• 제목/요약/키워드: OPTICS

검색결과 5,417건 처리시간 0.028초

Laser Welding Quality Monitoring with an Optical Fiber System

  • Kim, Jin-Tae;Kim, Do-Hyoung;Chung, Chin-Man;Baik, Sung-Hoon;Park, Seung-Kyu;Kim, Min-Suk
    • Journal of the Optical Society of Korea
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    • 제7권3호
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    • pp.193-196
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    • 2003
  • We have developed a laser welding monitoring system to monitor laser welding process conditions such as sample feed rate, laser focal position, and laser power. A 2 ㎾ Nd:YAG CW laser beam has been applied to the welding of a stainless steel plate (SUS306) to investigate the welding monitoring. Theradiation signal from the weld pool was guided back through the focusing optics and the laser delivery fiber, and measured by a photo detector. By changing the focus of the laser beam along the z-direction, the penetration depth of the welding material has been measured. That shows the penetration depth depends on the frequency fluctuations of the plume signals which can be used in welding quality control.

Optical Parametric Chirped-pulse Amplification of Femtosecond Ti:sapphire Laser Pulses by Using a BBO Crystal

  • Cha, Yong-Ho;Lee, Ki-Tae;Nam, Seong-Mo;Yoo, Byoung-Duk;Rhee, Yong-Joo
    • Journal of the Optical Society of Korea
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    • 제7권3호
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    • pp.139-144
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    • 2003
  • We have characterized the optical parametric chirped-pulse amplification of femtosecond Ti:sapphire laser pulses by using a BBO crystal. It is numerically verified that a high gain and a broad gain bandwidth can be obtained with a 532-nm pump laser. The dependence of the gain profile of OPA on phase matching angles, pump intensity, and crystal length is numerically investigated. Experimental results shows that the temporal fluctuation of a pump laser causes the modulation of an amplified spectrum in OPCPA.

모형 안의 광학적 성능 (The optical properties on the human model eye)

  • 임현선;지택상;김봉환;김세진;윤성로
    • 한국안광학회지
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    • 제7권2호
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    • pp.203-207
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    • 2002
  • 본 연구에서는 NAVARRO, KOOIJMAN, MAHKICHOONG 모형안들을 이용하여 광학계의 성능을 유한광선 추적법으로 조사하였으며, 비정시안을 안경이나 콘택트렌즈로 교정할 때 참고자료로 활용 할 수 있고, 또한 눈의 굴절검사를 하는 기기인 자동안굴절력계, 각막굴절력계 등을 설계시 이러한 모형안들을 활용할 수 있다.

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