السلام عليكم
اليكم هذا العددمن مجلة
Laser Focus World Magazine ~ Volume 45 Issue 1 January, 2009
Table of Contents
=============
Newsbreaks
Holmium-doped glass ceramics enhance silicon solar-cell efficiency
Solar cells fabricated from silicon can benefit from a photon upconversion (UC) process in which two or more low-energy photons are converted to a higher-energy photon.
Polariton waveguide has low bending loss
Long-range surface-plasmon polaritons (LRSPPs), which are electron disturbances at a metal surface resulting from interactions with light, may become a practical way to transmit optical information in commercial devices such as mobile phones.
Femtosecond pulses create microlenses in glass
Direct femtosecond laser writing is emerging as an alternative technique to lithography for fabrication of microstructures inside transparent materials.
Ultrafast laser creates photonic crystal in diamond
A metamaterial consisting of periodic regions of high electrical conductivity in a 3 × 3 × 1.5 mm synthetic-diamond crystal has been fabricated by researchers at Kyoto University (Kyoto, Japan); the regions are created by focusing 230 fs pulses at 1 kHz from a modelocked Ti:sapphire laser to a beam-waist diameter of 2 µm and an energy fluence of 28.5 J/cm2 within the crystal.
Audience interaction with ‘hologram’ enabled by spinning-mirror system
The Institute for Creative Technologies (ICT) at the University of Southern California (Los Angeles, CA) has developed a “hologram-like” 3-D videoconferencing system.
Infrared quantum-cascade detector has broad spectral response
Infrared quantum-cascade detectors (QCDs) with high detectivities tend to have narrow spectral linewidths, due to the means of detection (optical bound-to-bound transitions).
MEMS obscura telescope tracks fast objects
A novel pinhole-type camera that substitutes a microelectromechanical systems (MEMS)-based micromirror array for the pinhole has been developed by the Research Center of MEMS Space Telescope at Ewha Womans University (Seoul, Korea) with their collaborators at Seoul National University (Seoul, Korea), Pusan National University (Pusan, Korea), and Moscow State University (Moscow, Russia).
Talbot external cavity coherently combines ten laser diodes
A method of phase-locking an array of ten index-guided tapered laser diodes has been devised by researchers at CNRS and the Alcatel-Tales III-V Lab (both in Palaiseau, France) and the University of Nottingham (Nottingham, England).
Focal-modulation microscopy improves deep-tissue imaging
Although confocal microscopy (CM) is effective for subcellular imaging to depths of tens of microns (and for imaging fluorescently tagged tissues, unlike optical-coherence tomography), attempts to image deeper molecular structures using CM are usually disrupted by scattered photons.
World News
WIDE-ANGLE OPTICS: Panoramic imager captures an unoccluded 260°
Using only two optical components, researchers from Bielefeld University (Bielefeld, Germany), the Australian National University (Canberra, Australia), and the University of Queensland (St. Lucia, Australia), have created a panoramic imager that fits over a standard 6 mm C-mount lens for a 1/2 in.
CMOS SENSORS: Optical confinement enables CMOS-sensor scaling
As the demand for higher-resolution complementary metal-oxide semiconductor (CMOS) image sensors continues to increase for cell-phone and digital-camera applications, shrinking CMOS pixel sizes present new challenges for sensor designers.
PHOTOVOLTAICS: Optical modeling determines luminescent solar-concentrator efficiency
A multi-institutional team of researchers, working through the FULLSPECTRUM project of the European Commission, has published encouraging research results from a five-year investigation of emerging luminescent solar-concentrator (LSC) materials and methodology for downconverting broad-spectrum solar radiation into the spectral-sensitive windows of silicon solar cells.
WHITE-LIGHT LEDS: Pitted LEDs emit broad spectra
Two types of phosphor-free white-emitting LEDs have been developed that appear, at first glance, to rely on the same concept for white-light emission; however, when examined in detail, they are different.
OPTICAL COMMUNICATIONS: Plasmonic LED approaches 10 GHz modulation speed
Commercial light-emitting diodes (LEDs) are only capable of 1 GHz maximum modulation speeds because of slow carrier recombination, limiting them to applications in short-haul optical communication links.
CCDS AND MICROSCOPY: Real-time 3-D microscopy enables viewing of specimen dynamics
Because a standard confocal microscope efficiently images only regions of a specimen that lie close to the focal plane, producing a 3-D depiction requires that the microscope refocus and image a series of closely spaced planes.
MID-IR OPTICAL FIBERS: Silver halide modal filter to help find exoplanets
An improved form of an optical component called a modal filter has been developed by researchers at the Jet Propulsion Laboratory (JPL; Pasadena, CA) and Tel Aviv University (TAU; Tel Aviv, Israel); the filter, which takes the form of a single-mode silver halide optical fiber, is intended to aid the search for life outside the Solar System.
BEAM COMBINING: Digital holography combines optical-fiber beams coherently
Tremendous strides have been made in increasing the output power of single-mode fiber lasers.
PLASMONICS: Surface plasmons switched at terahertz rates
The field of so-called active plasmonics has seen an unprecedented leap in switching times, thanks to the favorable properties of aluminum and the efforts of a number of researchers at the University of Southampton (Southampton, England) in collaboration with an academic at Georgia State University (Atlanta, GA).
RAMAN SPECTROSCOPY: Nanowire on a film makes efficient SERS platform
Researchers from KAIST (Daejeon, Korea), Korea University, and Soongsil University (both in Seoul, Korea), have developed an efficient and highly reproducible surface-enhanced Raman spectroscopy (SERS) platform for scattering-based sensors in biological and medical applications.
Features
PHOTONICS APPLIED: ATMOSPHERIC MONITORING: New photonic devices boost environmental monitoring capabilities
In our increasingly “green” world, the need for portable and accurate atmospheric monitoring equipment, in which photonics plays a significant role, has expanded as society weighs the environmental effects of toxic chemicals and greenhouse gases.
FTIR SPECTROSCOPY: Optical cavity boosts broadband FTS sensitivity
High-resolution Fourier-transform cavity-enhanced absorption spectroscopy in the near-IR gains wide spectral coverage from an incoherent broadband light source.
PHOTONIC FRONTIERS: MATERIALS FOR SOLID-STATE LASERS: New materials expand capabilities of solid-state lasers
Ceramic hosts, transition-metal doping of II-VI hosts, and optically pumped semiconductor lasers are expanding the range of solid-state laser capabilities to new wavelengths and higher powers.
ADAPTIVE OPTICS: Fluorescent microspheres enable adaptive-optics microscopy
Adaptive optics has tantalized researchers looking for ways to image through thick biological tissue–but the approach is not straightforward.
DIFFRACTIVE OPTICS: Harmonic optical element simplifies Blu-ray optics
A harmonic optical element added behind the objective lens of a Blu-ray pickup allows it to handle Blu-ray, DVD, and CD wavelengths with a single optical system.
PRODUCT FOCUS: POWER SUPPLIES: Laser-diode power-supply basics: performance depends on specification
Bench-top laser-diode drivers and controllers have a wide variety of features, from voltage and temperature control to safety features and surge protection.
حمل من
http://rapidshare.com/files/187508771/LFW_20090101_Jan_2009a.rar
اليكم هذا العددمن مجلة
Laser Focus World Magazine ~ Volume 45 Issue 1 January, 2009
Table of Contents
=============
Newsbreaks
Holmium-doped glass ceramics enhance silicon solar-cell efficiency
Solar cells fabricated from silicon can benefit from a photon upconversion (UC) process in which two or more low-energy photons are converted to a higher-energy photon.
Polariton waveguide has low bending loss
Long-range surface-plasmon polaritons (LRSPPs), which are electron disturbances at a metal surface resulting from interactions with light, may become a practical way to transmit optical information in commercial devices such as mobile phones.
Femtosecond pulses create microlenses in glass
Direct femtosecond laser writing is emerging as an alternative technique to lithography for fabrication of microstructures inside transparent materials.
Ultrafast laser creates photonic crystal in diamond
A metamaterial consisting of periodic regions of high electrical conductivity in a 3 × 3 × 1.5 mm synthetic-diamond crystal has been fabricated by researchers at Kyoto University (Kyoto, Japan); the regions are created by focusing 230 fs pulses at 1 kHz from a modelocked Ti:sapphire laser to a beam-waist diameter of 2 µm and an energy fluence of 28.5 J/cm2 within the crystal.
Audience interaction with ‘hologram’ enabled by spinning-mirror system
The Institute for Creative Technologies (ICT) at the University of Southern California (Los Angeles, CA) has developed a “hologram-like” 3-D videoconferencing system.
Infrared quantum-cascade detector has broad spectral response
Infrared quantum-cascade detectors (QCDs) with high detectivities tend to have narrow spectral linewidths, due to the means of detection (optical bound-to-bound transitions).
MEMS obscura telescope tracks fast objects
A novel pinhole-type camera that substitutes a microelectromechanical systems (MEMS)-based micromirror array for the pinhole has been developed by the Research Center of MEMS Space Telescope at Ewha Womans University (Seoul, Korea) with their collaborators at Seoul National University (Seoul, Korea), Pusan National University (Pusan, Korea), and Moscow State University (Moscow, Russia).
Talbot external cavity coherently combines ten laser diodes
A method of phase-locking an array of ten index-guided tapered laser diodes has been devised by researchers at CNRS and the Alcatel-Tales III-V Lab (both in Palaiseau, France) and the University of Nottingham (Nottingham, England).
Focal-modulation microscopy improves deep-tissue imaging
Although confocal microscopy (CM) is effective for subcellular imaging to depths of tens of microns (and for imaging fluorescently tagged tissues, unlike optical-coherence tomography), attempts to image deeper molecular structures using CM are usually disrupted by scattered photons.
World News
WIDE-ANGLE OPTICS: Panoramic imager captures an unoccluded 260°
Using only two optical components, researchers from Bielefeld University (Bielefeld, Germany), the Australian National University (Canberra, Australia), and the University of Queensland (St. Lucia, Australia), have created a panoramic imager that fits over a standard 6 mm C-mount lens for a 1/2 in.
CMOS SENSORS: Optical confinement enables CMOS-sensor scaling
As the demand for higher-resolution complementary metal-oxide semiconductor (CMOS) image sensors continues to increase for cell-phone and digital-camera applications, shrinking CMOS pixel sizes present new challenges for sensor designers.
PHOTOVOLTAICS: Optical modeling determines luminescent solar-concentrator efficiency
A multi-institutional team of researchers, working through the FULLSPECTRUM project of the European Commission, has published encouraging research results from a five-year investigation of emerging luminescent solar-concentrator (LSC) materials and methodology for downconverting broad-spectrum solar radiation into the spectral-sensitive windows of silicon solar cells.
WHITE-LIGHT LEDS: Pitted LEDs emit broad spectra
Two types of phosphor-free white-emitting LEDs have been developed that appear, at first glance, to rely on the same concept for white-light emission; however, when examined in detail, they are different.
OPTICAL COMMUNICATIONS: Plasmonic LED approaches 10 GHz modulation speed
Commercial light-emitting diodes (LEDs) are only capable of 1 GHz maximum modulation speeds because of slow carrier recombination, limiting them to applications in short-haul optical communication links.
CCDS AND MICROSCOPY: Real-time 3-D microscopy enables viewing of specimen dynamics
Because a standard confocal microscope efficiently images only regions of a specimen that lie close to the focal plane, producing a 3-D depiction requires that the microscope refocus and image a series of closely spaced planes.
MID-IR OPTICAL FIBERS: Silver halide modal filter to help find exoplanets
An improved form of an optical component called a modal filter has been developed by researchers at the Jet Propulsion Laboratory (JPL; Pasadena, CA) and Tel Aviv University (TAU; Tel Aviv, Israel); the filter, which takes the form of a single-mode silver halide optical fiber, is intended to aid the search for life outside the Solar System.
BEAM COMBINING: Digital holography combines optical-fiber beams coherently
Tremendous strides have been made in increasing the output power of single-mode fiber lasers.
PLASMONICS: Surface plasmons switched at terahertz rates
The field of so-called active plasmonics has seen an unprecedented leap in switching times, thanks to the favorable properties of aluminum and the efforts of a number of researchers at the University of Southampton (Southampton, England) in collaboration with an academic at Georgia State University (Atlanta, GA).
RAMAN SPECTROSCOPY: Nanowire on a film makes efficient SERS platform
Researchers from KAIST (Daejeon, Korea), Korea University, and Soongsil University (both in Seoul, Korea), have developed an efficient and highly reproducible surface-enhanced Raman spectroscopy (SERS) platform for scattering-based sensors in biological and medical applications.
Features
PHOTONICS APPLIED: ATMOSPHERIC MONITORING: New photonic devices boost environmental monitoring capabilities
In our increasingly “green” world, the need for portable and accurate atmospheric monitoring equipment, in which photonics plays a significant role, has expanded as society weighs the environmental effects of toxic chemicals and greenhouse gases.
FTIR SPECTROSCOPY: Optical cavity boosts broadband FTS sensitivity
High-resolution Fourier-transform cavity-enhanced absorption spectroscopy in the near-IR gains wide spectral coverage from an incoherent broadband light source.
PHOTONIC FRONTIERS: MATERIALS FOR SOLID-STATE LASERS: New materials expand capabilities of solid-state lasers
Ceramic hosts, transition-metal doping of II-VI hosts, and optically pumped semiconductor lasers are expanding the range of solid-state laser capabilities to new wavelengths and higher powers.
ADAPTIVE OPTICS: Fluorescent microspheres enable adaptive-optics microscopy
Adaptive optics has tantalized researchers looking for ways to image through thick biological tissue–but the approach is not straightforward.
DIFFRACTIVE OPTICS: Harmonic optical element simplifies Blu-ray optics
A harmonic optical element added behind the objective lens of a Blu-ray pickup allows it to handle Blu-ray, DVD, and CD wavelengths with a single optical system.
PRODUCT FOCUS: POWER SUPPLIES: Laser-diode power-supply basics: performance depends on specification
Bench-top laser-diode drivers and controllers have a wide variety of features, from voltage and temperature control to safety features and surge protection.
حمل من
http://rapidshare.com/files/187508771/LFW_20090101_Jan_2009a.rar
