• Title, Summary, Keyword: Laser diode

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Application of Voltage-Controlled 12-Laser Diode Array in the Optical Fiber Communication (전압에 의하여 구동 가능한 12-Laser Diode Array의 광통신에의 응용)

  • Lee, Shang-Shin;Jhee, Yoon-Kyoo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.11
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    • pp.1-8
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    • 1990
  • We made a 12-Laser Diode Array consisting of 12 Graded Index Separate Confinement (GRINSCH) InGaAs/Inp Buried Heterostructure 4 Quantum Well Laser Diodes and examined the potential of controlling lasing operation of each laser diode by the voltage to its electroabsorption region. Using Si V-Groove with 12 V-grooves, a 12-Laser Diode Array, and 12 optical fibers, we investigated the various characteristics of each laser diode by changing the voltage to its electro-absorption region. Finally, we thought over the promising way of implementing optical local area communication between electric circuit boards or between subscribers and a central office using a 12-Laser Diode Array, Si V-groove, and optical fibers.

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A widely tunable sampled-grating distributed feedback laser diode integrated with sampled-grating distributed bragg reflector (추출격자 분포 브래그 반사기가 집적된 광대역 파장가변 추출격자 분포 궤환 레이저 다이오드)

  • 김수현;정영철
    • Korean Journal of Optics and Photonics
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    • v.15 no.4
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    • pp.369-374
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    • 2004
  • In this paper, we propose a new tunable laser diode structure. The laser diode consists of a sampled-grating distributed feedback laser diode monolithically integrated with a sampled-grating distributed-Brags-Reflector. For a specific design, the possibility of continuous/discrete wavelength tuning over 27nm is confirmed by a numerical analysis using a split-step time domain model. Because the laser diode can be directly coupled with optical fiber without the intervention of the passive section, the laser diode exhibits higher output power than the conventional laser diode.

A Study on the Immunohistology in Injury Cure of Rat by using InGaAlP Laser Diode (InGaAlP 레이저다이오드를 적용한 Rat의 착상 치유에서 면역조직화학적 연구)

  • Yu, Seong-Mi;Park, Yong-Pil;Cheon, Min-Woo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.5
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    • pp.431-435
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    • 2009
  • The apparatus has been fabricated using the laser diode and microprocessor unit. The apparatus used a InGaAlP laser diode for laser medical therapy and was designed for a pulse width modulation type to increase stimulation effects. To raise the stimulus effect of the human body, the optical irradiation frequency could be set up. The study has executed in-vivo experiment by employing our own developed laser diode irradiation system to investigate the effects of the InGaAlP laser diode irradiation on the wound healing as a preliminary study aimed at the application of InGaAlP laser diode to wound healing of human skin injury. The study cut out whole skin layers of Sprague-Dawley rat on the back part in 1 cm circle and observed developing effects after executing light irradiation for 9 days, and in result it is found that the light irradiation rat showed earlier wound healing than non-irradiation rat during the experimental period. In addition, there are some differences found regarding the healing process between laser diode irradiated rats and non-irradiated ones.

Combustion Diagnostics Method Using Diode Laser Absorption Spectroscopy (다이오드 레이저를 이용한 연소진단기법)

  • Cha, Hak-Joo;Kim, Min-Soo;Shin, Myung-Chul;Kim, Se-Won;Kim, Hyuck-Joo;Han, Jae-Won
    • 한국연소학회:학술대회논문집
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    • pp.75-83
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    • 2003
  • Diode laser absorption system is advantageous of their non-invasive nature, fast response time, high sensitivity and real-time measurement capability. Furthermore, recent advances in room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications are enabling combustion diagnostics system based on diode laser absorption spectroscopy. So, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor system are now appearing for a variety of applications. The objective of this research is to take advantage of distributed feed-back diode laser and develope new gas sensing system. It experimentally found out that the wavelength, power characteristics as a function of injection current and temperature. In addition to direct absorption and wavelength modulation spectroscopy have been demonstrated in these experiments and have a bright prospect to this diode laser system.

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A Study of Temperature Characteristic and Recording Quality Improvement of Blu-ray Laser Diode for Optical Media Recording (광학 디스크 기록을 위한 Blu-ray Laser Diode의 온도특성 및 기록품질 개선에 관한 연구)

  • Lee, Do-Han;Kim, Young-Kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • pp.503-505
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    • 2009
  • In this paper, we research the method for write quality improvement by temperature characteristic of Laser diode for optical recording. Differential Resistance of Blu-ray laser diode is changed by temperature. We analyze the effect of the change of the differential resistance and propose the method for the write quality improvement.

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Temperature Characteristic and Writing Quality Improvement of Blu-ray Laser Diode for Optical Disc Recording (광학 디스크 기록을 위한 Blu-ray Laser Diode의 온도특성 및 기록품질 개선)

  • Lee, Do-Han;Kim, Young-Kil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.7
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    • pp.1687-1692
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    • 2010
  • In this paper, we research the method for write quality improvement by temperature characteristic of Laser diode for optical recording. Differential Resistance of Blu-ray laser diode is changed by temperature. We analyze the effect of the change of the differential resistance in low temperature and propose the method for the write quality improvement.

Generation of Resonant Laser for Mg Atomic Beam Cooling by Laser Diode (Laser Diode에 의한 Mg 원자 선속의 냉각용 Laser 발생)

  • 김필수
    • Proceedings of the Optical Society of Korea Conference
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    • pp.50-55
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    • 1991
  • Mg 원자선속의 냉각에 쓰일 diode laser의 특성과 이용가능성을 연구하였다. Mg 원자의 3P2-3D3 천이의 공명선 383.8nm를 얻기 위하여 Mitsubishi사의 ML형 laser diode를 택하여 주입전류와 온도를 변화시키고, 회절격자를 써서 767.6nm의 laser 광을 얻은 후 LiIO3 결정에 의해 383.8nm인 제2조화파를 생성하였다. Ring cavity 내에서 기본파가 공명할 때 증강계수는 15이었다.

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Application of DFB Diode Laser Sensor to Reacting Flow (I) - Estimation and Application to Laminar Flames -

  • Park, Gyung-Min;Masashi Katsuki;Kim, Duck-Jool
    • Journal of Mechanical Science and Technology
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    • v.16 no.11
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    • pp.1550-1557
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    • 2002
  • Diode laser sensor for measuring gas temperature and species concentration in combustion chamber was developed using 2.0 tim distributed feed back lasers. To evaluate the measurement sensitivity of diode laser sensor system, CO2 survey spectra near 2.0 Um were measured and compared with the calculated one. This diode laser absorption sensor was applied to measure gas temperatures in a premixed flat flame of CH$_4$-air mixture. Experimental results were in good agreement with the values by an R-type thermocouple within 6.12%. In addition, successful demonstration of measurement of gas temperature and species concentration in a soot flame showed the promising possibility of diode laser absorption sensors for practical combustion system with non-intrusive method.

Healing Effect of 635 nm Laser Diode in Skin Injury (635nm 레이저다이오드의 피부 결손 치유 효과)

  • Cheon, Min-Woo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.7
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    • pp.674-678
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    • 2008
  • Low level laser therapy has various therapy effects. This paper performed the basic study for fabricating the low level laser therapy apparatus, and one of the goals of this paper was to make this apparatus used handily. The apparatus has been fabricated using the laser diode and microprocessor unit. The apparatus used a 635 nm laser diode for laser medical therapy and was designed for a pulse width modulation type to increase stimulation effects. In this study, the designed device was used to find out how 635 nm laser diode affected the skin injury of SD-Rat(Sprague-Dawley Rat). We divided the participants into two groups; irradiation group which was irradiated 10 minutes a day for 9 consecutive days, and none irradiation group. The results showed that the study group had lower incidence of inflammation and faster recovery, compared with the control group.

Species Concentration Measurement Using Diode Laser Absorption Spectroscopy (I) (다이오드 레이저를 이용한 광흡수 농도 계측 기법 (I))

  • Ahn, Jae-Hyun;Kim, Yong-Mo;Kim, Se-Won
    • Journal of the Korean Society of Combustion
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    • v.9 no.3
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    • pp.27-35
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    • 2004
  • Diode laser absorption sensors are advantageous because they may provide fast, sensitive, absolute, and selective measurements of species concentration. These systems are very attractive for practical applications owing to its compactness, resonable cost, robustness, and ease of use. In addition, diode lasers are fiber-optic compatible and thus enable simultaneous measurements of multiple species along a line-of-sight. Recent advances of room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications make it possible to be applied for combustion diagnostics based on diode laser absorption spectroscopy. Therefore, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor systems are now appearing for variety of applications. The objectives of this research are to develope a new gas sensing system and to verify feasibility of this system. Wavelength and power characteristics as a function of injection current and temperature are experimentally found out. Direct absorption spectroscopy has been demonstrated in these experiments and has a bright prospect to this diode laser system.

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