A steady-state and transient fluorescence spectroscopy measuring instrument and a measuring method

Abstract

The steady-state and transient fluorescence spectrometer provided by the present invention uses a direct drive torque with high positioning accuracy and high resolution and a circular grating to drive the grating scanning mechanism of the monochromator, which improves the spectral splitting ability of the monochromator and further improves the wavelength positioning accuracy and resolution of the overall instrument. Further, the light for recording spectral information is based on time-correlated single photon counting technology. Since photon information is recorded, the measurement ability for weak signals in the steady-state mode is greatly improved. At the same time, the integration of the steady-state and transient measurement modes is realized on one instrument, which improves the measurement efficiency, reduces the volume of the instrument, and lowers the measurement cost. In addition, by switching the steady-state and transient measurement modes with one key on the upper computer, the convenience of the instrument operation is further improved. The present invention also provides a steady-state and transient fluorescence spectroscopy measurement method.

Description

Technical Field

[0001] The present invention relates to the field of spectral measurement, and particularly relates to a steady-state and transient fluorescence spectrometer and a measurement method thereof. Background Art

[0002] Fluorescence spectrometers can be used for the analysis of the characteristics of substance components and can be applied in many aspects such as chemistry, environment, and biochemistry. Their performance is of great significance for detection accuracy and convenience. A fluorescence spectrometer uses excitation light with a certain intensity to excite a sample. During the transition process of the excited electrons in the sample from the excited state to the ground state, photons are emitted, and an emission spectrum and a luminescence lifetime can be obtained, thereby constructing the relationship between the structure and properties of the substance and further obtaining the characteristics of the substance.

[0003] In existing solutions, a steady-state fluorescence spectrometer measures a sample through methods such as excitation spectrum scanning and fluorescence emission spectrum scanning, and a transient spectrometer measures a sample by obtaining the fluorescence lifetime. An ordinary fluorescence spectrometer cannot obtain steady-state and transient spectra. At the same time, the accuracy and resolution of the monochromator grating scanning mechanism in a fluorescence spectrometer have an important impact on the wavelength accuracy and resolution of the instrument. Therefore, a high-precision and high-resolution grating scanning mechanism can improve the performance of the instrument. Currently, most monochromator grating scanning mechanisms adopt a stepping motor solution for driving, and the accuracy still needs to be improved. If the measurement of steady / transient fluorescence spectra is to be achieved, a method using a dual light source is considered in the market, which greatly increases the volume of the instrument. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a steady-state and transient fluorescence spectrometer and a measurement method thereof. A single scintillating xenon lamp is used as the light source, reducing the volume of the light source of the instrument. Based on time-correlated single-photon counting technology, the output signal of the detector is processed and collected to achieve the acquisition ability of steady-state and transient spectral information of the instrument.

[0005] In a first aspect, embodiments of the present invention provide a steady-state and transient fluorescence spectrometer, including:

[0006] A scintillating xenon lamp, configured to output scintillating light with a preset frequency in the visible light and near-infrared bands as an excitation light source;

[0007] A constant-temperature sample chamber, configured to place a sample to be measured, and the temperature of the constant-temperature sample chamber is adjustable and kept constant;

[0008] A front monochromator, configured to generate single-wavelength excitation light to excite the sample placed therein to generate a fluorescence signal;

[0009] A rear monochromator, configured to detect the fluorescence signal and output a spectral signal carrying wavelength information;

[0010] The first photomultiplier tube is used to detect the spectral signal, convert the spectral signal into a first pulsed electrical signal corresponding to photon information as an end pulse signal, and transmit the pulsed electrical signal to the first constant fraction discriminator;

[0011] The first constant fraction discriminator is used to adjust the first pulsed electrical signal to avoid timing errors caused by signal jitter;

[0012] The second photomultiplier tube is used to detect the output monochromatic light of the pre - monochromator to generate a second pulsed electrical signal corresponding to photons and serve as a start pulse signal;

[0013] The second constant fraction discriminator is used to adjust the second pulsed electrical signal to avoid timing errors caused by signal jitter;

[0014] The time - to - amplitude converter TAC is used to convert the arrival times of the first pulsed electrical signal and the second pulsed electrical signal into corresponding voltage values respectively;

[0015] The buffer is used to buffer all the first data information in the steady - state working mode. The first all data information at least includes corresponding acquisition channel information and photon time information;

[0016] The memory is used to store all the second data information in the transient working mode. The second all data information at least includes channel information and photon distribution information;

[0017] The analog - to - digital converter ADC is used to convert the voltage values in different working modes into digital signals and transmit them to the buffer or the memory;

[0018] The channel register is used to record the information of the acquisition channel and participate in the control of the position of the photon signal in the memory;

[0019] The macro time clock is used to generate the time reference for the time from the start of the experiment to the detection of photons;

[0020] The timing logic circuit is used to generate the timing for controlling the position of the photon signal in the memory in the transient mode;

[0021] The reception controller is used to turn on the first connection switch of the buffer and the macro time clock, and turn on the second connection switch of the memory and the timing logic circuit;

[0022] An industrial control computer is used as the overall controller of the system, storing and displaying the collected data, setting the system parameters, and controlling the switching between the steady-state and transient working modes. In the steady-state working mode, it sends a first instruction to the receiving controller to turn on the switch of the buffer and the first connection switch of the macro time clock. In the transient working mode, it sends a second instruction to the receiving controller to turn on the second connection switch of the memory and the timing logic circuit;

[0023] The flashing xenon lamp is connected to the pre-monochromator. The constant-temperature sample chamber is connected to the thermostat, the pre-monochromator, and the post-monochromator. The temperature controller is connected to the thermostat and the industrial control computer. The first photomultiplier tube is connected to the post-monochromator and the first constant-ratio discriminator. The second photomultiplier tube is connected to the pre-monochromator and the second constant-ratio discriminator. The TAC is connected to the first constant-ratio discriminator, the second constant-ratio discriminator, and the ADC. The buffer and the memory are connected to the ADC, the channel register, the macro time clock, the timing logic circuit, the receiving controller, and the industrial control computer. The channel register is connected to the first constant-ratio discriminator, the second constant-ratio discriminator, the buffer, and the memory. The macro time clock and the timing logic circuit are connected to the first constant-ratio discriminator, the second constant-ratio discriminator, the memory, the buffer, and the receiving controller. The industrial control computer is connected to the buffer, the memory, the macro time clock, the timing logic circuit, and the receiving controller.

[0024] As an optional solution, it further includes:

[0025] A thermostat for adjusting the temperature of the constant-temperature sample chamber and keeping the temperature constant;

[0026] A temperature controller for receiving a third instruction from the industrial control computer to control the thermostat.

[0027] As an optional solution, the pre-monochromator includes an incident slit, a first plane mirror, a second plane mirror, a grating scanning turntable, a grating disposed on the grating scanning turntable, and an exit slit. The flashing light is input from the incident slit, transmitted to the grating through the first plane mirror, diffracted by the grating and then transmitted to the second plane mirror, and exits from the exit slit after being reflected by the second plane mirror. In the steady state mode, the grating scanning turntable drives the grating to rotate. In the transient mode, the grating scanning turntable drives the grating to rotate by a fixed angle.

[0028] As an optional solution, the grating scanning turntable has a grating bracket, and the grating is disposed on the grating bracket.

[0029] As an alternative, the grating is a circular grating.

[0030] As an alternative, the grating scanning turntable includes a circular grating, a power unit, a turntable tabletop, an adapter ring, and a crossed roller bearing ring. The turntable tabletop is mounted on the crossed roller bearing ring, the power unit is connected to the crossed roller bearing ring through the adapter ring, and the circular grating is sleeved on the turntable tabletop.

[0031] As an alternative, the power unit is a direct drive torque motor.

[0032] As an alternative, the turntable tabletop is disc-shaped and has a circular boss at the center, and the circular grating is sleeved on the circular boss.

[0033] As an alternative, the pre-monochromator further includes a housing. The incident slit and the exit slit are symmetrically arranged on both sides of the housing, and the first plane mirror, the second plane mirror, the grating scanning turntable, and the grating are accommodated in the housing.

[0034] In a second aspect, an embodiment of the present invention provides a steady-state and transient fluorescence spectrum measurement method, which is applied to the above-mentioned steady-state and transient fluorescence spectrum measurement instrument. The method includes:

[0035] S1. Sample placement: Place the sample to be measured in the constant-temperature sample chamber;

[0036] S2. Parameter setting: Send the planned set temperature to the temperature controller through the industrial control computer. The temperature controller controls the thermostat to adjust the temperature of the sample chamber until the temperature feedback value remains constant, and set the rotation speed of the pre-monochromator on the industrial control computer;

[0037] S3. Mode selection: Select the steady-state mode or the transient mode. When the steady-state working mode is selected, send a first instruction to the receiving controller through the industrial control computer to open the first connection switch of the buffer and the macro time clock, and keep the connection switch of the memory and the timing logic circuit in the off state; when the transient mode working mode is selected, send a second instruction to the receiving controller through the industrial control computer to open the second connection switch of the memory and the timing logic circuit, and keep the connection switch of the buffer and the macro time clock in the off state;

[0038] S4. Spectral signal acquisition with sample information: When in the steady state mode, the industrial control computer sends acquisition instructions to the receiving controller and the pre-monochromator. The receiving controller turns on the first acquisition switch, and the grating scanning turntable in the pre-monochromator starts to operate. The flashing xenon lamp emits visible light and near-infrared light with a preset frequency of flashing light. After being dispersed by the pre-monochromator, monochromatic light of different wavelengths is output to excite the sample to be measured in the constant temperature sample chamber to generate a fluorescence signal. The post-monochromator conveys the fluorescence signal to the first photomultiplier tube. The first photomultiplier tube converts the fluorescence signal into a first pulsed electrical signal corresponding to photon information. The first constant fraction discriminator adjusts the first pulsed electrical signal to avoid timing errors caused by signal jitter. The time-to-amplitude converter TAC records the micro-time of photons in the signal cycle. The channel register stores the channel information of the detector of the current photon. The macro-time clock records the time from the start of the experiment to photon detection. All the information is transmitted to the buffer and then to the industrial control computer. In the industrial control computer, the photon information per unit time is statistically analyzed to construct an emission spectrum for the analysis of the sample to be measured; When in the transient mode, the industrial control computer sends a second acquisition instruction to the receiving controller and the pre-monochromator. The grating scanning turntable is adjusted to a set angle. The receiving controller turns on the acquisition switch. The monochromatic light of a constant wavelength output by the pre-monochromator excites the sample to be measured to generate a fluorescence signal. The fluorescence signal is transmitted through the pre-monochromator to the second multiplier tube and converted into a second pulsed electrical signal. After the second pulsed electrical signal is processed by the second constant fraction discriminator, it is transmitted to the TAC. The second photomultiplier converts the monochromatic light output by the pre-monochromator into a second pulsed electrical signal as a reference signal. The second constant fraction discriminator processes the reference signal and transmits it to the TAC. The TAC converts the time between the signal source pulse and the reference signal pulse into a voltage value. The channel register and the timing logic circuit control the position of the voltage value in the memory. Different voltage values correspond to different positions. After constructing a photon distribution, it is stored and displayed in the industrial control computer;

[0039] S5. Measurement end: After the acquisition is completed, the industrial control computer sends a reset instruction to the grating scanning turntable, and the grating scanning turntable performs a reset movement.

[0040] The steady-state and transient fluorescence spectrometer provided by the present invention uses a direct drive torque with high positioning accuracy and high resolution and a circular grating to drive the grating scanning mechanism of the monochromator, improving the spectral splitting ability of the monochromator and further enhancing the wavelength positioning accuracy and resolution of the overall instrument. Further, based on the time-correlated single photon counting technology for recording light of spectral information, since photon information is recorded, the measurement ability for weak signals in the steady-state mode is greatly improved. At the same time, the integration of the steady-state and transient measurement modes is achieved on one instrument, improving the measurement efficiency, reducing the instrument volume, and lowering the measurement cost. In addition, by switching the steady-state and transient measurement modes with one key on the host computer, the convenience of the instrument operation is further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 FIG. is a structural block diagram of a steady-state and transient fluorescence spectrometer provided in an embodiment of the present invention;

[0042] Figure 2 FIG. is a schematic structural diagram of a pre-monochromator in a steady-state and transient fluorescence spectrometer provided in an embodiment of the present invention;

[0043] Figure 3 FIG. is a schematic structural diagram of a grating scanning turntable in a steady-state and transient fluorescence spectrometer provided in an embodiment of the present invention;

[0044] Figure 4 FIG. is a schematic structural diagram of a grating scanning turntable in a steady-state and transient fluorescence spectrometer provided in an embodiment of the present invention;

[0045] Figure 5 FIG. is a schematic flow chart of a steady-state and transient fluorescence measurement method provided in an embodiment of the present invention.

[0046] REFERENCE SIGNS:

[0047] Scintillating xenon lamp 1, pre-monochromator 2, constant temperature sample chamber 3, thermostat 4, temperature controller 5, post-monochromator 6, first photomultiplier tube 7, second photomultiplier tube 8, first constant fraction discriminator 9, second constant fraction discriminator 10, channel register 11, TAC 12, macro time clock 13, timing logic circuit 14, ADC 15, buffer 16, memory 17, receiving controller 18, industrial control computer 19, grating 20, grating scanning turntable 21, housing 22, entrance slit 23, exit slit 24, first plane mirror 25, second plane mirror 26, turntable tabletop 27, power unit 28, adapter ring 29, crossed roller bearing 30. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0048] To enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0049] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order other than that shown or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0050] Combined with Figure 1 As shown, a steady-state and transient fluorescence spectrometer is provided in an embodiment of the present invention, including:

[0051] A scintillation xenon lamp 1, configured to output scintillation light with a preset frequency in the visible light and near-infrared bands as an excitation light source;

[0052] A constant-temperature sample chamber 3, configured to place a sample to be measured, and the temperature of the constant-temperature sample chamber is adjustable and kept constant;

[0053] A pre-monochromator 2, configured to generate excitation light with a single wavelength to excite the sample to be measured to generate a fluorescence signal;

[0054] A post-monochromator 6, configured to detect the fluorescence signal and output a spectral signal carrying wavelength information;

[0055] A first photomultiplier tube 7, configured to detect the spectral signal, convert the spectral signal into a first pulse electrical signal corresponding to photon information as an end pulse signal, and transmit the pulse electrical signal to a first constant fraction discriminator 9;

[0056] The first constant fraction discriminator 9 is configured to adjust the first pulse electrical signal to avoid timing errors caused by signal jitter;

[0057] A second photomultiplier tube 8, configured to detect the output monochromatic light of the pre-monochromator 2 to generate a second pulse electrical signal corresponding to photons as a start pulse signal;

[0058] A second constant ratio discriminator 10 for adjusting the second pulsed electrical signal to avoid timing errors caused by signal jitter;

[0059] A time - amplitude converter TAC12 for converting the arrival times of the first pulsed electrical signal and the second pulsed electrical signal into corresponding voltage values respectively;

[0060] A buffer 16 for caching all the first data information in the steady - state operating mode, where the first all data information at least includes corresponding acquisition channel information and photon time information;

[0061] A memory 17 for storing all the second data information in the transient operating mode, where the second all data information at least includes channel information and photon distribution information;

[0062] An analog - to - digital converter ADC15 for converting the voltage values in different operating modes into digital signals and transmitting them to the buffer 16 or the memory 17;

[0063] A channel register 11 for recording the information of the acquisition channel and simultaneously participating in the control of the position of the photon signal in the memory 17;

[0064] A macro - time clock 13 for generating the time reference for the time from the start of the experiment to the detection of photons;

[0065] A timing logic circuit 14 for generating timing to control the position of the photon signal in the memory 17 in the transient mode;

[0066] A receiving controller 18 for opening the first connection switch of the buffer 16 and the macro - time clock 13, and opening the second connection switch of the memory 17 and the timing logic circuit 14;

[0067] An industrial control computer 19 for serving as the overall control of the system, storing and displaying the acquired data, setting system parameters, controlling the switching between the steady - state and transient operating modes. In the steady - state operating mode, it sends a first instruction to the receiving controller 18 to open the switch of the buffer 16 and the first connection switch of the macro - time clock 13. In the transient operating mode, it sends a second instruction to the receiving controller 18 to open the second connection switch of the memory 17 and the timing logic circuit 14;

[0068] The flashing xenon lamp is connected to the pre-monochromator 2. The constant-temperature sample chamber is connected to the thermostat, the pre-monochromator 2, and the post-monochromator 6. The temperature controller is connected to the thermostat and the industrial control computer. The first photomultiplier tube 7 is connected to the post-monochromator 6 and the first constant-ratio discriminator 9. The second photomultiplier tube 8 is connected to the pre-monochromator 2 and the second constant-ratio discriminator 10. The TAC 12 is connected to the first constant-ratio discriminator 9, the second constant-ratio discriminator 10, and the ADC 15. The buffer 16 and the memory 17 are connected to the ADC 15, the channel register 11, the macro time clock 13, the timing logic circuit 14, the receiving controller 18, and the industrial control computer. The channel register 11 is connected to the first constant-ratio discriminator 9, the second constant-ratio discriminator 10, the buffer 16, and the memory 17. The macro time clock 13 and the timing logic circuit 14 are connected to the first constant-ratio discriminator 9, the second constant-ratio discriminator 10, the memory 17, the buffer 16, and the receiving controller 18. The industrial control computer is connected to the buffer 16, the memory 17, the macro time clock 13, the timing logic circuit 14, and the receiving controller 18.

[0069] In some embodiments, it further includes:

[0070] A thermostat 4 for adjusting the temperature of the constant-temperature sample chamber and keeping the temperature constant. The temperature controller is placed inside the constant-temperature sample chamber;

[0071] A temperature controller 5 for receiving the third instruction from the industrial control computer to control the thermostat. The temperature controller is respectively connected to the industrial control computer and the thermostat.

[0072] Combined with Figure 2 As shown, in some embodiments, the pre-monochromator 2 includes an incident slit 23, a first plane mirror 25, a second plane mirror 26, a grating scanning turntable 21, a grating 20 disposed on the grating scanning turntable 21, and an exit slit 24. The flashing light is input from the incident slit 23, transmitted to the grating 20 through the first plane mirror 25. After diffraction by the grating 20, it is transmitted to the second plane mirror 26 and exits from the exit slit 24 after reflection by the second plane mirror 26. In the steady state mode, the grating scanning turntable 21 drives the grating 20 to rotate. In the transient mode, the grating scanning turntable 21 drives the grating 20 to rotate by a fixed angle.

[0073] Combined with Figure 3 As shown, in some embodiments, the grating scanning turntable 21 has a grating bracket, and the grating is disposed on the grating bracket. The grating 20 can be a circular grating, and no limitation is made thereto.

[0074] Combined Figure 4 As shown, in some embodiments, the grating bracket can be the turntable table 27. The grating scanning turntable 21 includes a grating 20, a power unit 28, a turntable table 27, an adapter ring 29, and a crossed roller bearing 30. The turntable table is used to drive the circular grating to rotate. The circular grating is used to record the actual movement and feedback the information to the controller, compare it with the actual movement situation, and perform movement adjustment to reduce errors. The repeat positioning accuracy of the power unit 28 is better than 0.1″, and high-precision driving of the grating scanning turntable 21 is performed. The turntable table is installed on the crossed roller bearing 30, the power unit 28 is connected to the crossed roller bearing 30 through the adapter ring 29, and the circular grating is sleeved on the turntable table.

[0075] In some embodiments, the power unit 28 can be a direct drive torque motor with a repeat positioning accuracy better than 0.1″. It should be noted that those of ordinary skill in the art can make flexible selections and are not limited thereto.

[0076] In some embodiments, the turntable table is disk-shaped and has a circular boss at the center, and the circular grating is sleeved on the circular boss.

[0077] In some embodiments, the pre-monochromator 2 further includes a housing 22. The entrance slit 23 and the exit slit 24 are symmetrically arranged on both sides of the housing 22. The first plane mirror 25, the second plane mirror 26, the grating scanning turntable 21, and the grating are accommodated in the housing 22.

[0078] The steady-state and transient fluorescence spectrometer provided by the present invention uses a direct drive torque with high positioning accuracy and high resolution and a circular grating to drive the grating scanning mechanism of the monochromator, improving the spectral splitting ability of the monochromator, further improving the wavelength positioning accuracy and resolution of the overall instrument. Further, based on the time-correlated single photon counting technology for recording light of spectral information, since photon information is recorded, the measurement ability of weak signals in the steady state mode is greatly improved. At the same time, the integration of the steady-state and transient measurement modes is realized on one instrument, improving the measurement efficiency, reducing the volume of the instrument, and lowering the measurement cost. In addition, by switching the steady-state and transient measurement modes with one key on the upper computer, the convenience of the instrument operation is further improved.

[0079] Correspondingly, the present invention also provides a steady-state and transient fluorescence spectroscopy measurement method, which is applied to the above-mentioned steady-state and transient fluorescence spectrometer. The method includes:

[0080] S1. Sample placement: Place the sample to be measured in the constant temperature sample chamber;

[0081] S2. Set parameters: Send the planned set temperature to the temperature controller through the industrial control computer. The temperature controller controls the thermostat to adjust the temperature of the sample chamber until the temperature feedback value remains constant. Set the rotation speed of the pre-monochromator 2 on the industrial control computer;

[0082] S3. Mode selection: Select the steady-state mode or the transient mode. When the steady-state working mode is selected, send a first instruction to the receiving controller 18 through the industrial control computer, turn on the first connection switch of the buffer 16 and the macro time clock 13, and keep the connection switch between the memory 17 and the timing logic circuit 14 in the off state; when the transient mode working mode is selected, send a second instruction to the receiving controller 18 through the industrial control computer, turn on the second connection switch between the memory 17 and the timing logic circuit 14, and keep the connection switch between the buffer 16 and the macro time clock 13 in the off state;

[0083] S4. Spectral signal acquisition with sample information: When in the steady state mode, the industrial control computer sends acquisition instructions to the receiving controller 18 and the pre-monochromator 2. The receiving controller 18 turns on the first acquisition switch, and the grating scanning turntable 21 in the pre-monochromator 2 starts to operate. The flashing xenon lamp emits visible light and near-infrared light with a preset frequency of flashing light. After being spectroscopically analyzed by the pre-monochromator 2, monochromatic light of different wavelengths is output to excite the sample to be measured in the constant temperature sample chamber to generate a fluorescence signal. The post-monochromator 6 conveys the fluorescence signal to the first photomultiplier tube 7. The first photomultiplier tube 7 converts the fluorescence signal into a first pulsed electrical signal corresponding to photon information. The first constant fraction discriminator adjusts the first pulsed electrical signal to avoid timing errors caused by signal jitter. The time-to-amplitude converter TAC12 records the micro-time of the photon in the signal period. The channel register 11 stores the channel information of the detector of the current photon. The macro-time clock 13 records the time from the start of the experiment to the photon detection. All the information is transmitted to the buffer 16 and then to the industrial control computer. In the industrial control computer, the photon information is statistically analyzed per unit time to construct an emission spectrum for the analysis of the sample to be measured; when in the transient mode, the industrial control computer sends a second acquisition instruction to the receiving controller 18 and the pre-monochromator 2. The grating scanning turntable 21 is adjusted to a set angle. The receiving controller 18 turns on the acquisition switch. The monochromatic light with a constant wavelength output by the pre-monochromator 2 excites the sample to be measured to generate a fluorescence signal. The fluorescence signal is transmitted through the pre-monochromator 2 to the second multiplier tube and converted into a second pulsed electrical signal. After the second constant fraction discriminator 10 processes the second pulsed electrical signal, it is transmitted to the TAC12. The second photomultiplier converts the monochromatic light output by the pre-monochromator 2 into a second pulsed electrical signal as a reference signal. The second constant fraction discriminator 10 processes the reference signal and transmits it to the TAC12. The TAC12 converts the time between the signal source pulse and the reference signal pulse into a voltage value. The channel register 11 and the timing logic circuit 14 control the position of the voltage value in the memory 17. Different voltage values correspond to different positions. After constructing a photon distribution, it is stored and displayed in the industrial control computer;

[0084] S5. Measurement end: After the acquisition is completed, the industrial control computer sends a reset instruction to the grating scanning turntable 21, and the grating scanning turntable 21 performs a reset movement.

[0085] Combined with Figure 5 As shown, in the embodiment of the present invention, another steady-state and transient fluorescence spectrum measurement method is provided, which is applied to the above-mentioned steady-state and transient fluorescence spectrum measuring instrument. The method includes:

[0086] S501. Sample placement: Place the sample to be measured in the sample chamber.

[0087] S502, Parameter Setting: The operator sends the temperature to be set to the temperature controller through the industrial control computer. Then, the temperature controller controls the thermostat to adjust the temperature of the sample chamber until the temperature feedback value remains constant. After that, the rotation speed of the grating scanning mechanism of the monochromator is set on the industrial control computer.

[0088] S503, Mode Selection: Select the steady-state mode and transient mode according to the desired mode. When selecting the steady-state working mode, the operator sends an instruction to the receiving controller through the industrial control computer to turn on the connection switch between the buffer and the macro time clock, and ensure that the connection switch between the memory and the sequential logic circuit is in the off state; when selecting the transient mode working mode, the operator sends an instruction to the receiving controller through the industrial control computer to turn on the connection switch between the memory and the sequential logic circuit, and ensure that the connection switch between the buffer and the macro time clock is in the off state.

[0089] S504, Acquisition of Spectral Signals Carrying Sample Information: In the steady-state mode, the operator sends an acquisition instruction to the receiving controller and the pre-high-precision monochromator through the industrial control computer. The receiving controller turns on the acquisition switch, and the grating scanning mechanism in the pre-high-precision monochromator starts to operate. The flashing xenon lamp emits a wide-band spectrum in the visible and near-infrared bands. After being split by the pre-high-precision monochromator, monochromatic light of different wavelengths is output to excite the sample in the constant-temperature sample chamber to generate fluorescence. The post-monochromator delivers the fluorescence to the photomultiplier tube. The photomultiplier tube converts the fluorescence signal into a pulsed electrical signal corresponding to photons. The constant-fraction discriminator preliminarily processes the signal. Then, the TAC records the micro-time of the photons in the signal period, and at the same time, the channel register stores the channel information of the detector of the current photon. The macro time clock records the time from the start of the experiment to the photon detection. All the information is transmitted to the buffer, and then to the industrial control computer. Finally, the statistics of photon information per unit time are performed on the industrial control computer to construct the emission spectrum for sample analysis; in the transient mode, the operator sends an acquisition instruction to the receiving controller and the pre-high-precision monochromator through the industrial control computer. The grating scanning mechanism is adjusted to the set angle. The receiving controller turns on the acquisition switch. The monochromatic light of a constant wavelength output by the monochromator is used to excite the sample. The fluorescence is transmitted to the second multiplier tube through the post-monochromator and converted into a pulsed electrical signal. After being processed by the first constant-fraction discriminator, the signal is transmitted to the TAC. The second photomultiplier converts the monochromatic light output by the monochromator into a pulsed electrical signal as a reference signal. The second constant-fraction discriminator processes the reference signal and transmits it to the TAC. The TAC converts the time between the signal source pulse and the reference signal pulse into a voltage value. The channel register and the sequential logic circuit control the position of this voltage value in the memory. Different voltage values correspond to different positions, thus constructing a photon distribution, which is then stored and displayed on the industrial control computer.

[0090] S505, Measurement End: After the acquisition is completed, the operator sends a reset command to the grating scanning mechanism of the monochromator through the industrial control computer. The grating scanning mechanism performs a reset movement, and it is judged whether it is necessary to perform the acquisition work again. If so, steps S503 and S504 are repeated. Otherwise, this measurement work is ended.

[0091] In the steady-state and transient fluorescence spectrum measurement method provided in the embodiment of the present invention, a single flashing xenon lamp is used as the light source, reducing the light source volume of the instrument. The grating scanning mechanism in the monochromator is driven with high precision and high resolution by a direct drive torque motor and a circular grating, improving the spectral splitting ability of the monochromator. Based on the time-correlated single photon counting technology, the output signal of the detector is processed and acquired, realizing the steady-state and transient spectral information acquisition ability of the instrument.

[0092] It should be understood that various forms of processes shown above can be used, reordering, adding or deleting steps. For example, the steps described in the present disclosure can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solutions disclosed in the present invention can be achieved. No limitation is made herein.

[0093] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A steady-state and transient fluorescence spectroscopy measuring instrument, characterized in that, it includes: A scintillating xenon lamp, which is used to output scintillating light with a preset frequency in the visible light and near-infrared bands as an excitation light source; A constant-temperature sample chamber, which is used to place the sample to be measured, and the temperature of the constant-temperature sample chamber is adjustable and kept constant; A front monochromator, which is used to generate excitation light of a single wavelength to excite the sample placed therein to generate a fluorescence signal; A rear monochromator, which is used to detect the fluorescence signal and output a spectral signal carrying wavelength information; A first photomultiplier tube, which is used to detect the spectral signal, convert the spectral signal into a first pulse electrical signal corresponding to photon information as an end pulse signal, and transmit the pulse electrical signal to a first constant fraction discriminator; The first constant fraction discriminator is used to adjust the first pulse electrical signal to avoid timing errors caused by signal jitter; A second photomultiplier tube, which is used to detect the output monochromatic light of the front monochromator to generate a second pulse electrical signal corresponding to photons and serve as a start pulse signal; A second constant fraction discriminator, which is used to adjust the second pulse electrical signal to avoid timing errors caused by signal jitter; A time-to-amplitude converter TAC, which is used to convert the arrival times of the first pulse electrical signal and the second pulse electrical signal into corresponding voltage values respectively; A buffer, which is used to cache all the first data information in the steady-state working mode, and the first all data information at least includes corresponding acquisition channel information and photon time information; A memory, which is used to store all the second data information in the transient working mode, and the second all data information at least includes channel information and photon distribution information; An analog-to-digital converter ADC, which is used to convert the voltage values in different working modes into digital signals and transmit them to the buffer or the memory; A channel register, which is used to record the information of the acquisition channel and participate in the control of the position of the photon signal in the memory; A macro time clock, which is used to generate a time reference for the time when the photon is detected from the start of the experiment; A timing logic circuit, which is used to generate timing to control the position of the photon signal in the memory in the transient mode; A reception controller, which is used to open the first connection switch of the buffer and the macro time clock, and open the second connection switch of the memory and the timing logic circuit; An industrial control computer, which is used as the overall control of the system, stores and displays the acquired data, sets system parameters, controls the switching between the steady-state and transient working modes. In the steady-state working mode, it sends a first instruction to the reception controller to open the switch of the buffer and the first connection switch of the macro time clock. In the transient working mode, it sends a second instruction to the reception controller to open the second connection switch of the memory and the timing logic circuit; A thermostat, which is used to adjust the temperature of the constant-temperature sample chamber and keep the temperature constant; A temperature controller, which is used to receive the third instruction of the industrial control computer to control the thermostat; The flashing xenon lamp is connected to the pre - monochromator. The constant - temperature sample chamber is connected to the thermostat, the pre - monochromator, and the post - monochromator. The temperature controller is connected to the thermostat and the industrial control computer. The first photomultiplier tube is connected to the post - monochromator and the first constant - ratio discriminator. The second photomultiplier tube is connected to the pre - monochromator and the second constant - ratio discriminator. The TAC is connected to the first constant - ratio discriminator, the second constant - ratio discriminator, and the ADC. The buffer and the memory are connected to the ADC, the channel register, the macro time clock, the timing logic circuit, the receiving controller, and the industrial control computer. The channel register is connected to the first constant - ratio discriminator, the second constant - ratio discriminator, the buffer, and the memory. The macro time clock and the timing logic circuit are connected to the first constant - ratio discriminator, the second constant - ratio discriminator, the memory, the buffer, and the receiving controller. The industrial control computer is connected to the buffer, the memory, the macro time clock, the timing logic circuit, and the receiving controller.

2. The steady - state and transient fluorescence spectrometer according to claim 1, characterized in that, the pre - monochromator includes an incident slit, a first plane mirror, a second plane mirror, a grating scanning turntable, a grating disposed on the grating scanning turntable, and an exit slit. The flashing light is input from the incident slit, transmitted to the grating through the first plane mirror, diffracted by the grating and then transmitted to the second plane mirror, and exits from the exit slit after being reflected by the second plane mirror. In the steady - state mode, the grating scanning turntable drives the grating to rotate. In the transient mode, the grating scanning turntable drives the grating to rotate by a fixed angle.

3. The steady - state and transient fluorescence spectrometer according to claim 2, characterized in that, the grating scanning turntable has a grating bracket, and the grating is disposed on the grating bracket.

4. The steady - state and transient fluorescence spectrometer according to claim 2, characterized in that, the grating is a circular grating.

5. The steady - state and transient fluorescence spectrometer according to claim 2, characterized in that, the grating scanning turntable includes a circular grating, a power unit, a turntable surface, an adapter ring, and a crossed roller bearing ring. The turntable surface is mounted on the crossed roller bearing ring. The power unit is connected to the crossed roller bearing ring through the adapter ring. The circular grating is sleeved on the turntable surface.

6. The steady - state and transient fluorescence spectrometer according to claim 5, characterized in that, the power unit is a direct - drive torque motor.

7. The steady - state and transient fluorescence spectrometer according to claim 5 or 6, characterized in that, the turntable surface is disc - shaped and has a circular boss at the center. The circular grating is sleeved on the circular boss.

8. The steady - state and transient fluorescence spectrometer according to claim 2, characterized in that, The pre - monochromator further includes a housing, the incident slit and the exit slit are symmetrically arranged on both sides of the housing, and the first plane mirror, the second plane mirror, the grating scanning turntable, and the grating are accommodated in the housing.

9. A method for measuring steady - state and transient fluorescence spectra, characterized in that, applied to the steady - state and transient fluorescence spectrometer according to any one of claims 1 to 8, the method includes: S1. Sample placement: Place the sample to be measured in the constant - temperature sample chamber; S2. Parameter setting: Send the planned set temperature to the temperature controller through the industrial control computer, and the temperature controller controls the thermostat to adjust the temperature of the sample chamber until the temperature feedback value remains constant, and set the rotation speed of the pre - monochromator on the industrial control computer; S3. Mode selection: Select the steady - state mode or the transient mode. When the steady - state working mode is selected, send a first instruction to the receiving controller through the industrial control computer, turn on the first connection switch of the buffer and the macro time clock, and keep the connection switch between the memory and the timing logic circuit in the off state; when the transient mode working mode is selected, send a second instruction to the receiving controller through the industrial control computer, turn on the second connection switch of the memory and the timing logic circuit, and keep the connection switch between the buffer and the macro time clock in the off state; S4. Spectral signal acquisition with sample information: When in the steady state mode, the industrial control computer sends acquisition instructions to the receiving controller and the pre-monochromator. The receiving controller turns on the first acquisition switch, and the grating scanning turntable in the pre-monochromator starts to operate. The flashing xenon lamp emits visible light and near-infrared light with a preset frequency of flashing light. After being dispersed by the pre-monochromator, monochromatic light of different wavelengths is output to excite the sample to be measured in the constant temperature sample chamber to generate fluorescence signals. The post-monochromator conveys the fluorescence signals to the first photomultiplier tube. The first photomultiplier tube converts the fluorescence signals into first pulse electrical signals corresponding to photon information. The first constant fraction discriminator adjusts the first pulse electrical signals to avoid timing errors caused by signal jitter. The time-to-amplitude converter TAC records the micro-time of photons in the signal cycle. The channel register stores the channel information of the detector of the current photon. The macro-time clock records the time from the start of the experiment to photon detection. All the information is transmitted to the buffer and then to the industrial control computer. In the industrial control computer, the photon information per unit time is statistically analyzed to construct the emission spectrum for the analysis of the sample to be measured; When in the transient mode, the industrial control computer sends a second acquisition instruction to the receiving controller and the pre-monochromator. The grating scanning turntable is adjusted to a set angle. The receiving controller turns on the acquisition switch. The monochromatic light of a constant wavelength output by the pre-monochromator excites the sample to be measured to generate fluorescence signals. The fluorescence signals are transmitted through the pre-monochromator to the second multiplier tube and converted into second pulse electrical signals. After signal processing of the second pulse electrical signals by the second constant fraction discriminator, they are transmitted to the TAC. The second photomultiplier converts the monochromatic light output by the pre-monochromator into a second pulse electrical signal as a reference signal. The second constant fraction discriminator processes the reference signal and transmits it to the TAC. The TAC converts the time between the signal source pulse and the reference signal pulse into a voltage value. The channel register and the timing logic circuit control the position of the voltage value in the memory. Different voltage values correspond to different positions. After constructing a photon distribution, it is stored and displayed in the industrial control computer; S5. End of measurement: After the acquisition is completed, the industrial control computer sends a reset instruction to the grating scanning turntable, and the grating scanning turntable performs a reset movement.

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