• Title/Summary/Keyword: diode laser

Search Result 1,017, Processing Time 0.042 seconds

Study on junction temperature characteristics of TO-CAN laser diode for optimized screening tests (접합 온도를 고려한 TO-CAN 레이저 다이오드의 Screening 조건 연구)

  • 이동수
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.16 no.6
    • /
    • pp.126-129
    • /
    • 2002
  • To extract exact screening conditions of TO-CAN laser diode, junction temperature during screening was investigated. Temperature increase due to thermal resistance was measured and compared with theoretical calculation. Injection current dependence of injection temperature was derived with good agreement with experimental data and used to obtain accurate screening conditions.

Bidirectional 1.25-Gbps WDM-PON with Broadcasting Function Using A Fabry-Perot Laser Diode and RSOA

  • Pham, Thang T.;Kim, Hyun-Seung;Won, Yong-Yuk;Han, Sang-Kook
    • Journal of the Optical Society of Korea
    • /
    • v.12 no.4
    • /
    • pp.359-363
    • /
    • 2008
  • A novel WDM-PON system delivering bidirectional 1.25-Gbps data and broadcasting data is proposed. A subcarrier signal modulates optical carriers of a Fabry-Perot-laser-diode based broadband light source to broadcast to all users. Reflective semiconductor optical amplifiers are used as modulators for the baseband data at both the optical line terminal and the remote optical network unit for a channel. Bit error rate and error vector magnitude were measured to demonstrate the proposed scheme.

The Development of 63nm Diode Laser System for Photodynamic Therapy of Cancer (광역학적 암치료를 위한 635nm 다이오드 레이저 시스템 개발)

  • 임현수
    • Journal of Biomedical Engineering Research
    • /
    • v.24 no.4
    • /
    • pp.319-328
    • /
    • 2003
  • The purpose of this paper is to develop a medical laser system using the semiconductor diode laser in order to photodynamic cancel therapy as a light source. The ideal light source for photodynamic therapy would be a homogeneous nondiverging light with variable spot size and specific wavelength with stability. After due consideration in this point, in this paper, we used a diode laser resonator of 635nm wavelength. The development laser system have a statistical laser out beam with accuracy control using the constant current control of method and clinic-friendly with compact. In order to protect the diode resonator from the over-current, the rush-current and electrical fault, we specially designed. The most importance therapeutic factor are the radiation mode for cancer therapy. So we developed the radiation mode of CW(Continuous Wave), long pulse, short pulse, and burst pulse and can adjust the exposure time from several milli-second to several minute. The experimental result shows that laser beam power was increased linear from 10mW to 300mW according to the increasing input current and the increasing exposure time. The developed new compact diode laser system have a stability of output power and specific wavelength with easy control and transportable for many applications of PDT.

The SEM and SPM Study on the Change of Machined Titanium Implant Surface following Various Laser Treatments (수종의 레이저로 임프란트 표면 처리 시 표면 형태의 변화에 대한 주사전자 및 주사탐침 현미경적 연구)

  • Kim, In-Kyung;Chung, Chin-Hyung;Lim, Sung-Bin
    • Journal of Periodontal and Implant Science
    • /
    • v.31 no.2
    • /
    • pp.451-463
    • /
    • 2001
  • Following the extensive use of implant, the incidence of peri-implantitis increases. Guided bone regeneration has been used for the optimal treatment of this disease. Because implant surface was contaminated with plaque and calculus, cleaning and detoxification were needed for the reosseointegration when guided bone regeneration was performed. Various mechanical and chemical methods have been used for cleaning and detoxification of implant surface, air-powder abrasive and oversaturated citrate were known to be most effective among these methods. However, these methods were incomplete because these could not thoroughly remove bacteria of implant surface, moreover deformed implant surface. Recent studies for detoxification of the implant surface using laser were going on, $CO_2$ laser and Soft Diode laser were known to be effective among these methods. The purpose of this study was to obtain clinical guide by application these laser to implant surface. 15 experimental machined pure titanium cylinder models were fabricated. The $CO_2$ laser treatment under dry, wet and hydrogen peroxide condition or the Soft Diode laser treatment under Toluidine blue O solution condition was performed on the each of models. Each groups were examined with SPM and SEM to know whether their surface was changed. The results were as follows : 1. Surface roughness and surface form weren't changed when $CO_2$ laser was usedunder dry condition(P>0.05). 2. Surface roughness and surface form weren't changed when $CO_2$ laser was used under wet condition(P>0.05). 3. Surface roughness and surface form weren't changed when $CO_2$ laser was used under hydrogen peroxide condition(P>0.05). 4. Surface roughness and surface form weren't changed when Soft Diode laser was used under toluidine blue O solution condition(P>0.05). From the result of this study, it may be concluded that the $CO_2$ laser having relatively safe pulse mode and the Soft Diode laser used with photosensitizer can be used safely to treat peri-implantitis.

  • PDF

In Vivo Enhanced Indocyanine Green-Photothermal Therapy for a Subconjunctival Tumor

  • Kim, Chang Zoo;Lee, Sang Joon;Hwang, Sang Seok;Chae, Yu-Gyeong;Kwon, Daa Young;Ko, Taek Yong;Kim, Jun Hyeong;Jung, Min Jung;Masanganise, Rangarirai;Oak, Chulho;Ahn, Yeh-Chan
    • Current Optics and Photonics
    • /
    • v.5 no.3
    • /
    • pp.311-321
    • /
    • 2021
  • Indocyanine green (ICG) is a dye approved for use in clinical diagnostics. ICG remains in the intravascular space following intravenous administration, due to its ability to rapidly bind to the plasma proteins, and its therapeutic potential has been studied in well-vascularized cutaneous tumors. Here we have evaluated the clinical response of a subconjunctival tumor to photothermal therapy (PTT) using an ICG-enhanced near-infrared diode laser and its adverse effects, in a rabbit. 22 male New Zealand white rabbits with subconjunctival tumors were enrolled (control group 6, laser-only group 8, laser-with-ICG group 8). Rabbits in the laser-with-ICG group received ICG (twice, 2 mg/kg each time, intravenously) directly followed by irradiation with a diode laser (λ = 810 nm). Rabbits in the laser-only group were irradiated with the diode laser. ICG angiography, ultrasonography, and pathologic examination were performed to evaluate PTT response at specific time points (0, 2, and 4 weeks after PTT). Two weeks after initial treatment, the eight rabbits treated by laser with ICG showed a 100% response rate. There was no clinical response in both laser-only and control groups. ICG-PTT is a potential and effective palliative therapeutic modality for subconjunctival tumors.