Device and method for measuring fluorescence lifetime of rare earth material

Abstract

The invention discloses a fluorescence lifetime measuring device and method for a rare earth material. The device comprises an optical flat plate, an adjustable sample table, an optical fiber tail end focuser, an optical fiber tail end recoverer, a laser, a signal generator, an oscilloscope and a photoelectric detector. The device has the advantages that accurate focusing of exciting light and efficient collection of fluorescence can be achieved, and signal loss is reduced; interference of front and back excitation signals is avoided; the whole fluorescence attenuation process can be accurately captured, and the measurement error is small. The structure is designed in a modular mode, and all parts are convenient to install and adjust; the measurement method has clear steps. The output wavelength of the laser can be flexibly replaced according to the characteristic absorption band of a material to be measured, the wavelength response range of the photoelectric detector covers the characteristic fluorescence wavelength of a mainstream rare earth material, and the photoelectric detector can be adapted to measurement of rare earth materials with nanosecond-level to millisecond-level fluorescence lifetime, including various samples such as rare earth simple substances, rare earth oxides, rare earth doped fluorescent powder and the like. The measurement process does not need a complex data analysis algorithm, and is suitable for rapid detection of batch samples.

Description

Technical Field

[0001] This invention belongs to the field of rare earth material fluorescence characteristic detection technology, and specifically relates to a device and method for measuring the fluorescence lifetime of rare earth materials. Background Technology

[0002] Rare earth materials, due to their unique electronic energy level structure, have wide applications in fields such as luminescence, display, sensing, and lasers. Fluorescence lifetime is a key parameter characterizing the luminescence dynamics of rare earth materials, directly reflecting the excited-state relaxation process, and has important guiding significance for material design and application.

[0003] Currently used methods for measuring fluorescence lifetime include time-correlated single-photon counting and streak camera methods. However, existing devices are often complex in structure, difficult to adjust, and expensive, and have high requirements for optical path alignment and signal synchronization. There is still room for further optimization and improvement of related technical solutions.

[0004] Therefore, it is necessary to provide a fluorescence lifetime measurement device and method that is simple in structure, easy to adjust, low in cost, and has high measurement accuracy to meet the testing needs of rare earth material research and application. Summary of the Invention

[0005] To address the aforementioned problems, the present invention aims to provide a fluorescence lifetime measurement device and method for rare earth materials.

[0006] To achieve the above objectives, the fluorescence lifetime measurement device for rare earth materials provided by the present invention includes an optical plate, an adjustable sample stage, an optical fiber end focuser, an optical fiber end recoverer, a laser, a signal generator, an oscilloscope, and a photodetector.

[0007] The optical plate is horizontally positioned. An adjustable sample stage is mounted on the optical plate, with its top surface used to place the rare earth material sample to be tested. An optical fiber end focuser is positioned above the rare earth material sample, ensuring that the sample is within the output optical path of the fiber optic end focuser. A laser is connected to the fiber optic end focuser via an optical fiber to generate modulated pulsed light, which is then transmitted to the rare earth material sample via the fiber optic end focuser. An optical fiber end recoverer is positioned above and to the side of the adjustable sample stage to collect the fluorescence emitted by the excited rare earth material sample. A photodetector is connected to the optical fiber end recoverer via an optical fiber to convert the collected fluorescence signal into an electrical signal. An oscilloscope is connected to the photodetector via a signal line to display and analyze the electrical signal, thereby obtaining a fluorescence attenuation curve. A signal generator is connected to both the laser and the oscilloscope via signal lines to provide a square wave modulation signal to the laser and trigger synchronous acquisition by the oscilloscope.

[0008] The optical flat plate is equipped with a multi-dimensional adjustable bracket for installing and positioning the fiber optic end focuser and the fiber optic end retractor.

[0009] The adjustable sample stage is a stage with three-dimensional translation adjustment function.

[0010] The signal generator is a high-precision function signal generator.

[0011] The fiber optic end focuser and fiber optic end recoverer are fiber optic collimators / focusers with SMA905 interfaces.

[0012] The optical fiber has a core diameter of 400 μm and is used to conduct modulated pulsed light and collect radiative fluorescence.

[0013] The photodetector is a silicon-based amplified photodetector.

[0014] The oscilloscope used is a digital phosphor oscilloscope.

[0015] The fluorescence lifetime measurement method for rare earth materials provided by this invention includes the following steps performed in sequence:

[0016] Step 1: Based on the expected fluorescence lifetime of the rare earth material to be tested, configure the signal generator to output a square wave modulated signal with a period on the same order of magnitude as the expected fluorescence lifetime and a low-level pulse width not less than the expected fluorescence lifetime.

[0017] Step 2: Place the rare earth material sample to be tested on the adjustable sample stage. Use the multi-dimensional adjustable bracket to adjust the position and angle of the fiber optic end focuser. If necessary, use the adjustable sample stage to focus the modulated pulse light generated by the laser onto the surface of the rare earth material sample to be tested. Adjust the position and angle of the fiber optic end collector so that it can collect the radiation fluorescence generated by the rare earth material sample after it is excited.

[0018] Step 3: Start the signal generator, laser, photodetector, and oscilloscope; the square wave modulation signal output by the signal generator drives the laser to generate periodic modulated pulse light, which is then transmitted to the rare earth material sample under test through the fiber optic end focuser. After that, the radiation fluorescence generated by the rare earth material sample under test after being excited is collected by the fiber optic end collector; the other path is used as a trigger signal input to the oscilloscope; the photodetector converts the collected fluorescence signal into an electrical signal and inputs it into the oscilloscope.

[0019] Step 4: Simultaneously acquire and record the square wave modulation signal and fluorescence decay curve on the oscilloscope, and obtain the time corresponding to the fluorescence intensity decaying from the maximum value to 1 / e based on the fluorescence decay curve, which is taken as the fluorescence lifetime of the rare earth material under test.

[0020] The fluorescence lifetime measurement device and method for rare earth materials provided by this invention have the following beneficial effects:

[0021] 1. High measurement accuracy: Through multi-dimensional adjustment of the adjustable sample stage, focuser, and recovery unit, precise focusing of excitation light and efficient collection of fluorescence can be achieved, reducing signal loss; the square wave parameters of the signal generator are precisely matched with the fluorescence lifetime of rare earth materials, avoiding interference between excitation signals before and after; the high-performance configuration of the photodetector and oscilloscope ensures accurate capture of the entire fluorescence decay process with small measurement error.

[0022] 2. Easy to operate: The device has a modular design, making it easy to install and adjust each component; the measurement method is clear and does not require complicated sample pretreatment. Measurement can be completed with only simple parameter configuration and component adjustment, making it suitable for non-professionals.

[0023] 3. Wide range of applications: The laser output wavelength can be flexibly changed according to the characteristic absorption band of the material to be tested, and the wavelength response range of the photodetector covers the characteristic fluorescence wavelength of mainstream rare earth materials. It can be adapted to the measurement of rare earth materials with fluorescence lifetimes ranging from nanosecond to millisecond, including various samples such as rare earth elements, rare earth oxides, and rare earth doped phosphors.

[0024] 4. High efficiency: The measurement process does not require complex data analysis algorithms, making it suitable for rapid detection of batch samples. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the fluorescence lifetime measurement device for rare earth materials provided by the present invention.

[0026] Figure 2 Er in the example 3+ Fluorescence decay curves of YSZ-doped powder samples. Detailed Implementation

[0027] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0028] like Figure 1 As shown, the fluorescence lifetime measurement device for rare earth materials provided by the present invention includes an optical plate 1, an adjustable sample stage 2, an optical fiber end focuser 6, an optical fiber end retractor 7, a laser 9, a signal generator 10, an oscilloscope 11, and a photodetector 12.

[0029] The optical plate 1 is horizontally positioned; the adjustable sample stage 2 is positioned on the optical plate 1, with its top surface used to place the rare earth material sample 3 to be tested; the fiber optic end focuser 6 is positioned above the rare earth material sample 3 to be tested, ensuring that the rare earth material sample 3 is located in the output optical path of the fiber optic end focuser 6; the laser 9 is connected to the fiber optic end focuser 6 via the fiber optic 8, used to generate modulated pulse light 4 and transmit it to the rare earth material sample 3 via the fiber optic end focuser 6; the fiber optic end collector 7 is positioned above the adjustable sample stage 2, used to collect the radiation fluorescence 5 generated by the rare earth material sample 3 after excitation; the photodetector 12 is connected to the fiber optic end collector 7 via the fiber optic 8, used to convert the collected fluorescence signal into an electrical signal; the oscilloscope 11 is connected to the photodetector 12 via the signal line 13, used to display and analyze the electrical signal, thereby obtaining the fluorescence attenuation curve; the signal generator 10 is connected to the laser 9 and the oscilloscope 11 via the signal line (13), used to provide a square wave modulation signal to the laser 9 and trigger the oscilloscope 11 to acquire synchronously.

[0030] The fluorescence lifetime measurement method for rare earth materials provided by this invention includes the following steps performed in sequence:

[0031] Step 1: Based on the expected fluorescence lifetime of the rare earth material to be tested, configure the signal generator 10 to output a square wave modulated signal with a period on the same order of magnitude as the expected fluorescence lifetime and a low-level pulse width not less than the expected fluorescence lifetime.

[0032] Step 2: Place the rare earth material sample 3 to be tested on the adjustable sample stage 2, and adjust the position and angle of the fiber optic end focuser 6 using the multi-dimensional adjustable bracket. If necessary, use the adjustable sample stage 2 to focus the modulated pulse light generated by the laser 9 onto the surface of the rare earth material sample 3 to be tested; adjust the position and angle of the fiber optic end collector 7 so that it can collect the radiation fluorescence 5 generated after the rare earth material sample 3 is excited.

[0033] Step 3: Start the signal generator 10, laser 9, photodetector 12, and oscilloscope 11; the square wave modulation signal output by the signal generator 10 drives the laser 9 to generate periodic modulated pulse light 4, which is then transmitted to the rare earth material sample 3 to be tested through the fiber optic end focuser 6. After that, the fiber optic end collector 7 collects the radiation fluorescence 5 generated by the rare earth material sample 3 after excitation; the other path is used as a trigger signal input to the oscilloscope 11; the photodetector 12 converts the collected fluorescence signal into an electrical signal and inputs it into the oscilloscope 11;

[0034] Step 4: Simultaneously acquire and record the square wave modulation signal and fluorescence decay curve on oscilloscope 11, and obtain the time corresponding to the fluorescence intensity decaying from the maximum value to 1 / e based on the fluorescence decay curve, as the fluorescence lifetime of the rare earth material under test.

[0035] Example:

[0036] This embodiment uses Er, a typical rare-earth luminescent material. 3+ Taking a doped yttrium oxide stabilized zirconium oxide (YSZ) powder sample as an example, the specific application process of the device and method of the present invention is demonstrated.

[0037] 1. Experimental Materials and Equipment Configuration

[0038] Sample to be tested: Er 3+ YSZ phosphor powder with a doping concentration of 1 mol% was pressed into a flat sheet (approximately 10 mm in diameter and 1 mm in thickness).

[0039] Measuring device: such as Figure 1 The present invention provides fluorescence lifetime measurement for rare earth materials, and the specific parameters of each main component are as follows:

[0040] Optical flat plate 1 and multi-dimensional adjustable bracket: An optical platform with a standard M6 threaded hole array surface is used, and a multi-dimensional adjustable bracket is used to fix the fiber end focuser 6 and the fiber end retractor 7.

[0041] Adjustable sample stage 2: It adopts a stage with precision translation adjustment function of X, Y and Z axes.

[0042] Laser 9: Employs a 532 nm laser with continuously adjustable output power; output wavelength is consistent with Er. 3+ The characteristic absorption bands of the YSZ fluorescent powder are precisely matched, which can effectively excite the sample to produce fluorescence;

[0043] Signal Generator 10: A high-precision function signal generator is selected, with a square wave output frequency range of 1-100000 Hz and an adjustable duty cycle range of 1-99%;

[0044] Fiber optic end focuser 6 and recovery unit 7: Fiber optic collimator / focuser with SMA905 interface.

[0045] Fiber 8: Core diameter 400 μm, used to conduct modulated pulsed light 4 and collect radiative fluorescence 5.

[0046] Photodetector 12: A silicon-based amplified photodetector with a wavelength response range of 350-1100 nm is adopted to meet the measurement requirements.

[0047] Oscilloscope 11: A digital phosphor oscilloscope with a real-time sampling rate of 1 GS / s (per channel), a maximum storage depth of 56 Mpts (per channel), dual channels, and a bandwidth of 100 MHz.

[0048] 2. Measurement Method

[0049] Step 1: Based on the expected fluorescence lifetime of the sample to be tested, configure the signal generator 10 to output a square wave modulation signal with a corresponding period and duty cycle, ensuring that its period matches the expected lifetime and that the low-level time is sufficient to allow the fluorescence to decay sufficiently.

[0050] Step 2: Place the sample to be tested on the adjustable sample stage 2, install and adjust the fiber optic end focuser 6 so that the modulated pulse light 4 emitted by the laser 9 can be accurately focused on the surface of the sample to be tested; install and adjust the fiber optic end collector 7 to a suitable angle above the sample to be tested so as to efficiently collect the radiation fluorescence 5 generated by the sample after it is excited.

[0051] Step 3: Connect the signal generator 10, laser 9, oscilloscope 11 and photodetector 12 with signal cable 13, and start the signal generator 10, laser 9, photodetector 12 and oscilloscope 11 in sequence to observe and collect the square wave modulation signal and fluorescence attenuation curve.

[0052] Step 4: Stabilize the acquisition data on oscilloscope 11 as shown. Figure 2 The fluorescence decay curve shown is analyzed using the measurement function of oscilloscope 11 to determine the time it takes for the fluorescence signal intensity to decay from its peak to 1 / e. This time is the fluorescence lifetime of the sample under test. The reliability of the results can be improved by averaging multiple measurements.

[0053] 3. Results Analysis

[0054] Through the above steps, the YSZ:Er ratio was successfully measured using the device of the present invention. 3+ The fluorescence lifetime of fluorescent powder samples was measured. Fine adjustments to the adjustable sample stage and fiber optic end devices ensured both excitation and fluorescence collection efficiency. A modulated square wave generated by a signal generator, matched to the fluorescence lifetime, effectively isolated interference from adjacent pulses. A high-speed photodetector and oscilloscope accurately captured the microsecond-level fluorescence decay process. The entire measurement process was clear and easy to operate; from sample installation to obtaining the lifetime value, it was typically completed within minutes, demonstrating the effectiveness and practicality of the device and method of this invention in the rapid and accurate measurement of fluorescence lifetime in rare earth materials.

Claims

1. A fluorescence lifetime measurement device for rare earth materials, characterized in that: The device includes an optical flat plate (1), an adjustable sample stage (2), an optical fiber end focuser (6), an optical fiber end retractor (7), a laser (9), a signal generator (10), an oscilloscope (11), and a photodetector (12). The optical plate (1) is horizontally positioned; an adjustable sample stage (2) is positioned on the optical plate (1), with its top surface used to place the rare earth material sample (3) to be tested; an optical fiber end focuser (6) is positioned above the rare earth material sample (3) to be tested, ensuring that the rare earth material sample (3) is located in the output optical path of the optical fiber end focuser (6); a laser (9) is connected to the optical fiber end focuser (6) via an optical fiber (8) to generate modulated pulse light (4) which is then transmitted to the rare earth material sample (3) via the optical fiber end focuser (6); and an optical fiber end retractor (7) is positioned on the adjustable sample stage (2). Above the side, a radiation fluorescence (5) generated by the rare earth material sample (3) after being excited is collected; a photodetector (12) is connected to the fiber end collector (7) through an optical fiber (8) to convert the collected fluorescence signal into an electrical signal; an oscilloscope (11) is connected to the photodetector (12) through a signal line (13) to display and analyze the electrical signal, thereby obtaining the fluorescence decay curve; a signal generator (10) is connected to the laser (9) and the oscilloscope (11) through a signal line (13) to provide a square wave modulation signal to the laser (9) and trigger the oscilloscope (11) to acquire synchronously.

2. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The optical flat plate (1) is provided with a multi-dimensional adjustable bracket for installing and positioning the fiber optic end focuser (6) and the fiber optic end retractor (7).

3. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The adjustable sample stage (2) is a stage with three-dimensional translation adjustment function.

4. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The signal generator (10) is a high-precision function signal generator.

5. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The fiber end focuser (6) and fiber end retractor (7) are fiber collimators / focusers with SMA905 interfaces.

6. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The optical fiber (8) has a core diameter of 400 μm and is used to conduct modulated pulsed light (4) and collect radiative fluorescence (5).

7. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The photodetector (12) is a silicon-based amplified photodetector.

8. The fluorescence lifetime measurement device for rare earth materials according to claim 1, characterized in that: The oscilloscope (11) is a digital phosphor oscilloscope.

9. A method for measuring fluorescence lifetime using the fluorescence lifetime measuring device according to any one of claims 1 to 8, characterized in that: The fluorescence lifetime measurement method includes the following steps performed in sequence: Step 1: Based on the expected fluorescence lifetime of the rare earth material to be tested, configure the signal generator (10) to output a square wave modulated signal with a period on the same order of magnitude as the expected fluorescence lifetime and a low-level pulse width not less than the expected fluorescence lifetime. Step 2: Place the rare earth material sample (3) to be tested on the adjustable sample stage (2), and use the multi-dimensional adjustable bracket to adjust the position and angle of the fiber end focuser (6). If necessary, use the adjustable sample stage (2) to focus the modulated pulse light generated by the laser (9) onto the surface of the rare earth material sample (3) to be tested; adjust the position and angle of the fiber end collector (7) so that it can collect the radiation fluorescence (5) generated by the rare earth material sample (3) after it is excited. Step 3: Start the signal generator (10), laser (9), photodetector (12) and oscilloscope (11); the square wave modulation signal output by the signal generator (10) drives the laser (9) to generate periodic modulated pulse light (4), which is then transmitted to the rare earth material sample (3) to be tested through the fiber end focuser (6). After that, the fiber end collector (7) collects the radiation fluorescence (5) generated by the rare earth material sample (3) after being excited; the other path is used as a trigger signal input to the oscilloscope (11); the photodetector (12) converts the collected fluorescence signal into an electrical signal and inputs it into the oscilloscope (11). Step 4: Simultaneously acquire and record the square wave modulation signal and fluorescence decay curve on the oscilloscope (11), and obtain the time corresponding to the fluorescence intensity decaying from the maximum value to 1 / e according to the fluorescence decay curve, as the fluorescence lifetime of the rare earth material to be tested.

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