KR101282932B1 - Visibility Enhanced Low Coherence Interferometer - Google Patents
Visibility Enhanced Low Coherence Interferometer Download PDFInfo
- Publication number
- KR101282932B1 KR101282932B1 KR1020100104862A KR20100104862A KR101282932B1 KR 101282932 B1 KR101282932 B1 KR 101282932B1 KR 1020100104862 A KR1020100104862 A KR 1020100104862A KR 20100104862 A KR20100104862 A KR 20100104862A KR 101282932 B1 KR101282932 B1 KR 101282932B1
- Authority
- KR
- South Korea
- Prior art keywords
- light
- unit
- reflected
- measurement
- reference plane
- Prior art date
Links
Images
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Physics & Mathematics (AREA)
- Biomedical Technology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Instruments For Measurement Of Length By Optical Means (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Chemical & Material Sciences (AREA)
- Molecular Biology (AREA)
- Urology & Nephrology (AREA)
- Hematology (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Biophysics (AREA)
- Optics & Photonics (AREA)
Abstract
The present invention relates to a visibility-improved low coherence interferometer, and more specifically, to the injection locking method by using the white light (multi-wavelength) in the injection lock method to measure the amount of reflected light when measuring the step difference due to coherence of low reflectivity materials, such as in a fluid or semi-transparent biosample The present invention relates to a visibility enhancement low coherence interferometer that amplifies without phase distortion and improves visibility by equally or similarly reflecting a reference light signal and a reflected light signal reflected from a reference plane and a measurement plane, respectively.
Description
The present invention relates to a visibility-improved low coherence interferometer, and more specifically, to the injection locking method by using the white light (multi-wavelength) in the injection lock method to measure the amount of reflected light when measuring the step difference due to coherence of low reflectivity materials, such as in a fluid or semi-transparent biosample The present invention relates to a visibility enhancement low coherence interferometer that amplifies without phase distortion and improves visibility by equally or similarly reflecting a reference light signal and a reflected light signal reflected from a reference plane and a measurement plane, respectively.
Optical interferometers using a stabilized laser can be measured due to the speed of light retrospectively to the length standard. The measurement resolution can be obtained below nm, making it suitable for many applications requiring ultra-precision measurements.
Although the optical interferometer is one of the most accurate measurement techniques, it is difficult to measure a material with low reflectivity, which is commonly seen in real life by glass plates, color filters, specimens with rough surfaces, cells or molecules submerged in liquids, etc. .
For reliable measurement, the visibility of interference fringes should be good enough to analyze the received interference fringes. However, when measuring low reflectance materials, the intensity of light reflected from the measurement surface is very small, resulting in rapid visibility. Will fall out. This means that maximum visibility can be obtained when the intensity of light reflected from the reference plane and the measurement plane is the same, but low reflectance material has poor visibility due to the small reflected light.
To prevent this loss of visibility, amplify the intensity of light reflected from the measurement plane to match the intensity of light reflected from the reference plane, or adjust the intensity of light reflected from the reference plane to adjust the intensity of light reflected from the measurement plane. You can use a method to make it equal to the intensity, but there is a limited improvement in visibility.
The latter is a method of increasing the amount of reflected light by allowing more than 90% of the light to proceed to the measurement plane of the amount of light divided into the reference plane and the measurement plane. However, this method is not only troublesome to adjust the amount of light emitted from the measuring plane and the reference plane of the interferometer every time depending on the state of the measuring plane, but also the measurement itself may be impossible when the amount of light is less than the threshold of measurement. There are drawbacks to receiving.
The problem of poor visibility due to the difference in light quantity of the two split light beams has also been shown in low coherence interferometers using white light as the main light, which is used for the optical tomography of living organisms.
For example, low coherence interferometers are mainly used for optical tomography of living organisms by using white light (multi-wavelength) utilizing short interference distance due to wide frequency range as a main light source rather than short wavelength light source. The low coherence interferometer detects the vertices of the interference fringe obtained by precisely transferring the measurement plane or the reference plane in the optical axis direction so that three-dimensional shape measurement of the microsurface is performed.
However, as described above, most of the biosamples to be measured are semi-transparent materials, and thus the amount of reflected light is extremely small.
Therefore, it is necessary to study a device that can improve the accuracy of tomography by improving the visibility of semi-transparent materials while using white light.
The visibility improvement low coherence interferometer of the present invention,
When tomography is performed by varying the measurement plane or reference plane, even if the reflected light has a very small light quantity of nW level, the amplification is performed without changing the phase or time characteristics by the injection locking method using the secondary light source (auxiliary light source). The purpose of the present invention is to improve visibility by matching or making the amount of light reflected by the light reflected from the reference plane equal or similar.
Visibility improvement low coherence interferometer of the present invention for solving the above problems,
A main light source unit for irradiating multi-wavelength light; An optical splitter dividing the irradiated optical signal into two; A reference plane reflecting unit and a measuring plane reflecting unit for reflecting the optical signal separated by the light splitting unit to the reference plane and the measurement plane of the measurement object, respectively; A photodetector configured to combine the optical signals reflected by the reference plane reflector and the measurement plane reflector so that interference is observed and observe the interference; An optical axis fine moving unit for finely moving the reference plane or the measurement plane of the reference plane reflection unit in the optical axis direction; And an auxiliary light source unit for amplifying the reflected light through the injection lock.
The auxiliary light source unit is installed on either side of the reference plane reflection unit or the measurement plane reflection unit to amplify the reflected light signal reflected from the measurement plane reflection unit or the reference light signal reflected from the reference plane reflection unit,
Each of the reference plane reflector and the measurement plane reflector may be installed to amplify the weakly reflected light of the reflected light signal reflected from the measurement plane reflector and the reference light signal reflected from the reference plane reflector.
As described in detail above, the visibility enhancement low coherence interferometer of the present invention,
When measuring the level difference due to coherence of low reflectance materials such as semi-transparent biosample using white light (multi-wavelength), the amount of reflected light is amplified without phase distortion by injection locking method, and the reference light signal reflected from the reference plane and the measurement plane, respectively It is possible to provide a visibility enhancement low coherence interferometer with the same or similar reflected light signal.
1 is a block diagram showing a visibility enhancement low coherence interferometer according to an embodiment of the present invention.
2 to 3 is a block diagram showing a visibility enhancement low coherence interferometer according to another embodiment of the present invention.
Hereinafter, the present invention will be described in detail with the accompanying drawings.
1 is a block diagram showing a visibility-enhanced low coherence interferometer according to an embodiment of the present invention. As described, the visibility enhancement low coherence interferometer according to the present invention is separated by a main
The main
The light irradiated from the main
The reference
The reference light signal reflected by the
In this process, the
The optical axis micro-movement unit enables automatic movement by electronic control to drive the PZT, LM guide or fine adjustment screw in the direction of the optical axis by power means such as a micromotor or a motor, or manually rotates the fine adjustment screw by rotating the fine adjustment screw directly. Conventional methods may be applied, such as to allow movement.
In this operation, tomography (shape measurement) of the low-reflective material, which is a semi-transparent biosample, is because the amount of reflected light is weak, and the auxiliary
The auxiliary
As shown in FIG. 2, the auxiliary
The auxiliary
In addition, the auxiliary
For example, as shown in FIG. 1, two circulators, a
The interference is observed in the
In addition, the
The
10: Improved visibility Low coherence interferometer
20: main light source
30: light splitting part
40: reference plane reflecting unit
41: reference plane
50: measuring surface reflector
51: measuring surface
60: light detector
70: optical axis fine moving part
80: auxiliary light source
91: incident light signal progress line 92: reflected light signal progress line
93: first circulator 94: second circulator
Claims (3)
An optical splitter 30 dividing the irradiated optical signal into two;
A reference plane reflecting unit 40 and a measuring plane reflecting unit 50 for reflecting the optical signal separated by the light splitting unit to the reference plane and the measurement plane of the measurement object, respectively;
A light detection unit 60 for combining low-coherence interference by observing the optical signals reflected by the reference plane reflection unit and the measurement plane reflection unit, and observing this;
An optical axis fine moving unit 70 for finely moving the reference plane or the measurement plane of the reference plane reflection unit in the optical axis direction;
It is configured to include; a secondary light source unit 80 for amplifying the reflected light through the injection lock,
The auxiliary light source unit 80 is installed in the measurement surface reflector 50, the visibility enhancement low coherence interferometer, characterized in that for amplifying the reflected light signal reflected from the measurement surface reflector without phase distortion.
The auxiliary light source unit (80) is a visibility enhancement low coherence interferometer, characterized in that the feedback control is carried out so that the visibility obtained by the light detector is kept constant.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020100104862A KR101282932B1 (en) | 2010-10-26 | 2010-10-26 | Visibility Enhanced Low Coherence Interferometer |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020100104862A KR101282932B1 (en) | 2010-10-26 | 2010-10-26 | Visibility Enhanced Low Coherence Interferometer |
Publications (2)
Publication Number | Publication Date |
---|---|
KR20120043526A KR20120043526A (en) | 2012-05-04 |
KR101282932B1 true KR101282932B1 (en) | 2013-07-05 |
Family
ID=46263683
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
KR1020100104862A KR101282932B1 (en) | 2010-10-26 | 2010-10-26 | Visibility Enhanced Low Coherence Interferometer |
Country Status (1)
Country | Link |
---|---|
KR (1) | KR101282932B1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20190125162A (en) | 2018-04-27 | 2019-11-06 | 주식회사 인포웍스 | System for Frequency Modulated Continuous Wave LiDAR using Coherent method |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101417663B1 (en) * | 2013-07-12 | 2014-07-11 | 한양대학교 산학협력단 | Recognition probe of fingerprint based on low coherence interferometer and recognition apparatus of fingerprint having the same |
KR102412253B1 (en) * | 2018-11-30 | 2022-06-24 | 한국전자통신연구원 | Apparatus and Method of Microbiome Analysis |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005527280A (en) | 2002-04-18 | 2005-09-15 | ハーグ−シュトライト アーゲー | Measurement of optical properties |
JP2009524064A (en) | 2006-01-23 | 2009-06-25 | ザイゴ コーポレーション | Interferometer system for monitoring objects |
JP2010085148A (en) | 2008-09-30 | 2010-04-15 | Nec Corp | Minute displacement measuring device, minute displacement measuring method, and minute displacement measuring program |
KR20100073703A (en) * | 2008-12-23 | 2010-07-01 | 광주과학기술원 | Optical coherence tomography system and sample measurements method using the same |
-
2010
- 2010-10-26 KR KR1020100104862A patent/KR101282932B1/en active IP Right Grant
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005527280A (en) | 2002-04-18 | 2005-09-15 | ハーグ−シュトライト アーゲー | Measurement of optical properties |
JP2009524064A (en) | 2006-01-23 | 2009-06-25 | ザイゴ コーポレーション | Interferometer system for monitoring objects |
JP2010085148A (en) | 2008-09-30 | 2010-04-15 | Nec Corp | Minute displacement measuring device, minute displacement measuring method, and minute displacement measuring program |
KR20100073703A (en) * | 2008-12-23 | 2010-07-01 | 광주과학기술원 | Optical coherence tomography system and sample measurements method using the same |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20190125162A (en) | 2018-04-27 | 2019-11-06 | 주식회사 인포웍스 | System for Frequency Modulated Continuous Wave LiDAR using Coherent method |
Also Published As
Publication number | Publication date |
---|---|
KR20120043526A (en) | 2012-05-04 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7545510B2 (en) | Method of characterizing transparent thin-films using differential optical sectioning interference microscopy | |
US20070229853A1 (en) | Nanometer contact detection method and apparatus for precision machining | |
JP2001141652A (en) | Method and apparatus for simultaneous measurement of refractive index and thickness of object to be measured by light interference method | |
WO2013091584A1 (en) | Method and device for detecting defects in substrate | |
JP2006250826A (en) | Measuring element, processing device and measuring method, and measuring element of refractive index | |
KR102285818B1 (en) | Apparatus for monitoring three-dimensional shape of target object capable of auto focusing in real time | |
US7079256B2 (en) | Interferometric optical apparatus and method for measurements | |
KR101282932B1 (en) | Visibility Enhanced Low Coherence Interferometer | |
US4361402A (en) | Apparatus for determining the refractive-index profile of optical fibers | |
EP2718666A1 (en) | Coupled multi-wavelength confocal systems for distance measurements | |
CN111964580B (en) | Device and method for detecting position and angle of film based on optical lever | |
US20120316830A1 (en) | Coupled multi-wavelength confocal systems for distance measurements | |
KR100978397B1 (en) | System for analyzing plasma density | |
Youk et al. | A simple reflection-type two-dimensional refractive index profile measurement technique for optical waveguides | |
JP2015010922A (en) | Refractive index measurement method, refractive index measurement apparatus, and optical element manufacturing method | |
CN109443240A (en) | A kind of laser triangulation optical measurement instrument and method based on intermediary layer scattering | |
US20120314200A1 (en) | Coupled multi-wavelength confocal systems for distance measurements | |
Kotwal et al. | Passive micron-scale time-of-flight with sunlight interferometry | |
JP2005106706A (en) | Instrument and method for measuring refractive index and thickness | |
KR101267879B1 (en) | Visibility Enhanced Interferometer | |
CN110899988B (en) | Laser marking focusing control method | |
AU2020101631A4 (en) | A transmissive enhanced phase microscopy imaging measurement system based on piezoelectric ceramics | |
AU2020101629A4 (en) | A reflective-transmissive enhanced phase microscopy imaging measurement system based on an F-P interferometer | |
CN219657497U (en) | All-fiber three-dimensional tomographic scanning system | |
Park et al. | Time encoded chromatic confocal microscopy for wide field 3 D surface profiling |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A201 | Request for examination | ||
E902 | Notification of reason for refusal | ||
E902 | Notification of reason for refusal | ||
E701 | Decision to grant or registration of patent right | ||
GRNT | Written decision to grant | ||
FPAY | Annual fee payment |
Payment date: 20160630 Year of fee payment: 4 |
|
FPAY | Annual fee payment |
Payment date: 20170626 Year of fee payment: 5 |
|
FPAY | Annual fee payment |
Payment date: 20180625 Year of fee payment: 6 |