CN109959637B - Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle - Google Patents
Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle Download PDFInfo
- Publication number
- CN109959637B CN109959637B CN201910270548.0A CN201910270548A CN109959637B CN 109959637 B CN109959637 B CN 109959637B CN 201910270548 A CN201910270548 A CN 201910270548A CN 109959637 B CN109959637 B CN 109959637B
- Authority
- CN
- China
- Prior art keywords
- laser
- signal
- light intensity
- current signal
- medicine bottle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/27—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
- G01N21/274—Calibration, base line adjustment, drift correction
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/59—Transmissivity
Landscapes
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Analytical Chemistry (AREA)
- Pathology (AREA)
- Immunology (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- General Physics & Mathematics (AREA)
- General Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mathematical Physics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Theoretical Computer Science (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses an etalon effect inhibiting method and device for detecting residual oxygen amount of a glass medicine bottle, the method obtains main transmission light intensity and transmission light intensity after twice reflection after laser penetrates the glass medicine bottle, and converts the main transmission light intensity and the transmission light intensity after twice reflection into a first current signal, obtains transmission light intensity after once reflection and transmission light intensity after three times reflection when the laser penetrates the glass medicine bottle, and converts the transmission light intensity into a second current signal, obtains output current according to the first current signal and the second current signal, extracts a second harmonic current signal of the output current, and obtains oxygen concentration according to the second harmonic current signal, solves the technical problem that the residual oxygen amount is low due to optical noise brought to the second harmonic by light beam interference generated by the wall of the glass medicine bottle in the prior art, and can inhibit the etalon effect from the root source by eliminating the noise in the second harmonic from a signal detection part, the oxygen concentration detection precision and the stability of the system are greatly improved.
Description
Technical Field
The invention relates to the technical field of gas detection, in particular to a method and a device for detecting gas in a glass medicine bottle based on a wavelength modulation technology.
Background
The existing off-line gas content detector on the market mainly depends on traditional methods such as a chemical colorimetric method, a gas chromatography method, an electrochemical method, a magnetic oxygen analysis method and the like, the traditional analysis detection systems need complex pretreatment and most of the traditional analysis detection systems are destructive, a sampling pretreatment system is not needed in a wavelength modulation technology, non-invasive in-situ rapid measurement of gas detection can be realized, and the off-line gas content detector has good adaptability.
However, in the process of detecting the concentration of residual oxygen in the packaged glass medicine bottle, laser emitted by the laser is affected by the etalon effect, so that mutual interference between transmission light intensities is caused, and finally, the transmission light intensity is distorted, so that the detection of a second harmonic signal is affected. In recent papers and patent descriptions, most of the methods for detecting the residual oxygen concentration of the packaged glass medicine bottle use various subsequent filtering algorithms to eliminate noise in second harmonic, and the second harmonic distortion caused by the etalon effect is caused by light beam interference generated by the inner wall of the glass bottle, so that a detection method capable of better inhibiting the etalon effect is found from a signal detection part.
Disclosure of Invention
The invention provides an etalon effect inhibition method and device for detecting residual oxygen of a glass medicine bottle, and solves the technical problem that in the prior art, the residual oxygen detection precision is low due to optical noise caused by second harmonic wave caused by light beam interference generated by the wall of the glass medicine bottle.
In order to solve the technical problem, the etalon effect inhibition method for detecting the residual oxygen content of the glass medicine bottle provided by the invention comprises the following steps:
acquiring main transmission light intensity after laser penetrates through the glass medicine bottle and transmission light intensity after the laser is reflected twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal;
acquiring the transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser is reflected for three times, and converting the transmission light intensity into a second current signal;
obtaining an output current according to the first current signal and the second current signal;
extracting a second harmonic current signal of the output current;
and obtaining the oxygen concentration according to the second harmonic current signal.
Further, the method for obtaining the main transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser is reflected twice and converting the main transmission light intensity and the transmission light intensity into a first current signal further comprises the following steps:
adjusting the incident angle of the laser so that the incident angle satisfies L/lambda epsilon M, wherein M is a positive integer, L is the optical path of the laser penetrating through the glass medicine bottle, lambda is the laser wavelength, and L is d/cos theta2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
Further, obtaining the output current according to the first current signal and the second current signal comprises:
eliminating the refractive index factor of the second current signal to obtain a third current signal;
and subtracting the third current signal from the first current signal to obtain an output current, wherein the calculation formula of the output current is as follows:
i*(t)＝i0(t)αNL(1+r)2
wherein i*(t) is the output current, i0(t) is the injection current of the laser, alpha is the absorption coefficient, N is the oxygen concentration, L is the optical path of the laser penetrating the glass vial, and r is the reflectivity.
Further, the calculation formula for obtaining the oxygen concentration according to the second harmonic current signal is as follows:
wherein, N is the concentration of oxygen,
for the second harmonic current signal peak value, i0(t) is the injection current of the laser, L is the optical path of the laser penetrating the glass vial, r is the reflectivity, S2Is the second harmonic term coefficient.
The invention provides an etalon effect suppression device for detecting residual oxygen amount of a glass medicine bottle, which comprises:
the device comprises a light source module and a signal processing module connected with the light source module, wherein the light source module is used for emitting laser to irradiate and penetrate through a glass medicine bottle;
the signal processing module comprises a signal generating part, a first photoelectric detector, a second photoelectric detector, a signal operation part connected with the first photoelectric detector and the second photoelectric detector, a signal demodulation part connected with the signal operation part, and a harmonic analysis part connected with the signal demodulation part, wherein:
the signal generation part is used for driving the light source module and outputting a high-frequency signal double-frequency signal to the signal demodulation part;
the first photoelectric detector is used for acquiring the main transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser is reflected twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal;
the second photoelectric detector is used for acquiring the transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser penetrates through the glass medicine bottle for one time and the transmission light intensity after the laser penetrates through the glass medicine bottle for three times, and converting the transmission light intensity into a second current signal;
a signal operation section for obtaining an output current from the first current signal and the second current signal;
a signal demodulation section for extracting a second harmonic current signal of the output current;
and the harmonic analysis part is used for obtaining the oxygen concentration according to the second harmonic current signal.
Further, the apparatus further comprises:
an incident angle adjusting module for adjusting the incident angle of the laser, so that the incident angle satisfies L/λ ∈ M, where M is a positive integer, where L is the optical path of the laser penetrating through the glass vial, λ is the laser wavelength, and L ═ d/cos θ2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
Further, the light source module includes a laser and a laser control part for controlling the laser, wherein,
the laser control part comprises a current control part and a temperature control part, wherein the current control part is used for controlling the working current of the laser, and the temperature control part is used for controlling the working temperature of the laser.
Further, the first photoelectric detector and the second photoelectric detector are respectively positioned on two sides of the glass medicine bottle, and the second photoelectric detector and the laser are positioned on the same side.
Further, the signal output by the signal generating part for driving the light source module is a combined signal of a low-frequency sawtooth wave and a high-frequency sine wave.
Further, the center wavelength of the laser is 760 nm.
Compared with the prior art, the invention has the advantages that:
the invention provides an etalon effect inhibition method and device for detecting residual oxygen amount of a glass medicine bottle, which obtains main transmission light intensity after laser penetrates through the glass medicine bottle and transmission light intensity after twice reflection, converts the main transmission light intensity and the transmission light intensity into a first current signal, obtains transmission light intensity after once reflection and transmission light intensity after three times reflection when the laser penetrates through the glass medicine bottle, converts the transmission light intensity into a second current signal, obtains output current according to the first current signal and the second current signal, extracts a second harmonic current signal of the output current and obtains oxygen concentration according to the second harmonic current signal, solves the technical problem that the detection precision of the residual oxygen amount is low due to optical noise brought to second harmonic by light beam interference generated by the wall of the glass medicine bottle in the prior art, can inhibit the etalon effect from the root by eliminating noise in the second harmonic from a signal detection part, the oxygen concentration detection precision and the stability of the system are greatly improved.
Drawings
FIG. 1 is a flowchart of an etalon effect suppression method for detecting residual oxygen content of a glass vial according to a first embodiment of the present invention;
FIG. 2 is a flowchart of an etalon effect suppression method for detecting residual oxygen content of a glass vial according to a second embodiment of the present invention;
FIG. 3 is a schematic diagram of glass vial etalon effect generation;
FIG. 4 is a graph of a second harmonic waveform after being affected by etalon effects;
FIG. 5 is a waveform diagram of the second harmonic after eliminating the influence of the etalon effect by the etalon effect suppression method for detecting the residual oxygen content of the glass vial according to the second embodiment of the present invention;
fig. 6 is a block diagram showing the configuration of an etalon effect suppression device for detecting the residual oxygen content of a glass vial according to an embodiment of the present invention.
Reference numerals:
10. a light source module; 20. a signal processing module; 101. a laser control section; 102. a laser; 201. a signal generating section; 202. a first photodetector; 203. a second photodetector; 204. a signal operation section; 205. a signal demodulating section; 206. a harmonic analysis section; 1011. a current control section; 1012. a temperature control section.
Detailed Description
In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below.
The embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways as defined and covered by the claims.
Example one
Referring to fig. 1, an etalon effect suppression method for detecting residual oxygen in a glass vial according to an embodiment of the present invention includes:
step S101, obtaining main transmission light intensity after laser penetrates through a glass medicine bottle and transmission light intensity after laser reflects twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal;
step S102, obtaining the transmission light intensity after once reflection and the transmission light intensity after three times reflection when the laser penetrates through the glass medicine bottle, and converting the transmission light intensity into a second current signal;
step S103, obtaining output current according to the first current signal and the second current signal;
step S104, extracting a second harmonic current signal of the output current;
and step S105, obtaining the oxygen concentration according to the second harmonic current signal.
The etalon effect inhibition method for detecting the residual oxygen amount of the glass medicine bottle provided by the embodiment of the invention obtains the main transmission light intensity after laser penetrates through the glass medicine bottle and the transmission light intensity after twice reflection, converts the main transmission light intensity and the transmission light intensity into the first current signal, obtains the transmission light intensity after once reflection and the transmission light intensity after three times reflection when the laser penetrates through the glass medicine bottle, converts the transmission light intensity into the second current signal, obtains the output current according to the first current signal and the second current signal, extracts the second harmonic current signal of the output current and obtains the oxygen concentration according to the second harmonic current signal, solves the technical problem that the residual oxygen amount detection precision is low due to the optical noise caused by the second harmonic caused by the light beam interference generated by the wall of the glass medicine bottle in the prior art, can inhibit the etalon effect fundamentally by eliminating the noise in the second harmonic from the signal detection part, the oxygen concentration detection precision and the stability of the system are greatly improved.
Example two
Referring to fig. 2, an etalon effect suppression method for detecting residual oxygen in a glass vial according to a second embodiment of the present invention includes:
step S201, adjusting the incident angle of the laser so that the incident angle satisfies L/λ ∈ M, where M is a positive integer, where L is the optical path of the laser penetrating through the glass vial, λ is the laser wavelength, and L ═ d/cos θ2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
Specifically, the etalon effect generation schematic of the glass vial of the present embodiment is shown in fig. 3. Due to the change of the angle theta of the incident light1The angle of refraction θ can be varied2Then the optical length L is d/cos theta2Also changes when the incident angle theta1Adjusted to a suitable value and the center wavelength of the laser emission is the center wavelength of the oxygen absorption, so that L/λ is a positive integer M.
Step S202, obtaining the main transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser reflects twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal.
Specifically, in FIG. 3, the main transmitted light intensity I1(t) is:
I1(t)＝I0T2exp[-αNL] (1)
wherein, I0Is the laser incident light intensity, T is the transmittance, alpha is the absorption coefficient, and N is the oxygen concentrationAnd L is the optical path of the laser penetrating the glass medicine bottle.
Specifically, the transmittance is
Where Δ δ is the phase difference between the two beams and r represents the reflectivity. Since the initial phases of the two beams are the same, then
Where λ is the wavelength of the laser, x1Is the main transmission optical path, x2Is the secondary transmitted light path. As can be seen from FIG. 3, the optical path difference (x)1-x2) Is 2L.
in FIG. 3, the transmitted light intensity I after two reflections2(t) is:
I2(t)＝I0(t)T2r2exp[-3αNL] (2)
according to the principle of superposition of interference fringes1(t) and I2(t) the superimposed transmitted light intensity I (t) is:
in the case of weak absorption of the gas in the vial, i.e., α NL < <1, exp [ - α NL ] developed in the form of a first order Taylor series, which can be approximated to 1- α NL, the transmitted light intensity I (t) is:
since the current i (t) is linear to the light intensity I (t), the transmitted light intensity I (t) is converted to obtain a first current signal i (t) as:
i(t)＝i0(t)T2+i0(t)T2r2+2i0(t)T2rcos(△δ)-i0(t)T2αNL[1+3r2+4rcos(△δ)](5)
wherein i (t) is a first current signal i0(T) is the injection current of the laser, T is the transmittance, r is the reflectance, Delta delta is the phase difference between the main transmitted light intensity and the transmitted light intensity after two reflections, and
alpha is absorption coefficient, N is oxygen concentration, L is optical path of laser penetrating glass medicine bottle, and x1Is the main transmission optical path, x2Is the optical path of the secondary transmitted light, and λ is the laser wavelength.
Step S203, obtaining the transmission light intensity after the laser is reflected once and the transmission light intensity after the laser is reflected three times when the laser penetrates through the glass medicine bottle, and converting the transmission light intensity into a second current signal.
Specifically, in FIG. 3, the transmitted light intensity I after one reflection1' (t) is:
I1'(t)＝I0(t)T2rexp(-2αNL) (6)
in FIG. 3, the transmitted light intensity I after three reflections2' (t) is:
I'2(t)＝I0(t)T2r3exp(-4αNL) (7)
according to the principle of superposition of interference fringes1' (t) and I2'(t) the superimposed transmitted light intensity I' (t) is:
the second current signal I '(t) after the transmitted light intensity I' (t) is converted is:
i'(t)＝r(i0(t)T2+i0(t)T2r2+2i0(t)T2rCOS(△δ)-2i0(t)T2αNL(1+2r2+3rCOS(△δ))) (9)
and step S204, eliminating the refractive index factor of the second current signal to obtain a third current signal.
Specifically, the present embodiment divides the second current signal i' (t) by r to obtain a third current signal i "(t) as:
in step S205, the third current signal and the first current signal are subtracted to obtain an output current.
Specifically, the current signal i' (t) with the refractive index factor r removed is subtracted from i (t) to subtract the interference signal, and the output current i (10) of the signal operation part is obtained by using the formula (5) to subtract the formula (10)*(t)：
In step S201, when the adjustment angle of incidence satisfies L/λ ∈ M, where M is a positive integer, Δ δ can be made to be 4M π. Then, cos (4 pi L/λ) ═ 1, and the calculation formula for obtaining the output current is:
i*(t)＝i0(t)αNL(1+r)2 (12)
wherein i*(t) is the output current, i0(t) is the injection current of the laser, alpha is the absorption coefficient, N is the oxygen concentration, L is the optical path of the laser penetrating the glass vial, and r is the reflectivity.
In step S206, a second harmonic current signal of the output current is extracted.
Specifically, the output current i (t) obtained according to step S205*After multiplying the high-frequency signal frequency-doubled signal output by the signal generating part, the output is easily extractedCurrent i (t)*Second harmonic current signal of
Comprises the following steps:
where ω is the second harmonic current signal frequency, S2Is the second harmonic term coefficient.
And step S207, acquiring the oxygen concentration according to the second harmonic current signal.
In particular, based on second harmonic current signal peaks
The oxygen concentration N can be calculated back as:
wherein, N is the concentration of oxygen,
for the second harmonic current signal peak value, i0(t) is the injection current of the laser, L is the optical path of the laser penetrating the glass vial, r is the reflectivity, S2Is the second harmonic term coefficient.
From equation (14), it can be derived that the interference term is eliminated, i.e., the concentration N is independent of the interference term, and L, r, S2Is a constant number i0(t) is the injection current of the laser, i.e. the concentration N and L, r, S2、i0(t)
And the oxygen concentration can be accurately calculated in a linear relation.
Fig. 4 is a waveform diagram of the second harmonic wave after being affected by the etalon effect, fig. 5 is a waveform diagram of the second harmonic wave after being affected by the etalon effect is eliminated by the etalon effect suppression method for detecting residual oxygen amount of the glass vial according to the second embodiment of the present invention, and it is obvious from fig. 4 and fig. 5 that: a large amount of optical noise is superposed on the second harmonic waveform affected by the etalon effect, when the peak value of the optical noise is used for carrying out concentration inversion, inversion errors are caused certainly, the second harmonic waveform graph after the etalon effect is eliminated is quite smooth, jitter is basically avoided at the peak point, and smoothness of a second harmonic signal and inversion accuracy of oxygen concentration can be improved. Therefore, the embodiment of the invention eliminates the noise in the second harmonic from the signal detection part, can fundamentally inhibit the etalon effect, and greatly improves the oxygen concentration detection precision and the stability of the system.
Specifically, on one hand, in the embodiment, by detecting the transmission light intensity at two sides of the glass medicine bottle to obtain the first current signal and the second current signal, and performing subtraction operation on the third current signal obtained by eliminating the refractive index factor of the second current signal and the first current signal, the refractive index factor can be eliminated, the subtraction of interference signals can be realized, and the noise in the second harmonic wave can be greatly eliminated, so that the etalon effect of the glass medicine bottle residual oxygen amount detection system can be effectively inhibited; on the other hand, according to the phase difference relation among the multiple beams, the embodiment of the invention adjusts the proper incidence angle to achieve the purpose of eliminating the interference item; and finally, the smoothness of the second harmonic signal is used as an optimization index, so that the etalon effect can be effectively inhibited, and the inversion accuracy of the oxygen concentration is improved.
Referring to fig. 6, an etalon effect suppression device for detecting residual oxygen in a glass vial according to an embodiment of the present invention includes:
the device comprises a light source module 10 and a signal processing module 20 connected with the light source module 10, wherein the light source module 10 is used for emitting laser irradiation and penetrating through a glass medicine bottle;
the signal processing module 20 includes a signal generating section 201, a first photodetector 202, a second photodetector 203, a signal operation section 204 connected to the first photodetector 202 and the second photodetector 203, a signal demodulation section 205 connected to the signal operation section 204, and a harmonic analysis section 206 connected to the signal demodulation section 205, wherein:
a signal generating part 201 for driving the light source module 10 and outputting a high frequency signal doubled frequency signal to the signal demodulating part 205;
a first photoelectric detector 202 for obtaining the main transmission light intensity after the laser penetrates the glass medicine bottle and the transmission light intensity after the laser reflects twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal,
a second photoelectric detector 203 for obtaining the transmission light intensity after once reflection and the transmission light intensity after three times reflection when the laser penetrates the glass medicine bottle, and converting into a second current signal,
a signal operation section 204 for obtaining an output current based on the first current signal and the second current signal,
a signal demodulating section 205 for extracting a second harmonic current signal of the output current,
and a harmonic analysis section 206 for obtaining the oxygen concentration from the second harmonic current signal.
Optionally, the apparatus further comprises:
an incident angle adjusting module for adjusting the incident angle of the laser, so that the incident angle satisfies L/λ ∈ M, where M is a positive integer, where L is the optical path of the laser penetrating through the glass vial, λ is the laser wavelength, and L ═ d/cos θ2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
Alternatively, the first photodetector 202 and the second photodetector 203 are located on both sides of the glass vial, respectively, and the second photodetector 203 is located on the same side as the laser 102.
The light source module 10 optionally includes a laser 102 and a laser control section 101 for controlling the laser 102, wherein,
the laser control section 101 includes a current control section 1011 for controlling the operating current of the laser 102 and a temperature control section 1012 for controlling the operating temperature of the laser 102.
Alternatively, the signal for driving the light source module 10 output by the signal generating part 201 is a combined signal of a low frequency sawtooth wave and a high frequency sine wave.
Optionally, the center wavelength of the laser 102 is 760 nm.
In the etalon effect suppression device for detecting the residual oxygen amount of the glass medicine bottle, provided by the embodiment of the invention, the DDS in the FPGA chip in the signal generation part 201 is synthesized into the low-frequency sawtooth wave and the high-frequency sine wave, the low-frequency sawtooth wave and the high-frequency sine wave are used for being sent to the laser control part 101 to drive the laser 102, and the corresponding injection current is i0(t), the current control part 1011 of the light source module 10 precisely controls the operating current of the laser 102, and the temperature control part 1012 of the light source module 10 is used to control the operating temperature of the laser 102 to be constant; the modulation signal current-tunes the DFB laser 102 with a center wavelength of 760nm to produce a signal having an intensity I0(t) an output light intensity; meanwhile, the light frequency v (t) of the laser can cover the absorption line of oxygen, the transmitted light intensity I (t) absorbed by the oxygen in the glass medicine bottle is converted into an electric signal I (t) by the first photoelectric detector 202 through free space transmission, and the transmitted light intensity I '(t) absorbed by the oxygen in the glass medicine bottle is converted into an electric signal I' (t) by the second photoelectric detector 203; converted into an electric signal i by a signal operation section 204*(t), the signal demodulating section 205 acquires the second harmonic i2f(t) output, harmonic analysis section 206 passes through i2f(t) peak value i2fmaxAnd inverting the oxygen concentration N in the medicine bottle to be detected so as to further realize the online content of the oxygen content.
The specific process of realizing the detection of the residual oxygen content of the glass medicine bottle by the etalon effect inhibition device for detecting the residual oxygen content of the glass medicine bottle provided by the embodiment of the invention comprises the following steps:
step 1, a schematic diagram of etalon effect generation of a glass medicine bottle is shown in fig. 3, wherein a laser 102 and a second photoelectric detector 203 are arranged on one side of the glass medicine bottle, and a first photoelectric detector 202 is arranged on the other side of the glass medicine bottle;
step 2, the signal generating part 201 in the signal processing module 20 outputs a low-frequency sawtooth wave and a high-frequency sine wave, the low-frequency sawtooth wave and the high-frequency sine wave are sent to the laser control part 101 to drive the laser 102, the laser 102 emits laser light to irradiate and penetrate the glass medicine bottle, and the glass medicine bottle inclines for a certain angle theta along the direction of a laser light path1；
sending to the signal operation part 204 for signal operation; firstly, eliminating the refractive index factor r of the current signal i' (t);
step 6, subtracting the current signal i' (t) and i (t) after the refractive index factor r is eliminated, and obtaining the output current i of the signal operation part 204 after the interference signal is subtracted*(t)；
Step 7, changing the angle theta of the incident light1Thereby changing the refraction angle theta2Further, the optical length L is changed to d/cos theta2When the incident angle theta1Adjusting to a proper value, so that L/lambda is a positive integer M, and cos (4 pi L/lambda) is 1, thereby achieving the purpose of eliminating interference terms;
step 8, output current signal i of signal operation part 204*(t) sending the signal to a signal demodulation part, multiplying the signal by the high-frequency signal frequency-doubled signal output by the signal generation part, and extracting a second harmonic current signal
Step 9, second harmonic current signal
Sent to a harmonic analysis part 206 to be analyzed according to the peak value of the second harmonic current signal
The oxygen concentration N can be calculated back.
The invention has the technical effects that aiming at the etalon effect of the residual oxygen content detection of the glass medicine bottle, two photoelectric detectors are adopted to respectively detect the transmission light intensity at the two sides of the glass medicine bottle, the electric signals subjected to photoelectric conversion of the two photoelectric detectors are subjected to signal operation to eliminate the refractive index factor and realize the deduction of interference signals, and in addition, the proper incident angle is adjusted according to the phase difference relation among multiple beams so as to achieve the purpose of eliminating the interference item; and finally, the smoothness of the second harmonic signal is used as an optimization index, so that the etalon effect can be effectively inhibited, and the inversion accuracy of the oxygen concentration is improved.
The specific working process and working principle of the etalon effect suppression device for detecting the residual oxygen amount of the glass medicine bottle in the embodiment can specifically refer to the working process and working principle of the etalon effect suppression method for detecting the residual oxygen amount of the glass medicine bottle in the embodiment.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (9)
1. An etalon effect inhibition method for detecting residual oxygen amount of a glass medicine bottle is characterized by comprising the following steps:
acquiring main transmission light intensity after laser penetrates through the glass medicine bottle and transmission light intensity after the laser is reflected twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal;
acquiring the transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser is reflected for three times, and converting the transmission light intensity into a second current signal;
eliminating the refractive index factor of the second current signal to obtain a third current signal;
subtracting the third current signal from the first current signal to obtain an output current, wherein the calculation formula of the output current is as follows: i.e. i*(t)＝i0(t)αNL(1+r)2Wherein i is*(t) is the output current, i0(t) is the injection current of the laser, alpha is the absorption coefficient, and N is the oxygen concentrationDegree, L is the optical path of the laser penetrating the glass medicine bottle, and r is the reflectivity;
extracting a second harmonic current signal of the output current, the second harmonic current signal of the output current
Comprises the following steps:
where ω is the second harmonic current signal frequency, S2Is the second harmonic term coefficient;
and obtaining the oxygen concentration according to the second harmonic current signal.
2. The method for suppressing the etalon effect of claim 1, wherein the step of obtaining the main transmission intensity and the transmission intensity after the two reflections of the laser light after the laser light penetrates the glass vial, and before the step of converting the laser light into the first current signal further comprises:
adjusting the incident angle of the laser so that the incident angle satisfies L/lambda epsilon M, wherein M is a positive integer, L is the optical path of the laser penetrating through the glass medicine bottle, lambda is the laser wavelength, and L is d/cos theta2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
3. The etalon effect suppression method for residual oxygen content detection of glass medicine bottles according to claim 2, wherein a calculation formula for obtaining the oxygen concentration according to the second harmonic current signal is as follows:
wherein, N is the concentration of oxygen,
for the second harmonic current signal peak value, i0(t) is the injection current of the laser, L is laserThe optical path of light penetrating the glass medicine bottle, r is the reflectivity, S2Is the second harmonic term coefficient.
4. An etalon effect suppression device for detecting residual oxygen quantity of a glass medicine bottle is characterized in that,
the device comprises a light source module (10) and a signal processing module (20) connected with the light source module (10), wherein the light source module (10) is used for emitting laser irradiation and penetrating a glass medicine bottle;
the signal processing module (20) comprises a signal generating part (201), a first photo detector (202), a second photo detector (203), a signal operating part (204) connected with the first photo detector (202) and the second photo detector (203), a signal demodulating part (205) connected with the signal operating part (204), and a harmonic analyzing part (206) connected with the signal demodulating part (205), wherein:
the signal generating part (201) is used for driving the light source module (10) and outputting a high-frequency signal double-frequency signal to the signal demodulating part (205);
the first photoelectric detector (202) is used for acquiring the main transmission light intensity after the laser penetrates through the glass medicine bottle and the transmission light intensity after the laser is reflected twice, and converting the main transmission light intensity and the transmission light intensity into a first current signal;
the second photoelectric detector (203) is used for acquiring the transmission light intensity after the laser penetrates through the glass medicine bottle and after the laser is reflected once and the transmission light intensity after the laser is reflected three times, and converting the transmission light intensity into a second current signal;
the signal operation part (204) is used for obtaining output current according to the first current signal and the second current signal;
the signal demodulation section (205) for extracting a second harmonic current signal of the output current;
the harmonic analysis part (206) is used for obtaining the oxygen concentration according to the second harmonic current signal.
5. The etalon effect suppression device for residual oxygen content detection of glass medicine bottles of claim 4, wherein said device further comprises:
an incident angle adjusting module for adjusting the incident angle of the laser, so that the incident angle satisfies L/λ ∈ M, where M is a positive integer, where L is the optical path of the laser penetrating through the glass vial, λ is the laser wavelength, and L ═ d/cos θ2D is the diameter and length of the glass medicine bottle, theta2Is the angle of refraction.
6. The etalon effect suppression device for residual oxygen amount detection of glass medicine bottles according to claim 5, wherein said light source module (10) comprises a laser (102) and a laser control section (101) for controlling said laser (102), wherein,
the laser control part (101) comprises a current control part (1011) and a temperature control part (1012), wherein the current control part (1011) is used for controlling the working current of the laser (102), and the temperature control part (1012) is used for controlling the working temperature of the laser (102).
7. The etalon effect suppression device for residual oxygen volume detection of glass medicine bottles of claim 6, wherein said etalon effect suppression device comprises a first etalon body and a second etalon body,
the first photodetector (202) and the second photodetector (203) are respectively positioned on two sides of the glass medicine bottle, and the second photodetector (203) is positioned on the same side with the laser (102).
8. The etalon effect suppression device for residual oxygen amount detection of glass medicine bottles according to claim 7, wherein the signal output by the signal generation part (201) for driving the light source module (10) is a combined signal of a low frequency sawtooth wave and a high frequency sine wave.
9. The etalon effect suppression device for residual oxygen content detection of glass drug vials as defined in claim 8, wherein the laser (102) has a center wavelength of 760 nm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910270548.0A CN109959637B (en) | 2019-04-04 | 2019-04-04 | Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910270548.0A CN109959637B (en) | 2019-04-04 | 2019-04-04 | Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109959637A CN109959637A (en) | 2019-07-02 |
| CN109959637B true CN109959637B (en) | 2021-06-01 |
Family
ID=67025663
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910270548.0A Active CN109959637B (en) | 2019-04-04 | 2019-04-04 | Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109959637B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111024650B (en) * | 2019-12-10 | 2022-01-25 | 中南大学 | Method and device for detecting gas concentration in glass medicine bottle based on signal sparse reconstruction |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203101274U (en) * | 2013-03-04 | 2013-07-31 | 中国人民共和国黄岛出入境检验检疫局 | Device for detecting sulfur dioxide residue |
| CN103384811A (en) * | 2012-02-15 | 2013-11-06 | 株式会社新柯隆 | Optical film thickness measurement apparatus and thin-film forming apparatus using optical film thickness measurement apparatus |
| CN104568835A (en) * | 2015-01-21 | 2015-04-29 | 山东大学 | Method for eliminating second harmonic residual amplitude modulation in optical fiber sensing system |
| CN105548075A (en) * | 2016-01-08 | 2016-05-04 | 楚天科技股份有限公司 | Device and method for detecting oxygen content in glass medicine bottle |
| CN106872378A (en) * | 2017-01-13 | 2017-06-20 | 中南大学 | The temperature compensation of oxygen concentration in a kind of Wavelength modulation spectroscopy detection vial |
| CN106872404A (en) * | 2017-04-28 | 2017-06-20 | 中南大学 | The multiple-beam interference suppressing method of TDLAS gases detection in a kind of glass container |
| CN107641486A (en) * | 2012-11-16 | 2018-01-30 | 3M创新有限公司 | Adhesive, product and method comprising (methyl) acryloyl group side base |
| CN109100325A (en) * | 2018-06-14 | 2018-12-28 | 东南大学 | A kind of gas concentration measuring method based on spectral absorption second harmonic feature extraction |
| CN109187355A (en) * | 2018-09-04 | 2019-01-11 | 深圳市卡普瑞环境科技有限公司 | A kind of purging gas path device applied to optical cavity structure |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ITTO20060778A1 (en) * | 2006-10-30 | 2008-04-30 | Consiglio Nazionale Ricerche | EQUIPMENT FOR THE MEASUREMENT OF GAS PRESSURE IN CONTAINERS |
| GB0909662D0 (en) * | 2009-06-04 | 2009-07-22 | Cambridge Consultants | Device and method for determining the composition of a mixture of fluids |
| FI20115482A (en) * | 2011-05-18 | 2012-11-19 | Sparklike Ab Oy | Method and apparatus for determining the concentration of a gas component within a glass element |
-
2019
- 2019-04-04 CN CN201910270548.0A patent/CN109959637B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103384811A (en) * | 2012-02-15 | 2013-11-06 | 株式会社新柯隆 | Optical film thickness measurement apparatus and thin-film forming apparatus using optical film thickness measurement apparatus |
| CN107641486A (en) * | 2012-11-16 | 2018-01-30 | 3M创新有限公司 | Adhesive, product and method comprising (methyl) acryloyl group side base |
| CN203101274U (en) * | 2013-03-04 | 2013-07-31 | 中国人民共和国黄岛出入境检验检疫局 | Device for detecting sulfur dioxide residue |
| CN104568835A (en) * | 2015-01-21 | 2015-04-29 | 山东大学 | Method for eliminating second harmonic residual amplitude modulation in optical fiber sensing system |
| CN105548075A (en) * | 2016-01-08 | 2016-05-04 | 楚天科技股份有限公司 | Device and method for detecting oxygen content in glass medicine bottle |
| CN106872378A (en) * | 2017-01-13 | 2017-06-20 | 中南大学 | The temperature compensation of oxygen concentration in a kind of Wavelength modulation spectroscopy detection vial |
| CN106872404A (en) * | 2017-04-28 | 2017-06-20 | 中南大学 | The multiple-beam interference suppressing method of TDLAS gases detection in a kind of glass container |
| CN109100325A (en) * | 2018-06-14 | 2018-12-28 | 东南大学 | A kind of gas concentration measuring method based on spectral absorption second harmonic feature extraction |
| CN109187355A (en) * | 2018-09-04 | 2019-01-11 | 深圳市卡普瑞环境科技有限公司 | A kind of purging gas path device applied to optical cavity structure |
Non-Patent Citations (3)
| Title |
|---|
| Laser spectroscopic oxygen sensor using diffuse reflector based optical cell and advanced signal processing;J.Chen et al.;《Appl Phys B》;20100325;全文 * |
| 基于TDLAS检测西林瓶内氧气浓度的多光束干涉抑制方法;朱高峰 等;《光谱学与光谱分析》;20180228;全文 * |
| 封装西林药瓶残留氧气检测中的谐波基线校正和去噪方法;刘永胜 等;《光谱学与光谱分析》;20170831;全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109959637A (en) | 2019-07-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106802288B (en) | Gas-detecting device and method based on tunable laser and super continuous spectrums laser | |
| CN104280362B (en) | A kind of superheated vapor laser spectrum on-line detecting system | |
| CN106872404B (en) | The multiple-beam interference suppressing method of TDLAS gas detection in a kind of glass container | |
| CN113252204B (en) | Laser absorption spectrum temperature measurement method based on amplitude modulation | |
| CN104903704B (en) | Carry out the tunable diode laser absorption spectroscopy of steam measure | |
| CN105531580B (en) | Multicomponent laser type gas analyser | |
| CN110160976B (en) | Gas concentration detection method and system based on second harmonic interference envelope compensation | |
| KR100873550B1 (en) | Gas Detection Method and Gas Detection Device | |
| CN107345904B (en) | Method and device for detecting gas concentration based on optical absorption and interferometry | |
| WO2020238386A1 (en) | Detection method and detection device for trace gas | |
| KR100346353B1 (en) | Light absorption spectrum measuring method and apparatus thereof | |
| CN108061722A (en) | The detection device and detection method of a kind of carbonomonoxide concentration | |
| KR101767177B1 (en) | A measuring method for combustion gas | |
| CN114384045B (en) | Trace gas concentration and path length real-time detection system and method | |
| US8891085B2 (en) | Gas analyzer | |
| CN109959637B (en) | Etalon effect inhibition method and device for detecting residual oxygen of glass medicine bottle | |
| CN109270027A (en) | A kind of gas absorptivity On-line Measuring Method based on the fitting of Sine Modulated time domain | |
| CN114993987B (en) | Temperature and gas concentration measuring method and system based on absorption spectrum amplitude modulation | |
| CN109696418B (en) | Heterodyne balance detection system and detection method applied to TDLAS direct absorption method under low signal-to-noise ratio | |
| JP2008128942A (en) | Device for measuring photothermal conversion | |
| CN114279996B (en) | Gas-phase hydrogen peroxide concentration detection system based on off-axis integration cavity | |
| JP2004020539A (en) | Infrared circular dichroism measuring instrument and infrared circular dichroism measuring method | |
| CN110470623A (en) | Gas concentration detection system | |
| US12031903B2 (en) | Detection method and detection device for trace gas | |
| CN218766621U (en) | Multi-wavelength short-distance smoke parameter measuring system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20211021 Address after: 410600 No. 1, Xinkang Road, Yutan Town, Ningxiang City, Changsha City, Hunan Province Patentee after: TRUKING TECHNOLOGY Ltd. Address before: 410083 Hunan province Changsha Lushan Road No. 932 Patentee before: CENTRAL SOUTH University |
|
| TR01 | Transfer of patent right |