A microscopic angle-resolved reflected light phase information characterization system and measurement method thereof

Abstract

The present invention discloses a microscopic angle-resolved reflected light phase information characterization system and a measurement method thereof. The device is divided into an optical path 1 and an optical path 2. Both optical paths have a microscopic function. The lenses in front of the two sample platforms are objective lenses, which can be used as Fourier transform devices to achieve the corresponding relationship between the angle of light emitted by the sample and the position on the focal plane of the objective lens; the rear-end 1 / 4 wave plate and the analyzer modulate the light, and finally converge the light to the image plane through the lens. The device can simultaneously measure the intensity and phase information of the reflected light under different incident angles in the sample micro-region, and can obtain comprehensive information of the reflected spectrum, providing a practical spectrum detection technology for artificial micro-nano structures such as metamaterials, optical antennas, and plasmon arrays, as well as optical films, natural materials and other systems.

Description

Technical Field

[0001] The invention relates to the technical field of material surface micro-area reflected light intensity and phase detection, and in particular to a development and testing method of an ultraviolet, visible-near infrared and other band spectral reflected light intensity and phase characterization system. Background Art

[0002] When an electromagnetic wave is incident on an interface composed of two different media, reflection usually occurs. Compared with the incident light, in many cases, the reflected light will not only have a change in amplitude but also a change in phase, and its behavior is ultimately determined by these two parts of information. In recent years, the emergence of artificial micro-nanostructure concepts such as metamaterials (metasurfaces), optical antennas, and plasmon arrays has greatly enriched people's means of manipulating electromagnetic waves. Taking metamaterials as an example, under external stimulation, the "artificial atoms" that make up the material - artificial sub-wavelength microstructure units - as sub-wave sources, can achieve arbitrary electromagnetic radiation intensity and phase distribution according to the design, thereby achieving arbitrary electromagnetic wavefront control. And with the continuous development of science and technology, people have higher and higher requirements for the miniaturization and integration of devices. In order to master the control performance of electromagnetic waves by complex micro-scale spatial structures, people have put forward new requirements for spectral detection technology: first, phase is an important physical quantity describing electromagnetic waves. In order to more accurately grasp the propagation behavior of electromagnetic waves, it is necessary to know its phase information; second, for miniaturized, integrated, and micro-scale devices, how to achieve accurate spectral information test characterization; finally, in order to master the control ability of devices under different angles of electromagnetic wave incidence conditions, angle-resolved spectral information is also required. However, the prior art is very mature in the measurement of spectral intensity information, but there are few methods for detecting phase information of variable-angle micro-regions, especially for electromagnetic waves in high-frequency bands such as infrared, visible light, and even ultraviolet light. The present invention discloses a microscopic angle-resolved reflected light phase information characterization device and a measurement method thereof. The front end of the measuring device splits light through a polarization beam splitter, which is used for sample detection and background reference respectively. The rear end 1 / 4 wave plate and the analyzer modulate the light to make the test light carrying sample information and the reference light coherently interfere, and the phase information is calculated by detecting the spectral intensity. The device can simultaneously measure the intensity and phase information of reflected light in a tiny area of ​​the sample under different incident angles, thereby obtaining comprehensive information of the reflected spectrum, providing a practical spectral detection technology for artificial micro-nano structures such as metamaterials, optical antennas, plasmon arrays, as well as material systems such as optical films and natural materials. Summary of the invention

[0003] The purpose of the present invention is to provide a spectral reflection intensity and phase test characterization system and its measurement method, which makes up for the deficiency that visible-near infrared phase information can only be simulated by simulation software, and realizes the synchronous measurement technology of visible-near infrared band spectral intensity and phase information.

[0004] The first purpose of the present invention is to simultaneously test the reflected light intensity information and phase information of the measured sample and obtain the comprehensive reflection spectrum information of the measured sample.

[0005] The second purpose of the present invention is to test the reflection spectrum intensity and phase information of the micro-nano region of a small sample of the sample being tested.

[0006] The third objective of the present invention is to test the intensity and phase information of the reflection spectrum at different incident angles.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] 1. A microscopic angular resolved reflected light phase information characterization device, comprising: a light source 1, a collimator 2, a polarizer 3, a polarization beam splitter 4, a first 1 / 4 wave plate 5, a first objective lens 6, a first sample stage 7, a first focal plane 8, a second 1 / 4 wave plate 9, a second objective lens 10, a second sample stage 11, a second focal plane 12, a third 1 / 4 wave plate 13, an analyzer 14, a lens 15, an image plane 16, a precision translation pinhole 17, an optical fiber 18, and a detector 19.

[0009] 2. The light from the light source 1 first passes through the collimator 2 and the polarizer 3, and then passes through the polarization beam splitter 4, and the light is divided into two light paths, light path 1 and light path 2; the light of light path 1 passes through the first 1 / 4 wave plate 5, and then passes through the first objective lens 6 to irradiate on the first sample stage 7. The focal plane of the first objective lens 6 is the first focal plane 8. The light with the same reflection angle on the sample to be measured converges at the same point of the first focal plane 8 through the first objective lens 6, and at the same time passes through the first 1 / 4 wave plate 5 and enters the first polarization beam splitter 4 again; the light of light path 2 passes through the second 1 / 4 wave plate 9, and then passes through the second objective lens 10 to irradiate on the second sample On the stage 11, the focal plane of the second objective lens 10 is the second focal plane 12. The light reflected at the same angle on the standard sample is converged at the same point of the second focal plane 12 through the second objective lens 10, and at the same time passes through the second 1 / 4 wave plate 9 and then enters the first polarization beam splitter 4 again. The two merged light beams are emitted at the same time and pass through the third 1 / 4 wave plate 13, the analyzer 14, and the lens 15 in sequence, and are imaged at the image plane 16. The position on the image plane 16 corresponds to the test angle one by one. The reflected light information at different incident angles is received by moving the precision translation pinhole 17, and finally is received by the detector 19 through the optical fiber 18.

[0010] 3. The splitting ratio of the polarization beam splitter 4 is 1:1.

[0011] 4. The light of the same angle emitted by the test sample on the first sample platform 7 converges at the same point on the first focal plane 8, and the light of different angles corresponds to the position on the first focal plane 8 one by one; the light of the same angle emitted by the reference sample on the second sample platform 11 converges at the same point on the second focal plane 12, and the light of different angles corresponds to the position on the second focal plane 12 one by one. Finally, the position on the image plane 16 corresponds to the test angle one by one, and the system realizes the test of reflected light information at different angles.

[0012] 5. The system tests sample micro-areas.

[0013] 6. The microscopic angle-resolved reflected light phase information characterization system and its measurement method according to claim 1, characterized in that it comprises the following steps:

[0014] Step 1: Fix the position of the precise translation pinhole 17;

[0015] Step 2: Background test: Put the standard samples on the first sample stage 7 and the second sample stage 11 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ;

[0016] Step 3: Test of one polarized reflected light of the sample under test: Place the sample under test on the first sample stage 7, and place the standard sample on the second sample stage 11. Test the four corresponding light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ;

[0017] Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization:

[0018] I0=I 10 -I 00 , I1=I 11 -I 01 , I2=I 12 -I 02 , I3=I 13 -I 03

[0019] Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for:

[0020]

[0021] Step 6: Change the position of the precision translation pinhole 17, and repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase.

[0022] Step 7: In step 3, place the standard sample on the first sample stage 7 and the sample to be measured on the second sample stage 11, and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The phase testing system of the present invention is not limited to the detection wavelength range.

[0025] 2. The present invention simultaneously measures the intensity and phase information of the reflected light in the microscopic area of ​​the sample being measured.

[0026] 3. The incident angle range of the present invention is large, and the minimum measurement angle is 0 degrees.

[0027] 4. The optical path of the present invention is simple.

[0028] 5. The phase calculation method of the present invention is simple.

[0029] 6. The device tests the reflection information under any polarized incident light conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a light path diagram of a microscopic angle-resolved reflected light phase information characterization device of the present invention;

[0031] Reference numerals:

[0032] 1-light source, 2-collimator, 3-polarizer, 4-polarization beam splitter, 5-first 1 / 4 wave plate, 6-first objective lens, 7-first sample stage, 8-first focal plane, 9-second 1 / 4 wave plate, 10-second objective lens, 11-second sample stage, 12-second focal plane, 13-third 1 / 4 wave plate, 14-analyzer, 15-lens, 16-image plane, 17-precision translation pinhole, 18-optical fiber, 19-detector. DETAILED DESCRIPTION

[0033] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0034] like Figure 1 As shown, the optical path of a microscopic angle-resolved reflected light phase information characterization system:

[0035] The light from the light source 1 first passes through the collimator 2 and the polarizer 3, and then passes through the polarization beam splitter 4, and the light is divided into two light paths, the light path 1 and the light path 2; the light of the light path 1 passes through the first 1 / 4 wave plate 5, and then passes through the first objective lens 6 to irradiate the first sample stage 7. The focal plane of the first objective lens 6 is the first focal plane 8. The light with the same reflection angle on the measured sample converges at the same point of the first focal plane 8 through the first objective lens 6, and at the same time enters the first polarization beam splitter 4 again after passing through the first 1 / 4 wave plate 5; the light of the light path 2 passes through the second 1 / 4 wave plate 9, and then passes through the second objective lens 10 to irradiate the second sample stage 11, the focal plane of the second objective lens 10 is the second focal plane 12, the light reflected at the same angle on the standard sample is converged at the same point of the second focal plane 12 through the second objective lens 10, and enters the first polarization beam splitter 4 again after passing through the second 1 / 4 wave plate 9, and the two beams of light after merging are emitted at the same time and pass through the third 1 / 4 wave plate 13, the analyzer 14, and the lens 15 in turn, and are imaged at the image plane 16. The position on the image plane 16 corresponds to the test angle one by one, and the reflected light information at different incident angles is received by moving the precision translation pinhole 17, and finally received by the detector 19 through the optical fiber 18. A microscopic angle-resolved reflected light phase information characterization system and its measurement method include the following steps:

[0036] Step 1: Fix the position of the precise translation pinhole 17;

[0037] Step 2: Background test: Put the standard samples on the first sample stage 7 and the second sample stage 11 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ;

[0038] Step 3: Test of one polarized reflected light of the sample under test: Place the sample under test on the first sample stage 7, and place the standard sample on the second sample stage 11. Test the four corresponding light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ;

[0039] Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization:

[0040] I0=I 10 -I 00 , I1=I 11 -I 01 , I2=I 12 -I 02 , I3=I 13 -I03

[0041] Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for:

[0042]

[0043] Step 6: Change the position of the precision translation pinhole 17, and repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase.

[0044] Step 7: In step 3, place the standard sample on the first sample stage 7 and the sample to be measured on the second sample stage 11, and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

[0045] Embodiment 1

[0046] A microscopic angle-resolved reflected light phase information characterization system and a measurement method thereof, constructed as follows Figure 1 The optical path shown in the figure, the method for measuring the intensity and phase information of the reflected spectrum is as follows:

[0047] Step 1: fix the position of the precise translation pinhole 17;

[0048] Step 2: Background test: Put the standard samples on the first sample stage 7 and the second sample stage 11 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ;

[0049] Step 3: Test of one polarized reflected light of the sample under test: Place the sample under test on the first sample stage 7, and place the standard sample on the second sample stage 11. Test the four corresponding light intensities when the azimuth angles of the polarizer 14 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ;

[0050] Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization:

[0051] I0=I 10 -I 00 , I1=I 11 -I 01 , I2=I 12 -I 02 , I3=I 13 -I 03

[0052] Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for:

[0053]

[0054] Step 6: Change the position of the precision translation pinhole 17, and repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase.

[0055] Step 7: In step 3, place the standard sample on the first sample stage 7 and the sample to be measured on the second sample stage 11, and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

[0056] In addition, it should be noted that the specific embodiments described in this specification may be named differently, and the above contents described in this specification are merely examples of the structure of the present invention. Any small or simple changes made based on the structure, features and principles of the present invention are included in the protection scope of the present invention. Those skilled in the art of the present invention may make various modifications or supplements to the specific examples described or adopt similar methods, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A method for measuring optical phase information of a microscopic angle-resolved reflected light phase information characterization system, the system comprising: A light source (1), a collimator (2), a polarizer (3), a polarization beam splitter (4), a first quarter wave plate (5), a first objective lens (6), a first sample stage (7), a first focal plane (8), a second quarter wave plate (9), a second objective lens (10), a second sample stage (11), a second focal plane (12), a third quarter wave plate (13), an analyzer (14), a lens (15), an image plane (16), a precision translation pinhole (17), an optical fiber (18), and a detector (19); characterized in that: Light from a light source (1) first passes through a collimator (2) and a polarizer (3), and then passes through a polarization beam splitter (4), whereby the light is split into two light paths, namely, a light path 1 and a light path 2. Light on light path 1 passes through a first quarter wave plate (5), and then passes through a first objective lens (6) to be irradiated onto a first sample stage (7). The focal plane of the first objective lens (6) is a first focal plane (8). Light with the same reflection angle on the sample being measured passes through the first objective lens (6) and converges at the same point on the first focal plane (8). At the same time, the light passes through the first quarter wave plate (5) and then enters the first polarization beam splitter (4) again. Light on light path 2 passes through a second quarter wave plate (9), and then passes through a second objective lens (10) to be irradiated onto the second sample stage. (11), the focal plane of the second objective lens (10) is the second focal plane (12), the light reflected at the same angle on the standard sample passes through the second objective lens (10) and converges at the same point on the second focal plane (12), and passes through the second 1 / 4 wave plate (9) and enters the first polarization beam splitter (4) again, the two beams of light after merging are emitted simultaneously and pass through the third 1 / 4 wave plate (13), the analyzer (14), and the lens (15) in sequence, and are imaged at the image plane (16), the position on the image plane (16) corresponds to the test angle one by one, and the reflected light information of different incident angles is received by moving the precision translation pinhole (17), and finally is received by the detector (19) through the optical fiber (18); The method comprises the following steps: Step 1: Fix the position of the precision translation pinhole (17); Step 2: Background test: standard samples are placed on the first sample stage (7) and the second sample stage (11) at the same time, and the four corresponding light intensities are tested when the azimuth angles of the polarizer (14) are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ; Step 3: A polarized reflected light test of the sample to be tested is performed. The sample to be tested is placed on the first sample stage (7), and the standard sample is still placed on the second sample stage (11). The four corresponding light intensities are tested when the azimuth angles of the polarizer (14) are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ; Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization: I0=I 10 -I 00 ,I1=I 11 -I 11 ,I2=I 12 -I 02 ,I3=I 13 -I 03 Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for: Step 6: Change the position of the precision translation pinhole (17), repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase; Step 7: In step 3, place the standard sample on the first sample stage (7), place the sample to be tested on the second sample stage (11), and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

2. The optical phase information measurement method of the microscopic angle-resolved reflected light phase information characterization system according to claim 1, characterized in that: The polarization beam splitter (4) has a splitting ratio of 1:1.

Images