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Development of Tilt angle measurement system of plastic thin-film using Position Sensitive Device

PSD를 이용한 플라스틱 박막 필름의 경사 각도 측정 시스템 개발

  • Kim, Gi-Seung (Division of Information Communication, Sunmoon University) ;
  • Park, Yoon-Chang (Division of Information Communication, Sunmoon University)
  • 김기승 (선문대학교 정보통신학과) ;
  • 박윤창 (선문대학교 정보통신학과)
  • Received : 2021.01.05
  • Accepted : 2021.02.05
  • Published : 2021.02.28

Abstract

Various types of precision plastic thin films are used widely in high-performance displays, such as smartphones. For plastic thin-films manufactured by the Roll-to-Roll process, the film thickness must be measured and managed while moving. In the Roll-to-Roll process, wrinkles are generated when tension is applied to the film, which causes an inclination on the optical axis of the thickness gauge, resulting in a loss of accuracy. Therefore, this study attempted to develop an optical interference tomography measurement system. In this study, the tilt angle of the film was measured to correct the measurement value error in the thickness gauge caused by the tilt of the film. The system was constructed so that the laser was irradiated on the tilted film, and the laser reflected from the film was formed on the PSD. The relationship between the tilt angle of the film and the output value of the PSD was obtained experimentally. Using this, a device to measure the tilt angle of the film was constructed, and angle measurements were taken at a speed of 250,000Hz.

스마트폰 등에서 사용되는 고성능 디스플레이에는 다양한 종류의 정밀한 플라스틱 박막 필름(Plastic Thin Film)이 사용되고 있다. 롤투롤(Roll-To-Roll) 공정으로 제조되는 플라스틱 박막 필름은 생산 공정 중에 실시간으로 필름의 두께가 계측되고, 정확하게 관리되어야 한다. 필름 제조 과정에서 필름에 장력이 작용하면서 주름이 발생되고, 이러한 주름 발생은 필름의 두께 방향과 두께 측정기의 광축이 서로 경사지게 한다. 결국 두께 측정기는 필름의 수직 두께가 아닌 경사진 두께를 측정하게 됨으로써 실제 두께보다 더 큰 값으로 측정하게 된다. 본 연구에서는, 플라스틱 필름의 경사로 인하여 발생하게 되는 두께 측정기에서의 계측값 오차를 보정하기 위하여, 필름의 경사 각도를 계측하는 연구가 진행되었다. 플라스틱 필름에 슬릿 빔 레이저를 조사하고, 필름에서 반사되는 슬릿 빔 레이저가 PSD(Position Sensitive Device)에 맺히는 광학 시스템을 구성하였으며, 실험을 통하여 필름의 경사 각도와 PSD 출력값의 관계를 1차 방정식 형태로 구하였다. 이를 이용하여 필름의 경사 각도를 측정하는 장치가 구축되었으며, 250KHz의 속도로 경사 각도의 측정이 가능하였다.

Keywords

References

  1. Jeon Hong Kang, Kwang Min Yu, Han Jun Kim, Sang Ok Han, "A Development of Thickness Meter for Conductive Thin Film", The Korean Institute of Electrical Engineers Summer Conference Proceedings, The Korean Institute of Electrical Engineers, Korea, pp.2057-2058, Jul. 2009.
  2. Sung-Soo Kim, Do-Yun Kim, "Development and Characteristics of the x-ray transmission anode tube for the thickness measurement of film", Applied Science and Convergence Technology, Vol.17, No.3, pp.240-246, May 2008. DOI: https://doi.org/10.5757/JKVS.2008.17.3.240
  3. Hyun-Ju Cho, Jun-Yeon Won, Yong-Gyu Jeong, Bong-Ju Woo, Jun-Ho Yoon, Chang-Kwon Hwangbo, "Determining the Thickness of a Trilayer Thin-Film Structure by Fourier-Transform Analysis", Korean Jurnal of Optics and Photonics, Vol.27, No.4, pp.143-150, Aug. 2016. DOI: http://dx.doi.org/10.3807/KJOP.2016.27.4.143
  4. Eun Jung, Sung-Jin Kim, Sung Min Cho, "Production Technology Status of Organic Lighting & Display via Roll-to-Roll Process", Vacuum Magazine, Vol.4, No.2, pp.24-28, Jun. 2017. DOI: https://doi.org/10.5757/vacmac.4.2.24
  5. Sudheer Koganti, Tushar Kotecha, Roby Rakhit, "Choice Of Intracoronary Imaging: When To Use Intravascular Ultrasound Or Optical Coherence Tomography", Interventional Cardiology, Vol.11, No.1, pp.11-16, May 2016. DOI: http://dx.doi.org/10.15420/icr.2016:6:1
  6. HAMAMATSU PHOTONICS K.K., One-dimensional PSD S3932 Data sheet [Internet]. Hamamatsu Photonics K.K., c2020 [cited 2020 July], Available From : https://www.hamamatsu.com/resources/pdf/ssd/s3931_etc_kpsd1002e.pdf (accessed Dec. 2, 2020)
  7. Sung Hyun. Park, Design of experiments. pp.259-274, minyoungsa, 1985.
  8. NATIONAL INSTRUMENTS, NI USB-6211 Data sheet [Internet]. National Instruments, c2017 [cited 2017 sep.], Available From : https://www.ni.com/pdf/manuals/375195d.pdf (accessed Dec. 2, 2020)