A microscopic angle-resolved transmitted light phase information characterization system and its measurement method

Abstract

The present invention relates to a microscopic angular resolution transmitted 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 the light is converged to the image plane through the lens. The device can simultaneously measure the intensity and phase information of the transmitted light under different incident angles in the sample micro-region, and can obtain comprehensive information of the transmission 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 present invention relates to the technical field of material micro-area transmission light intensity and phase detection, and in particular to a development and testing method of a transmission light intensity and phase characterization system in ultraviolet, visible-near infrared and other bands. Background Art

[0002] Phase is one of the basic physical quantities that describe electromagnetic waves. For the transmission of electromagnetic waves, when electromagnetic waves are incident on the interface composed of two different media, their phase generally does not change. However, when electromagnetic waves propagate in a medium with a certain thickness, the phase will accumulate as the optical path increases. At the same time, different incident angles will also have a significant effect on the phase. In recent years, metamaterials (metasurfaces) composed of subwavelength artificial microstructure units have attracted widespread attention. This material has unique properties that natural materials do not have, and has brought new physical phenomena and interesting applications. Therefore, people are increasingly studying small structures, short-wavelength metasurfaces and other fields. The requirements for miniaturization and integration of devices are getting higher and higher. In order to master the control performance of complex microscale spatial structures on electromagnetic waves, people have put forward new requirements for spectral detection technology: First, phase is an important physical quantity that describes 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 microscale 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, angle-resolved spectral information is also required. However, there are few detection methods for phase information in the prior art, especially for high-frequency electromagnetic waves such as infrared, visible light and even ultraviolet light with microscopic angle resolution. The present patent discloses a device for characterizing the phase information of microscopic angle-resolved transmitted light and a method for measuring the same. The front end of the device is split by a polarization beam splitter into two optical paths, optical path 1 and optical path 2. Both optical paths have microscopic functions. 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 the 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 so that the test light and the reference light carrying the sample information interfere with each other, and the phase information is calculated by detecting the spectral intensity. The device can simultaneously measure the intensity and phase information of the transmitted light of small samples at different angles, so as to obtain comprehensive information of the transmitted spectrum, and provide a practical spectral detection technology for artificial micro-nano structures such as metamaterials, optical antennas, and plasmon arrays, as well as optical films, natural materials and other material systems. Summary of the invention

[0003] The purpose of the present invention is to provide a spectral transmission 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 transmitted light intensity information and phase information of the tested sample and obtain the comprehensive transmission spectrum information of the tested sample.

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

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

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

[0008] 1. A microscopic angular-resolved transmitted light phase information characterization system device, comprising: a light source 1, a collimator 2, a polarizer 3, a first polarization beam splitter 4, a first reflector 5, a second reflector 6, a first condenser 7, a first sample stage 8, a first objective lens 9, a first focal plane 10, a second condenser 11, a second sample stage 12, a second objective lens 13, a second focal plane 14, a second polarization beam splitter 15, a 1 / 4 wave plate 16, an analyzer 17, a lens 18, an image plane 19, a precision translation pinhole 20, an optical fiber 21, and a detector 22.

[0009] 2. The light from the light source 1 first passes through the collimator 2 and then the polarizer 3, and then passes through the first polarization beam splitter 4 to transmit the P polarized light as the test light and the reflected S polarized light as the reference light. After the test light passes through the reflector twice, the first condenser 7 irradiates the light onto the first sample platform (the sample to be tested is placed on it) 8. The focal plane of the first objective lens 9 is the first focal plane 10. The light of the same angle emitted from the sample to be tested is converged at the same point on the first focal plane 10 through the first objective lens 9, and then passes through the second polarization beam splitter 15; another beam of reflected S polarized light passes through the second condenser 11 and irradiates on the second sample platform 8. The reference sample is placed on a sample platform (vertically placed on the reference sample) 12, and the focal plane of the second objective lens 13 is the second focal plane 14. The light emitted from the reference sample at the same angle is converged at the same point on the second focal plane 14 through the second objective lens 13, and then interferes with the test light through the second polarization beam splitter 15. The interference light beam passes through the quarter-wave plate 16 and the analyzer 17, and then the lens 18 converges the light beam on the image plane 19. The position on the image plane 19 corresponds to the test angle one by one. The reflected light information at different incident angles is received by moving the precision translation pinhole 20, and finally is received by the detector 22 through the optical fiber 21.

[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 8 converges at the same point on the first focal plane 10, and the light of different angles corresponds to the position on the first focal plane 10 one by one; the light of the same angle emitted by the reference sample on the second sample platform 12 converges at the same point on the second focal plane 14, and the light of different angles corresponds to the position on the second focal plane 14 one by one. Finally, the position on the image plane 19 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 transmitted light phase information characterization system and the measurement method thereof according to claim 1, characterized in that it comprises the following steps:

[0014] Step 1: Fix the position of the precise translation pinhole 20;

[0015] Step 2: Background test: Put the standard samples on the first sample stage 8 and the second sample stage 12 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 17 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 8, and place the standard sample on the second sample stage 12. Test the corresponding four light intensities when the azimuth angles of the polarizer 17 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] I 0 =I 10 -I 00 , I 1 =I 11 -I 01 , I 2 =I 12 -I 02 , I 3 =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 20, 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 8, place the sample to be tested on the second sample stage 12, 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 transmitted 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 transmission 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 transmitted light phase information characterization device of the present invention;

[0031] Reference numerals:

[0032] 1-light source, 2-collimator, 3-polarizer, 4-first polarization beam splitter, 5-first reflector, 6-second reflector, 7-first focusing mirror, 8-first sample stage, 9-first objective lens, 10-first focal plane, 11-second focusing mirror, 12-second sample stage, 13-second objective lens, 14-second focal plane, 15-second polarization beam splitter, 16-1 / 4 wave plate, 17-analyzer, 18-lens, 19-image plane, 20-precision translation pinhole, 21-optical fiber, 22-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 1As shown, the optical path of a microscopic angle-resolved transmitted light phase information characterization system:

[0035] The light from the light source 1 first passes through the collimator 2 and then the polarizer 3, and then passes through the first polarization beam splitter 4 to transmit P polarized light as the test light and reflect S polarized light as the reference light. After the test light passes through the reflector twice, the first condenser 7 irradiates the light onto the first sample platform (the sample to be tested is placed on it) 8. The focal plane of the first objective lens 9 is the first focal plane 10. The light at the same angle emitted from the sample to be tested is converged at the same point on the first focal plane 10 through the first objective lens 9, and then passes through the second polarization beam splitter 15; another beam of reflected S polarized light passes through the second condenser 11 and irradiates on the second sample platform 8. The reference sample is placed on a sample platform (vertically placed on the reference sample) 12. The focal plane of the second objective lens 13 is the second focal plane 14. The light emitted from the reference sample at the same angle is converged at the same point on the second focal plane 14 through the second objective lens 13, and then interferes with the test light through the second polarization beam splitter 15. The interference light beam passes through the quarter-wave plate 16 and the analyzer 17, and then the lens 18 converges the light beam on the image plane 19. The position on the image plane 19 corresponds to the test angle one by one. The reflected light information at different incident angles is received by moving the precision translation pinhole 20, and finally received by the detector 22 through the optical fiber 21.

[0036] A microscopic angle-resolved transmitted light phase information characterization system and a measurement method thereof include the following steps:

[0037] Step 1: Fix the position of the precise translation pinhole 20;

[0038] Step 2: Background test: Put the standard samples on the first sample stage 8 and the second sample stage 12 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 17 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ;

[0039] Step 3: Test of one polarized reflected light of the sample under test: Place the sample under test on the first sample stage 8, and place the standard sample on the second sample stage 12. Test the corresponding four light intensities when the azimuth angles of the polarizer 17 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ;

[0040] Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization:

[0041] I 0 =I 10 -I00 , I 1 =I 11 -I 01 , I 2 =I 12 -I 02 , I 3 =I 13 -I 03

[0042] Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for:

[0043]

[0044] Step 6: Change the position of the precision translation pinhole 20, and repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase.

[0045] Step 7: In step 3, place the standard sample on the first sample stage 8, place the sample to be tested on the second sample stage 12, and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

[0046] Embodiment 1

[0047] Microscopic angle-resolved transmitted light phase information characterization system and measurement method thereof, the test method comprises the following steps:

[0048] A microscopic angle-resolved transmitted 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 transmitted spectrum is as follows:

[0049] Step 1: Fix the position of the precise translation pinhole 20;

[0050] Step 2: Background test: Put the standard samples on the first sample stage 8 and the second sample stage 12 at the same time, and test the corresponding four light intensities when the azimuth angles of the polarizer 17 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 00 ,I 01 ,I 02 ,I 03 ;

[0051] Step 3: Test of one polarized reflected light of the sample under test: Place the sample under test on the first sample stage 8, and place the standard sample on the second sample stage 12. Test the corresponding four light intensities when the azimuth angles of the polarizer 17 are 0 degrees, 45 degrees, 90 degrees, and 135 degrees respectively: I 10 ,I 11 ,I 12 ,I 13 ;

[0052] Step 4: Calculate the spectral change I caused by the reflection of the sample at this angle α under the corresponding polarization:

[0053] I 0 =I 10 -I 00 , I 1 =I 11 -I 01 , I 2 =I 12 -I 02 , I 3 =I 13 -I 03

[0054] Step 5: Calculate the phase change caused by the reflection of the sample at this angle α for:

[0055]

[0056] Step 6: Change the position of the precision translation pinhole 20, and repeat steps 2 to 5 to test and calculate the β-degree reflected light intensity and phase.

[0057] Step 7: In step 3, place the standard sample on the first sample stage 8, place the sample to be tested on the second sample stage 12, and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

[0058] 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 microscopic angle-resolved transmitted light phase information characterization system, comprising: A light source (1), a collimator (2), a polarizer (3), a first polarization beam splitter (4), a first reflector (5), a second reflector (6), a first condenser (7), a first sample stage (8), a first objective lens (9), a first focal plane (10), a second condenser (11), a second sample stage (12), a second objective lens (13), a second focal plane (14), a second polarization beam splitter (15), a quarter wave plate (16), an analyzer (17), a lens (18), an image plane (19), a precision translation pinhole (20), an optical fiber (21), and a detector (22); 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, light path 1 and light path 2. Light from light path 1 passes through two reflection mirrors and is irradiated onto a first sample stage (8) by a first condenser (7). The focal plane of a first objective lens (9) is a first focal plane (10). Light with the same transmission angle on a sample to be measured passes through the first objective lens (9) and converges at the same point on the first focal plane (10), and then enters a second polarization beam splitter (15). Light from light path 2 passes through a second condenser (11) and is irradiated onto a second sample stage (12). The focal plane of the second objective lens (13) is the second focal plane (14). Light of the same transmission angle on the standard sample is converged at the same point of the second focal plane (14) through the second objective lens (13), and then enters the second polarization beam splitter (15). The two merged light beams are emitted simultaneously and sequentially pass through a quarter wave plate (16), an analyzer (17), and a lens (18) to form an image at an image plane (19). The position on the image plane (19) corresponds to the test angle one by one. The reflected light information of different incident angles is received by moving the precision translation pinhole (20), and finally is received by a detector (22) through an optical fiber (21).

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

1.

3. A method for measuring optical phase information based on a microscopic angle-resolved transmitted light phase information characterization system according to claim 1, characterized in that The following steps are involved: Step 1: Fixing the position of the precision translation pinhole (20); Step 2: Background test: standard samples are placed on the first sample stage (8) and the second sample stage (12) at the same time, and the four corresponding light intensities are tested when the azimuth angles of the polarizer (17) 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 (8), and the standard sample is still placed on the second sample stage (12). The four corresponding light intensities are tested when the azimuth angles of the polarizer (17) 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 01 ,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 (20), 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 (8), place the sample to be tested on the second sample stage (12), and repeat steps 3 to 6 to measure the spectral intensity and phase information of another polarized reflected light of the sample.

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