A fast detection method for photon detection efficiency of silicon photomultiplier tubes

Abstract

The invention relates to the field of weak light detection methods, and discloses a rapid detection method for photon detection efficiency of a silicon photomultiplier tube, comprising the following steps: S1, supplying power to the silicon photomultiplier tube by a voltage-stabilized power supply, and measuring the dark count rate; S2, attenuating a bromine tungsten lamp light source through a neutral attenuation plate, and then filtering through a monochromator and a monochromator filter, and irradiating the silicon photomultiplier tube through a port of an integrating sphere; S3, calculating an array list of total count rates of the silicon photomultiplier tube changing with wavelength through a computer; S4, irradiating the bromine tungsten lamp light source through a monochromator and a monochromator filter, and then irradiating the PIN standard detector through another port of an integrating sphere, and using a precision source meter to measure the photocurrent of the PIN standard detector changing with wavelength. Only a relatively common test instrument in a laboratory needs to be used for measurement, which effectively reduces the measurement cost and alleviates the problems of high test system price and high measurement cost in the existing method.

Description

Technical Field

[0001] The invention relates to the technical field of weak light detection methods, and in particular to a rapid detection method for photon detection efficiency of a silicon photomultiplier tube. Background Art

[0002] The so-called photon detection efficiency (PDE) of a silicon photomultiplier (SiPM) refers to the percentage of the number of photons detected by the SiPM within a certain period of time to the number of photons incident on the surface of the SiPM.

[0003] There are three main methods for measuring the photon detection efficiency of silicon photomultiplier tubes:

[0004] The first method is the photocurrent measurement method, which uses attenuated continuous light to generate monochromatic light to illuminate the silicon photomultiplier tube, control the photon flux, and measure the photocurrent of the silicon photomultiplier tube and the calibrated PIN detector. The ratio of the two is the photon detection efficiency.

[0005] The second method is based on Poisson's theory. Under weak pulsed light, the number of photons detected by the detector is Poisson distributed. The average number of photons detected by the detector is measured by this theory, and then the number of incident photons is calibrated. The ratio of the two is the photon detection efficiency. This method can eliminate the influence of crosstalk effect on photon detection efficiency.

[0006] The third method is the pulse photon counting method, which uses a light-emitting diode (LED), optical fiber, attenuator and monochromator to process light and illuminate the silicon photomultiplier tube. After the signal is amplified, the pulse amplitude is analyzed by a multi-channel analyzer (MCA) or an analog to digital converter (ADC). The pulse height distribution (PHD) of the silicon photomultiplier tube is used to calculate the number of photoelectrons and calibrate the number of incident photons. The ratio of the two is used to obtain the photon detection efficiency.

[0007] The first measurement method cannot eliminate the influence of optical crosstalk and after-pulse effect by measuring photocurrent, so the photon detection efficiency of silicon photomultiplier tube is overestimated. At the same time, when the leakage current of silicon photomultiplier tube is large, the photocurrent may be submerged, so the method of total current minus leakage current to measure photon detection efficiency is inaccurate.

[0008] The second measurement method requires short pulse light for light intensity calibration, which is inaccurate and leads to a low value of photon detection efficiency. At the same time, measuring the change curve of photon detection efficiency with wavelength requires replacing different wavelength LEDs or laser heads, which is inconvenient and costly.

[0009] The third measurement method cannot eliminate the influence of optical crosstalk on photon detection efficiency, which will cause an overestimation of the photon detection efficiency measurement results. Summary of the invention

[0010] In view of the deficiencies in the prior art, the present invention provides a method for rapidly detecting the photon detection efficiency of a silicon photomultiplier tube, which solves the problems of high cost, low versatility and low detection efficiency in the prior art methods for measuring the photon detection efficiency of silicon photomultiplier tubes.

[0011] To achieve the above objectives, the present invention is implemented by the following technical scheme: A method for rapidly detecting the photon detection efficiency of a silicon photomultiplier tube comprises the following steps:

[0012] S1, power the silicon photomultiplier tube with a regulated power supply, input the avalanche signal output by the silicon photomultiplier tube into a general digital oscilloscope, and measure the dark count rate;

[0013] S2, after the bromine tungsten light source is attenuated by a neutral attenuation plate, it is split by a monochromator and filtered by a monochromator filter, and then irradiated to a silicon photomultiplier tube through the port of an integrating sphere;

[0014] S3, using a computer to calculate the array list of the total count rate of the silicon photomultiplier tube as it changes with wavelength;

[0015] S4, after the bromine tungsten lamp light source is split by a monochromator and filtered by a monochromator filter, it is irradiated to a PIN standard detector through another port of an integrating sphere, and a precision source meter is used to measure the variation of the photocurrent of the PIN standard detector with wavelength;

[0016] S5. Calculate the number of photons irradiated on the silicon photomultiplier tube according to the ratio of the light receiving area and the attenuation multiple;

[0017] S6. The net pulse count rate is obtained by subtracting the dark count rate from the total count rate. The net pulse count rate is divided by the number of photons irradiated on the silicon photomultiplier tube to calculate the photon detection efficiency of the silicon photomultiplier tube.

[0018] Preferably, the optical processing method of the broadband light source includes attenuation by a neutral attenuator, spectrometry by a monochromator and filtering by a monochromator filter, and the processed light is irradiated to the silicon photomultiplier tube through the port of the integrating sphere.

[0019] Preferably, in step S4, the integrating sphere comprises two ports, one port is used to irradiate the silicon photomultiplier tube, and the other port is used to irradiate the PIN standard detector.

[0020] Preferably, the total count rate of the silicon photomultiplier tube is calculated by a digital oscilloscope, and the effective static pulse count rate is obtained by subtracting the dark count rate.

[0021] Preferably, the number of photons N irradiated on the PIN standard detector in step S5 is PIN Obtained through the following algorithm:

[0022]

[0023] Where I(λ) is the array of photocurrents of the PIN standard detector that vary with wavelength, R is the photoresponsivity, h is Planck's constant, and c is the speed of light in a vacuum.

[0024] Preferably, the number of photons N irradiated on the silicon photomultiplier tube in step S5 is iN Calculated by the following formula:

[0025]

[0026] In the formula, A SiPM and A PIN are the total photosensitive areas of the silicon photomultiplier tube and the PIN standard detector, respectively, and M is the attenuation multiple of the neutral attenuator.

[0027] Preferably, the photon count rate R detected by the silicon photomultiplier tube in step S5 is det (λ) and the total pulse count rate R total The relationship between (λ) is:

[0028] R det (λ)=R total (λ)-DCR;

[0029] The formula for photon detection efficiency is:

[0030] PDE(λ)=R det (λ) / N in (λ)×100%

[0031] The rapid detection system of silicon photomultiplier tube photon detection efficiency includes:

[0032] A silicon photomultiplier tube, used to receive the irradiated light and output an avalanche signal;

[0033] Monochromator, used for spectroscopic processing;

[0034] Precision source meter for measuring the photocurrent of standard detectors;

[0035] A general-purpose digital oscilloscope for receiving avalanche signals and calculating dark count rate and total count rate;

[0036] A regulated power supply for supplying power to the silicon photomultiplier tube;

[0037] Computer, used to control the entire detection system and perform data processing;

[0038] Bromine tungsten lamp light source, used to provide broadband light source;

[0039] Monochromator filter, used for filtering light;

[0040] Neutral attenuation sheet, used to control the intensity of the light source;

[0041] Integrating sphere, used to evenly distribute light and illuminate the light to the silicon photomultiplier tube and PIN standard detector respectively;

[0042] PIN standard detector, used to receive light and perform calibration.

[0043] Preferably, the general digital oscilloscope includes but is not limited to a counter or a frequency meter with a high-speed pulse counting function.

[0044] Preferably, the silicon photomultiplier tube includes but is not limited to a pin-type packaged SiPM and a chip-packaged SiPM.

[0045] Working principle: The silicon photomultiplier tube is biased by a voltage regulator, and the signal output is passed to the analog channel CH1 of a general digital oscilloscope to record the signal and directly obtain the average dark count rate. The bromine tungsten light source is attenuated by a neutral attenuation plate with a known attenuation multiple, and then irradiated to the silicon photomultiplier tube through the integrating sphere port after being split by a monochromator and filtered by a monochromator filter. The program on the computer can directly calculate the array list of its total count rate changing with wavelength, and subtract the dark count rate to obtain the static pulse count rate. There is no need to replace the silicon photomultiplier tube. The bromine tungsten light source is split by a monochromator and filtered by a monochromator filter, and then irradiated to the PIN standard detector through the integrating sphere port. The program on the computer can directly obtain the number of photons irradiated on the PIN standard detector, and calculate the number of photons irradiated on the silicon photomultiplier tube by the ratio of the light receiving area and the attenuation multiple. Finally, the photon detection efficiency can be obtained through the above known data.

[0046] The present invention provides a method for quickly detecting the photon detection efficiency of a silicon photomultiplier tube, which has the following beneficial effects:

[0047] 1. The present invention only needs to use relatively common test instruments in the laboratory for measurement, which effectively reduces the measurement cost and alleviates the problems of high price of the test system and high measurement cost in the existing method.

[0048] 2. The detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention improves the detection efficiency, has strong versatility and a wide range of applications.

[0049] 3. The rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention eliminates the optical crosstalk effect and the after-pulse below 0.5pe, making the measurement result more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a schematic diagram of the working state of the measurement system involved in the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention;

[0051] Figure 2 It is a flow chart of a method for rapid detection of photon detection efficiency of a silicon photomultiplier tube of the present invention;

[0052] Figure 3 The present invention is a graph showing the variation trend of the photon detection efficiency of a silicon photomultiplier tube with the bias voltage, which is measured by using the rapid detection method for the photon detection efficiency of the silicon photomultiplier tube of the present invention.

[0053] Among them, 1. Silicon photomultiplier tube; 2. Monochromator; 3. Precision source meter; 4. General digital oscilloscope; 5. Regulated power supply; 6. Computer; 7. Bromine tungsten lamp light source; 8. Monochromator filter; 9. Neutral attenuation film; 10. Integrating sphere; 11. PIN standard detector. DETAILED DESCRIPTION

[0054] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] The measuring device used in the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention has a structure as follows: Figure 1 As shown, it includes a silicon photomultiplier tube 1, the silicon photomultiplier tube 1 is externally connected to a voltage-stabilized power supply 5, the silicon photomultiplier tube 1 is connected to a monochromator 2, a precision source meter 3, a universal digital oscilloscope 4 and a computer 6 in sequence; the monochromator 2 is connected to a bromine tungsten lamp light source 7, a monochromator filter 8, a neutral attenuation plate 9, an integrating sphere 10, and a PIN standard detector 11; the computer 6 is embedded with a program containing the above algorithm, the program can directly calculate an array list of total count rate varying with wavelength, and obtain a static pulse count rate by subtracting a dark count rate; finally, after calibration, the number of photons irradiated on the device is calculated to obtain the photon detection efficiency at different wavelengths, thereby realizing a rapid detection method for the photon detection efficiency of a silicon photomultiplier tube of the present invention.

[0056] The flowchart of the method for rapid detection of photon detection efficiency of silicon photomultiplier tube of the present invention is as follows: Figure 2As shown, the specific implementation steps are as follows:

[0057] S1, powered by a voltage stabilizer 5, the avalanche signal output by the silicon photomultiplier tube 1 is input into a general digital oscilloscope 4, the bias voltage is adjusted, the DCR under different bias voltages is obtained, and the average value is calculated;

[0058] The silicon photomultiplier tube 1 adopts the MPPCS13360-1325CS silicon photomultiplier tube;

[0059] The general digital oscilloscope 4 is a SDS1202X-C digital oscilloscope; the general digital oscilloscope 4 can be used to record and transmit the avalanche signal waveform data and the average dark count rate output by the silicon photomultiplier tube 1;

[0060] The voltage-stabilized power supply 5 is a SPD3303X precision voltage-stabilized power supply, which is used to provide power supply.

[0061] S2. After step 1, the bromine tungsten lamp light source 7 is attenuated by a neutral attenuation plate 9 with a known attenuation multiple, and then irradiated onto the silicon photomultiplier tube 1 through port 1 of the integrating sphere 10 after being split by the monochromator 2 and filtered by the monochromator filter 8.

[0062] S3, using computer 6 to directly calculate the array list R of the total count rate changing with wavelength total (λ), the computer was set to scan the wavelength from 300 to 1000 nm with a step size of 5 nm.

[0063] S4, the bromine tungsten lamp light source 7 is irradiated onto the PIN standard detector 11 through the port 2 of the integrating sphere 10 after being split by the monochromator 2 and filtered by the monochromator filter 8.

[0064] S5. The variation of the photocurrent of the PIN standard detector 11 with the wavelength I(λ) can be obtained through the precision source meter 3. Dividing it by the light response R is the light power irradiated on the PIN standard detector 11, which is converted into the number of photons irradiated on the PIN standard detector 11, and finally the number of photons irradiated on the silicon photomultiplier tube 1 is calculated.

[0065] S5.1, the number of photons N irradiating the PIN standard detector 11 within 1s PIN Obtained through the following algorithm:

[0066]

[0067] Wherein, I(λ) is an array of the photocurrents of the PIN standard detector 11 that vary with wavelength, R is the photoresponsivity, h is the Planck constant, and c is the speed of light in a vacuum.

[0068] S5.2. Using N PINWhen converting the number of photons irradiated on the silicon photomultiplier tube 1, the ratio of the light receiving area and the attenuation factor must be taken into account. The number of photons irradiated on the silicon photomultiplier tube 1 is:

[0069]

[0070] In the formula, A SiPM and A PIN are the total photosensitive area of ​​the silicon photomultiplier tube 1 and the PIN standard detector 11. M is the attenuation multiple of the neutral attenuator.

[0071] S5.3, photon count rate R detected by silicon photomultiplier tube 1 det (λ) and the total pulse count rate R total The relationship between (λ) is:

[0072] R det (λ)=R total (λ)-DCR;

[0073] S5.4, through S5.2, S5.3, we can quickly get the formula of photon detection efficiency:

[0074] PDE(λ)=R det (λ) / N in (λ)×100%;

[0075] S6. Process the data and calculate the photon detection efficiency of the silicon photomultiplier tube for light of different wavelengths under the same over-bias voltage according to the formula.

[0076] The principle of the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention is as follows:

[0077] When a stable continuous light is attenuated to a certain extent, photons will be transmitted randomly and discretely one by one. If this light is irradiated on a silicon photomultiplier tube, and the increase in the count rate of the avalanche pulse caused is statistically different from the dark count of the silicon photomultiplier tube, the PDE data can be quantitatively measured based on the light response count of the silicon photomultiplier tube.

[0078] First, use a PIN standard detector to calibrate the number of photons irradiated on the device. The specific algorithm for the number of photons irradiated on the PIN standard detector is as follows:

[0079]

[0080] In formula (1), N PIN is the number of photons irradiating the PIN standard detector per unit time (1s), h is Planck's constant, c is the speed of light in vacuum, and R is the light response.

[0081] Considering the ratio of the light receiving area and the attenuation multiple, the number of photons irradiated on the silicon photomultiplier tube can be calculated. The specific algorithm is as follows:

[0082]

[0083] In formula (2), A SiPM and A PIN are the total photosensitive areas of SiPM and PIN standard detectors respectively. M is the attenuation factor of the neutral attenuator.

[0084] The static pulse count rate can be measured using the total pulse count rate R total (λ) minus the average dark count rate. The specific algorithm is as follows:

[0085] R det (λ)=R total (λ)-DCR (3);

[0086] The expression of photon detection efficiency of silicon photomultiplier tube can be easily obtained by using equations (2) and (3):

[0087] PDE(λ)=R det (λ) / N in (λ)×100% (4);

[0088] The accuracy verification of the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention is as follows:

[0089] like Figure 3 As shown, it can be seen that the measured relationship between the photon detection efficiency of the silicon photomultiplier tube and the wavelength is basically consistent with the result provided in the manual. Under the recommended bias voltage (56-69V) in the detector manual, the photon detection efficiency measured by the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention is (27.5%), which is also basically consistent with the nominal value (26%) in the detector manual. This shows that the rapid detection method of the photon detection efficiency of the silicon photomultiplier tube of the present invention is correct and reliable.

[0090] like Figure 1As shown, the silicon photomultiplier tube 1 used in this embodiment is MPPCS13360-1325CS (produced by Hamamatsu Co., Ltd., Japan); the monochromator 2 is Omni-λ300 (produced by Zolix Co., Ltd., China); the precision source meter 3 is B2901 (100fA, 21V, produced by Keysight Co., Ltd., USA); the general digital oscilloscope 4 is SDS1202X-C digital oscilloscope (200MHzbandwidth, 1GSa / s, produced by SIGLENT Co., Ltd., China); the regulated power supply 5 is SPD2203X precision regulated power supply (produced by SIGLENT Co., Ltd., China); and the integrating sphere 10 is IS-150-38 (produced by Zolix Co., Ltd., China).

[0091] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A rapid detection method for photon detection efficiency of silicon photomultiplier tubes, characterized in that: The following steps are involved: S1, supplying power to the silicon photomultiplier tube (1) from a voltage stabilizer (5), inputting the avalanche signal output by the silicon photomultiplier tube (1) into a general digital oscilloscope (4), and measuring the dark count rate; S2, after the bromine tungsten lamp light source (7) is attenuated by a neutral attenuation plate (9), the light is split by a monochromator (2) and filtered by a monochromator filter (8), and then irradiated to a silicon photomultiplier tube (1) through a port of an integrating sphere (10); S3, calculating, by means of a computer (6), an array list showing how the total count rate of the silicon photomultiplier tube (1) changes with wavelength; S4, after the bromine tungsten lamp light source (7) is split by the monochromator (2) and filtered by the monochromator filter (8), it is irradiated to the PIN standard detector (11) through the other port of the integrating sphere (10), and the variation of the photocurrent of the PIN standard detector (11) with the wavelength is measured by the precision source meter (3); S5, calculating the number of photons irradiated on the silicon photomultiplier tube (1) according to the ratio of the light receiving area and the attenuation multiple; S6. The net pulse count rate is obtained by subtracting the dark count rate from the total count rate. The net pulse count rate is divided by the number of photons irradiated on the silicon photomultiplier tube to calculate the photon detection efficiency of the silicon photomultiplier tube (1).

2. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: The optical processing method of the broadband light source includes attenuation by a neutral attenuation plate (9), light splitting by a monochromator (2) and filtering by a monochromator filter (8), and the processed light is irradiated to a silicon photomultiplier tube (1) through a port of an integrating sphere (10).

3. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: In step S4, the integrating sphere (10) comprises two ports, one port is used to irradiate the silicon photomultiplier tube (1), and the other port is used to irradiate the PIN standard detector (11).

4. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: The total count rate of the silicon photomultiplier tube (1) is calculated by a digital oscilloscope (4), and the effective static pulse count rate is obtained by subtracting the dark count rate.

5. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: The number of photons N irradiated on the PIN standard detector (11) in step S5 is PIN Obtained through the following algorithm: Where I(λ) is the array of photocurrent responses of the PIN standard detector (11) that vary with wavelength, R is the photoresponsivity, h is Planck's constant, and c is the speed of light in vacuum.

6. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: The number of photons N irradiated on the silicon photomultiplier tube (1) in step S5 is iN Calculated by the following formula: In the formula, A SiPM and A PIN are the total photosensitive area of ​​the silicon photomultiplier tube (1) and the PIN standard detector (11), respectively, and M is the attenuation multiple of the neutral attenuation plate.

7. The method for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 1, characterized in that: The photon count rate R detected by the silicon photomultiplier tube (1) in step S5 is det (λ) and the total pulse count rate R total The relationship between (λ) is: R det (λ)=R total (λ)-DCR; The formula for photon detection efficiency is: PDE(λ)=R det (λ) / N in (λ)×100%.

8. A rapid detection device for photon detection efficiency of a silicon photomultiplier tube, according to the rapid detection method for photon detection efficiency of a silicon photomultiplier tube according to claims 1-7, characterized in that: include: A silicon photomultiplier tube (1), used for receiving the irradiated light and outputting an avalanche signal; Monochromator (2), used for spectroscopic processing; Precision source meter (3) for measuring the photocurrent of a standard detector; A general digital oscilloscope (4) for receiving the avalanche signal and measuring the dark count rate and the total count rate; A voltage-stabilized power supply (5), used for supplying power to the silicon photomultiplier tube; A computer (6), used for controlling the entire detection system and performing data processing; A bromine tungsten lamp light source (7) is used to provide a broadband light source; A monochromator filter (8) for filtering light; A neutral attenuation sheet (9) for controlling the intensity of the light source; An integrating sphere (10), used for evenly distributing light and irradiating the light to the silicon photomultiplier tube and the PIN standard detector respectively; The PIN standard detector (11) is used to receive light and perform calibration.

9. The device for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 8, characterized in that: The universal digital oscilloscope (4) includes but is not limited to a counter or a frequency meter with a high-speed pulse counting function.

10. The device for rapid detection of photon detection efficiency of silicon photomultiplier tube according to claim 8, characterized in that: The silicon photomultiplier tube (1) includes but is not limited to a pin-type packaged SiPM and a chip-packaged SiPM.

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