CN115684011A - Nanowire imaging device and group refractive index measuring method - Google Patents

Abstract

The invention provides a nanowire imaging device and a group refractive index measuring method. In the device, a femtosecond laser light source is in optical path connection with a microscope objective so that the microscope objective focuses exciting light of the femtosecond laser light source on a nanowire sample on a sample stage to be used as pump light to excite the nanowire sample, and the nanowire sample generates lasing to radiate emergent light with coherence; and the first beam splitting piece is in optical path connection with the microobjective so as to divide emergent light collected by the microobjective into first light and second light, and the second reflecting mirror used for reflecting the second light is arranged on the sliding component, so that the second reflecting mirror can move along the direction far away from or close to the first beam splitting piece, and further the optical path difference control of the first light and the second light is realized, so that the first imaging device obtains overlapped imaging with different delay times, the signal resolution on a time scale is realized, the detection requirements of optical pulse generation and transmission process are met, and the support is provided for the measurement of the group refractive index.

Description

Nanowire imaging device and method for measuring group refractive index

technical field

The invention relates to the technical field of optical measurement, in particular to a nanowire imaging device, a group refractive index measurement method, a group refractive index measurement device, electronic equipment and a storage medium.

Background technique

With the rapid development of information technology, fields such as optical fiber communication and optical computing are also developing rapidly. In optoelectronic fields such as optical fiber communication and optical computing, it is extremely important to change the group refractive index of the medium and control the generation of slow light. Among them, slow light refers to the physical phenomenon that the group velocity of light waves slows down and is smaller than the speed of light in vacuum when the light wave propagates in the medium. Therefore, in order to better produce the required slow light, it is necessary to measure the group refractive index of the medium.

At present, the group refractive index is calculated by detecting the time delay of light reaching the detector after passing through the medium. However, limited by the pulse width of the used light and the time resolution limit of the detector, this measurement method can only be applied to For the measurement of macroscopic systems, it is difficult to measure the group refractive index of media below the micro-nano scale. For the nanowire system, one end of the nanowire sample is irradiated with a laser beam whose photon energy is higher than the band gap of the material to excite it to generate radiation, and the spectral signal is collected at the other end of the nanowire to extract the measurement group of the cavity mode oscillation information of the nanowire. However, the nanowire imaging device uses continuous light as the excitation light source, which cannot achieve signal resolution on the time scale, so it cannot meet the detection requirements of the optical pulse generation and transmission process, and cannot measure the group refractive index.

Contents of the invention

The present invention provides a nanowire imaging device, a group refractive index measurement method, a group refractive index measurement device, electronic equipment and a storage medium to solve the above-mentioned defects in the prior art and realize group refractive index measurement of nanowires.

The invention provides a nanowire imaging device, comprising: a sample stage, a femtosecond laser light source, a microscope objective lens, an interferometer, and a first imaging device, wherein the interferometer includes a first beam splitter, a first reflector, and a sliding assembly and a second mirror;

The sample stage is used to place the nanowire sample to be measured;

The femtosecond laser light source is optically connected to the microscopic objective lens, the microscopic objective lens is used to focus the excitation light of the femtosecond laser light source on the nanowire sample, and the microscopic objective lens is also used to collect The outgoing light of the nanowire sample, the outgoing light is coherent light emitted after the excitation light causes the nanowire sample to generate lasing;

The first beam splitter is optically connected to the microscope objective lens, and the first beam splitter is used to divide the outgoing light into a first beam of light and a second beam of light;

The first mirror is optically connected to the first beam splitter, and the first mirror is used to reflect the first beam of light to the first beam splitter;

The second reflector is optically connected to the first beam splitter, the second reflector is used to reflect the second beam of light to the first beam splitter, and the second reflector is set In the sliding assembly, the sliding assembly is used to move the second mirror in a direction away from or close to the first beam splitter;

The first imaging device is optically connected to the first beam splitter, so that the reflected first beam of light is transmitted to the first imaging device, and the reflected second beam of light is transmitted to the first imaging device, for the first imaging device to obtain superimposed imaging of the nanowire sample.

A nanowire imaging device provided according to the present invention further includes: a filter;

The first beam splitter is optically connected to the microscope objective lens through the filter;

The microscope objective lens is also used to collect reflected light reflected by the nanowire sample, and the optical filter is used to block the reflected light and transmit the outgoing light.

A nanowire imaging device provided according to the present invention further includes: a spectrometer, a foldable mirror and a controller;

The controller is used to control the foldable mirror, so that the optical filter is connected to the first beam splitter, or the optical filter is connected to the spectrometer;

When the optical filter is connected to the spectrometer in an optical path, the spectrometer is used to detect wavelength information of signal light, and the signal light is light filtered by the optical filter;

The controller is used for adjusting the passing wavelength of the optical filter based on the wavelength information.

According to a nanowire imaging device provided by the present invention, the interferometer further includes: a telephoto lens;

The first imaging device is optically connected to the first beam splitter through the telephoto lens;

The telephoto lens is used for converging the reflected first beam of light and the reflected second beam of light on the first imaging device.

According to a nanowire imaging device provided by the present invention, the second reflecting mirror is a hollow mirror, the hollow mirror includes a first mirror and a second mirror, and the included angle between the first mirror and the second mirror is is 90 degrees;

The first mirror is used to reflect the second beam of light to the second mirror, and the second mirror is used to reflect the second beam of light reflected by the first mirror to the first split beam piece.

A nanowire imaging device provided according to the present invention further includes: a second beam splitter;

The femtosecond laser light source is optically connected to the microscopic objective lens through the second beam splitter, so that the excitation light is transmitted to the microscopic objective lens;

The first beam splitter is optically connected to the microscope objective lens through the second beam splitter, so that the outgoing light is transmitted to the first beam splitter.

A nanowire imaging device provided according to the present invention further includes: an illumination light source and a third beam splitter;

The illumination light source is optically connected to the microscopic objective lens through the third beam splitter, so that the illumination light of the illumination light source is transmitted to the microscopic objective lens, and the microscopic objective lens is also used to illuminating light is focused on the nanowire sample;

The first beam splitter is optically connected to the microscope objective lens through the third beam splitter, so that the outgoing light is transmitted to the first beam splitter.

A nanowire imaging device provided according to the present invention further includes: a second imaging device and a controller;

The second imaging device is optically connected to the microscope objective lens, so that the outgoing light is transmitted to the second imaging device, so that the second imaging device can obtain sample imaging of the nanowire sample;

The sample stage is a movable stage capable of three-dimensional displacement, and the controller is used to control the movement of the sample stage based on the imaging of the sample, so as to focus on the imaging of the nanowire sample.

The present invention also provides a group refractive index measurement method realized by using the nanowire imaging device described in any one of the above, including:

Under the current imaging round, acquire the position information of the sliding assembly, and determine the delay time of the current imaging round based on the position information;

Acquiring overlapping imaging obtained by the first imaging device under the current imaging round;

When the current imaging round is not the last imaging round, control the movement of the sliding assembly to move the sliding assembly to the position of the next imaging round, and use the next imaging round as In the current imaging round, a plurality of overlapping imaging with different delay times is obtained;

Determining interference fringe intensity distribution information based on the plurality of overlapping imaging with different delay times;

Determining a group velocity based on the interference fringe intensity distribution information, the delay times of the overlapping imaging of the plurality of different delay times and the length of the nanowire sample, and determining the group refraction of the nanowire sample based on the group velocity Rate.

According to a group refractive index measurement method provided by the present invention, in the case that the nanowire imaging device includes a filter, a spectrometer and a foldable mirror, when the first imaging device is acquired in the current imaging wheel Overlap image acquired next time, previously also included:

controlling the foldable mirror so that the optical filter is connected to the spectrometer;

adjusting the pass wavelength of the filter based on the wavelength information detected by the spectrometer;

The foldable mirror is controlled so that the optical filter is connected with the first beam splitter.

According to a group refractive index measurement method provided by the present invention, in the case where the nanowire imaging device includes a second imaging device, in the acquisition of the overlapping imaging obtained by the first imaging device in the current imaging round , which previously also included:

acquiring the image of the sample obtained by the second imaging device;

determining a movement pattern based on said imaging of the sample;

Based on the movement pattern, the movement of the sample stage is controlled.

The present invention also provides a group refractive index measurement device realized by using the nanowire imaging device described in any one of the above, including:

An information acquisition module, configured to acquire the position information of the sliding assembly under the current imaging round, and determine the delay time of the current imaging round based on the position information;

an imaging acquisition module, configured to acquire overlapping imaging acquired by the first imaging device in the current imaging round;

An assembly control module, configured to control the movement of the sliding assembly when the current imaging round is not the last imaging round, so as to move the sliding assembly to the position of the next imaging round, and place the The next imaging round is used as the current imaging round, and multiple overlapping imaging with different delay times are obtained;

An information determination module, configured to determine the intensity distribution information of interference fringes based on the overlapping imaging of the plurality of different delay times;

A group refractive index determination module, configured to determine a group velocity based on the intensity distribution information of the interference fringes, the delay time of the overlapping imaging of the plurality of different delay times, and the length of the nanowire sample, and determine the group velocity based on the group velocity The group refractive index of the nanowire sample.

The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor. When the processor executes the program, it realizes the group refractive index as described above. Measurement methods.

The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the method for measuring group refractive index as described in any one of the above-mentioned methods is realized.

In the nanowire imaging device, group refractive index measurement method, group refractive index measurement device, electronic equipment, and storage medium provided by the present invention, the femtosecond laser light source is connected to the microscopic objective lens in an optical path, so that the microscopic objective lens integrates the femtosecond laser light source. The excitation light is focused on the nanowire sample on the sample stage, that is, the excitation light is focused on the surface of the nanowire sample through the microscope objective lens, and used as pump light to excite the nanowire sample, so that the nanowire sample generates lasing and radiates coherent outgoing light; and the first beam splitter is connected to the optical path of the microscopic objective lens to divide the outgoing light collected by the microscopic objective lens into the first light beam and the second light beam, and the light used to reflect the second light beam The second reflection mirror is arranged on the sliding assembly, so that the second reflection mirror can move away from or approach the first beam splitter, thereby realizing the control of the optical path difference between the first beam of light and the second beam of light, so that the first The imaging device obtains overlapping imaging with different delay times, and since the emitted light is a coherent laser, the intensity distribution information of interference fringes can be determined based on multiple overlapping imaging with different delay times, and the detection of optical pulse signal changes on the time scale can be realized , that is, to achieve signal resolution on the time scale and meet the detection requirements of the optical pulse generation and transmission process, thereby providing support for group refractive index measurement.

Description of drawings

In order to more clearly illustrate the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings in the following description are the present invention. For some embodiments of the invention, those skilled in the art can also obtain other drawings based on these drawings without creative effort.

Fig. 1 is one of the structural schematic diagrams of the nanowire imaging device provided by the present invention;

Fig. 2 is the second structural schematic diagram of the nanowire imaging device provided by the present invention;

Fig. 3 is a schematic flow chart of the group refractive index measurement method provided by the present invention;

Fig. 4 is the structural representation of the group refractive index measuring device provided by the present invention;

FIG. 5 is a schematic structural diagram of an electronic device provided by the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention , but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right" , "vertical", "horizontal", "top", "bottom", "inner", "outer" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing this The embodiments and simplified descriptions of the invention do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In the description of the embodiments of the present invention, it should be noted that unless otherwise specified and limited, the terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, Or integrated connection; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary. Those of ordinary skill in the art can understand the specific meanings of the above terms in the embodiments of the present invention in specific situations.

In the embodiments of the present invention, unless otherwise specified and limited, the first feature may be in direct contact with the first feature or the first feature and the second feature may pass through the middle of the second feature. Media indirect contact. Moreover, "above", "above" and "above" the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "beneath" and "beneath" the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the embodiments of the present invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

With the rapid development of information technology, fields such as optical fiber communication and optical computing are also developing rapidly. In the field of optoelectronics such as optical fiber communication and optical computing, it is extremely important to change the group refractive index of the medium and control the generation of slow light, that is, the speed of light control technology has become a research thermoelectric in the field of optoelectronics. Specifically, slowing down the control group speed is conducive to improving the signal delay adjustment efficiency of the optical buffer in all-optical communication and realizing controllable buffering; changing the group refractive index of the medium and controlling the generation of slow light can also improve the optical sensor (such as interference instrument, optical gyroscope, etc.), so slow light technology has important application value in the field of optoelectronics. Among them, slow light refers to the physical phenomenon that the group velocity of light waves slows down and is smaller than the speed of light in vacuum when the light wave propagates in the medium. Therefore, in order to better produce the required slow light, it is necessary to measure the group refractive index of the medium.

At present, the group refractive index is calculated by detecting the time delay of light reaching the detector after passing through the medium. However, limited by the pulse width of the used light and the time resolution limit of the detector, this measurement method can only be applied to For the measurement of macroscopic systems, it is difficult to measure the group refractive index of media below the micro-nano scale. For the nanowire system, one end of the nanowire sample is irradiated with a laser beam whose photon energy is higher than the band gap of the material to excite it to generate radiation, and the spectral signal is collected at the other end of the nanowire to extract the measurement group of the cavity mode oscillation information of the nanowire. However, the nanowire imaging device uses continuous light as the excitation light source, which cannot achieve signal resolution on the time scale, so it cannot meet the detection requirements of the optical pulse generation and transmission process, and cannot measure the group refractive index. Therefore, how to measure the group refractive index of nanowire samples is an urgent problem to be solved.

In view of the above problems, the present invention proposes the following embodiments. In order to measure the group refractive index of the nanowire sample, it is necessary to display the emitted light of the nanowire sample on the imaging plane, and then image the nanowire sample. In order to directly observe the light pulse transmission in the nanowire sample on a time scale, the embodiment of the first aspect of the present invention proposes a nanowire imaging device, which detects the light pulse propagation in the nanowire sample by means of laser coherence analysis, Therefore, the time-scale process of the pulse can be observed intuitively to provide support for the measurement of the group refractive index of the nanowire sample.

Figure 1 is one of the structural schematic diagrams of the nanowire imaging device provided by the present invention. As shown in Figure 1, the nanowire imaging device includes: a sample stage, a femtosecond laser light source, a microscopic objective lens, an interferometer and a first imaging device, The interferometer includes a first beam splitter, a first mirror, a sliding assembly and a second mirror.

The sample stage is used to place the nanowire sample to be measured.

Wherein, the nanowire sample is the medium to be measured for the group refractive index. The nanowire sample is a semiconductor nanowire, so that lasing can be realized in the semiconductor nanowire to radiate coherent laser light.

In one embodiment, the sample stage is a movable stage capable of three-dimensional displacement, so that the nanowire sample can move in three-dimensional space, and then the imaging focus of the nanowire sample can be completed.

The femtosecond laser light source is optically connected to the microscopic objective lens, the microscopic objective lens is used to focus the excitation light of the femtosecond laser light source on the nanowire sample, and the microscopic objective lens is also used to collect The outgoing light of the nanowire sample, the microscope objective lens is also used to collect the outgoing light of the nanowire sample, the outgoing light is emitted after the excitation light causes the nanowire sample to generate lasing sexual light.

Wherein, the femtosecond laser light source is used to generate femtosecond laser, and the excitation light emitted by it is used as pump light to excite the nanowire sample.

It should be noted that the measurement method of the group refractive index of the nanowire sample is calculated using the cavity mode distribution formed by itself. Specifically, the two ends of the nanowire sample form a Fabry-Perot cavity along the axial direction, and the radiated light propagates back and forth in the nanowire sample, and radiates outward through the end surface when it propagates to the end surface. Due to the mode selection effect of the resonant cavity The light emitted from the end face has oscillation characteristics in the wavelength range, and the corresponding group refractive index is obtained by calculating the interval of the oscillation mode in combination with the length of the nanowire. Considering that the radial length of the nanowire sample is close to the wavelength range, the oscillation modes in the nanowire sample are limited, making it difficult to accurately measure the group refractive index by this measurement method. Based on this, the light source of the excitation light is a femtosecond laser light source. Moreover, by exciting the nanowire sample with a femtosecond laser to generate a laser pulse, femtosecond-scale temporal precision detection can be realized, that is, nanoscale spatial precision detection can be realized.

Among them, the outgoing light is the excitation light focused on the surface of the nanowire sample through the microscope objective lens, and the nanowire sample is excited, that is, after the power density reaches the lasing threshold, the nanowire sample realizes lasing and radiates coherent laser light. . The outgoing light is collected by the microscope objective lens and enters the optical path of the nanowire imaging device.

The first beam splitter is optically connected to the microscope objective lens, and the first beam splitter is used to divide the outgoing light into a first beam of light and a second beam of light.

Wherein, the first beam splitter can reflect and transmit the outgoing light. In an embodiment, the first light beam may be transmitted outgoing light, and the second light beam may be reflected outgoing light. In another embodiment, the first light beam may be reflected outgoing light, and the second light beam may be transmitted outgoing light.

The first reflector is optically connected to the first beam splitter, and the first reflector is used to reflect the first beam of light to the first beam splitter.

Specifically, the first beam of light returns to the first beam splitter along the original path through the first reflector.

The second reflector is optically connected to the first beam splitter, the second reflector is used to reflect the second beam of light to the first beam splitter, and the second reflector is set In the sliding assembly, the sliding assembly is used to move the second reflector in a direction away from or close to the first beam splitter.

Specifically, the second beam of light returns to the first beam splitter along the original path through the second reflector.

It can be understood that the control of the optical path difference between the first light beam and the second light beam is realized through the sliding component, so as to detect the change of the optical pulse signal on the time scale, that is, to realize the signal resolution on the time scale, so as to meet the needs of optical pulse generation and Probing requirements during transmission. Moreover, the nanowire sample is excited by a femtosecond laser to generate a laser pulse, combined with the sliding component to adjust the delay time, the femtosecond-scale time precision detection can be realized, that is, the nanoscale space precision detection can be realized.

In one embodiment, the sliding assembly may be an electrically controlled translation stage (time delay line). Specifically, the sliding component is a precision piezoelectric stage, and the step size of each movement can be set according to actual needs, for example, the minimum step size is 50nm, so that a minimum time delay of 0.33fs can be achieved. Based on this, it satisfies the requirement that the interference fringe detection requires precise control of the time delay.

The first imaging device is optically connected to the first beam splitter, so that the reflected first beam of light is transmitted to the first imaging device, and the reflected second beam of light is transmitted to the first imaging device, for the first imaging device to obtain superimposed imaging of the nanowire sample.

Wherein, the first imaging device is used for receiving the optical signal in the optical path to perform spatial imaging. Specifically, the first beam of light and the second beam of light are converged on the photosensitive plane of the first imaging device, so as to realize overlapping of imaging of outgoing light. The first imaging device may be a CMOS (Complementary Metal Oxide Semiconductor, Complementary Metal Oxide Semiconductor) camera, and the embodiment of the present invention does not specifically limit the first imaging device.

Wherein, the overlapping imaging may be that the left end of the nanowire sample overlaps with the left end, or that the right end of the nanowire sample overlaps with the right end. Different overlapping manners can be realized by adjusting the imaging positions of the first beam of light and the second beam of light on the first imaging device, which is not limited in this embodiment of the present invention. Since the outgoing light of the nanowire sample reaches the photosensitive plane of the first imaging device through the first beam of light and the second beam of light simultaneously, coherent fringes with alternating light and dark appear in the overlapping imaging.

In addition, by controlling the position of the sliding assembly, the first imaging device can obtain overlapping imaging with different delay times.

In one embodiment, if the first beam of light is the transmitted outgoing light, and the second beam of light is the reflected outgoing light, then the reflected first beam of light is reflected and transmitted to the first imaging device through the first beam splitter, and the reflected light is transmitted to the first imaging device. The second beam of light is transmitted to the first imaging device through the first beam splitter.

In another embodiment, if the first beam of light is reflected outgoing light, and the second beam of light is transmitted outgoing light, then the reflected first beam of light is transmitted to the first imaging device through the first beam splitter, and the reflected light The second beam of light is reflected by the first beam splitter and transmitted to the first imaging device.

In the nanowire imaging device provided by the embodiment of the present invention, the femtosecond laser light source is connected to the microscopic objective lens in an optical path, so that the microscopic objective lens focuses the excitation light of the femtosecond laser light source on the nanowire sample on the sample stage, that is, the excitation light passes through The microscopic objective lens is focused on the surface of the nanowire sample to excite the nanowire sample as pump light, so that the nanowire sample generates lasing and radiates coherent outgoing light; and the first beam splitter and the microscopic objective lens The optical path is connected to divide the outgoing light collected by the microscope objective lens into the first beam and the second beam, and the second reflector for reflecting the second beam of light is arranged on the sliding assembly, so that the second reflector can Move in a direction away from or close to the first beam splitter, and then realize the control of the optical path difference between the first beam of light and the second beam of light, so that the first imaging device can obtain overlapping imaging with different delay times, and because the outgoing light has Coherent laser, therefore, based on the overlapping imaging of multiple different delay times, the intensity distribution information of interference fringes can be determined, and the detection of optical pulse signal changes on the time scale can be realized, that is, the signal resolution on the time scale can be realized, and the generation and transmission of optical pulses can be satisfied. The probing needs of the process, thus providing support for group refractive index measurements.

Based on the above embodiments, the nanowire imaging device further includes: a filter.

The first beam splitter is optically connected to the microscope objective lens through the optical filter.

Wherein, the optical filter is used to realize the wavelength selection of the emitted light of the nanowire sample, that is, to filter the optical signal. Specifically, the optical filter has a pass wavelength parameter, and only when the wavelength of the optical signal is within the pass wavelength of the filter, the optical signal is allowed to pass through the filter, otherwise the optical signal is blocked. Based on this, the light signals other than the outgoing light of the nanowire sample can be blocked, and only the outgoing light is allowed to pass through, thereby ensuring the accuracy of overlapping imaging. Furthermore, the pass wavelength of the optical filter can be updated, so that the wavelength to be detected can be selected according to actual needs.

In one embodiment, the filter is a bandpass filter. In another embodiment, the optical filter is composed of a combination of a low-pass filter and a high-pass filter.

Specifically, one end of the optical filter is connected to the optical path of the first beam splitter, and the other end of the optical filter is connected to the optical path of the microscope objective lens.

The microscope objective lens is also used to collect reflected light reflected by the nanowire sample, and the optical filter is used to block the reflected light and transmit the outgoing light.

Wherein, the reflected light reflected by the nanowire sample is the light reflected by the excitation light focused on the nanowire sample.

In one embodiment, the microscope objective lens is also used to collect the reflected light reflected by the sample stage (such as the substrate), and the optical filter is also used to block the reflected light reflected by the sample stage. In an embodiment, the filter is also used to block the light split by the excitation light after passing through the second beam splitter. In an embodiment, the filter is also used to block the light divided by the illumination light of the illumination source after passing through the third beam splitter.

In one embodiment, the optical filter is connected to the microscope objective lens through the second beam splitter. In one embodiment, the optical filter is connected to the microscope objective lens through the third beam splitter. In one embodiment, the filter is optically connected to the first beam splitter through a foldable mirror.

In the nanowire imaging device provided by the embodiment of the present invention, by setting a filter between the first beam splitter and the optical path of the microscope objective lens, it can ensure that other optical signals except the outgoing light are blocked, and only the outgoing light is allowed to pass through. Ensures accurate overlay imaging, ultimately improving the accuracy of group refractive index measurements.

Based on any of the above embodiments, the nanowire imaging device further includes: a spectrometer, a foldable mirror and a controller.

The controller is used to control the foldable mirror, so that the optical filter is connected to the first beam splitter, or the optical filter is connected to the spectrometer.

Wherein, the spectrometer is used to determine the spectral information of the collected optical signal. Specifically, the optical signal enters the spectrometer for spectral detection to determine the wavelength information.

Wherein, the foldable mirror can be controlled to be in two states. The first state: the optical filter is connected to the optical path of the first beam splitter, and the optical filter is disconnected from the optical path of the spectrometer. The second state: the optical filter is disconnected from the optical path of the first beam splitter, and the optical filter is connected to the optical path of the spectrometer.

When the optical filter is connected to the spectrometer by an optical path, the spectrometer is used to detect wavelength information of signal light, and the signal light is light filtered by the optical filter.

The controller is used for adjusting the passing wavelength of the optical filter based on the wavelength information.

Specifically, based on the wavelength information, the passing wavelength of the optical filter is continuously changed until the wavelength information meets the requirements, and the changing of the passing wavelength of the optical filter is stopped, so that the optical filter only passes the outgoing light as much as possible. Further, after the pass wavelength of the optical filter is determined, the foldable mirror is controlled to connect the optical filter with the first beam splitter, so that the outgoing light enters the interferometer.

In one embodiment, the foldable mirror is optically connected to the spectrometer through the fourth beam splitter.

In the nanowire imaging device provided by the embodiment of the present invention, when the pass wavelength of the optical filter needs to be updated, the foldable mirror can be controlled so that the optical filter is connected to the optical path of the spectrometer, so that the signal filtered by the optical filter can be detected by the spectrometer The wavelength information of the light, and then adjust the pass wavelength of the filter based on the wavelength information, so that the wavelength to be detected can be selected, and then it can ensure that other optical signals except the outgoing light are blocked, and only the outgoing light is allowed to pass, thus ensuring overlapping imaging accuracy, and ultimately improve the accuracy of group refractive index measurements.

Based on any of the above embodiments, the interferometer further includes: a telephoto lens.

The first imaging device is optically connected to the first beam splitter through the telephoto lens.

Wherein, the telephoto lens is used for converging the input optical signal. Specifically, the telephoto lens can realize the reciprocal transformation of the object phase between the real space phase and the Fourier phase.

The telephoto lens is used for converging the reflected first beam of light and the reflected second beam of light on the first imaging device.

Specifically, the two beams of light respectively reflected and transmitted by the first beam splitter are converged on the photosensitive plane of the first imaging device through the telephoto lens, so as to realize the overlapping of imaging of the outgoing light.

In the nanowire imaging device provided in the embodiment of the present invention, a telephoto lens is arranged in the middle of the optical path between the first imaging device and the first beam splitter, so as to converge the reflected first beam of light and the reflected second beam of light on the first The imaging device can better realize the overlapping of imaging of outgoing light, further improve the accuracy of overlapping imaging, and finally further improve the accuracy of group refractive index measurement.

Based on any of the above embodiments, the second reflecting mirror is a hollow mirror, the hollow mirror includes a first mirror and a second mirror, and the angle between the first mirror and the second mirror is 90 degrees; The first mirror is used to reflect the second beam of light to the second mirror, and the second mirror is used to reflect the second beam of light reflected by the first mirror to the first beam splitter .

Wherein, the first mirror is a reflecting mirror, and the mirror surface of the first mirror faces the second beam of light for reflecting the second beam of light. The second mirror is a reflecting mirror, and the mirror surface of the second mirror faces the second beam of light for reflecting the second beam of light.

In a specific embodiment, the incident angle between the second light beam and the mirror surface of the first mirror is 45 degrees, so that the second light beam reflected by the hollow mirror is reflected back to the first beam splitter.

In the nanowire imaging device provided by the embodiment of the present invention, the second reflector is a hollow mirror, and the angle between the first mirror and the second mirror is 90 degrees, so as to ensure that the second beam of light reflected by the first mirror is consistent with the incident light on the first mirror. The optical path of the second beam of light from a mirror is parallel, so as to ensure that the position of the optical signal does not shake, that is, only a time delay is generated, which improves the accuracy of overlapping imaging, and finally further improves the accuracy of group refractive index measurement.

Based on any of the above embodiments, the nanowire imaging device further includes: a second beam splitter.

The femtosecond laser light source is optically connected to the microscopic objective lens through the second beam splitter, so that the excitation light is transmitted to the microscopic objective lens.

The first beam splitter is optically connected to the microscope objective lens through the second beam splitter, so that the outgoing light is transmitted to the first beam splitter.

Wherein, the second beam splitter can reflect and transmit the excitation light of the femtosecond laser light source. In one embodiment, the second beam splitter reflects the excitation light to the microscope objective lens and transmits the outgoing light. In another embodiment, the second beam splitter transmits the excitation light to the microscope objective lens and reflects the outgoing light.

One end of the second beam splitter is connected to the optical path of the microscope objective lens, the other end of the second beam splitter is connected to the optical path of the first beam splitter, and the second beam splitter is connected to the optical path of the first beam splitter. In an embodiment, the second beam splitter is optically connected to the first beam splitter through an optical filter, and based on this, the optical filter can block the excitation light passing through the second beam splitter. In an embodiment, the second beam splitter is optically connected to the first beam splitter through the third beam splitter.

In the nanowire imaging device provided by the embodiment of the present invention, a second beam splitter is arranged between the optical path between the femtosecond laser light source and the microscopic objective lens, so that the excitation light can be transmitted to the microscopic objective lens, and the outgoing light can be transmitted to the first beam splitter. In order to better manage the optical path, ensure the accuracy of overlapping imaging, and finally further improve the accuracy of group refractive index measurement.

Based on any of the above embodiments, the nanowire imaging device further includes: an illumination light source and a third beam splitter.

The illumination light source is optically connected to the microscopic objective lens through the third beam splitter, so that the illumination light of the illumination light source is transmitted to the microscopic objective lens, and the microscopic objective lens is also used to Illumination light is focused on the nanowire sample.

The first beam splitter is optically connected to the microscope objective lens through the third beam splitter, so that the outgoing light is transmitted to the first beam splitter.

Wherein, the illumination light source is used to provide illumination for the nanowire sample. The illumination light source is preferably a white light source, and of course it can also be a light source of other colors.

Wherein, the third beam splitter can reflect and transmit the illumination light of the illumination source. In one embodiment, the third beam splitter reflects the illumination light to the microscope objective lens and transmits the outgoing light. In another embodiment, the third beam splitter transmits the illumination light to the microscope objective lens and reflects the outgoing light.

One end of the third beam splitter is connected to the optical path of the microscope objective lens, the other end of the third beam splitter is connected to the optical path of the first beam splitter, and the third beam splitter is connected to the first beam splitter in the optical path. In an embodiment, the third beam splitter is optically connected to the first beam splitter through a filter, and based on this, the filter can block the illumination light passing through the third beam splitter. In an embodiment, the third beam splitter is optically connected to the microscope objective lens through the second beam splitter. In an embodiment, the third beam splitter is optically connected to the first beam splitter through the second beam splitter.

The nanowire imaging device provided by the embodiment of the present invention is provided with an illumination source to provide illumination for the nanowire sample, thereby ensuring the definition of overlapping imaging, and finally further improving the accuracy of group refractive index measurement; and in the relationship between the illumination source and the microscope objective The third beam splitter is set in the middle of the optical path, which can transmit the illumination light to the microscope objective lens and the outgoing light to the first beam splitter, so as to better manage the optical path, ensure the accuracy of overlapping imaging, and ultimately further improve Accuracy of group index measurements.

Based on any of the above embodiments, the nanowire imaging device further includes: a second imaging device and a controller.

The second imaging device is optically connected to the microscope objective lens, so that the emitted light is transmitted to the second imaging device, so that the second imaging device can obtain a sample image of the nanowire sample.

The sample stage is a movable stage capable of three-dimensional displacement, and the controller is used to control the movement of the sample stage based on the imaging of the sample, so as to focus on the imaging of the nanowire sample.

Wherein, the second imaging device is used for receiving the optical signal in the optical path to perform spatial imaging. Specifically, the outgoing light is collected on the photosensitive plane of the second imaging device to realize imaging of the outgoing light. The second imaging device may be a CMOS camera, and the embodiment of the present invention does not specifically limit the second imaging device.

In one embodiment, the second imaging device is optically connected to the microscope objective lens through a filter. In one embodiment, the second imaging device is optically connected to the microscope objective lens through the second beam splitter. In an embodiment, the second imaging device is optically connected with the microscope objective lens through the third beam splitter. In one embodiment, the second imaging device is optically connected to the microscope objective lens through a foldable mirror.

In an embodiment, the nanowire imaging device further includes: a fourth beam splitter and a spectrometer. The second imaging device is optically connected with the microscopic objective lens through the fourth beam splitter, so that the outgoing light is transmitted to the second imaging device, and the spectrometer is connected with the optical path through the fourth beam splitter with the microscopic objective lens, so that the outgoing light is transmitted to the second imaging device. spectrometer.

The fourth beam splitter can reflect and transmit the outgoing light. In an embodiment, the fourth beam splitter reflects the outgoing light to the second imaging device, and transmits the outgoing light to the spectrometer. In another embodiment, the fourth beam splitter transmits the outgoing light to the second imaging device, and reflects the outgoing light to the spectrometer.

One end of the fourth beam splitter is connected to the optical path of the microscope objective lens, the other end of the fourth beam splitter is connected to the optical path of the second imaging device, and the third end of the fourth beam splitter is connected to the optical path of the spectrometer. In an embodiment, the fourth beam splitter is optically connected to the microscope objective lens through a filter. In an embodiment, the fourth beam splitter is optically connected to the microscope objective lens through the second beam splitter. In one embodiment, the fourth beam splitter is optically connected to the microscope objective lens through the third beam splitter. In one embodiment, the fourth beam splitter is optically connected to the microscope objective lens through a foldable mirror.

It can be understood that setting the fourth beam splitter can better manage the optical path, ensure the accuracy of overlapping imaging, and finally further improve the accuracy of group refractive index measurement.

In the nanowire imaging device provided by the embodiment of the present invention, by setting the second imaging device, the emitted light of the nanowire sample is imaged, thereby controlling the sample stage to move in three-dimensional space based on the sample imaging, so as to realize the imaging focus of the nanowire sample, ensuring The clarity and accuracy of overlay imaging ultimately further improves the accuracy of group refractive index measurements.

To facilitate the understanding of the above embodiments, it should be noted that the propagation of light pulses and the detection of coherent fringes require the nanowire sample to be able to emit coherent laser light. The end face of the nanowire sample structure and the external medium (usually air) form a Fabry-Perot resonant cavity, which provides an effective gain medium, low-loss waveguide and strong lateral optical confinement for the axial mode. Using femtosecond laser pulses as excitation light, coherent lasing light pulses are generated in the nanowire sample after the excitation power reaches the lasing threshold of the nanowire sample. When the laser light pulse reaches the end face of the nanowire, part of it is emitted through the end face, and the transmitted signal is collected by the first imaging device through the nanowire imaging device; the other part is reflected by the end face and propagates in the opposite direction in the nanowire sample, reaching the other end. Transmission and reflection continue to occur at the end face until the pulse intensity is completely decayed.

In order to facilitate understanding of the above-mentioned embodiments, a specific embodiment is used for description here. With reference to Fig. 2, Fig. 2 is the second structural representation of the nanowire imaging device provided by the present invention, as shown in Fig. 2, the nanowire imaging device comprises a femtosecond laser (femtosecond laser light source), a microscopic objective lens, an interferometer, a camera 2 (first imaging device), filter, spectrometer, foldable mirror, lens (telephoto lens), beam splitter 1 (second beam splitter), white light source (illumination light source), beam splitter 2 ( The third beam splitter), camera 1 (second imaging device), beam splitter 3 (fourth beam splitter), the interferometer includes beam splitter 4 (first beam splitter), mirror (first mirror ), an electronically controlled stage (slide assembly) and a hollow mirror (second mirror). The microscopic objective lens is used to focus the excitation light of the femtosecond laser on the nanowire sample, and the microscopic objective lens is also used to collect the outgoing light of the nanowire sample. The illumination light of the white light source is transmitted to the beam splitter 2 through the optical fiber. The electronically controlled displacement stage can move left and right, so that the hollow mirror moves away from or close to the beam splitter 4 . The controller can be a computer, so that the interference intensity signal detected by the camera 2 is analyzed by the computer, and then combined with the optical path corresponding to the electronically controlled displacement stage, the interference intensity signal containing time information is obtained.

Based on the above nanowire imaging device, the present invention also proposes a group refractive index measurement method, which is realized by using the above nanowire imaging device. The execution subject of the group refractive index measurement method may be the controller of the nanowire imaging device, or another terminal device, such as a notebook computer, a desktop computer, a tablet computer, a smart phone, an embedded system, a server, etc., the present invention The embodiment does not limit this.

Fig. 3 is a schematic flow chart of the method for measuring the group refractive index provided by the present invention. As shown in Fig. 3, the method for measuring the group refractive index includes:

Step 310, under the current imaging round, acquire the position information of the sliding assembly, and determine the delay time of the current imaging round based on the position information.

It should be noted that, in order to obtain overlapping imaging with different delay times, multiple imaging rounds need to be performed, and the positions of the sliding components under each imaging round are different. Based on this, the delay times under each imaging round are different, so , the delay time of each imaging round needs to be obtained.

Specifically, the delay time corresponding to the location information may be determined based on the location-time mapping relationship. The corresponding delay time may also be obtained through formula calculation based on the location information. This embodiment of the present invention does not limit it.

Step 320, acquiring overlapping imaging obtained by the first imaging device in the current imaging round.

The superimposed imaging can be obtained by the nanowire imaging device of any of the above embodiments, and the specific process of obtaining the superimposed imaging can refer to the above embodiments, and will not be repeated here.

Step 330, in the case that the current imaging round is not the last imaging round, control the movement of the sliding assembly to move the sliding assembly to the position of the next imaging round, and place the next imaging round A round is used as the current imaging round, and a plurality of overlapping imaging with different delay times is obtained.

It can be understood that, after each imaging round, the movement of the sliding assembly is controlled so that the positions of the sliding assembly in each imaging round are different, thereby obtaining overlapping imaging of different imaging rounds, that is, overlapping imaging of different delay times .

Step 340, based on the multiple overlapping images with different delay times, determine interference fringe intensity distribution information.

Specifically, the interference fringe intensity distribution information is extracted from multiple overlapping images with different delay times.

Step 350, determine the group velocity based on the intensity distribution information of the interference fringes, the delay times of the overlapping imaging of the plurality of different delay times, and the length of the nanowire sample, and determine the nanowire sample based on the group velocity The group refractive index of .

Specifically, based on the intensity distribution information of the interference fringes, the amplitude corresponding to the interference fringes is obtained by means of Fourier transform, which represents the coherence intensity of the two light pulses at this time. Since the light pulse emitted by the nanowire sample is reflected back and forth multiple times in the reflective cavity formed by the nanowire itself, it appears as the emission of multiple light pulses on the time scale, and multiple pulse signals with symmetrical distribution can be observed from the delay time scale The peak corresponds to the coherent intensity distribution of the coherent optical pulse at zero time and the pulse at any time. By fitting the peak value and intensity distribution of the pulse peak, the dynamic process of the laser pulse moving in the nanowire sample can be obtained, and then combined with the length of the nanowire to calculate the propagation speed of the laser pulse generated by the femtosecond laser excitation in the nanowire sample, That is, the group velocity, and then determine the group refractive index of the nanowire sample based on the group velocity and the speed of light.

It should be noted that, using the real-space imaging detection of laser light pulses in the nanowire sample, the spatial overlaps on the detection plane of the imaging device. The optical path difference between the two paths of light in the interferometer is controlled by adjusting the movement of the sliding component, and the coherence change of the light pulse is collected to obtain the distribution of the interference signal on the time scale. The intensity of the coherent fringe at the corresponding delay time (that is, at a certain optical path difference position) is extracted from the image by Fourier transform operation. The intensity and time distribution of multiple pulse peaks are extracted and fitted to the time distribution of coherent intensity, and the time when the laser pulse reaches the endpoint during multiple propagations in the nanowire is obtained.

In the group refractive index measurement method provided by the embodiment of the present invention, the femtosecond laser light source is connected to the microscopic objective lens in an optical path, so that the microscopic objective lens focuses the excitation light of the femtosecond laser light source on the nanowire sample on the sample stage, that is, the excitation light The nanowire sample is focused on the surface of the nanowire sample by the microscope objective lens to excite the nanowire sample as pump light, so that the nanowire sample generates lasing and radiates coherent outgoing light; and the first beam splitter and the display The micro-objective lens is connected to the optical path to divide the outgoing light collected by the micro-objective lens into a first beam of light and a second beam of light, and a second reflector for reflecting the second beam of light is arranged on the sliding assembly, so that the second reflection The mirror can move in a direction away from or close to the first beam splitter, thereby realizing the control of the optical path difference between the first beam and the second beam, that is, the position information of the sliding component can be acquired under the current imaging round, and Determining the delay time of the current imaging round based on the position information, acquiring the overlapping imaging obtained by the first imaging device under the current imaging round, and controlling the movement of the sliding assembly when the current imaging round is not the last imaging round, so as to Move the sliding assembly to the position of the next imaging round, and use the next imaging round as the current imaging round to obtain multiple overlapping imaging with different delay times, and since the outgoing light is a coherent laser, therefore, Based on the overlapping imaging of multiple different delay times, the intensity distribution information of interference fringes can be determined, and the detection of optical pulse signal changes on the time scale can be realized, that is, the signal resolution on the time scale can be realized, and the detection requirements of the optical pulse generation and transmission process can be met. Based on the intensity distribution information of interference fringes, the delay time of multiple overlapping imaging with different delay times and the length of the nanowire sample, determine the group velocity, and determine the group refractive index of the nanowire sample based on the group velocity, and finally realize the group refraction of the nanowire sample rate measurement.

Based on any of the above embodiments, when the nanowire imaging device includes a filter, a spectrometer and a foldable mirror, before the above step 320, the method further includes:

controlling the foldable mirror so that the optical filter is connected to the spectrometer;

adjusting the pass wavelength of the filter based on the wavelength information detected by the spectrometer;

The foldable mirror is controlled so that the optical filter is connected with the first beam splitter.

Specifically, based on the wavelength information, the passing wavelength of the optical filter is continuously changed until the wavelength information meets the requirements, and the changing of the passing wavelength of the optical filter is stopped, so that the optical filter only passes the outgoing light as much as possible. After the pass wavelength of the optical filter is determined, the foldable mirror is controlled to connect the optical filter with the first beam splitter, so that the outgoing light enters the interferometer.

In the group refractive index measurement method provided by the embodiment of the present invention, when the pass wavelength of the filter needs to be updated, the foldable mirror can be controlled so that the filter is connected to the optical path of the spectrometer, so that the spectrometer can detect the The wavelength information of the signal light, and then adjust the pass wavelength of the filter based on the wavelength information, so that the wavelength to be detected can be selected, and then it can ensure that other optical signals except the outgoing light are blocked, and only the outgoing light is allowed to pass, thereby ensuring overlap Imaging accuracy, ultimately improving the accuracy of group refractive index measurements.

Based on any of the above embodiments, when the nanowire imaging device includes a second imaging device, before the above step 320, the method further includes:

acquiring the image of the sample obtained by the second imaging device;

determining a movement pattern based on said imaging of the sample;

Based on the movement pattern, the movement of the sample stage is controlled.

The sample imaging can be obtained by the nanowire imaging device of any of the above embodiments, and the specific process of obtaining the sample imaging can refer to the above embodiments, and will not be repeated here.

Specifically, the resolution of the sample imaging is determined, and then the movement mode is determined based on the resolution, so that based on the movement mode, the sample stage is controlled to move in three-dimensional space to focus the imaging of the nanowire sample.

In the nanowire imaging device provided by the embodiment of the present invention, by setting the second imaging device, the emitted light of the nanowire sample is imaged, thereby controlling the sample stage to move in three-dimensional space based on the sample imaging, so as to realize the imaging focus of the nanowire sample, ensuring The clarity and accuracy of overlay imaging ultimately further improves the accuracy of group refractive index measurements.

In the actual application process, pure optical non-destructive detection is realized by collecting signals through optical excitation and imaging devices, avoiding the restriction of the medium environment in which the nanowire sample is located, and is suitable for real-time detection of on-chip integrated devices.

The group refractive index measurement device provided by the present invention is described below, and the group refractive index measurement device described below and the group refractive index measurement method described above can be referred to in correspondence.

Fig. 4 is a schematic structural diagram of a group refractive index measuring device provided by the present invention, as shown in Fig. 4, the group refractive index measuring device includes:

An information acquisition module 410, configured to acquire the position information of the sliding assembly under the current imaging round, and determine the delay time of the current imaging round based on the position information;

An imaging acquisition module 420, configured to acquire overlapping imaging acquired by the first imaging device in the current imaging round;

The component control module 430 is configured to control the movement of the sliding component when the current imaging round is not the last imaging round, so as to move the sliding component to the position of the next imaging round, and set the The next imaging round is used as the current imaging round, and a plurality of overlapping imaging with different delay times is obtained;

An information determination module 440, configured to determine the interference fringe intensity distribution information based on the overlapping imaging of the plurality of different delay times;

A group refractive index determination module 450, configured to determine a group velocity based on the intensity distribution information of the interference fringes, the delay time of the overlapping imaging of the plurality of different delay times, and the length of the nanowire sample, and based on the group velocity Determining the group refractive index of the nanowire sample.

In the group refractive index measurement device provided by the embodiment of the present invention, the femtosecond laser light source is connected to the microscopic objective lens in an optical path, so that the microscopic objective lens focuses the excitation light of the femtosecond laser light source on the nanowire sample on the sample stage, that is, the excitation light Focusing on the surface of the nanowire sample through the microscope objective lens, it is used as pump light to excite the nanowire sample, so that the nanowire sample generates lasing and radiates coherent outgoing light; and the first beam splitter and the microscope The objective lens is connected on the optical path to divide the outgoing light collected by the microscopic objective lens into a first beam of light and a second beam of light, and a second reflector for reflecting the second beam of light is arranged on the sliding assembly, so that the second reflector It can move in the direction away from or close to the first beam splitter, and then realize the control of the optical path difference between the first beam and the second beam, that is, the position information of the sliding component can be acquired under the current imaging round, and based on The position information determines the delay time of the current imaging round, obtains the overlapping imaging obtained by the first imaging device under the current imaging round, and controls the movement of the sliding assembly when the current imaging round is not the last imaging round to move The sliding assembly is moved to the position of the next imaging round, and the next imaging round is used as the current imaging round to obtain multiple overlapping imaging with different delay times, and since the outgoing light is a coherent laser, based on The overlapping imaging of multiple different delay times can determine the intensity distribution information of interference fringes, realize the detection of optical pulse signal changes on the time scale, that is, realize the signal resolution on the time scale, and meet the detection requirements of the optical pulse generation and transmission process, that is, it can be based on Interference fringe intensity distribution information, delay time of overlapping imaging with different delay times and the length of the nanowire sample, determine the group velocity, and determine the group refractive index of the nanowire sample based on the group velocity, and finally realize the group refractive index of the nanowire sample Measurement.

Based on any of the above embodiments, when the nanowire imaging device includes a filter, a spectrometer and a foldable mirror, the group of refractive index measurement devices further includes:

The foldable mirror control module is used to control the foldable mirror so that the optical filter is connected to the spectrometer;

a wavelength adjustment module, configured to adjust the passing wavelength of the filter based on the wavelength information detected by the spectrometer;

The foldable mirror control module is used to control the foldable mirror so that the optical filter is connected to the first beam splitter.

Based on any of the above embodiments, when the nanowire imaging device includes a second imaging device, the group of refractive index measurement devices further includes:

a sample acquisition module, configured to acquire the image of the sample obtained by the second imaging device;

a mode determination module, configured to determine a movement mode based on the sample imaging;

The sample stage control module is used to control the movement of the sample stage based on the moving manner.

FIG. 5 illustrates a schematic diagram of the physical structure of an electronic device. As shown in FIG. 5, the electronic device may include: a processor (processor) 510, a communication interface (Communications Interface) 520, a memory (memory) 530 and a communication bus 540, Wherein, the processor 510 , the communication interface 520 , and the memory 530 communicate with each other through the communication bus 540 . The processor 510 may call the logic instructions in the memory 530 to execute the method for measuring the group refractive index, the method comprising: obtaining the position information of the sliding assembly in the current imaging round, and determining the current position information based on the position information. The delay time of an imaging round; acquiring the overlapping imaging obtained by the first imaging device under the current imaging round; in the case that the current imaging round is not the last imaging round, controlling the sliding assembly move to move the sliding assembly to the position of the next imaging round, and use the next imaging round as the current imaging round to obtain multiple overlapping imaging with different delay times; based on the multiple different Delay time overlapping imaging, determine interference fringe intensity distribution information; based on the interference fringe intensity distribution information, the delay time of the overlapping imaging of multiple different delay times and the length of the nanowire sample, determine the group velocity, and based on The group velocity determines the group refractive index of the nanowire sample.

In addition, the above logic instructions in the memory 530 may be implemented in the form of software function units and be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

On the other hand, the present invention also provides a computer program product. The computer program product includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can Executing the group refractive index measurement method provided by the above methods, the method includes: under the current imaging round, acquiring the position information of the sliding assembly, and determining the delay time of the current imaging round based on the position information; Acquiring overlapping imaging obtained by the first imaging device under the current imaging round; if the current imaging round is not the last imaging round, controlling the movement of the sliding assembly to move the sliding component to the position of the next imaging round, and use the next imaging round as the current imaging round to obtain multiple overlapping imaging with different delay times; based on the multiple overlapping imaging with different delay times, determine Interference fringe intensity distribution information; based on the interference fringe intensity distribution information, the delay time of the overlapping imaging of the plurality of different delay times and the length of the nanowire sample, determine the group velocity, and determine the group velocity based on the group velocity Group refractive index of nanowire samples.

In yet another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it is implemented to perform the method for measuring the group refractive index provided by the above-mentioned methods, the method The method includes: obtaining the position information of the sliding assembly under the current imaging round, and determining the delay time of the current imaging round based on the position information; obtaining the first imaging device under the current imaging round Obtained overlapping imaging; in the case that the current imaging round is not the last imaging round, control the movement of the sliding assembly to move the sliding assembly to the position of the next imaging round, and place the next imaging round An imaging round is used as the current imaging round, and multiple overlapping imaging with different delay times is obtained; based on the multiple overlapping imaging with different delay times, interference fringe intensity distribution information is determined; based on the interference fringe intensity distribution information, The delay times of the overlapping imaging of the plurality of different delay times and the length of the nanowire sample determine a group velocity, and determine a group refractive index of the nanowire sample based on the group velocity.

The device embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed to multiple network elements. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. It can be understood and implemented by those skilled in the art without any creative efforts.

Through the above description of the implementations, those skilled in the art can clearly understand that each implementation can be implemented by means of software plus a necessary general hardware platform, and of course also by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic discs, optical discs, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (14)

1. A nanowire imaging device, comprising: the interferometer comprises a first beam splitting sheet, a first reflecting mirror, a sliding assembly and a second reflecting mirror;

the sample table is used for placing a nanowire sample to be measured;

the femtosecond laser light source is in optical path connection with the microscope objective, the microscope objective is used for focusing exciting light of the femtosecond laser light source on the nanowire sample, the microscope objective is also used for collecting emergent light of the nanowire sample, and the emergent light is coherent light emitted after the exciting light enables the nanowire sample to generate radiation;

the first beam splitting sheet is in optical path connection with the microscope objective and is used for dividing the emergent light into a first beam of light and a second beam of light;

the first reflector is in optical path connection with the first beam splitting sheet, and the first reflector is used for reflecting the first beam of light to the first beam splitting sheet;

the second reflector is in optical path connection with the first beam splitting sheet, the second reflector is used for reflecting the second beam of light to the first beam splitting sheet, the second reflector is arranged on the sliding assembly, and the sliding assembly is used for enabling the second reflector to move along the direction far away from or close to the first beam splitting sheet;

the first imaging device is in optical path connection with the first beam splitting sheet, so that the reflected first beam of light is transmitted to the first imaging device, and the reflected second beam of light is transmitted to the first imaging device, so that the first imaging device can obtain overlapped imaging of the nanowire sample.

2. The nanowire imaging device of claim 1, further comprising: an optical filter;

the first beam splitting sheet is in optical path connection with the microscope objective through the optical filter;

the micro objective is also used for collecting reflected light reflected by the nanowire sample, and the optical filter is used for blocking the reflected light and transmitting the emergent light.

3. The nanowire imaging device of claim 2, further comprising: the spectrometer, the turnover mirror and the controller;

the controller is used for controlling the foldable mirror so that the optical filter is in optical path connection with the first beam splitting sheet or the optical filter is in optical path connection with the spectrometer;

under the condition that the optical filter is in optical path connection with the spectrometer, the spectrometer is used for detecting wavelength information of signal light, and the signal light is light filtered by the optical filter;

the controller is used for adjusting the passing wavelength of the optical filter based on the wavelength information.

4. The nanowire imaging device of claim 1, wherein the interferometer further comprises: a telephoto lens;

the first imaging device is in optical path connection with the first beam splitting sheet through the long-focus lens;

the telephoto lens is used for converging the reflected first beam of light and the reflected second beam of light to the first imaging device.

5. The nanowire imaging device of claim 1, wherein the second mirror is a hollow mirror comprising a first mirror and a second mirror, the first mirror having a mirror surface angle of 90 degrees with respect to the second mirror;

the first mirror is configured to reflect the second beam of light to the second mirror, and the second mirror is configured to reflect the second beam of light reflected by the first mirror to the first beam splitting sheet.

6. The nanowire imaging device of claim 1, further comprising: a second beam splitting sheet;

the femtosecond laser light source is in optical path connection with the microscope objective through the second beam splitting sheet so as to transmit the exciting light to the microscope objective;

the first beam splitting sheet is in optical path connection with the microscope objective through the second beam splitting sheet so that the emergent light is transmitted to the first beam splitting sheet.

7. The nanowire imaging device of claim 1, further comprising: an illumination light source and a third beam splitter;

the illumination light source is in optical path connection with the microscope objective through the third beam splitting sheet so that illumination light of the illumination light source is transmitted to the microscope objective, and the microscope objective is further used for focusing the illumination light on the nanowire sample;

the first beam splitting sheet is in optical path connection with the microscope objective through the third beam splitting sheet so that the emergent light is transmitted to the first beam splitting sheet.

8. The nanowire imaging device of claim 1, further comprising: a second imaging device and a controller;

the second imaging device is in optical path connection with the microscope objective so that the emergent light is transmitted to the second imaging device to enable the second imaging device to obtain sample imaging of the nanowire sample;

the sample stage is a three-dimensional displaceable moving stage, and the controller is used for controlling the sample stage to move based on the sample imaging so as to perform imaging focusing on the nanowire sample.

9. A method of group refractive index measurement using the nanowire imaging device of any one of claims 1-8, comprising:

acquiring position information of the sliding assembly in a current imaging round, and determining delay time of the current imaging round based on the position information;

acquiring overlapped imaging obtained by the first imaging device under the current imaging round;

under the condition that the current imaging round is not the last imaging round, controlling the sliding assembly to move so as to move the sliding assembly to the position of the next imaging round, and taking the next imaging round as the current imaging round to obtain a plurality of overlapped images with different delay times;

determining interference fringe intensity distribution information based on the plurality of overlapping images of different delay times;

determining a group velocity based on the interference fringe intensity distribution information, the delay time for overlay imaging of the plurality of different delay times, and the length of the nanowire sample, and determining a group refractive index of the nanowire sample based on the group velocity.

10. The group refractive index measurement method according to claim 9, wherein in a case where the nanowire imaging device includes a filter, a spectrometer, and a tiltable mirror, before the acquiring the overlay images obtained by the first imaging device in the current imaging round, further comprises:

controlling the foldable mirror to enable the optical filter to be in optical path connection with the spectrometer;

adjusting the passing wavelength of the optical filter based on the wavelength information detected by the spectrometer;

and controlling the foldable mirror to enable the optical filter and the first beam splitting sheet to be in optical path connection.

11. The method of claim 9, wherein, when the nanowire imaging device comprises a second imaging device, before the obtaining the overlay image obtained by the first imaging device in the current imaging round, further comprising:

obtaining an image of the sample obtained by the second imaging device;

determining a movement pattern based on the imaging of the sample;

and controlling the sample stage to move based on the moving mode.

12. A group refractive index measurement device implemented using the nanowire imaging device of any one of claims 1-8, comprising:

the information acquisition module is used for acquiring the position information of the sliding assembly under the current imaging round and determining the delay time of the current imaging round based on the position information;

an imaging acquisition module for acquiring overlapping images acquired by the first imaging device in the current imaging round;

the component control module is used for controlling the sliding component to move under the condition that the current imaging round is not the last imaging round so as to move the sliding component to the position of the next imaging round, and the next imaging round is taken as the current imaging round to obtain a plurality of overlapped images with different delay times;

an information determination module for determining interference fringe intensity distribution information based on the plurality of overlapping images of different delay times;

a group refractive index determination module for determining a group velocity based on the interference fringe intensity distribution information, the delay time of the overlay imaging of the plurality of different delay times, and the length of the nanowire sample, and determining a group refractive index of the nanowire sample based on the group velocity.

13. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the program implements a group refractive index measurement method according to any one of claims 9 to 11.

14. A non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program when executed by a processor implements the group refractive index measurement method according to any one of claims 9 to 11.

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