Collection device of transient absorption spectrum

Abstract

The utility model discloses a transient absorption spectrum acquisition device. The system comprises a laser, a first beam splitter, a wavelength range adjusting unit, an optical parameter amplifier, a first optical delay unit, an optical switch, a spectrum acquisition unit and a control unit. The optical parameter amplifier, the optical switch and the to-be-tested sample are sequentially arranged on a propagation light path of the pump light; the wavelength range adjusting unit, the to-be-detected sample and the spectrum acquisition unit are sequentially arranged on a propagation light path of the detection light; the wavelength range adjusting unit adjusts the detection light to comprise an infrared light wave band, a visible light wave band and an ultraviolet light wave band; and the control unit is used for receiving the detection spectrum data and determining transient absorption spectrum data of the to-be-detected sample according to the detection spectrum data. According to the technical scheme provided by the utility model, transient absorption spectrum data of ultraviolet light-visible light-infrared light wavebands can be simultaneously obtained, the detection range of the transient absorption spectrum is expanded, and the detection efficiency of the transient absorption spectrum of the ultraviolet light-visible light-infrared light wavebands is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of time-resolved spectroscopy, in particular to a collection device for transient absorption spectra. Background Art

[0002] Transient absorption spectroscopy is a "pump-probe" spectroscopy technique used to characterize the decay dynamics of photoinduced excited states on a time scale of sub-picosecond to nanoseconds, thereby characterizing photophysical and photochemical processes. Transient absorption spectroscopy requires the use of a near-infrared monochromatic femtosecond laser to generate supercontinuum white light as the probe light through a full-spectrum supercontinuum white light generator. The probe light generated by the traditional method is in the visible light band and can only characterize the transient absorption spectrum of the visible light band. It is not possible to characterize the transient absorption spectrum of the ultraviolet-visible-near infrared band at one time on this basis. Utility Model Content

[0003] The utility model provides a transient absorption spectrum acquisition device to solve the problem that the prior art cannot simultaneously acquire transient absorption spectra in infrared light bands and ultraviolet light bands, thereby affecting the transient absorption spectrum measurement efficiency.

[0004] According to one aspect of the utility model, a transient absorption spectrum acquisition device is provided, which includes:

[0005] A laser, a first beam splitter, a wavelength range adjustment unit, an optical parametric amplifier, a first optical delay unit, an optical switch, a spectrum collection unit and a control unit;

[0006] The laser is used to emit detection light to the first beam splitter;

[0007] The first beam splitter is used for splitting the detection light into pump light and detection light;

[0008] The optical parametric amplifier, the optical switch and the sample to be measured are sequentially arranged on the propagation optical path of the pump light; the optical parametric amplifier is used to adjust the wavelength range of the pump light; the control unit is respectively connected to the first optical delay unit and the optical switch for adjusting the time delay between the pump light and the detection light by controlling the first optical delay unit; and controls the conduction and shutdown of the optical switch to control the frequency of the pump light incident on the sample to be measured;

[0009] The wavelength range adjustment unit, the sample to be tested and the spectrum acquisition unit are sequentially arranged on the propagation optical path of the detection light; the wavelength range adjustment unit is used to adjust the detection light to include the infrared light band, the visible light band and the ultraviolet light band; the spectrum acquisition unit is used to receive the detection light absorbed by the sample to be tested and generate detection spectrum data; the control unit is also communicated with the spectrum acquisition unit, and is used to receive the detection spectrum data and determine the transient absorption spectrum data of the sample to be tested based on the detection spectrum data.

[0010] Optionally, the wavelength range adjustment unit includes a second beam splitter, a first wavelength band adjustment unit, a second wavelength band adjustment unit and a beam combining unit;

[0011] The second beam splitter is used to receive the detection light and split the detection light into a first sub-detection light and a second sub-detection light;

[0012] The first band adjustment unit is located on the propagation light path of the first sub-detection light, and is used to receive the first sub-detection light and adjust the first sub-detection light to a first band detection light; the first band detection light includes an ultraviolet light band and a visible light band;

[0013] The second band adjustment unit is located on the propagation light path of the second sub-detection light, and is used to receive the second sub-detection light and adjust the second sub-detection light to a second band detection light; the second band detection light includes an infrared light band and a visible light band;

[0014] The beam combining unit is respectively located on the propagation optical paths of the first-band detection light and the second-band detection light, and is used to receive the first-band detection light and the second-band detection light and output the combined beam of the first-band detection light and the second-band detection light to the sample to be tested.

[0015] Optionally, the first wavelength adjustment unit includes a frequency doubling crystal and a first nonlinear crystal which are sequentially arranged on a propagation optical path of the first sub-detection light;

[0016] The frequency doubling crystal is used to adjust the first sub-detection light into the third-band detection light; the first nonlinear crystal is used to change the wavelength of the third-band detection light to adjust the third-band detection light into the first-band detection light;

[0017] The second wavelength adjustment unit includes a second optical delay unit and a second nonlinear crystal which are sequentially arranged on the propagation path of the second sub-detection light;

[0018] The second optical delay unit is used to adjust the time delay of the second sub-detection light; the second nonlinear crystal is used to change the wavelength of the second sub-detection light to adjust the second sub-detection light to the second wavelength band detection light.

[0019] Optionally, the first band adjustment unit further includes a half wave plate;

[0020] The half wave plate is arranged in the propagation light path between the second beam splitter and the frequency doubling crystal.

[0021] Optionally, the first wavelength adjustment unit further includes a first attenuation plate, a second attenuation plate and a first filter group;

[0022] The first attenuation plate is arranged on the propagation optical path of the third-band detection light, and is used to adjust the light intensity of the third-band detection light; the second attenuation plate is arranged on the optical path of the first-band detection light, and is used to adjust the light intensity of the first-band detection light;

[0023] The first filter group is arranged in the optical path between the second attenuation plate and the beam combining unit;

[0024] The second waveband adjustment unit further includes a third attenuation plate, a fourth attenuation plate and a second filter group;

[0025] The third attenuation plate is arranged on the propagation optical path of the second sub-detection light, and is used to adjust the light intensity of the second sub-detection light; the fourth attenuation plate is arranged on the propagation optical path of the second-band detection light, and is used to adjust the light intensity of the second-band detection light;

[0026] The second filter group is arranged in the optical path between the fourth attenuation plate and the beam combining unit.

[0027] Optionally, the first wavelength adjustment unit further includes a first focusing lens and a first collimating lens;

[0028] The first focusing lens is arranged on the propagation optical path of the detection light of the third wavelength band; the first collimating lens is arranged on the propagation optical path of the detection light of the first wavelength band;

[0029] The second wavelength adjustment unit includes a second focusing lens and a second collimating lens;

[0030] The second focusing lens is arranged on the propagation optical path of the second sub-detection light; the second collimating lens is arranged on the propagation optical path of the second-band detection light.

[0031] Optionally, the first band adjustment unit further includes a dichroic mirror;

[0032] The dichroic mirror is arranged in the propagation light path between the frequency doubling crystal and the first nonlinear crystal.

[0033] Optionally, the wavelength range adjustment unit further includes an enhancement unit;

[0034] The enhancement unit is arranged in the propagation light path between the first band adjustment unit and the beam combining unit, and is used to enhance the light intensity of the set wavelength range in the first band detection light.

[0035] Optionally, the spectrum acquisition unit includes a wavelength selection unit, a first sub-spectrum acquisition unit and a second sub-spectrum acquisition unit;

[0036] The wavelength selection unit is used to split the detection light absorbed by the sample to be tested into a first-band detection light and a second-band detection light; the first-band detection light includes an ultraviolet light band and a visible light band, and the second-band detection light includes an infrared light band and a visible light band;

[0037] The first sub-spectrum acquisition unit is used to receive the first-band detection light and generate the first-band spectrum data, and the second sub-spectrum acquisition unit is used to receive the second-band detection light and generate the second-band spectrum data; the detection spectrum data includes the first-band spectrum data and the second-band spectrum data.

[0038] Optionally, the first optical delay unit is arranged in a propagation optical path between the optical parametric amplifier and the optical switch;

[0039] And / or, the first optical delay unit is arranged in the propagation light path between the wavelength range adjustment unit and the sample to be measured.

[0040] The technical solution of the utility model is to set a wavelength range adjustment unit in the acquisition device, and use the wavelength range adjustment unit to broaden the detection light into a wide wavelength light beam in the ultraviolet light-visible light-infrared light band, so that the transient absorption spectrum data of the ultraviolet light-visible light-infrared light band can be obtained simultaneously when performing transient absorption spectrum calculation, which simplifies the acquisition device and expands the detection range of the transient absorption spectrum, thereby improving the detection efficiency of the transient absorption spectrum in the ultraviolet light-visible light-infrared light band.

[0041] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 It is a structural schematic diagram of a transient absorption spectrum collection device provided according to an embodiment of the utility model;

[0044] Figure 2 It is a structural schematic diagram of a wavelength range adjustment unit provided according to an embodiment of the utility model. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0047] Figure 1 Schematic diagram of a transient absorption spectrum acquisition device provided according to an embodiment of the utility model. Figure 1 As shown, the collection device includes:

[0048] Laser 1, first beam splitter 2, wavelength range adjustment unit 3, optical parametric amplifier 4, first optical delay unit 5, optical switch 6, spectrum collection unit 7 and control unit 8;

[0049] The laser 1 is used to emit a detection light a to the first beam splitter 2;

[0050] The first beam splitter 2 is used to split the detection light a into pump light b and detection light c;

[0051] The optical parametric amplifier 4, the optical switch 6 and the sample to be measured 9 are sequentially arranged on the propagation optical path of the pump light b; the optical parametric amplifier 4 is used to adjust the wavelength range of the pump light b; the control unit 8 is respectively connected to the first optical delay unit 5 and the optical switch 6 for communicating with each other, and is used to adjust the time delay between the pump light b and the detection light c by controlling the first optical delay unit 5; and controls the conduction and shutdown of the optical switch 6 to control the frequency of the pump light b incident on the sample to be measured 9;

[0052] The wavelength range adjustment unit 3, the sample to be tested 9 and the spectrum acquisition unit 7 are sequentially arranged on the propagation optical path of the detection light c; the wavelength range adjustment unit 3 is used to adjust the detection light c to include the infrared light band, the visible light band and the ultraviolet light band; the spectrum acquisition unit 7 is used to receive the detection light c absorbed by the sample to be tested 9 and generate detection spectrum data; the control unit 8 is also communicated with the spectrum acquisition unit 7, and is used to receive the detection spectrum data and determine the transient absorption spectrum data of the sample to be tested 9 according to the detection spectrum data.

[0053] Among them, the laser 1 can be a femtosecond laser 1, which is used to emit a laser beam, and the laser beam is the detection light a. In some embodiments, the detection light a can be a single-wavelength laser beam of 800nm ​​or 1030nm. The first beam splitter 2 is used to split the detection light a into pump light b and detection light c. The optical parametric amplifier 4 is used to change the wavelength of the pump light b to adjust the single-wavelength pump light b to a continuously adjustable wide-wavelength pump light b and allow the continuously adjustable single-wavelength pump light b to be incident on the optical switch 6. The control unit 8 is connected to the optical switch 6 for communication, and controls the on and off of the optical switch 6 to control whether the pump light b is incident on the sample to be tested 9 and the frequency of the incident light to the sample to be tested 9. The first optical delay unit 5 is used to adjust the time delay between the pump light b and the detection light c by changing the optical path of the pump light b or the detection light c. The control unit 8 is in communication connection with the first optical delay unit 5. The control unit 8 can adjust the delay between the pump light b and the detection light c through the first optical delay unit 5 to measure the absorption of the detection light c by the sample 9 under different delay times. In some embodiments, the first optical delay unit 5 is arranged in the propagation optical path between the optical parametric amplifier 4 and the optical switch 6; and / or, the first optical delay unit 5 is arranged in the propagation optical path between the wavelength range adjustment unit 3 and the sample 9 under test. The first optical delay unit 5 can be arranged on the optical path of the detection light c or the optical path of the pump light b, so as to ensure the time delay between the detection light c and the pump light b.

[0054] Among them, the wavelength range adjustment unit 3 can be used to adjust the wavelength of the detection light c, and widen the single-wavelength detection light c into a wide-wavelength detection light c, and the wavelength band of the detection light c includes the infrared light band, the visible light band and the ultraviolet light band. It can be understood that the wavelength range adjustment unit 3 has two functions of adjusting the wavelength and widening the wavelength. Since the detection light a is generally a single-wavelength laser beam of 800nm ​​or 1030nm, the existing technology can only adjust the detection light c to a beam including the infrared light band and the visible light band, generally a wide-wavelength detection light c of 450nm to 900nm in the process of adjusting the wavelength. When the transient absorption spectrum of the ultraviolet light band needs to be obtained, the optical path adjustment needs to be reset, and the measurement of the transient absorption spectra of the infrared band and the ultraviolet band cannot be taken into account at the same time. The wavelength range adjustment unit 3 can widen the single-wavelength laser beam into a wide-wavelength beam that takes into account the infrared light band, the visible light band and the ultraviolet light band, and realize the measurement of the transient absorption spectra of the infrared band and the ultraviolet band.

[0055] The spectrum acquisition unit 7 is used to receive the detection light c absorbed by the sample 9 to be tested and generate detection spectrum data, and transmit the detection spectrum data to the control unit 8, and the control unit 8 determines the transient absorption spectrum data of the sample 9 to be tested according to the detection spectrum data. It can be understood that the transient absorption spectrum data includes transient absorption spectrum data of the infrared light band and transient absorption spectrum data of the ultraviolet light band.

[0056] In some embodiments, the acquisition device further includes a timing synchronization module 10 , which is in communication with the control unit 8 and is used to control the optical switch 6 and the spectrum acquisition unit 7 to have consistent working timings.

[0057] Specifically, the working process of the acquisition device is as follows: the first beam splitter 2 splits the detection light a emitted by the laser 1 into pump light b and detection light c. The pump light b enters the optical parametric amplifier 4, the optical parametric amplifier 4 adjusts the pump light b to a wide-wavelength pump light b and enters the first optical delay unit 5, the first optical delay unit 5 changes the optical path of the pump light b, and inputs the pump light b into the optical switch 6, the control unit 8 controls the frequency of the pump light b irradiating the sample 9 to be tested by controlling the frequency of the optical switch 6; the detection light c enters the wavelength range adjustment unit 3, the wavelength range adjustment unit 3 broadens the detection light c into a wide-wavelength beam of ultraviolet light-visible light-infrared light and enters the sample 9 to be tested. The spectrum acquisition unit 7 receives the detection light c. Due to the working state of the optical switch 6, the detection spectrum data of the detection light c received by the spectrum acquisition unit 7 is divided into two states: with the pump light b irradiating (pump-on) and without the pump light b irradiating (pump-off). The control unit 8 receives the detection spectrum data of the spectrum acquisition unit 7 and calculates the transient absorption spectrum ΔA under the time delay. The spectrum I of the detection light c under the irradiation of the pump light b is calculated. pump-onSpectrum I of the probe light c without pump light b pump-off According to the following formula:

[0058]

[0059] The technical solution of the embodiment of the utility model is to set a wavelength range adjustment unit in the acquisition device, and use the wavelength range adjustment unit to broaden the detection light into a wide wavelength light beam in the ultraviolet light-visible light-infrared light band, so that the transient absorption spectrum data in the ultraviolet light-visible light-infrared light band can be obtained simultaneously when performing transient absorption spectrum calculation, which simplifies the acquisition device and expands the detection range of the transient absorption spectrum, thereby improving the detection efficiency of the transient absorption spectrum in the ultraviolet light-visible light-infrared light band.

[0060] Optional, continue to refer to Figure 1 As shown, the spectrum acquisition unit 7 includes a wavelength selection unit 73, a first sub-spectrum acquisition unit 71 and a second sub-spectrum acquisition unit 72;

[0061] The wavelength selection unit 73 is used to split the detection light c absorbed by the sample 9 into a first-band detection light c1 and a second-band detection light c2; the first-band detection light c1 includes an ultraviolet light band and a visible light band, and the second-band detection light c2 includes an infrared light band and a visible light band;

[0062] The first sub-spectrum acquisition unit 71 is used to receive the first-band detection light c1 and generate first-band spectrum data, and the second sub-spectrum acquisition unit 72 is used to receive the second-band detection light c2 and generate second-band spectrum data; the detection spectrum data includes first-band spectrum data and second-band spectrum data.

[0063] Among them, due to the limitation of detection accuracy of the spectrum acquisition unit 7 or the band requirement of the detection light c of the transient absorption spectrum, the spectrum acquisition unit 7 can be divided into a first sub-spectrum acquisition unit 71 and a second sub-spectrum acquisition unit 72 to respectively detect the transient absorption spectra of the detection light c of different bands.

[0064] Among them, the wavelength selection unit 73 can be a near-infrared long-pass filter, which can transmit the first-band detection light c1 and reflect the second-band detection light c2, thereby splitting the detection light c and respectively incident on the first sub-spectrum acquisition unit 71 and the second sub-spectrum acquisition unit 72, thereby realizing separate measurements of transient absorption spectra in different bands.

[0065] Optional, Figure 2 is a schematic diagram of a wavelength range adjustment unit according to an embodiment of the present invention, combined with Figure 1 and Figure 2As shown, the wavelength range adjustment unit 3 includes a second beam splitter 31, a first wavelength band adjustment unit 32, a second wavelength band adjustment unit 33 and a beam combining unit 34;

[0066] The second beam splitter 31 is used to receive the detection light c and split the detection light c into a first detection sub-light a1 and a second detection sub-light a2;

[0067] The first wavelength adjustment unit 32 is located on the propagation light path of the first detection light sub-light a1, and is used to receive the first detection light sub-light a1 and adjust the first detection light sub-light a1 to a first wavelength detection light c1; the wavelength of the first wavelength detection light c1 includes an ultraviolet wavelength band and a visible wavelength band;

[0068] The second wavelength adjustment unit 33 is located on the propagation optical path of the second detection sub-light a2, and is used to receive the second detection sub-light a2 and adjust the second detection sub-light a2 to a second wavelength detection light c2; the wavelength of the second wavelength detection light c2 includes an infrared wavelength band and a visible wavelength band;

[0069] The beam combining unit 34 is respectively located on the propagation optical paths of the first-band detection light c1 and the second-band detection light c2, and is used to receive the first-band detection light c1 and the second-band detection light c2 and combine the first-band detection light c1 and the second-band detection light c2 to output to the sample 9 to be tested.

[0070] The second beam splitter 31 can be used to split the detection light c into a first sub-detection light a1 and a second sub-detection light a2 and respectively enter the first band adjustment unit 32 and the second band adjustment unit 33. The first band adjustment unit 32 can be used to adjust the first sub-detection light a1 into a first band detection light c1, wherein the first sub-detection light a1 is a single wavelength light beam, and the band of the first band detection light c1 includes an ultraviolet light band and a visible light band.

[0071] The second wavelength adjustment unit 33 can be used to adjust the second sub-detection light a2 to the second wavelength detection light c2, and the wavelength of the second wavelength detection light c2 includes the ultraviolet wavelength band and the infrared wavelength band. The beam combining unit 34 further combines the first wavelength detection light c1 and the second wavelength detection light c2, so that the combined detection light c includes the ultraviolet wavelength band and the near infrared wavelength band.

[0072] It can be understood that since the greater the intensity of light, the easier it is to measure weak signals, and the detection light c is output by combining the beams, and the first-band detection light c1 includes the ultraviolet light band and the visible light band, and the second-band detection light c2 includes the infrared light band and the visible light band, the light of the same wavelength part of the first-band detection light c1 and the second-band detection light c2 overlap after the first-band detection light c1 and the second-band detection light c2 are combined, making the spectrum of the total detection light c smoother, thereby improving the intensity of the overlapping part of the detection light c and improving the signal-to-noise ratio of the transient absorption spectrum.

[0073] Optional, continue to refer to Figure 1 and Figure 2 As shown, the first wavelength adjustment unit 32 includes a frequency doubling crystal 321 and a first nonlinear crystal 322 which are sequentially arranged on the propagation optical path of the first detection sub-light a1;

[0074] The frequency doubling crystal 321 is used to adjust the first sub-detection light a1 to the third-band detection light c; the first nonlinear crystal 322 is used to change the wavelength of the third-band detection light c to adjust the third-band detection light c to the first-band detection light c1;

[0075] The second wavelength adjustment unit 33 includes a second optical delay unit 331 and a second nonlinear crystal 332 which are sequentially arranged on the propagation path of the second detection sub-light a2;

[0076] The second optical delay unit 331 is used to adjust the time delay of the second detection sub-light a2; the second nonlinear crystal 332 is used to change the wavelength of the second detection sub-light a2 to adjust the second detection sub-light a2 to the second wavelength band detection light c2.

[0077] Among them, the frequency doubling crystal 321 can be used to change the frequency of the first sub-detection light a1, and then change the wavelength of the first sub-detection light a1. After modulation by the nonlinear effect, the wavelength of the third-band detection light c is half of the wavelength of the first sub-detection light a1. The principle of the frequency doubling crystal 321 can be based on the second-order nonlinear optical effect. The frequency of the first sub-detection light a1 is multiplied by the frequency doubling crystal 321 to become the third-band detection light c3. The wavelength of the third-band detection light c3 includes half of the wavelength of the first sub-detection light a1. In some embodiments, the frequency doubling crystal 321 can be made of lithium borate crystal material.

[0078] The first nonlinear crystal 322 can be used to change the frequency of the third-band detection light c3 and thus change the wavelength of the third-band detection light c3, and convert the third-band detection light c3 into the first-band detection light c1. In some embodiments, the first nonlinear crystal 322 can be a yttrium aluminum garnet crystal. Similarly, the second nonlinear crystal 332 can be used to change the frequency of the second sub-detection light a2, and thus change the wavelength of the second sub-detection light a2 to output the second-band detection light c2.

[0079] The second optical delay unit 331 can be a manual delay line for adjusting the time delay of the second detection sub-light a2. The optical path difference of the second detection sub-light a2 is adjusted by the manual optical delay line to ensure that the first band detection light c1 and the second band detection light c2 have smaller pulse widths.

[0080] The technical solution of the embodiment of the utility model ensures that the first-band detection light includes the ultraviolet light band and the visible light band by setting a frequency doubling crystal and a first nonlinear crystal in the first-band adjustment unit; and ensures that the second-band detection light includes the infrared light band and the visible light band by setting a second nonlinear crystal in the second-band adjustment unit, thereby ensuring the broadened output of the detection light.

[0081] Optional, continue to refer to Figure 1 and Figure 2 As shown, the first band adjustment unit 32 further includes a half wave plate 323;

[0082] The half wave plate 323 is disposed in the propagation light path between the second beam splitter 31 and the frequency doubling crystal 321 .

[0083] The half wave plate 323 can be used to adjust the polarization direction of the first detection sub-light a1 to match the frequency doubling crystal 321 , thereby improving the conversion efficiency of the first detection sub-light a1 .

[0084] In some embodiments, the first wavelength adjustment unit 32 further includes a dichroic mirror 324; the dichroic mirror 324 is disposed in the propagation light path between the frequency doubling crystal 321 and the first nonlinear crystal 322. The dichroic mirror 324 plays a filtering role, reflects the third wavelength detection light c3 of a specific wavelength band, and transmits the third wavelength detection light c3 of a non-specific wavelength band. In order to ensure the accuracy and collimation of filtering the third wavelength detection light c3, two groups of dichroic mirrors 324 with different reflection directions can be disposed in the propagation light path between the frequency doubling crystal 321 and the first nonlinear crystal 322 to ensure the accuracy of transmission of the third wavelength detection light c3.

[0085] Optionally, the first wavelength adjustment unit 32 further includes a first attenuation plate 325, a second attenuation plate 326 and a first filter group 327;

[0086] The first attenuation plate 325 is disposed on the propagation optical path of the third-band detection light c3, and is used to adjust the light intensity of the third-band detection light c3; the second attenuation plate 326 is disposed on the optical path of the first-band detection light c1, and is used to adjust the light intensity of the first-band detection light c1;

[0087] The first filter group 327 is arranged in the optical path between the second attenuation plate 326 and the beam combining unit 34;

[0088] The second wavelength adjustment unit 33 further includes a third attenuation plate 333, a fourth attenuation plate 334 and a second filter group 335;

[0089] The third attenuation plate 333 is arranged on the propagation optical path of the second sub-detection light a2, and is used to adjust the light intensity of the second sub-detection light a2; the fourth attenuation plate 334 is arranged on the propagation optical path of the second-band detection light c2, and is used to adjust the light intensity of the second-band detection light c2;

[0090] The second filter group 335 is disposed in the optical path between the fourth attenuation plate 334 and the beam combining unit 34 .

[0091] Among them, the first attenuation plate 325 is used to adjust the intensity of the third-band detection light c3 to avoid the third-band detection light c3 from being too intense to damage the first nonlinear crystal 322, thereby ensuring that the first nonlinear crystal 322 outputs a stable supercontinuous first-band detection light c1; the third attenuation plate 333 is used to adjust the intensity of the second sub-detection light a2 to avoid the second sub-detection light a2 from being too intense to damage the second nonlinear crystal 332, thereby ensuring that the second nonlinear crystal 332 outputs a stable supercontinuous second-band detection light c2.

[0092] Among them, the second attenuation plate 326 is used to adjust the intensity of the first band detection light c1, and the fourth attenuation plate 334 is used to adjust the intensity of the second band detection light c2. The attenuation degree of the second attenuation plate 326 and the attenuation degree of the fourth attenuation plate 334 can be determined according to the detection requirements of the sample 9 to be tested, and the embodiment of the utility model does not limit this.

[0093] The first filter group 327 is used to filter the set band of the first band detection light c1 to obtain the smooth first band detection light c1, and the second filter group 335 is used to filter the set band of the second band detection light c2 to obtain the smooth second band detection light c2. It can be understood that the set band of the first filter group 327 and the set band of the second filter group 335 can be determined according to the detection requirements of the sample 9 to be tested, and the embodiment of the utility model does not limit this.

[0094] The technical solution of the embodiment of the utility model optimizes the optical path of the first band detection light and the optical path of the second band detection light by setting the first attenuation plate, the second attenuation plate and the first filter group in the first band adjustment unit, and setting the third attenuation plate, the fourth attenuation plate and the second filter group in the second band adjustment unit.

[0095] Optional, continue to refer to Figure 1 and Figure 2 As shown, the first wavelength adjustment unit 32 further includes a first focusing lens 328 and a first collimating lens 329;

[0096] The first focusing lens 328 is arranged on the propagation optical path of the third-band detection light c3; the first collimating lens 329 is arranged on the propagation optical path of the first-band detection light c1;

[0097] The second wavelength adjustment unit 33 includes a second focusing lens 336 and a second collimating lens 337;

[0098] The second focusing lens 336 is arranged on the propagation optical path of the second sub-detection light a2; the second collimating lens 337 is arranged on the propagation optical path of the second-band detection light c2.

[0099] Among them, the first focusing lens 328 is used to converge the third-band detection light c3 into the first nonlinear crystal 322, and the first collimating lens 329 is used to convert the first-band detection light c1 into parallel light for collimated output; the second focusing lens 336 is used to converge the second sub-detection light a2 into the second nonlinear crystal 332, and the second collimating lens 337 is used to convert the second-band detection light c2 into parallel light for collimated output.

[0100] The technical solution of the embodiment of the utility model ensures the convergence output of the third-band detection light and the second detection light in the first nonlinear crystal and the second nonlinear crystal by setting a first focusing lens, a first collimating lens, a second focusing lens and a second collimating lens, thereby improving the efficiency and stability of the detection light conversion.

[0101] Optional, continue to refer to Figure 1 and Figure 2 As shown, the wavelength range adjustment unit 3 further includes an enhancement unit 320;

[0102] The enhancement unit 320 is disposed in the propagation light path between the first wavelength band adjustment unit 32 and the beam combining unit 34 , and is used to enhance the light intensity of the first wavelength band detection light c1 within a set wavelength range.

[0103] Among them, the enhancement unit 320 can be used to enhance the light intensity of the ultraviolet light band and reduce the relative light intensity of the visible light band, so that the combined detection light c has a smoother spectrum, thereby improving the stability of the detection light c output.

[0104] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A transient absorption spectrum acquisition device, characterized in that: include: A laser, a first beam splitter, a wavelength range adjustment unit, an optical parametric amplifier, a first optical delay unit, an optical switch, a spectrum collection unit and a control unit; The laser is used to emit detection light to the first beam splitter; The first beam splitter is used to split the detection light into pump light and detection light; The optical parametric amplifier, the optical switch and the sample to be measured are sequentially arranged on the propagation optical path of the pump light; the optical parametric amplifier is used to adjust the wavelength range of the pump light; the control unit is respectively connected to the first optical delay unit and the optical switch for adjusting the time delay between the pump light and the detection light by controlling the first optical delay unit; and controls the on and off of the optical switch to control the frequency of the pump light incident on the sample to be measured; The wavelength range adjustment unit, the sample to be tested and the spectrum acquisition unit are sequentially arranged on the propagation optical path of the detection light; the wavelength range adjustment unit is used to adjust the detection light to include infrared light band, visible light band and ultraviolet light band; the spectrum acquisition unit is used to receive the detection light after being absorbed by the sample to be tested and generate detection spectrum data; the control unit is also communicated with the spectrum acquisition unit, and is used to receive the detection spectrum data and determine the transient absorption spectrum data of the sample to be tested based on the detection spectrum data.

2. The collection device according to claim 1, characterized in that: The wavelength range adjustment unit includes a second beam splitter, a first wavelength band adjustment unit, a second wavelength band adjustment unit and a beam combining unit; The second beam splitter is used to receive the detection light and split the detection light into a first sub-detection light and a second sub-detection light; The first wavelength adjustment unit is located on the propagation optical path of the first sub-detection light, and is used to receive the first sub-detection light and adjust the first sub-detection light to a first wavelength detection light; the wavelength of the first wavelength detection light includes an ultraviolet light band and a visible light band; The second wavelength band adjustment unit is located on the propagation optical path of the second sub-detection light, and is used to receive the second sub-detection light and adjust the second sub-detection light to a second wavelength band detection light; the wavelength band of the second wavelength band detection light includes an infrared light band and a visible light band; The beam combining unit is respectively located on the propagation optical paths of the first-band detection light and the second-band detection light, and is used to receive the first-band detection light and the second-band detection light and output the first-band detection light and the second-band detection light to the sample to be tested.

3. The collection device according to claim 2, characterized in that: The first band adjustment unit comprises a frequency doubling crystal and a first nonlinear crystal which are sequentially arranged on the propagation optical path of the first sub-detection light; The frequency doubling crystal is used to adjust the first sub-detection light into a third-band detection light; the first nonlinear crystal is used to change the wavelength of the third-band detection light to adjust the third-band detection light into the first-band detection light; The second wavelength band adjustment unit comprises a second optical delay unit and a second nonlinear crystal which are sequentially arranged on the propagation path of the second sub-detection light; The second optical delay unit is used to adjust the time delay of the second sub-detection light; the second nonlinear crystal is used to change the wavelength of the second sub-detection light to adjust the second sub-detection light to the second wavelength band detection light.

4. The collection device according to claim 3, characterized in that: The first waveband adjustment unit further includes a half wave plate; The half wave plate is arranged in the propagation light path between the second beam splitter and the frequency doubling crystal.

5. The collection device according to claim 3, characterized in that: The first band adjustment unit further includes a first attenuation plate, a second attenuation plate and a first filter group; The first attenuation plate is arranged on the propagation optical path of the third-band detection light, and is used to adjust the light intensity of the third-band detection light; the second attenuation plate is arranged on the optical path of the first-band detection light, and is used to adjust the light intensity of the first-band detection light; The first filter group is arranged in the optical path between the second attenuation plate and the beam combining unit; The second waveband adjustment unit further includes a third attenuation plate, a fourth attenuation plate and a second filter group; The third attenuation plate is arranged on the propagation optical path of the second sub-detection light, and is used to adjust the light intensity of the second sub-detection light; the fourth attenuation plate is arranged on the propagation optical path of the second-band detection light, and is used to adjust the light intensity of the second-band detection light; The second filter group is arranged in the optical path between the fourth attenuation plate and the beam combining unit.

6. The collection device according to claim 3, characterized in that: The first wavelength adjustment unit further includes a first focusing lens and a first collimating lens; The first focusing lens is arranged on the propagation optical path of the detection light of the third wavelength band; the first collimating lens is arranged on the propagation optical path of the detection light of the first wavelength band; The second wavelength adjustment unit includes a second focusing lens and a second collimating lens; The second focusing lens is arranged on the propagation optical path of the second sub-detection light; the second collimating lens is arranged on the propagation optical path of the second-band detection light.

7. The collection device according to claim 3, characterized in that: The first band adjustment unit further includes a dichroic mirror; The dichroic mirror is arranged in a propagation light path between the frequency doubling crystal and the first nonlinear crystal.

8. The collection device according to claim 2, characterized in that: The wavelength range adjustment unit also includes an enhancement unit; The enhancement unit is disposed in the propagation light path between the first wavelength band adjustment unit and the beam combining unit, and is used to enhance the light intensity of a set wavelength range in the first wavelength band detection light.

9. The collection device according to claim 1, characterized in that: The spectrum acquisition unit includes a wavelength selection unit, a first sub-spectrum acquisition unit and a second sub-spectrum acquisition unit; The wavelength selection unit is used to split the detection light after being absorbed by the sample to be tested into a first-band detection light and a second-band detection light; the first-band detection light includes an ultraviolet light band and a visible light band, and the second-band detection light includes an infrared light band and a visible light band; The first sub-spectrum acquisition unit is used to receive the first-band detection light and generate the first-band spectrum data, and the second sub-spectrum acquisition unit is used to receive the second-band detection light and generate the second-band spectrum data; the detection spectrum data includes the first-band spectrum data and the second-band spectrum data.

10. The collection device according to claim 1, characterized in that: The first optical delay unit is arranged in a propagation optical path between the optical parametric amplifier and the optical switch; And / or, the first optical delay unit is arranged in the propagation light path between the wavelength range adjustment unit and the sample to be measured.

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