Summary of the invention
Based on this, it is necessary to it is more complicated for the terahertz time-domain spectroscopy instrument of test back wave and transmitted wave, using not
Just the problem of, provides a kind of terahertz time-domain spectroscopy instrument.
A kind of terahertz time-domain spectroscopy instrument, comprising:
Laser, for generating laser;
First spectroscope, for the laser to be divided into pump light and detection light;
Time delay equipment is set in the optical path of the detection light, and the time delay equipment is for adjusting the spy
Survey time delay of the light relative to the pump light;
Second spectroscope, for the detection light to be divided into the first detection light and the second detection light;
First Terahertz antenna, for emitting the first THz wave under the action of the pump light, and detect this first
The THz wave and the first detection light that THz wave is reflected by sample to be tested;
Second Terahertz antenna, for detect first THz wave transmit the THz wave after the sample to be tested and
The second detection light;
First processing module, spectral signal for being measured according to the first Terahertz antenna to the sample to be tested into
Row reflection signal analysis;And
Second processing module, spectral signal for being measured according to the second Terahertz antenna to the sample to be tested into
The analysis of row transmission signal.
Above-mentioned terahertz time-domain spectroscopy instrument is divided into the first detection light and the second detection since the second spectroscope will detect light
Light, and the first Terahertz antenna can receive to first and detect light, the second Terahertz antenna can receive to the second detection light.?
After first Terahertz antenna emits the first THz wave, the second Terahertz antenna can receive the first THz wave by test sample
The THz wave of product transmission, the first Terahertz antenna can also receive the THz wave reflected by sample to be tested.That is the first terahertz
Hereby antenna receives the THz wave and the first detection light of sample to be tested reflection, and it is saturating that the second Terahertz antenna receives sample to be tested
The THz wave penetrated and the second detection light.First processing module handles the spectral signal that the first Terahertz antenna measures, and obtains anti-
Penetrate spectrum.Second processing module handles the spectral signal that the second Terahertz antenna measures, and obtains transmitted spectrum.Therefore, it is above-mentioned too
Hertz spectrometer does not need change optical path or increases Terahertz antenna, so that it may easily measure to test sample after designing
The reflectance spectrum and transmitted spectrum of product, convenient for comprehensively analyzing the characteristic of sample to be tested, structure is simple, easy to use.
The pump light is also divided into the first pump light and the second pump by second spectroscope in one of the embodiments,
Pu light;The first Terahertz antenna is set in the optical path of first pump light;The second Terahertz antenna is set to
In the optical path of second pump light;The terahertz time-domain spectroscopy instrument further includes controller, controller control described the
One Terahertz antenna emits first THz wave under the action of first pump light, and controls second Terahertz
Antenna does not emit THz wave;Alternatively, the controller controls the second Terahertz antenna in the work of second pump light
With the second THz wave of lower transmitting, and controls the first Terahertz antenna and do not emit THz wave.
First pump light reaches the light of laser when the first Terahertz antenna in one of the embodiments,
Journey and second pump light reach the equivalent optical path of laser when the second Terahertz antenna;The first detection light arrives
When the light path of the laser and the second detection light reach the second Terahertz antenna when up to the first Terahertz antenna
The equivalent optical path of the laser.
The second Terahertz antenna receives the wave transmitted by the sample to be tested and institute in one of the embodiments,
The optical path difference for stating the received second detection light of the second Terahertz antenna changes in the first preset range;First terahertz
Hereby the distance between antenna and the second Terahertz antenna are in the second preset range;The first Terahertz antenna with it is described
The midpoint of the line of second Terahertz antenna is the position of the sample to be tested.
Terahertz time-domain spectroscopy instrument further includes position adjustment equipment in one of the embodiments, and the position adjusts and sets
Standby to connect with the time delay equipment, the position adjustment equipment is for driving the time delay equipment in the detection light
Direction on move back and forth so that the second Terahertz antenna receives the wave transmitted by the sample to be tested and described the
The optical path difference of the received second detection light of two Terahertz antennas changes within a preset range.
Terahertz time-domain spectroscopy instrument further includes first voltage module and second voltage module in one of the embodiments,
The controller is by controlling whether the first voltage module for the first Terahertz antenna provides bias voltage, with control
Whether the first Terahertz antenna emits first THz wave;The controller is by controlling the second voltage module
Whether for the second Terahertz antenna bias voltage is provided, to control whether the second Terahertz antenna emits described second
THz wave.
Terahertz time-domain spectroscopy instrument further includes the first directional coupler and the second directional couple in one of the embodiments,
Device, the first processing module and the first voltage module pass through first directional coupler and first Terahertz
Antenna connection, and the first processing module is connect with the controller;The Second processing module and the second voltage mould
Block passes through second directional coupler and connect with the second Terahertz antenna, and the Second processing module and the control
Device connection processed.
The time delay equipment includes time delay reflection microscope group in one of the embodiments, and the detection light is first
It re-shoots by time delay reflection microscope group to second spectroscope.
Terahertz time-domain spectroscopy instrument further includes the first condenser lens and the second condenser lens in one of the embodiments,
First condenser lens is set between the first Terahertz antenna and sample to be tested, and first condenser lens will be described
First THz wave focuses on the sample to be tested;Second condenser lens is set to the second Terahertz antenna and institute
It states between sample to be tested, the THz wave that the sample to be tested transmits is focused on second terahertz by second condenser lens
Hereby on antenna.
The laser is femtosecond pulse laser in one of the embodiments,.
Specific embodiment
In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing to the present invention
Specific embodiment be described in detail.
Fig. 1 is the light path schematic diagram of the terahertz time-domain spectroscopy instrument of an embodiment.A kind of terahertz time-domain spectroscopy instrument, including
Laser 1, the first spectroscope 3, time delay equipment 4, the second spectroscope 8, the first Terahertz antenna 11, the second Terahertz antenna
12, first processing module 13 and Second processing module 14.It can detecte the spy of sample to be tested 15 using terahertz time-domain spectroscopy instrument
Property.Sample to be tested 15, such as blade, tube wall, drug etc..
Laser 1 is for generating laser.Light source of the laser as terahertz time-domain spectroscopy instrument.In the present embodiment, laser 1
It is femtosecond pulse laser 1.Laser 1 generates femtosecond pulse.Light path described in present embodiment, refers both to by laser
The laser that source generates reaches the light path of a certain device.
First spectroscope 3 is set in the optical path of laser, and laser is divided into pump light and detection light.Pump light can be used for making
First Terahertz antenna 11 or the second Terahertz antenna 12 generate terahertz signal.Light is detected as test light.Since laser is
Pulse laser, pump light and detection light are also pulsed light wave.
Time delay equipment 4 is set in the optical path of detection light, and time delay equipment 4 is for adjusting detection light relative to pump
The time delay of Pu light.
Second spectroscope 8 is set in the optical path of detection light, and the second spectroscope 8 is divided into the first detection light for that will detect light
With the second detection light.
First Terahertz antenna 11 and the second Terahertz antenna 12, the first Terahertz antenna 11 are set to the first detection light
In optical path, the second Terahertz antenna 12 is set in the optical path of the second detection light.Work of the first Terahertz antenna 11 in pump light
With the first THz wave of lower transmitting.First Terahertz antenna 11 is also used to detect the first THz wave and reflects via sample to be tested 15
THz wave and first detection light.Since pump light is pulsed light wave, the first Terahertz antenna 11 can be at adjacent two
Time slot between pumping light pulse receives the THz wave reflected by sample to be tested 15.Sample to be tested 15 and can be designed
The distance of one Terahertz antenna 11 is appropriate value, so that being back to first by the THz wave that the first Terahertz antenna 11 reflects
The time of Terahertz antenna 11 is just in the time slot between two adjacent pumping light pulses.First detection light and to be measured
The THz wave that sample 15 reflects is coherent wave.First Terahertz antenna 11 measures what the first detection light and sample to be tested 15 reflected
THz wave can measure reflectance spectrum.
Second Terahertz antenna 12 is used to detect the THz wave that the first THz wave is transmitted via sample to be tested 15 and the
Two detection light.Second Terahertz antenna 12 also receives the second detection light.Similarly, the second detection light and sample to be tested 15 transmit too
Hertz wave is coherent wave.Second Terahertz antenna 12 measures the THz wave that the second detection light and sample to be tested 15 transmit can
Sample to be tested 15 is measured to the absorption spectrum of the first THz wave.
First processing module 13 and Second processing module 14, first processing module 13 are connect with the first Terahertz antenna 11.
First processing module 13 is used to carry out reflection signal to sample to be tested 15 according to the spectral signal that the first Terahertz antenna 11 measures
Analysis.From the foregoing, it will be observed that the spectral signal that the first Terahertz antenna 11 measures is that the first detection light and sample to be tested 15 reflect too
The coherent wave of Hertz wave.Sample to be tested 15 is obtained to the reflectance spectrum of the first THz wave, Jin Erke by the spectrum of the coherent wave
To analyze the correlation properties of sample to be tested 15.For example, internal to there is layering, first too for non-uniform sample to be tested 15
Hertz wave is reflected by sample to be tested 15, will form the reflected impulse of different delay.Thus the equal of sample to be tested 15 can be detected
Even property.
Second processing module 14 is connect with the second Terahertz antenna 12, and Second processing module 14 is used for according to the second Terahertz
The spectral signal that antenna 12 measures carries out transmission signal analysis to sample to be tested 15.The spectrum letter that second Terahertz antenna 12 measures
Number for second detection light and sample to be tested 15 transmit THz wave coherent wave.By the coherent wave spectrum, that is, transmitted spectrum just
Available sample to be tested 15 can analyze the characteristic of sample to be tested 15 to the absorption characteristic of the first THz wave.
Above-mentioned terahertz time-domain spectroscopy instrument is divided into the first detection light and the second detection since the second spectroscope 8 will detect light
Light, and the first Terahertz antenna 11 can receive to first and detect light, the second Terahertz antenna 12 can receive to the second detection
Light.After the first Terahertz antenna 11 emits the first THz wave to sample to be tested 15, the second Terahertz antenna 12 can be received
The THz wave transmitted to sample to be tested 15, the first Terahertz antenna 11 can also receive the Terahertz reflected by sample to be tested 15
Wave.That is the first Terahertz antenna 11 receives the THz wave and the first detection light of the reflection of sample to be tested 15, the second Terahertz day
Line 12 receives the THz wave and the second detection light of the transmission of sample to be tested 15.First processing module 13 handles the first Terahertz day
The spectral signal that line 11 measures, obtains reflectance spectrum.Second processing module 14 handles the spectrum that the second Terahertz antenna 12 measures
Signal obtains transmitted spectrum.Therefore, above-mentioned terahertz light spectrometer does not need change optical path or increases terahertz after designing
Hereby antenna, so that it may measure the reflectance spectrum and transmitted spectrum of sample to be tested 15, easily convenient for comprehensively analyzing sample to be tested
15 characteristic, structure is simple, easy to use.
As shown in Figure 1, reflecting mirror 2 can be set in the optical path of laser 1 and the first spectroscope 3, with both flexible settings
Between position.For example, laser is emitted by laser 1, it have passed through two reflecting mirrors 2 and reach the first spectroscope 3.Also, laser
The incidence angle for being incident to two reflecting mirrors 2 in succession is 45 °, i.e., the angle between the incidence angle and the angle of emergence of one reflecting mirror is
90 °, in this way, the more convenient relative position of flexible setting between the two.Similarly, the first spectroscope 3 and time delay equipment 4
In optical path, in the optical path of the first spectroscope 3 and the second spectroscope 8, in the optical path of time delay equipment 4 and the second spectroscope 8,
In the optical path of two spectroscopes 8 and the first Terahertz antenna 11 and in the optical path of the second spectroscope 8 and the second Terahertz antenna 12
Reflecting mirror 2 can be set.In the present embodiment, the incidence angle of the reflecting mirror 2 in optical path before the second spectroscope 8 is 45 °, with
So that the position comparison rule of each optical device.
Time delay equipment 4 includes that time delay reflects microscope group 5, and detection light first passes through time delay reflection microscope group 5 and reenters
It is incident upon the second spectroscope 8.It is corner cube mirror that time delay, which reflects microscope group 5,.Detect light incidence corner cube mirror when direction with
Transmission direction after corner cube mirror is opposite.Then, the detection light after corner cube mirror is anti-by the first reflecting mirror 6 again
It is incident upon the second spectroscope 8.Assuming that being L by the light path that corner cube mirror reflexes to the light wave of the first reflecting mirror 61。L1For x1To x2It
Between value.Wherein, x1And x2For positive number.
As shown in Figure 1, the second spectroscope 8 is set in the optical path of pump light in the present embodiment, the second spectroscope 8 will pump
Pu light is divided into the first pump light and the second pump light.That is the second spectroscope 8 is set in the optical path of detection light and pump light, is being incited somebody to action
In the case that detection light is divided into the first detection light and the second detection light, pump light is also divided into the first pump light and the second pumping
Light.In the present embodiment, light and pump light are detected respectively with two opposite faces of 45 ° of incident angles to the second spectroscope 8
On.First detection light perpendicular to detection light, second detection light in parallel with detection light.First pump light is parallel to pump light, and second
Pump light is perpendicular to pump light.
In the present embodiment, the first Terahertz antenna 11 and the second Terahertz antenna 12 are two identical Terahertz antennas.
First Terahertz antenna 11 can receive THz wave, can also emit THz wave.Second Terahertz antenna 12 can receive
THz wave can also emit THz wave.First Terahertz antenna 11 is set in the optical path of the first pump light.Second terahertz
Hereby antenna 12 is set in the optical path of the second pump light.I.e. the first Terahertz antenna 11 can be sent out under the action of the first pump light
Penetrate the first THz wave.Second Terahertz antenna 12 can emit the second THz wave under the action of the second pump light.As before
It states, in the present embodiment, sample to be tested 15 can be measured in the case where the first Terahertz antenna 11 emits the first THz wave
Reflectance spectrum and transmitted spectrum, without so that the second Terahertz antenna 12 also emits the second THz wave.In other embodiments
In, the second THz wave can also be emitted by the second Terahertz antenna 12, in this way, by the first Terahertz antenna 11 and the second terahertz
Hereby antenna 12 measures the reflectance spectrum of 15 both direction of sample to be tested simultaneously, more accurately measures the characteristic of test substance, specifically
The visual demand setting of situation.
In the present embodiment, sample to be tested 15 is set to the line of the first Terahertz antenna 11 and the second Terahertz antenna 12
Midpoint.Also, the optical path of 8 to the first Terahertz antenna 11 of the second spectroscope and 8 to the second Terahertz antenna 12 of the second spectroscope
Optical path axial symmetry.Assuming that the first Terahertz antenna 11 is L at a distance from the second Terahertz antenna 122.First Terahertz antenna
11 and second the distance between Terahertz antenna 12 in the second preset range so that the first Terahertz antenna 11 receive
First detection light and the THz wave coherence being reflected back by sample to be tested 15 are preferable.In the present embodiment, L2Range are as follows: L2∈
[2x1, 2x2]。
The light path of laser and the second pump light reach the second Terahertz when first pump light reaches the first Terahertz antenna 11
The equivalent optical path of laser when antenna 12.In the present embodiment, it is assumed that the first pump light reach the first Terahertz antenna 11 light path be
L0.The light path of laser and the second detection light reach the second Terahertz antenna 12 when first detection light reaches the first Terahertz antenna 11
The equivalent optical path of Shi Jiguang.Optical path i.e. as shown in Figure 1, can it is proper first detection light reach the first Terahertz antenna 11 when, swash
The total optical path L3 for the laser that light device 1 is emitted are as follows:
L3=L0+2L1 (1)
Similarly, when the second detection light reaches the second Terahertz antenna 12, the total optical path L for the laser that laser 1 is emitted4
Are as follows:
L4=L0+2L1 (2)
When the THz wave that the first Terahertz antenna 11 is reflected back by sample to be tested 15, the laser of the outgoing of laser 1
Total optical path L5Are as follows:
L5=L0+L2 (3)
Therefore, it can be obtained by formula (1) and (3), when the first Terahertz antenna 11 is reflected back THz wave by sample to be tested 15,
The optical path difference Δ L for two coherent waves that first Terahertz antenna 11 receives are as follows:
Δ L=2L1-L2 (4)
Similarly, it for the second Terahertz antenna 12, is transmitted when the second Terahertz antenna 12 is received by sample to be tested 15
When THz wave, the optical path difference for two coherent waves that 12 second Terahertz antenna 12 of the second Terahertz antenna receives is equal to Δ L.
Fig. 2 is the spectral schematic of the second Terahertz antenna 12 of an embodiment.In the present embodiment, the second Terahertz antenna
12 receive the wave S transmitted by sample to be tested 15a(t) light path of light F (t) is detected with the second Terahertz antenna 12 received second
Difference changes within a preset range.From the expression formula of Δ L, it is assumed that L1It is a variable, and variation range is in x1To x2Between,
L2Constant, then the second Terahertz antenna 12 receives the wave S transmitted by sample to be tested 15a(t) light path for detecting light F (t) with second
Difference changes in a range, this range is the first preset range.During the test, L can equably be adjusted1Size, i.e.,
So that L1In x1To x2Between even variation.As shown in Fig. 2, at the same time, the phase of the second detection light F (t) uniformly becomes at any time
Change.In the process, two coherent waves (the THz wave S transmitted by sample to be tested 15 that the second Terahertz antenna 12 receivesa
(t) and second detection light F (t)) superposition can obtain transmitted spectrum SF(t).Similarly, during the test, because equably adjusting
Save L1Size, first detection light phase also in even variation.In the process, the first Terahertz antenna 11 receive two
Coherent wave superposition can obtain reflectance spectrum.
Terahertz light spectrometer further includes position adjustment equipment (not shown), and position adjustment equipment and time delay equipment 4 connect
It connects, position adjustment equipment moves back and forth on the direction of detection light for driving time delay apparatus 4, so that the second Terahertz
Antenna 12 receives the wave transmitted by sample to be tested 15 and the optical path difference of the received second detection light of the second Terahertz antenna 12 exists
Variation in first preset range.Position adjustment equipment can be stepper motor or voice coil motor.
It should be noted that in other embodiments, being also not limited to and adjusting L1Size.To the second Terahertz antenna
12 receive the optical path difference of the wave transmitted by sample to be tested 15 and the received second detection light of the second Terahertz antenna 12 first
Change in preset range, also adjustable L2Size, concrete condition flexible choice regulative mode can be made.
Terahertz time-domain spectroscopy instrument further includes the first condenser lens 16 and the second condenser lens 17, and the first condenser lens 16 is set
It is placed between the first Terahertz antenna 11 and sample to be tested 15, the first condenser lens 16 focuses to the first THz wave to test sample
On product 15.According to light path principle, the first condenser lens 16 can also pass through the THz wave that sample to be tested 15 is reflected back
First condenser lens 16 focuses to the first Terahertz antenna 11.Second condenser lens 17 be set to the second Terahertz antenna 12 and to
Between sample 15, the THz wave that sample to be tested 15 transmits is focused on the second Terahertz antenna 12 by the second condenser lens 17
On.In this way, propagating and testing again light beam convergence, light energy is as strong as possible when may make test, so as to test sample
The reflectance spectrum of product 15 and the test effect of transmitted spectrum are preferable.
Fig. 3 is the schematic diagram of the terahertz time-domain spectroscopy instrument of an embodiment.In the present embodiment, terahertz time-domain spectroscopy instrument is also
Including controller 20, controller 20 controls the first Terahertz antenna 11 and emits the first Terahertz under the action of the first pump light
Wave, and control the second Terahertz antenna 12 and do not emit THz wave.Alternatively, controller 20 controls the second Terahertz antenna 12 the
Emit the second THz wave under the action of two pump lights, and controls the first Terahertz antenna 11 and do not emit THz wave.Terahertz
In time-domain spectroscopy instrument, the first Terahertz antenna 11 and the second Terahertz antenna 12 have a transmitting THz wave can measure to
The transmission tera-hertz spectra and reflected terahertz of sample 15 hereby spectrum.Due to the symmetry of whole system, the first Terahertz antenna
11 is identical with the working principle of the second Terahertz antenna 12.
Terahertz time-domain spectroscopy instrument further includes first voltage module 24 and second voltage module (not shown), and controller 20 is logical
Cross whether control first voltage module 24 is that the first Terahertz antenna 11 provides bias voltage, to control the first Terahertz antenna 11
Whether first THz wave is emitted.Specifically, while the first Terahertz antenna 11 receives the first pump light, controller 20 is controlled
First voltage module 24 processed is that the first Terahertz antenna 11 provides bias voltage, then the first Terahertz antenna 11 can emit first
THz wave.Namely first pump light and bias voltage be that the first Terahertz antenna 11 can generate the first THz wave two
Condition.Therefore, whether controller 20 generates first by the i.e. controllable first Terahertz antenna 11 of control first voltage module 24
THz wave.Whether controller 20 is that the second Terahertz antenna 12 provides bias voltage by control second voltage module, with control
Make whether the second Terahertz antenna 12 emits the second THz wave.Reason same as the first Terahertz antenna 11, controller 20
The second THz wave whether is generated by the i.e. controllable first Terahertz antenna 11 of control second voltage module.
Terahertz time-domain spectroscopy instrument further includes the first directional coupler 22 and the second directional coupler (not shown), at first
Reason module 13 is connect by the first directional coupler 22 with the first Terahertz antenna 11 with first voltage module 24, and at first
Reason module 13 is connect with controller 20.Second processing module 14 and second voltage module pass through the second directional coupler and second
Terahertz antenna 12 connects, and Second processing module 14 is connect with controller 20.Specifically, the effect of the first directional coupler 22
It is that can isolate first voltage module 24 with first processing module 13, supplies that first voltage module 24 to the first Terahertz antenna 11
Electricity, but first processing module 13 is not interfered with, the signal that the first Terahertz antenna 11 detects is may be coupled at first
Manage module 13.In this way, can make first voltage module 24 voltage signal and the first Terahertz antenna 11 measure it is relevant
It is unlikely to interfere with each other between signal, so that testing result is accurate.It is also same reason for the second directional coupler,
Also there is similar effect.Second Terahertz antenna 12, the second directional coupler, second voltage module, Second processing module 14 and
Connection relationship between controller is similar to the connection relationship of the device associated therewith of the first Terahertz antenna 11 in Fig. 3.
It should be noted that in terahertz time-domain spectroscopy instrument, laser 1 and the first Terahertz antenna 11 or the second Terahertz
Optical path between antenna 12 is not limited to present embodiment, can also be with flexible transformation optical path, as long as being able to achieve terahertz time-domain light
The function of spectrometer.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality
It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited
In contradiction, all should be considered as described in this specification.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously
It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art
It says, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to protection of the invention
Range.Therefore, the scope of protection of the patent of the invention shall be subject to the appended claims.