Optical constant measuring apparatus and method thereof

• US 8,970,831 B2
• Filed: 11/15/2012
• Issued: 03/03/2015
• Est. Priority Date: 11/29/2011
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Song, Hyun Woo
• Primary Examiner(s): Nur, Abdullahi
• Application Number:
  US13/678,453
• Publication Number:
  US 20130135611A1
• Time in Patent Office: 838 Days
• Field of Search: 356 72- 73
• US Class Current: 356/73
• CPC Class Codes: G01N 21/21 Polarisation-affecting properties G01N21/19 takes precedence
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B
• CPC Class Codes: G01N 21/55 Specular reflectivity

Abstract

Disclosed is an optical constant measuring method which includes applying light to a sample including a target material; measuring a first optical signal from light reflected from the sample; grasping a structure of the sample based on the first optical signal; measuring a second optical signal from light penetrating the sample; grasping an overall optical property of the sample based on the second optical signal; and measuring an optical constant of the target material based on the measured structure and optical property of the sample.

Claims

1. An optical constant measuring method comprising:

applying light to a sample including a target material;

measuring a first optical signal from light reflected from the sample;

grasping a structure of the sample based on the first optical signal;

measuring a second optical signal from light penetrating the sample;

grasping an optical property of the sample based on the second optical signal; and

measuring an optical constant of the target material based on the measured structure and optical property of the sample,

wherein grasping a structure of the sample based on the first optical signal comprises;

analyzing a cross sectional structure of the sample using the first optical signal; and

calculating a prime optical path of light penetrating the sample based on the analyzed cross sectional structure of the sample.

2. The optical constant measuring method of claim 1, wherein the light has a broad band-width in wavelength.

3. The optical constant measuring method of claim 1, wherein the first optical signal includes amplitude and spectrum of light reflected from the sample.

4. The optical constant measuring method of claim 1, wherein the second optical signal includes an angle of polarization rotation of light penetrating the sample.

5. The optical constant measuring method of claim 1, wherein calculating a prime optical path of light penetrating the sample comprises extracting a cross sectional boundary plane of the sample using the analyzed cross sectional structure of the sample.

6. An optical constant measuring apparatus comprising:

a first light source generating an incident light;

a second light source generating a linearly polarized light;

an optical splitter making amplitude distribution on an incident light applied from the first light source into a first split light and a second split light;

a reflection mirror reflecting the first split light again to the optical splitter;

a dichroic mirror passing the polarized light applied from the second light source and reflecting the second split light applied from the optical splitter;

a scanner applying the polarized light transmitting the dichroic mirror and the second split light reflected from the dichroic mirror to a sample;

a first optical analysis module measuring an optical signal based on the first split light, reflected from the reflection mirror to be again applied to the optical splitter, and the second split light reflected from the sample to be again applied to the optical splitter;

a second optical analysis module measuring an optical signal of the polarized light penetrating the sample; and

a result display unit analyzing information from the first and second optical analysis modules to display a result.

7. The optical constant measuring apparatus of claim 6, further comprising:

a first collimator collimating a light incident onto the reflection mirror from the optical splitter; and

a second collimator collimating a light incident onto the dichroic mirror from the optical splitter.

8. The optical constant measuring apparatus of claim 6, further comprising:

a polarization controller adjusting a polarization property of a light incident onto the reflection mirror from the optical splitter.

9. An optical constant measuring apparatus comprising:

a light source generating a light;

an optical splitter splitting the light from the light source into a first light and a second light through amplitude distribution;

a polarization adjusting unit varying a polarization property of a first light applied to the optical splitter;

a reflection mirror reflecting the first light applied through the polarization adjusting unit into the optical splitter;

a polarizer polarizing a second light applied from the optical splitter;

a scanner applying the polarized second light to a sample;

a first optical analysis module measuring an optical constant based on the first light, reflected from the reflection mirror to be again applied to the optical splitter, and the second light reflected from the sample to be again applied to the optical splitter;

a second optical analysis module measuring an optical signal of the second light penetrating the sample; and

a result display unit analyzing information from the first and second optical analysis modules to display a result.