edge signal and the rear edge signal; The output module is used for differential amplification of the front edge signal and the rear edge signal.

2. A noise reduction circuit for a spectrometer according to claim 1, wherein, The front edge double sampling module comprises a first power supply end, a second power supply end, a first switch, a second switch, a first capacitor and a second capacitor, wherein: The first power supply end is connected to the first end of the first switch, the second end of the first switch is connected to the first end of the first capacitor, the second end of the first capacitor is connected to the first end of the second capacitor, the second end of the second capacitor is connected to the second end of the second switch, and the first end of the second switch is connected to the second power supply end.

3. The noise reduction circuit for a spectrometer of claim 1, wherein, The signal holding module comprises a first buffer and a second buffer, wherein: The first end of the first buffer is connected to the second end of the first switch and the first end of the first capacitor respectively; the second end of the first buffer is connected to the first end of the rear edge double sampling module; The first end of the second buffer is connected to the second end of the second switch and the first end of the second capacitor respectively; the second end of the second buffer is connected to the first end of the rear edge double sampling module.

4. A noise reduction circuit for a spectrometer as claimed in claim 3, wherein, The rear edge double sampling module comprises a third switch, a fourth switch, a third capacitor and a fourth capacitor, wherein: The first end of the third switch is connected to the second end of the first buffer, the second end of the third switch is connected to the first end of the third capacitor and the output module respectively; the first end of the fourth switch is connected to the second end of the second buffer, the second end of the fourth switch is connected to the second end of the fourth capacitor and the output module respectively; the second end of the third capacitor is connected to the first end of the fourth capacitor.

5. The noise reduction circuit for a spectrometer of claim 1, wherein, The output module comprises a differential amplifier, wherein: The first input end of the differential amplifier is connected to the second end of the third switch, and the second input end of the differential amplifier is connected to the second end of the fourth switch; The differential amplifier is used for subtracting the front edge signal and the rear edge signal and amplifying the subtraction result.

6. The noise reduction circuit for a spectrometer of claim 1, wherein, The input module comprises a signal input port and an amplifier, wherein: The signal input port is used for accessing the spectrometer charge coupled signal; An input end of the amplifier is connected with the signal input port, and an output end of the amplifier is connected with a first end of the front edge double sampling module.

7. The noise reduction circuit for a spectrometer of claim 1, wherein, The front edge double sampling module is further configured to subtract the noise signal from the spectrometer charge coupled signal to obtain the front edge signal.

8. The noise reduction circuit for a spectrometer of claim 1, wherein, The back edge double sampling module is further configured to subtract the noise signal from the spectrometer charge coupled signal to obtain the back edge signal.

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