DOWNLOAD PDF 1997 CONFERENCE ON LASERS AND ELECTRO-OPTICS/PACIFIC RIM, CLEO/PACIFIC RIM

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1 Chapter 1 : Engr. Cleo Meet The Future CLEO-PR is the preeminent Pacific Rim forum reporting on the latest research and development in a wide range of laser and electro-optic disciplines, including fundamental physics of lasers and quantum optics, device development, systems engineering, and applications. In this report, we veri- fied properties of a reflectometer with a multidigitized coherent light source on the theoretical and experimental points of view. Then its usefulness is recognized by measuring a multilayer sample. Odagri, "Optical multi- mode frequency-domain reflectome- ter," Opt. Tanno, "High-resolution reflectometry by optical multidigitized coherence," Optical Review 3, Tanno, "Optical reflection-intensity-distribu- tion reproduction based on the de- tection of interference spectrum distribution-a direct detection method," Rev. Tanno, "Optical reflec- tion-intensity-distribution reproduc- tion based on the detection of inter- ference spectrum distribution-a phase sensitive interference coinpo- nent detection method," Rev. Tanno, "Multimode laser reflectome- try using a multi-channel analyzer," International Laser, Lightwave and Microwave Conference Proceed- ings, The reflected light from the DUT interferes with a ref- erence light and is measured by fre- quency-analyzing the interference signal. The maximum mcasurcment range of the FMCW reflectometry is limited by the co- herence length of the light source and is typically 10 in when a laser diode is used as the light source. Here we report mid- range FMCW reflectometry using a narrow-linewidth laser diode with linearized optical frequency sweep. Figure 1 shows our experimental configuration. The optical frequency of the laser was swept by modulating the injection current by a symmetrical triangular signal. Measured reflection profile with and without linearizing the optical frequency sweep. In the FMCW reflectometry, the non- linearity in the optical frequency sweep degrades the spatial resolution,4 and this is usual when a laser diode is used as the light source because the optical frequency response of the laser diode lags be- hind the injection current change due to thermal effect. To linearize the optical frequency sweep of the laser, the rec- tangular signal synchronized with the modulating triangular signal was super- imposed on the triangular signal. This compensates for the response lag in the optical frequency change just after the turning points of the trianguiar signal, and consequently, linearize the optical frequency sweep. Figure 2 shows the measured reflection profile with and without the linearization. The reflection profile is nar- rowed by the linearization and the spatial resolution is improved. Figure 3 shows the measured reflection profile for two connected single-mode optical fibers 25 and 63 m single-mode optical fibers when the optical frequency sweep was linearized. The Rayleigh backscattering in the fibers as well as the reflections at the connector and the far end of the fiber were successfully measured. In conclusion, we have described a mid-range FMCW reflectometry using a narrow-linewidth DFB laser with linear- ized optical frequency sweep. The optical Fiber length m FP3 Fig. Measured reflection profile for single-mode optical fibers. The measurement range of 88 m for a single-mode optical fiber was achieved. Iiyama, E Tsukada, N. How- ever, the measurement accuracy of the displacement amplitude was found to decrease if the asymmetry of the sawtooth became small. In order to overcome the difficulty of the previous digital vibrometer, we pro- pose a new vibrometer using a self-mix- ing laser diode that is modulated with a triangular current. Although the previous range-finding speedomete? Schematic configuration of a measuring system. Page 1

2 Chapter 2 : Optical guidance of brain therapies â The University of Tennessee Health Science Center Previous Titles. 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR) Conference on Lasers and Electro-Optics Pacific Rim (CLEOPR). Een van de doelen die ik had bij mijn recente renovatie van het huis, was om elke gloeilamp in het huis te vervangen door een LED lamp. Omdat je weet dat het duur is, probeer je dat eigenlijk zoveel mogelijk te vermijden. Maar mensen hebben, vooral wanneer ze willen dat het de hele kamer of de hele tuin verlicht, toch goede verlichting nodig. Welke Lichten Gebruik Je Thuis? Jij hoeft niet zo ver te gaan, maar ik ben een beetje geobsedeerd! Het heeft me een paar jaar gekost om het goed te krijgen. Dit wordt gemeten in Kelvin je vindt het op het pakket van een gloeilamp. Ik houd van een warm wit, net als de ouderwetse gloeilampen. Dit is ongeveer Kelvin K. Het is interessant dat mensen uit koudere klimaten de voorkeur geven aan een warm licht, terwijl mensen uit warmere klimaten liever iets meer wit of blauw licht hebben. Nu ik begrijp hoe dat werkt met kleur vind ik elke keer de juiste verlichting. Halogeen spots hebben gemiddeld branduren, een spaarlamp LED inbouw spots zijn rustiger voor jouw ogen Ten opzichte van spaarlampen en TL-verlichting is opbouwspots led een stuk rustiger voor de ogen. Een ouderwetse TL-balk gaat meerdere keren per seconde aan en uit. Dit is goed waar te nemen als een spaarlamp of Tl-balk aan het eind van zijn levensduur is. Ideaal voor op kantoor of werkruimte aan huis. LED opbouw spots Zoekt u een alternatief voor de staande schemerlamp? LED opbouw spotjes zijn ideaal om een bepaalde ruimte of een hoek van de hiervoor bestemde verlichting te voorzien. Kies bij voorkeur voor led spots opbouw, welke je eenvoudig naar de gewenste sfeer kunt dimmen. Opbouw LED spots zijn eenvoudig te plaatsen en makkelijker te richten dan de inbouw LED spots, dit doordat ze niet in het plafond zijn weggewerkt maar juist erop. Een LED opbouw spot wordt nauwelijks warm wat een groot voordeel is ten opzichte van de traditionele lichtbronnen. Je kunt met een gerust hart de LED opbouw spots op het plafond plaatsen zonder dat er brandgevaar ontstaat. En omdat de LED opbouw spot niet warm wordt is het ook een stuk kindvriendelijker. Door middel van een RGB-kleuren voor de LED inbouwspot kun je bepaalde objecten of ruimtes in jouw interieur op een stijlvolle manier uitlichten. LED inbouwspots zonder UV-straling Traditionele verlichting geeft een bepaalde mate aan ultraviolette straling af. Bij LED opbouwspots is dat niet het geval. Page 2

3 Chapter 3 : LASERS AND ELECTRO-OPTICS PACIFIC RIM. CONFERENCE. (CLEO-PR ) (2 VOLS) Get this from a library! CLEO/Pacific Rim ' the Pacific Rim Conference on Lasers and Electro-optics, Nippon Convention Center, Makuhari Messe, Chiba, Japan, July ; co-located with InterOpto ' technical digest. The finite sample ensemble averages for the normally-ordered photon number vari- ances were checked for convergence with respect to discretization and sampling errors. The significance of these newly ob- tained results is multifold. First, they clearly demonstrate the importance of quantum noise in macroscopic systems. We have analyzed a nonlinear device constructed from a single-mode wave- guide which conserve photon number- a fiber with an intensity dependent Kerr response-and shown that it gives rise to large photon-number fluctuations at its output. In addition, we have shown that another nonlinear device with a similar nonlinear response-a soliton nonlinear spectral-filter with the same soliton input pulses traveling the same number of soliton periods-leads to sub-shot-noise photon number fluctuations. Clearly the classical nonlinear input-output relation is not enough to predict the quantum noise properties of the output pulses. Doran, David Wood, Opt. Levanon, Takaaki Mukai, Phys. For details of the computational meth- ods, see http: We recognize the need to develop sensors of this sort which pro- vide a direct absolute calibration stan- dard with high accuracy and reliability and which can be compared with other known calibration standards techniques, but provide an absolute standard in their own right. Our uses for such sensors in- clude stand-alone instrumentation as well as instrumented laser OEM applications. We have utilized pyroelectric and thermal disk technology to develop these sensors. We discuss the criteria consid- ered and the numerous approaches used to design and fabricate these primary standards. A comprehensive model of the sensor physics and performance has been developed to aid in sensor design and evaluation as well as to establish sensor error contributions. Data taken on the final configurations for each device is com- pared to this model and to a variety of US. We present our results along with some conclusions we have drawn with regard to the accuracy of these devices when used as absolute laser energy and power calibration standards. A brief review of work by other researchers in this area will also be provided. The direct control method of spa- tial mode control is allowed by wave- guide structures including fibers. For the laser diode pumping the absorption CO- efficient is essential contrary to the solar pumping. However, the optical thickness of fiber lasers is low under the side pumping geometry. However, if fibers WB2 Fig. Various design of fiber embedded tube and disk lasers. We propose two types of fiber-embedded lasers, a tube and a disk style as shown in Fig. The tube laser is composed from a bobbin of hundreds of single-clad fibers with rare-earth doped cores. Although the pumping geometry is similar to the conventional rod lasers, the lasing output is confined in the end of the fibers. Two- dimensional LD arrays illuminate the tube in the side pumping geometry. The ends of the fibers are uncoated because the total efficiency is higher. The outputs of fibers are combined incoherently in a manner of fiber bundle. For the disk-style lasers, fiber lasers are embedded in the thin disk in a spiral mode. The fiber-embedded optical disk is formed through an immersing process of UV-cured polymer which is the same ma- terial with clad. The upper and lower surfaces are coated by metallic coating to confine the pumping power from the edge of the disk. The LD bars are con- nected to the edge, and the fiber disk is excited from the edge. The optical thickness of this disk is thick enough. The ef- fective absorption coefficient is deter- mined by the doping concentration and the ratio of core and clad diameter. The clad pumping scheme is also pos- sible if the pumping beams are injected in the oblique mode. The pumping power circulates the optical disk in a manner of storage ring. In this case the effective absorption coefficient is deter- mined by So, we can design the optimum condition of fibers and output power. Schematic diagram of the frequency stabilize system of the injection-locked laser. The injected light is introduced to the reference F. The injection lock technique is promising for realizing the high power with low frequency noise light source. In our study, we investigate the high fre- quency stabilization of the injection locked laser. YAG ring laser is made as a slave laser. The LD end-pumped solid state laser is cho- sen for our study because of its low intrinsic frequency and intensity noise Page 3

4 and high beam quality. The phase- locking servo keeps injection-locked os- cillation stable which controls the length of the slave laser cavity by means of two PZTs on which mirrors of the cavity are mounted; bandwidth of the phase lock- ing servo is 15 khz. The injected master laser power is 70 mw and the locking range of this injection-locked laser is measured to be 1. The frequency of the injection-locked laser is locked by Pound- Drever technique to a high finesse Fabry- Perot cavity which is suspended by double pendulum suspensions and is contained in the vacuum chamber to iso- late from the outside. The error signal from the servo circuit is fed back to both the master laser and the electro-optic modulator EOM1 which is inserted be- tween the master and the slave laser, and, in the consequence, total servo band- width of khz is obtained see Fig. The relative frequency noise spectrum of the injection-locked laser which is mea- sured from the error point signal is shown in Fig. A solid line shows the relative frequency noise spectrum of injection-locked laser, and the residual frequency noise spectrum between the master and the slave laser is shown as a dotted line. Such a high stabilization of the in- jection-locked laser has never been done before. The residual frequency noise of the injection-locked laser system is shown in Fig. From the results, at the range where the noise suppression gain is high, the frequency noise is suppressed as low as that of a master laser and the residual frequency noise of the injection-lock sys- tem is inclusively suppressed. On the other hand, the frequency noise above 10 khz is suffered from the residual fre- quency noise; some resonant peaks of the residual frequency noise is converted into the intensity noise of the injection-locked laser, and they result in some resonant peaks shown in the frequency noise spec- trum of the injection-locked laser. We developed the ultra-low loss mirror for frequency stabilization of solid state lasers in cooperation with the Jap- anese optical industries. As the best result until today, we reported the total loss including absorption and scattering loss of about 1. Such a high quality mirror was developed for mode cleaner cavity in which the beam diameter is less than 1 mm. However, the dimension of mirror components of m interferom- eter under construction in the National Astronomical Observatory is 10 cm in di- ameter or more. To achieve ultra-low loss of ppm or- der in the large aperture optical mirror, Reflectance and Scattering measurement of Fabry-Perot Cavity I O 0 1. Reflectance and scattering measured by ring-down methods. The scattering loss coefficients were measured for flat and concave mmors separately. We installed two integrated spheres in front of the mirrors of the Fabry-Perot cavity composed of flat and concave mirrors. The cavity en- hancement by high finesse properties al- lowed us to measure the low scattering coefficients with large intensity of signals. The result of ring-down measurement was shown in Fig. In this measure- ment, the signal intensity of scattering is independent to the scattering coefficient, because the input power is simply di- vided into the absorption and scattering. The resultant mapping of reflectance and scattering in Fig. This means the major part of fluctuation of reflectance at- Two-dimensional mapping of reflectance and scattering over the mirror made in the National Astronomical Observatory. The reflectance distribution was anti- correlated to the scattering distribution. Chapter 4 : CLEO Pacific Rim CLEO/Pacific Rim ' The Pacific Rim Conference on Lasers and Electro-optics, Nippon Convention Center, Makuhari Messe, Chiba, Japan, July with InterOpto '97 technical digest Published by IEEE Service Center. Chapter 5 : Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR) CLEO/PR provides a forum for an update and review of a wide range of lasers and electro-optics disciplines from device development to systems engineering and applications. The meeting also serves to stimulate the use of more mature optical technologies in other fields. Chapter 6 : OSA Conference on Lasers and Electro-Optics/Pacific Rim Page 4

5 â The 12th Conference on Lasers and Electro-Optics Pacific Rim(CLEO-PR ) â The 22nd OptoElectronics and Communications Conference (OECC ) â The 5th Photonics Global Conference (PGC ). Chapter 7 : 14th Pacific Rim Conference on Lasers and Electro-Optics CLEO-PR The 14th Pacific Rim Conference on Lasers and Electro-Optics (CLEO Pacific Rim, CLEO-PR ) will be held at the International Convention Centre, Sydney, Australia from 2 to 6 August Chapter 8 : OSA Conference on Lasers and Electro-Optics/Pacific Rim The 13th Pacific Rim Conference on Lasers and Electro-Optics (CLEO Pacific Rim, CLEO-PR ) will be held at the Hong Kong Convention and Exhibition Centre, Hong Kong SAR from 29 July to 3 August Chapter 9 : CLEO Pacific Rim Conference Industry Events blog.quintoapp.com The 14th Pacific Rim Conference on Lasers and Electro-Optics (CLEO Pacific Rim, CLEO-PR ) will be held at the International Convention Centre, Sydney, Australia from 2 to 6 August Simin Li, Nanjing University of Aeronautics and Astronautics, China. Page 5