WO2022036582A1

WO2022036582A1 - Time-resolved spectrometer realizing synchronization on basis of electronics

Info

Publication number: WO2022036582A1
Application number: PCT/CN2020/109972
Authority: WO
Inventors: 蔡贞贞; 甘继伟; 仲路铭
Original assignee: 江苏博创翰林光电高科技有限公司
Priority date: 2020-08-17
Filing date: 2020-08-19
Publication date: 2022-02-24
Also published as: CN111750990A

Abstract

A time-resolved spectrometer realizing synchronization on the basis of electronics. The time-resolved spectrometer is sequentially provided, along an optical path, with a light source module, a beam combiner, a sample chamber, a light filtering module, a signal probe module and a data acquisition apparatus, wherein the light source module comprises several light sources and drivers. An electronic time delay module generates electric pulse signals with different time sequences to trigger the drivers and control the time sequences of the working of the drivers; the drivers drive the light sources to emit light; multiple paths of light, which have different time delays and are output by the light sources, enter the sample chamber after the multiple paths of light coincide in space by means of the beam combiner; light which reaches a sample first excites the sample, and light which reaches the sample later passes through the sample; after unnecessary light is filtered out by means of the light filtering module, the probe module measures the intensity of transmitted light; and the data acquisition apparatus acquires the measured intensity of transmitted light and records same. Synchronization can be realized by means of electronics. The present invention has a simple structure and is portable, and the stability thereof is greatly improved. By integrating more light sources with different wavelengths, time-resolved spectra of pumping and probing of different wavelengths can easily be obtained.

Description

Electronic synchronization based time-resolved spectrometer

technical field

The invention relates to a spectrometer, in particular to a time-resolved spectrometer based on electronic synchronization.

Background technique

After the material is excited by light, the physical and chemical properties will change with time, which is called the kinetic process. For example, after solar cells, photocatalytic materials, photosensitive molecules, etc. are excited by light, the carriers or molecules in the excited state will relax to the ground state through radiation or non-radiation processes over time. One technique for studying these kinetic processes is time-resolved spectroscopy. Time-resolved spectroscopy, from the time domain, ranges from ultrafast femtosecond and picosecond time, to nanoseconds, microseconds, and then to more macroscopic time scales such as milliseconds and seconds. Conventional time-resolved spectroscopy methods with resolution to picoseconds generally require a picosecond or femtosecond laser light source and a wavelength-tunable laser pulse, and the delay is changed by an optical delay method. The system is large, the stability is poor, and the cost is high. Difficult to maintain.

SUMMARY OF THE INVENTION

Purpose of the invention: The purpose of the present invention is to provide a time-resolved spectrometer based on electronic synchronization, which solves the problems of complex structure and poor stability of the existing picosecond time-resolved spectrometer.

Technical solution: The time-resolved spectrometer based on electronic synchronization according to the present invention is provided with a light source module, a beam combiner, a sample chamber, a filter module, a signal detection module and a data acquisition device in sequence along the optical path, and the light source module includes several A light source and a driver, the driver is electrically connected to the light source, the driver is electrically connected to an electronic delay module, the signal detection module is electrically connected to a data acquisition device, and the electronic delay module generates electrical pulse signals of different timings to trigger each driver Work according to the sequence, each driver drives each light source to emit light, and the multi-path light output by each light source with different delays passes through the beam combiner and enters the sample chamber after spatial overlap. After the filter module filters out the unwanted light, the detection module measures the transmitted light intensity, and the data acquisition device records the transmitted light intensity.

Wherein, the light source module is a free space coupled laser diode, a fiber coupled laser diode or a light emitting diode.

The beam combiner is at least one of a combination of a reflector and a beam combiner, a fiber-coupled beam combiner, a wave plate and a polarization beam splitter.

The filter module is at least one of a filter, a grating and a slit combination, a fiber Bragg grating, a volume Bragg grating and a monochromator.

The signal detection module is any one of photodiode, avalanche photodiode, photomultiplier tube, CCD and CMOS.

The data acquisition device is a PC.

The data acquisition device is electrically connected with the electronic time delay module, and drives the electronic time delay module to work.

Beneficial effects: the present invention can be synchronized by electronics, has a simple and portable structure, and greatly improves the stability. By integrating more light sources with different wavelengths, the time-resolved spectra of pumping and detection with different wavelengths can be obtained relatively easily, and the structure is simple and stable. Enables time-resolved spectroscopic measurements on a wide range of time scales from picoseconds, nanoseconds, microseconds, milliseconds to seconds.

Description of drawings

Schematic diagram of the structure of the present invention.

detailed description

The present invention will be further described below with reference to the accompanying drawings.

As shown in Figure 1, the time-resolved spectrometer based on electronic synchronization of the present invention is sequentially provided with a light source module, a beam combiner, a sample chamber, a filter module, a signal detection module and a data acquisition device along the optical path, and the light source module includes several light sources. and a driver, the driver is electrically connected to the light source, the driver is electrically connected to the electronic delay module, the electronic delay module generates electrical pulse signals of different timings to trigger each driver and control the timing of the driver's work, each driver drives each light source to emit light, and each light source outputs The delayed multi-path light passes through the beam combiner and then enters the sample chamber after spatially overlapping. The light that first reaches the sample excites the sample, and the light that arrives later passes through the sample. After the filter module filters out the unwanted light, the detection module measures the transmission. Light intensity, data acquisition device records transmitted light intensity and time delay. The light source module is a free-space coupled laser diode, a fiber-coupled laser diode, a light emitting diode, and the laser diode is used as the seed light to be amplified by the laser amplifier. For wavelength-tunable lasers, laser diodes are used as seed light to be amplified by laser amplifiers, and then pump nonlinear crystals, such as LiB ₃ O ₅ , β-BaB ₂ O ₄ , LiNbO ₃ and other crystals, to generate harmonic lasers, laser diodes are used as The seed light is amplified by a laser amplifier, and then the material is pumped to produce supercontinuous white light or light in other wavelength bands, such as any one of sapphire crystal, calcium fluoride crystal, water, photonic crystal, and gas; the driver is to drive the light source module to emit light, which can Different currents and different pulse widths are generated, so that the light source module can generate light pulses with different pulse widths and different intensities. It can also have the function of adjusting the temperature of the light source module, and adjust the wavelength emitted by the light source module within a certain range. The start time of the pulse output by the driver is controlled by the rising edge or falling edge of the pulse of the electronic delay module; the pulse width output by the driver can be controlled by its own module. , or determined by the pulse width of the electronic delay module; the electronic delay module can generate electrical pulse signals of different timings to one or more drivers, which are used to trigger different drivers and control the timing of each driver. The electronic delay module outputs pulses The rising edge or falling edge of the trigger module will trigger the output pulse of the driver module. The pulse width of the output pulse of the electronic delay module can also determine the output time and output pulse width of the driver module. The electronic delay module can control the time between the electrical pulses. Time delays, from picoseconds, nanoseconds, microseconds, milliseconds, seconds, and more, and different pulse widths, from picoseconds, nanoseconds, microseconds, milliseconds, seconds, and more; beam combiners are Processing the spatial coincidence of the multiplexed light output by the light source module on the sample, which is one or more of the combination of a reflector and a beam combiner, a fiber-coupled beam combiner, a wave plate and a polarization beam splitter; the sample chamber is used to place the To measure the sample, one or more beams of light generated by the light source module pass through the sample to excite the sample and the sample to absorb and reflect the light; the filter module is to filter out the non-signal light to improve the signal-to-noise ratio. One or more of sheet, grating and slit combination, fiber Bragg grating, volume Bragg grating, and monochromator; the signal detection module is a module for detecting signals, which is a photodiode, avalanche photodiode, photomultiplier tube, CCD, Any of CMOS; the data acquisition device records the delay and records the signal, and can also control what timing the electronic delay module outputs and which driver module to drive, so that one or more light source modules can output one or some specific wavelengths , and record the signal size of the wavelength, and the data acquisition device is a PC.

When the present invention works, the data acquisition device controls the electronic delay module to generate two pulses with a certain delay, and these two pulses trigger two driver modules respectively, so that two light sources generate two pulses with a certain pulse width and a certain delay. beam of light. One of the beams is used as pump light to excite the sample, and the other beam is used as probe light. The signal detection module measures the transmitted light intensity after the detection light passes through the sample under this delay, the data acquisition device records the transmitted light intensity under this delay, and continuously changes the delay of the two beams of light through the electronic delay module, and finally obtains different delays. The current intensity of transmitted light, which is a set of time-resolved absorption spectra. The intensity of reflected light or scattered light of the probe light on the sample can also be measured to obtain a time-resolved spectrum. The data acquisition device can also not control the electronic delay module, but only record the delay. The delay module can change the delay in other ways, such as manually changing the delay between the light pulses of the electronic delay module, and resolving the spectrum at certain times. Among them, it is also possible to generate two or more optical pulses of a certain timing. For example, in time-resolved stimulated Raman spectroscopy, one beam of light is used to pump the sample, and the other two beams of light are used to generate the stimulated Raman process as probe light. By changing the delay between the pump light and the probe light, we can obtain Time-resolved stimulated Raman spectroscopy.

Claims

A time-resolved spectrometer based on electronic synchronization is characterized in that a light source module, a beam combiner, a sample chamber, a filter module, a signal detection module and a data acquisition device are sequentially arranged along the optical path, and the light source module includes a plurality of light sources and a data acquisition device. a driver, the driver is electrically connected to the light source, the driver is electrically connected to the electronic delay module, the signal detection module is electrically connected to the data acquisition device, and the electronic delay module generates electrical pulse signals of different timings to trigger each driver according to the timing sequence Work, each driver drives each light source to emit light, and the multi-path light output by each light source with different delays passes through the beam combiner and enters the sample chamber after spatial overlap. After the module filters out the unwanted light, the detection module measures the transmitted light intensity, and the data acquisition device records the transmitted light intensity.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the light source module is a free space coupled laser diode, a fiber coupled laser diode or a light emitting diode.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the beam combiner is at least one of a reflection mirror and a beam combiner combination, a fiber-coupled beam combiner, a wave plate and a polarization beam splitter combination kind.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the filter module is at least one of a filter, a grating and a slit combination, a fiber Bragg grating, a volume Bragg grating, and a monochromator. A sort of.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the signal detection module is any one of a photodiode, an avalanche photodiode, a photomultiplier tube, a CCD and a CMOS.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the data acquisition device is a PC.
The time-resolved spectrometer based on electronic synchronization according to claim 1, wherein the data acquisition device is electrically connected with the electronic delay module, and drives the electronic delay module to work.