Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle
Mercury bromide (Hg<sub>2</sub>Br<sub>2</sub>) has been used to develop acousto-optic tunable filters (AOTFs) because it has several advantages, including a high refractive index, a broad optical bandwidth, and a relatively high figure of merit. Therefore, the measurement of...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-04-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/23/9/4208 |
| _version_ | 1797601757453352960 |
|---|---|
| author | Oh-Tae Kwon Geonwoo Kim Hyungjin Bae Jaeyeol Ryu Sikwan Woo Byoung-Kwan Cho |
| author_facet | Oh-Tae Kwon Geonwoo Kim Hyungjin Bae Jaeyeol Ryu Sikwan Woo Byoung-Kwan Cho |
| author_sort | Oh-Tae Kwon |
| collection | DOAJ |
| description | Mercury bromide (Hg<sub>2</sub>Br<sub>2</sub>) has been used to develop acousto-optic tunable filters (AOTFs) because it has several advantages, including a high refractive index, a broad optical bandwidth, and a relatively high figure of merit. Therefore, the measurement of its birefringence is a highly important factor for ensuring AOTF quality. However, for single crystals, it is difficult (at the millimeter scale) to quantify the birefringence using an ellipsometer, as this equipment is only designed to conduct measurements on thin films. In this study, a simple birefringence measurement system for Hg<sub>2</sub>Br<sub>2</sub> was developed based on Brewster’s angle at the millimeter scale. The planar distributions of the Hg<sub>2</sub>Br<sub>2</sub> crystal along the (100), (010), and (001) planes were used in the experiments. The developed measurement system can measure the reflected light intensity of the Hg<sub>2</sub>Br<sub>2</sub> crystal depending on the incidence angles (rotations at 0.01125° steps) and can calculate the ordinary and extraordinary refractive indices and birefringence. The calculated birefringence of the Hg<sub>2</sub>Br<sub>2</sub> crystal was 0.8548; this value exhibits an error of 0.64% compared with a value of 0.86 reported in the literature. The developed measurement system demonstrates the ability to be used to evaluate the quality of birefringent single crystals. |
| first_indexed | 2024-03-11T04:08:12Z |
| format | Article |
| id | doaj.art-a7f9b19368184155b3f9a5b929bfb3d1 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-11T04:08:12Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-a7f9b19368184155b3f9a5b929bfb3d12023-11-17T23:41:12ZengMDPI AGSensors1424-82202023-04-01239420810.3390/s23094208Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s AngleOh-Tae Kwon0Geonwoo Kim1Hyungjin Bae2Jaeyeol Ryu3Sikwan Woo4Byoung-Kwan Cho5Department of Biosystem Machinery Engineering, College of Agricultural and Life Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of KoreaDepartment of Biosystem Bio-Industrial Machinery Engineering, College of Agricultural and Life Science, Gyeongsang National University, 501 Jinju-daero, Jinju 52828, Republic of KoreaDepartment of Biosystem Machinery Engineering, College of Agricultural and Life Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of KoreaDepartment of Space Optics R&D, Green Optics, 45, Ganri 1-gil, Cheongwon-gu, Cheongju 28126, Republic of KoreaDepartment of Space Optics R&D, Green Optics, 45, Ganri 1-gil, Cheongwon-gu, Cheongju 28126, Republic of KoreaDepartment of Biosystem Machinery Engineering, College of Agricultural and Life Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of KoreaMercury bromide (Hg<sub>2</sub>Br<sub>2</sub>) has been used to develop acousto-optic tunable filters (AOTFs) because it has several advantages, including a high refractive index, a broad optical bandwidth, and a relatively high figure of merit. Therefore, the measurement of its birefringence is a highly important factor for ensuring AOTF quality. However, for single crystals, it is difficult (at the millimeter scale) to quantify the birefringence using an ellipsometer, as this equipment is only designed to conduct measurements on thin films. In this study, a simple birefringence measurement system for Hg<sub>2</sub>Br<sub>2</sub> was developed based on Brewster’s angle at the millimeter scale. The planar distributions of the Hg<sub>2</sub>Br<sub>2</sub> crystal along the (100), (010), and (001) planes were used in the experiments. The developed measurement system can measure the reflected light intensity of the Hg<sub>2</sub>Br<sub>2</sub> crystal depending on the incidence angles (rotations at 0.01125° steps) and can calculate the ordinary and extraordinary refractive indices and birefringence. The calculated birefringence of the Hg<sub>2</sub>Br<sub>2</sub> crystal was 0.8548; this value exhibits an error of 0.64% compared with a value of 0.86 reported in the literature. The developed measurement system demonstrates the ability to be used to evaluate the quality of birefringent single crystals.https://www.mdpi.com/1424-8220/23/9/4208AOTFHg<sub>2</sub>Br<sub>2</sub> crystalbirefringence measurementBrewster’s angle |
| spellingShingle | Oh-Tae Kwon Geonwoo Kim Hyungjin Bae Jaeyeol Ryu Sikwan Woo Byoung-Kwan Cho Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle Sensors AOTF Hg<sub>2</sub>Br<sub>2</sub> crystal birefringence measurement Brewster’s angle |
| title | Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle |
| title_full | Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle |
| title_fullStr | Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle |
| title_full_unstemmed | Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle |
| title_short | Development of a Mercury Bromide Birefringence Measurement System Based on Brewster’s Angle |
| title_sort | development of a mercury bromide birefringence measurement system based on brewster s angle |
| topic | AOTF Hg<sub>2</sub>Br<sub>2</sub> crystal birefringence measurement Brewster’s angle |
| url | https://www.mdpi.com/1424-8220/23/9/4208 |
| work_keys_str_mv | AT ohtaekwon developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle AT geonwookim developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle AT hyungjinbae developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle AT jaeyeolryu developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle AT sikwanwoo developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle AT byoungkwancho developmentofamercurybromidebirefringencemeasurementsystembasedonbrewstersangle |