CN108593563A - Optical material test method and optic analytical instrument used - Google Patents

Abstract

The invention discloses a kind of optical material test method and optic analytical instrument used, the method for this method optical material test includes the following steps：Step S100：Outfield is loaded to the optical sample；Step S200：Optical sample described in laser irradiation obtains the optical information of the optical sample light-emitting surface；Step S300：Adjust the outfield, the optical information is analyzed by optical detecting method, obtain the optical crystal two-fold exit point and/or refractive index with the outfield variation, analyze it is described change obtain the corresponding optical sample in each outfield phase transformation or domain structure variation.Refractive index parameter and second nonlinear signal by measuring optical sample can be achieved to study phase transformation or the domain structure variation in optical material.Another aspect of the present invention additionally provides analytical instrument used in a kind of this method.

Description

Optical material testing methods and optical analysis instruments used

technical field

The invention relates to an optical material testing method and the used optical analysis instrument, belonging to the field of material performance testing.

Background technique

There are many types of optical materials and are widely used, such as optical glass, optical crystal, optical film and so on. With the progress of human society, the demand for various advanced optical materials is also increasing, such as ferroelectric optical materials, which show great application potential in the fields of optical information processing and advanced optical devices, whether for national defense or civilian use On the one hand, the market prospect is huge. The exploration of ferroelectric optical materials with excellent properties not only depends on the synthesis of new materials, but also requires the assistance of testing methods that can detect the properties of materials, so as to achieve effective analysis and evaluation of materials.

The existing research often involves the study of the phase transition of materials, and the application fields of materials are often determined by their phase transition characteristics. The phase transition of materials is an important index to evaluate the performance of materials. Since the change of the internal structure of the material may be accompanied by a phase change, for optical materials, the change of the internal structure will have a significant impact on the optical parameters of the material, such as the change from a centered structure to a centerless structure, from anisotropic to anisotropic. same-sex etc. Similarly, the distribution and orientation of the domain structure existing in some optical materials will also have a great impact on the optical properties of the optical material, and there is also a problem of order degree.

Contents of the invention

According to one aspect of the present invention, a method for testing optical materials with simple operation and high result accuracy is provided. This method provides a simple detection method for the research of optical materials.

The method for said optical material test comprises the following steps:

Step S100: applying an external field to the optical sample;

Step S200: irradiating the optical sample with laser light to obtain optical information on the light-emitting surface of the optical sample;

Step S300: Adjust the external field, analyze the optical information according to the optical detection method, obtain the change of the birefringence point and/or refractive index of the optical crystal with the external field, and analyze the change to obtain each of the external fields a corresponding phase transition or domain structure change of said optical sample;

The external field is a temperature field and/or an electric field.

Optionally, the optical information is birefringence, and the optical detection method is polarization optical detection.

Optionally, the optical information is birefringence and refractive index, and the optical detection method is refractive index detection.

Optionally, the optical information is scattering information, and the optical detection method is optical scattering.

Optionally, the optical detection method is a second-order nonlinear effect, and the optical information is phase change and microstructure.

Another aspect of the present invention provides an optical analysis instrument for the optical material, including: a laser light source, a sample platform and a main detector, the optical sample is arranged on the sample platform, the laser light source and the optical sample The optical path of the light incident surface of the optical sample is connected; the main detector is connected with the optical path of the light outgoing surface of the optical sample, and the sample platform includes a loading device, and the loading device loads at least one external field to the optical sample.

Preferably, the optical analysis instrument for optical materials further includes: a system optical path, the system optical path is set in the connecting optical path between the laser light source and the light incident surface of the optical sample, and the system optical path includes: a first polarizing optical device , an aperture and a collimator, the laser light source is connected to the optical path of the first polarizing optical device; the first polarizing optical device is connected to the optical path of the aperture; the optical diaphragm is connected to the optical path of the collimator ; The collimator is connected with the optical path of the light incident surface of the optical sample.

Preferably, the optical path of the system further includes: a half-transparent/half-reflective mirror and an auxiliary detector, the half-transparent/half-reflective mirror is connected to the optical path of the collimator; the incident and/or reflection enters the half-transparent/half-reflective mirror The laser light is connected to the optical path of the auxiliary detector; the laser light transmitted through the half-transparent/half-reflective mirror is connected to the optical path of the optical sample.

Preferably, the energy intensity of the laser light source is >0; the laser light source is at least one of ultraviolet laser, visible wavelength laser or near-infrared laser.

Preferably, the optical analysis instrument for the optical material is used in the above optical material testing method.

Preferably, the sample platform rotates around the central axis of the sample platform, and the rotation angle can be read in degrees.

Preferably, the external field is a temperature field and/or a voltage field.

Preferably, the loading device includes: a temperature field device and a power supply device, the temperature field device is arranged on the sample platform, and adjusts the temperature of the optical sample; the power supply device is arranged on the sample platform, and provides The optical sample is powered.

Preferably, the temperature field device is a resistance heating element, and the temperature field provided by the resistance heating element is from room temperature to 500°C; or the temperature field device is a semiconductor element, and the temperature field provided by the semiconductor element is -20 to 100°C ; or the temperature field device is liquid nitrogen, and the temperature field provided by the liquid nitrogen is -100° C. to room temperature.

Preferably, the electric field provided by the power supply device is 0-10000V.

Preferably, the optical analysis instrument for optical materials further includes: a main detector platform and a second polarizing optical device, and the second polarizing optical device is arranged on the optical path where the main detector is connected to the light-emitting surface of the optical sample; The second polarization optical device and the main detector are arranged on the main detector platform; the main detector platform rotates around the optical sample with the optical sample as the center.

The beneficial effects of the present invention include but are not limited to:

(1) The optical material testing method provided by the present invention is easy to operate and has high accuracy of results.

(2) In the optical analysis instrument for optical materials provided by the present invention, the optical material is made into a sample device, placed on a sample platform, an external field is applied, and a laser light source is used to irradiate the sample for measurement. Then the laser signal is collected by the optical detection instrument, and the phase transition or domain structure change in the optical material is mainly studied by measuring the refractive index parameter and the second-order nonlinear signal of the optical sample. By measuring the refractive index parameters and second-order nonlinear optical signals of optical materials, it can accurately reflect the changes in the internal structure of optical materials. Precisely measure the refractive index parameters and nonlinear signals of optical materials, and realize real-time observation and analysis of phase transition process or domain structure changes of optical materials.

(3) The optical analysis instrument for optical material provided by the present invention, by applying an adjustable external field on the optical material, irradiates the measurement sample with laser light, uses the optical detection instrument to collect the laser signal emitted by the optical material, and obtains the refraction of the optical sample. Ratio and second-order nonlinear signals, and use it to study phase transitions or domain structure changes in optical materials. For the study of optical materials, a simple detection instrument is provided.

Description of drawings

Fig. 1 is a schematic structural view of an optical analysis instrument for optical materials in a first preferred embodiment provided by the present invention;

Fig. 2 is a schematic structural view of an optical analysis instrument for optical materials in a second preferred embodiment provided by the present invention;

Fig. 3 is a schematic structural view of an optical analysis instrument for optical materials in a third preferred embodiment provided by the present invention.

List of parts and reference numbers:

Part Name reference sign Laser light source 10 first polarizing optics twenty one aperture twenty two collimator twenty three Half-transparent/half-reflecting mirror twenty four auxiliary detector 25 main detector track 31 sample platform 33 optical sample 40 main detector platform 51 second polarizing optics 52 main detector 53

Detailed ways

The present invention is described in detail below in conjunction with examples, but the present invention is not limited to these examples.

One aspect of the present invention provides a method for testing optical materials using the above-mentioned optical analysis instrument for optical materials, comprising the following steps:

Step S100: applying an external field to the optical sample;

Step S200: irradiating the optical sample with laser light to obtain optical information on the light-emitting surface of the optical sample;

Step S300: Adjust the external field, analyze the optical information according to the optical detection method, obtain the change of the birefringence point and/or refractive index of the optical crystal with the external field, and analyze the change to obtain each of the external fields a corresponding phase transition or domain structure change of said optical sample;

The external field is a temperature field and/or an electric field.

Through this operation method, it is convenient to study the phase transition and domain structure of optical samples that are invisible to the naked eye. By adjusting the change of the applied external field, the relationship between the external field and the internal structure change of the optical sample is obtained, which provides a basis for further research on optical samples. Adjusting the outer field here includes raising or lowering the outer field. Optical detection methods include, but are not limited to: polarized optical detection, optical scattering detection, refractive index measurement, second order nonlinear effect detection.

Optionally, the optical information is birefringence, and the optical detection method is polarization optical detection. As an optional optical detection method, when the polarized optical detection of the optical device is carried out according to this method, the detectable phase transition process includes birefringence.

Optionally, the optical information is birefringence and refractive index, and the optical detection method is refractive index detection. When this method is used to measure the refractive index, both birefringence and refractive index can detect corresponding changes.

Optionally, the optical information is scattering information, and the optical detection method is optical scattering. When this method is used to measure optical scattering, changes in the scattering phenomenon can be detected.

Optionally, the optical detection method is a second-order nonlinear effect, and the optical information is phase change and microstructure. When this method is used to measure second-order nonlinear effects, phase transitions and microstructural changes can be detected. The microstructure here refers to the microstructure of domains.

In a specific embodiment, the temperature and the electric field strength loaded on the optical sample 40 are changed, that is, the temperature and the electric field strength are used as a pair of variables, and the corresponding refractive index and second-order nonlinear signal are measured, so as to analyze the optical sample 40 . Since the optical sample 40 has a pair of parallel optical light-passing surfaces here, the refractive index of the optical sample 40 can be measured by using the M-Z interferometry or measuring the translation of the laser beam; Using gratings, second-order nonlinear signals are analyzed. Assuming that the optical material to be measured undergoes a phase transition at temperature T, during the phase transition, it changes from anisotropic (low temperature state) to isotropic (high temperature state), in the optical analysis instrument designed in the present invention, the laser light source 10 acts on The optical sample 40 that is initially in a low-temperature state can measure the birefringence phenomenon. As the temperature on the optical sample 40 increases to reach the temperature T, the birefringence phenomenon disappears; assuming that the optical material to be measured produces a phase change at the temperature T, the phase In the process of transformation, it changes from a centerless structure (low temperature state) to a centered structure (high temperature state). The material has a centerless structure and has a second-order nonlinear optical effect. For the optical signal, as the temperature on the optical sample 40 increases to reach the temperature T, the optical material transforms into a centered structure, and the second-order nonlinear optical signal disappears at this time. The research on the domain structure is also similar. For anisotropic optical materials, if the orientation of the domain structure is in a disordered state, then the birefringence phenomenon will disappear, and the second-order nonlinear signal has little correlation with the direction of the optical sample 40. Raise the temperature on the optical sample 40 and strengthen the electric field intensity. During this dynamic process, the birefringence gradually increases to a certain value, and the direction correlation between the second-order nonlinear optical signal and the optical sample 40 is also continuously strengthened, supplemented by optical quality analysis. , also enabling indirect observation of the domain structure growth of the optical sample 40 .

In a specific embodiment, taking heating and/or applying an electric field as an example, and analyzing according to the above method, the obtained optical information change process, and the corresponding phase change and phase change process of the optical sample are listed in Table 1.

Table 1 Analysis result table of optical material test method after heating up and/or applying electric field

It can be seen from Table 1 that the detection method provided by the present invention can be used to study the changes of the invisible structure inside the optical material. The research process is simple and convenient, and the results are accurate and reliable.

Referring to FIG. 1 , the optical analysis instrument for optical materials provided by the present invention includes: a laser light source 10 , a sample platform 33 and a main detector 53 . The optical sample 40 is arranged on the sample platform 33, the laser light source 10 is connected to the light path of the light incident surface of the optical sample 40; the main detector 53 is connected to the light path of the light exit surface of the optical sample 40, and the The sample platform 33 includes a loading device that loads the optical sample 40 with at least one external field.

Herein, loading an external field refers to an external field that can be loaded on the optical sample 40 . External fields include, but are not limited to, physical quantity fields such as electric fields, thermal fields, light fields, pressure fields, and magnetic fields. The loading device can be various commonly used devices for applying physical quantities, such as a temperature field device. The loading device can be installed at any position of the optical sample 40 , it only needs to be able to load the optical sample 40 . The optical analysis instrument for optical materials provided by the invention is especially suitable for detecting phase transition and domain structure changes of optical materials. The optical analysis instrument for optical materials emits laser light to the optical sample 40 to be inspected. After the laser light is incident on the optical sample 40 , parameters such as the refractive index of the optical sample 40 can be obtained through the main detector 53 on the one hand. At the same time, changes in various conditions, such as temperature, voltage, and current intensity, are applied to the optical sample 40 through the loading device provided on the sample platform 33 . Therefore, the refractive index parameters and second-order nonlinear signals of the optical sample 40 under different environmental parameter conditions are measured, and the phase transition or domain structure change of the optical material is studied by this. Polarizers, diaphragms, collimators and related optical devices can be arranged on the optical path connecting the laser light source 10 and the sample platform 33 according to the needs of optical analysis. The linear or non-linear signal can be laser light transmitted from the optical sample 40 or reflected from the optical sample 40 into the main detector 53 .

The analysis and test object of the optical analysis instrument for optical materials is the phase transition process or domain structure change of optical materials. The possible internal structure changes in the phase transition process of the optical material will change its physical properties. The relevant physical quantity changes are observed through the main detector 53, such as changing from an isotropic structure to an anisotropic structure, and the optical material will change from an optical homogeneity to an anisotropic structure. The bulk transition has birefringence characteristics, and the optical analysis instrument designed by the present invention can accurately measure the change of the optical refractive index during the phase transition, so as to accurately grasp the corresponding internal structure changes of the optical material under different external field parameters. For example, when the optical material changes from a centered structure to a centerless structure, the laser light source 10 irradiates the optical sample 40 , and the generated second-order nonlinear signal will change accordingly, and the second-order nonlinear signal can be captured by the main detector 53 . For the domain structure in optical materials, its refractive index information and second-order nonlinear signals are also closely related to the size and distribution orientation of domains, and changes in domains will also bring about changes in both. Therefore, the phase transition and domain change of optical materials can be studied by using optical analysis instruments for optical materials.

The main detector 53 used here is an optical detection instrument capable of collecting laser signals. The main detection instrument includes an optical image acquisition system, an optical energy meter or an oscilloscope, and any one or a combination of these instruments can be used to analyze and collect optical signals during the work process.

Referring to FIG. 2 , in order to meet the measurement requirements of the optical analysis instrument, before the laser light source 10 irradiates the optical sample 40 , the laser needs to be properly processed, such as using a collimator to shape the laser beam to control the beam quality of the laser. By setting the polarizer so that the laser beam produces a single polarization state laser. Preferably, the optical analysis instrument for optical materials further includes: a system optical path, which is arranged in the optical path connecting the laser light source 10 and the optical sample 40, and the system optical path includes: a first polarizing optical device 21, Diaphragm 22 and collimator 23, the laser light source 10 is connected with the optical path of the first polarized optical device 21; the first polarized optical device 21 is connected with the optical path of the diaphragm 22; the diaphragm 22 is connected with the optical path of the The optical path of the collimator 23 is connected; the optical path of the collimator 23 is connected with the light incident surface of the optical sample 40 . The first polarization optical device 21 can control the polarization direction of the laser light incident into the optical sample 40 . The aperture 22 is an adjustable circular aperture or a slit aperture to control the optical quality of the laser light incident on the optical sample 40 . The collimator 23 shapes the laser beam incident on the optical sample 40 to control the divergence angle of the laser beam.

In a specific embodiment, the optical path connected by the laser light source 10 and the optical sample 40 is used as the working main axis (1) of the optical analysis instrument designed by the present invention; the first polarization optical device connected to the optical path in sequence is arranged along the working main axis (1) 21. A diaphragm 22 and a collimator 23. The first polarizing optical device 21 can rotate around the main axis of work (1). The diaphragm 22 is an adjustable circular diaphragm or a slit diaphragm.

Referring to Fig. 3, preferably, the optical path of the system further includes: a semi-transparent/half-reflective mirror 24 and an auxiliary detector 25, the semi-transparent/half-reflective mirror 24 is connected to the optical path of the collimator 23; the incident and/or The laser light reflected into the half-transparent/half-reflective mirror 24 is connected with the optical path of the auxiliary detector 25 ; the laser light transmitted through the half-transparent/half-reflective mirror 24 is connected with the optical path of the optical sample 40 . The reflection here refers to the light generated by reflection on the light incident surface of the optical sample 40 .

The semi-transparent/half-reflecting mirror 24 can be rotated by 90°, and can sample the laser light before the incident optical sample 40 and the laser light reflected back by the optical sample 40, and reflect the reflected laser light of the obtained optical sample 40 and the laser signal of the incident laser light To the auxiliary detector 25 for analysis. Thus, the refractive index of the optical sample 40 can be accurately measured.

Referring to Fig. 3, in a specific embodiment, the optical path connected with laser light source 10 and optical sample 40 is used as the working main axis (1) of the optical analysis instrument provided by the present invention; A polarizing optical device 21 , an aperture 22 , a collimator 23 and a half-transparent/half-reflecting mirror 24 . The first polarization optics 21 are capable of self-rotation about the main axis of work (1). The diaphragm 22 is an adjustable circular diaphragm or a slit diaphragm. (12) is the central symmetry axis of the auxiliary detector 25, and the half-transparent/half-reflecting mirror 24 is arranged at the vertical intersection of (12) and (1). The auxiliary detector 25 is arranged on (12), and is connected with the half-transparent/half-reflecting mirror 24 in an optical path.

Preferably, the sample platform 33 rotates around the central axis of the sample platform 33, and the degree of the rotation angle can be read.

Preferably, the optical analysis instrument for optical materials can be used to realize the above-mentioned optical material testing method.

In the present invention, the sample platform 33 has the function of rotating 360° in the horizontal direction, and can also accurately read the rotation angle of the platform, which facilitates the accurate measurement of the refractive index of the optical sample 40 by using an optical analysis instrument for optical materials. The existing measurement methods for the refractive index of optical materials include geometric method and interferometry. According to different methods, they have different requirements for the measurement sample. For example, the minimum deflection angle method needs to process the optical material to be measured into a shape that meets certain requirements. Prisms, and the optical material to be measured in the interferometry can be a flat sheet or a wedge-shaped sample. No matter which measurement method is used, the measurement accuracy of the refractive index can be improved by obtaining the precise angle value of the measurement sample. Similar to this, the second-order nonlinear signal generated by the laser in the optical material is closely related to the angle, and the rotation and angle measurement functions of the sample platform 33 help to achieve accurate measurement of related parameters of the optical material.

Preferably, the energy intensity of the laser light source 10 is >0. More preferably, the energy intensity of the laser light source 10 is 0.5-10 ⁷ W/cm ^-2 . The specific energy intensity can be selected according to the test requirements. For example, in linear optical testing, lower laser energy density can be used; in second-order nonlinear optical testing, higher laser energy density can be used.

Using the laser light source 10 with this intensity can realize the precise analysis of the phase transition process and the domain structure change of the optical material in the way of optical analysis. Firstly, the monochromaticity and directivity of the laser light source 10 can ensure accurate measurement of small changes in the refractive index, and secondly, the energy characteristics of the laser are the guarantee for generating sufficient intensity second-order nonlinear signals in optical materials. Considering that the properties of optical materials are closely related to the wavelength of light, the preferred wavelength of the laser light source 10 is replaceable. In order to achieve accurate measurement of various optical materials.

Preferably, the laser light source 10 is at least one of ultraviolet laser, visible wavelength laser or near-infrared laser. According to needs, a single wavelength laser or multiple lasers with different wavelengths can be selected to irradiate the optical sample 40 simultaneously.

Preferably, the external field is a temperature field and/or a voltage field. Preferably, the loading device includes a temperature field device and a power supply device, the temperature field device is arranged on the sample platform 33, and adjusts the temperature of the optical sample 40; the power supply device is arranged on the sample platform 33 , and supply power to the optical sample 40 .

Thereby, the sample platform 33 can apply a temperature field and an electric field with adjustable intensity to the optical sample 40 . Temperature is one of the important factors leading to material phase transition and domain structure change, so the sample platform 33 provided by the present invention needs to effectively control the temperature of the measurement sample. At the same time, an electric field is introduced on the measurement sample as needed to meet the special requirements in the research.

Preferably, the temperature field device is a resistance heating element, and the temperature field provided by the resistance heating element is from room temperature to 500°C. This temperature field can act on the optical sample 40 .

Preferably, the temperature field device is a semiconductor element, and the temperature field provided by the semiconductor element is -20-100°C. Therefore, the temperature range of the optical sample 40 is adjusted to be -20-100°C.

Preferably, the temperature field device is liquid nitrogen, and the temperature field provided by the liquid nitrogen is from -100°C to room temperature. Cooling the optical sample 40 can adjust the temperature range of the optical sample 40 to be -100° C. to room temperature.

Preferably, the electric field provided by the power supply device is 0-10000V. The voltage range for adjusting the optical sample 40 is 0-10000V. The current generated by the power supply device here can be direct current or alternating current.

Preferably, the main detector 53 rotates around the optical sample 40 with the optical sample 40 as the center.

The main detection instrument rotates around the test sample to collect optical signals. According to the measurement requirements, different optical detection instruments can be selected to collect the intensity, wavelength, polarization characteristics, images, etc. of optical signals. Thus, optical parameters of the optical sample 40 at different angles can be acquired.

In order to meet the measurement requirements of the optical analysis instrument provided by the present invention, suitable optical components need to be arranged in front of the main detector 53 to meet the requirements of signal collection. Optical polarizers, diaphragms and related optical devices can be placed in front of the main detection instrument.

2 and 3, preferably, the optical analysis instrument for optical materials further includes: a main detector platform 51 and a second polarization optical device 52, the second polarization optical device 52 is arranged between the main detector 53 and The optical path where the light-emitting surface of the optical sample 40 is connected; the second polarization optical device 52 and the main detector 53 are arranged on the main detector platform 51; 40 is the center of a circle rotating around the optical sample 40 .

Preferably, the optical sample 40 is a wedge prism processed from optical materials, and the parameters of the prism meet the measurement requirements. It is placed in the center of the sample platform 33, and the minimum deflection angle method or the self-collimation method can be used. The refractive index of the sample is precisely measured, and the main detector 53 rotates around the sample platform 33 to detect the second-order nonlinear signal generated from the optical sample 40 at a suitable position.

As a specific implementation mode, a typical working form of the optical analysis instrument for optical material phase transition and domain structure research provided by the present invention is shown in Fig. 3, which can be roughly divided into: light source part a, system optical path part b, Sample platform part c, detector part d. It includes: a laser light source 10 , a first polarizing optical device 21 , an aperture 22 , a collimator 23 , a half-transparent/half-reflecting mirror 24 , an auxiliary detector 25 , a sample platform 33 and an optical sample 40 . In a specific embodiment, the second polarization optics 52 are polarization optics for optical signal analysis. 31 denotes the rotation locus of the main probe 53 . In a specific embodiment, the main detector platform 51 can rotate around the optical sample along the main detector track 31, (1) is the working axis of the optical analysis instrument designed in the present invention, (11) passes through the center of the sample platform 33 and is connected with The working axis (l) is the vertical axis, and (l2) is the central symmetry axis of the auxiliary detector 25.

The laser light source 10 selects the radiation wavelength of the laser according to the requirements of measurement and analysis, and makes the laser pass through the center of rotation of the sample platform 33, and the optical path connected by the laser light source 10 and the optical sample 40 is used as the working axis of the optical analysis instrument provided by the present invention ( l); along the main axis of work (1) the first polarizing optics 21, aperture 22, collimator 23 and half-transparent/half-reflecting mirror 24 are set, the first polarizing optics 21 can rotate around the main axis of work (1) to control The polarization direction of the incident optical sample 40 laser light, the diaphragm 22 is an adjustable circular diaphragm or slit diaphragm to control the optical quality of the incident optical sample 40 laser light, and the collimator 23 shapes the incident optical sample 40 laser light To control the divergence angle of the laser light, the semi-transparent/half-reflective mirror 24 can be rotated 90° to sample the laser light before the incident optical sample 40 and the laser light reflected back by the optical sample 40, and reflect the laser signal to the auxiliary detector 25 for further processing. analyze. The optical sample 40 is processed from optical materials, and is an optical flat plate with a pair of parallel light-transmitting surfaces. It is placed on the rotation center of the sample platform 33, and an electric field with an adjustable voltage within a certain range is applied to the optical sample 40. The direction is vertical or parallel to the main axis of work (1), and different accessories are selected to control the temperature field of the optical sample 40 according to the requirements of measurement and analysis.

The optical detector platform 51 rotates around the rotation center of the sample platform 33 along the main detector track 31. The main detector 53 and related optical components are placed on the platform. The main detector 53 is used to receive the laser light source 10 and act on the optical sample. The linear and nonlinear signals after 40, the signal can be transmitted from the optical sample 40, or reflected by the optical sample 40, the second polarization optical device 52 is the most commonly used optical component before the main detector 53, used to assist the main detector 53 analyzes the polarization characteristics of the laser signal. According to application requirements, optical components commonly used in front of the main detector 53 include optical filters, attenuators, and apertures.

In order to describe the optical material testing method and the optical analysis instrument used in the present application more clearly, the optical material testing method and the optical analysis instrument used in the present application will be further described in different embodiments below.

Unless otherwise specified, the raw materials in the examples of the present invention were purchased through commercial channels.

Example 1 Using the above-mentioned optical material to test and measure the refractive index and birefringence related structural changes of the sample with an optical analysis instrument

According to a specific embodiment of the present invention, as shown in FIG. 3 , the phase transition process of barium titanate ferroelectric crystal is studied. The barium titanate ferroelectric crystal is processed into an optical sample 40 with a pair of parallel optical transparent surfaces, the thickness of the sample is 2-10 mm, it is placed on the rotation center of the sample platform 33, and the optical sample 40 is heated by replacing the temperature field attachment. Provide a temperature adjustment range of -100 ~ 200 ℃. The laser light source 10 uses a 632.8nm helium-neon laser, and the rotatable first polarization optical device 21 controls the polarization direction of the laser to be 45°, directly irradiating the optical sample 40; the main detector 53 uses a CCD linear array detector, fixed on the working spindle ( l) direction, a collimating magnifying glass group is placed in front of the detector. The refractive index of the optical sample 40 is calculated by measuring the translation of the laser beam relative to the working axis (l) and combining the angle between the normal of the optical surface of the optical sample 40 and the working axis (l). When the temperature of the optical sample 40 rises from -100°C to 120°C, birefringence can be observed. At -80°C and 0°C, the birefringence point changes significantly. At 120°C, the birefringence These three temperature points correspond to the phase transition points of trigonal crystal system→orthorhombic system, orthorhombic system→tetragonal system, tetragonal system→cubic system.

Example 2 Using the above-mentioned optical material to test and measure the refractive index and birefringence related structural changes of the sample with an optical analysis instrument

According to a specific embodiment of the present invention, as shown in FIG. 3 , the phase transition process of barium titanate ferroelectric crystal is studied. The barium titanate ferroelectric crystal is processed into an optical sample 40 in the shape of a right-angle prism, wherein the right-angle surface of the prism is a tangential direction, and it is placed on the rotation center of the sample platform 33, and a suitable temperature field accessory is selected to provide the optical sample 40 from room temperature to 200°C temperature adjustment range. The laser light source 10 uses high optical quality combined beam lasers. The laser wavelengths include 473nm, 532nm, 632.8nm and 1064nm. The laser light passes through the first polarizing optical device 21, the diaphragm 22, the collimator 23, and the half-transparent/half-reflecting mirror in turn. After 24, the optical sample 40 is irradiated; the auxiliary detector 25 uses a high-sensitivity photoelectric energy meter, and the photoelectric energy meter is equipped with an aperture to precisely control the optical path of the incident light. Using the self-collimation method, the auxiliary detector 25 accurately measures the vertex angle of the prism and the reflection angle of the refracted light beam, so that the refractive index of the optical sample 40 can be accurately measured. The temperature of the optical sample 40 rises from room temperature to 200°C, and the temperature of the optical sample 40 starts to rise from room temperature. Before reaching 120°C, birefringence can be observed, and the refractive index corresponding to different polarization states at each wavelength can be accurately measured. The refractive index changes slightly with temperature; when the temperature of the optical sample 40 exceeds 120°C, that is, the internal structure of the crystal changes from a tetragonal crystal system to a cubic crystal system, the birefringence disappears and the refractive index changes.

Example 3 Using the above-mentioned optical material to test and measure the refractive index and birefringence related structural changes of the sample with an optical analysis instrument

According to a specific embodiment of the present invention, as shown in FIG. 3 , the phase transition process of lead titanate ferroelectric crystal is studied. The lead titanate ferroelectric crystal is processed into an optical sample 40 in the shape of a right-angle prism, wherein the right-angle surface of the prism is a tangential direction, and it is placed on the rotation center of the sample platform 33, and an appropriate temperature field accessory is selected to provide the optical sample 40 with room temperature to The temperature adjustment range is 500°C, and an adjustable DC electric field is applied on the optical sample 40, the electric field voltage is from 0 to 10000V, and the electric field direction is perpendicular to the working axis (l). The laser light source 10 uses a 1064nm electro-optic modulated pulsed laser with high beam quality, and the laser light sequentially passes through the first polarizing optical device 21, the diaphragm 22, and the half-transparent/half-reflecting mirror 24 to irradiate the optical sample 40; the main detector 53 uses silicon photoelectric energy A cut-off filter is placed in front of the silicon photoelectric energy meter, which can completely filter out the 1064nm optical signal. The auxiliary detector 25 uses a high-sensitivity photoelectric energy meter. The photoelectric energy meter is equipped with a diaphragm to precisely control the optical path of the incident light. Using the self-collimation method, the auxiliary detector 25 accurately measures the vertex angle of the prism and the reflection angle of the refracted light beam, so that the refractive index of the optical sample 40 can be accurately measured. Under the conditions of room temperature and arbitrary electric field strength, the optical sample 40 cannot show birefringence and has obvious scattering due to the arbitrary orientation of the domain structure existing inside; when the electric field strength applied to the measured sample reaches a certain value, the electric field It begins to show its effect, and the birefringence phenomenon can be observed, and the birefringence index gradually increases with the increase of the electric field intensity. After the birefringence index reaches a certain value, it will not change. At the same time, the scattering phenomenon inside the crystal is also weaker than the initial one. While measuring the refractive index, the main detector 53 is used to collect the second-order nonlinear signal. At room temperature, the second-order nonlinear signal has little connection with the crystal directionality. As the temperature on the optical sample 40 increases and the applied electric field Strengthening, the correlation between the second-order nonlinear signal and the directionality of the crystal slowly increases. When the temperature and electric field exceed a certain range, the second-order nonlinear signal generated by the laser along most directions of the crystal is weaker than that at room temperature. Only in a specific direction, the second-order nonlinear signal The order nonlinear signal is obviously strengthened. The temperature on the optical sample 40 can be controlled by adding a heating device to the optical sample 40 .

The above are only a few embodiments of the present invention, and do not limit the present invention in any form. Although the present invention is disclosed above with preferred embodiments, it is not intended to limit the present invention. Any skilled person familiar with this field, Without departing from the scope of the technical solution of the present invention, some changes or modifications made using the technical content disclosed above are equivalent to equivalent implementation cases, and all belong to the scope of the technical solution.

Claims (10)

1. A method for optical material testing, is characterized in that, comprises the following steps: Step S100: applying an external field to the optical sample; Step S200: irradiating the optical sample with laser light to obtain optical information on the light-emitting surface of the optical sample; Step S300: Adjust the external field, analyze the optical information according to the optical detection method, obtain the change of the birefringence point and/or refractive index of the optical crystal with the external field, and analyze the change to obtain each of the external fields a corresponding phase transition or domain structure change of said optical sample; The external field is a temperature field and/or an electric field. 2. The method for testing optical materials according to claim 1, wherein the optical information is birefringence, and the optical detection method is polarization optical detection. 3. The method for testing optical materials according to claim 1, wherein the optical information is birefringence and refractive index, and the optical detection method is refractive index detection. 4. The method for testing optical materials according to claim 1, wherein the optical information is scattering information, and the optical detection method is optical scattering. 5. The method for testing optical materials according to claim 1, wherein the optical detection method is a second-order nonlinear effect, and the optical information is phase change and microstructure. 6. An optical analysis instrument for optical materials, comprising: a laser light source, a sample platform and a main detector, the optical sample is arranged on the sample platform, the light incident surface of the laser light source and the optical sample Optical connection; The main detector is connected to the optical path of the light exit surface of the optical sample, and the sample platform includes a loading device, and the loading device loads at least one external field to the optical sample. 7. The optical analysis instrument for optical materials according to claim 6, characterized in that, the optical analysis instrument for optical materials further comprises: a system optical path, the system optical path is arranged between the laser light source and the optical sample In the connecting optical path of the light incident surface, the optical path of the system includes: a first polarizing optical device, a diaphragm and a collimator, and the laser light source is connected to the optical path of the first polarizing optical device; The first polarizing optical device is connected to the optical path of the aperture; the aperture is connected to the optical path of the collimator; and the collimator is connected to the optical path of the light incident surface of the optical sample. 8. The optical analysis instrument for optical materials according to claim 7, wherein the optical path of the system further comprises: a semi-transparent/half-reflecting mirror and an auxiliary detector, the semi-transparent/half-reflecting mirror is parallel to the Light pipe light path connection; The laser light incident and/or reflected into the semi-transparent/half-reflecting mirror is connected to the optical path of the auxiliary detector; the laser light transmitted through the semi-transparent/half-reflecting mirror is connected to the optical path of the optical sample. 9. The optical analysis instrument for optical materials according to claim 6, wherein the energy intensity of the laser light source is >0; The laser light source is at least one of ultraviolet laser, visible wavelength laser or near-infrared laser. 10 . The optical analysis instrument for optical materials according to claim 6 , wherein the optical analysis instrument for optical materials is used for the optical material testing method according to any one of claims 1 to 5 . 11 .