IEEE NANO 2011

Development of a Versatile Near Field Optical Imaging System
Derek Nowak, Portland State University Portland, Oregon
Co-Authors: Justin Hiester, Deepak Vedhachalam, Zechariah K. Dzegede, Erik J. Sánchez

The ability to detect optical information from optically active systems with resolutions below the diffraction limit of traditional light microscopes is of great interest of biologist and material scientists. Using the technique of Tip Enhanced Near-field Optical Microscopy, or (TENOM) (Sánchez, PRL. 1999), fluorescence imaging with ~20 nm resolution has shown to be possible. TENOM demonstrates these optical resolutions with simultaneous topographical information as well as the ability to detect with both electronic state and vibrational bond (Raman) information for single-molecule level identification. TENOM utilizes an Atomic Force Microscopy (AFM) scanning method where the imaging probe has been modified to create a localized field enhancement. The microscopes ability to image in solution is an additional feature. Unfortunately, TENOM has not seen common day use as a research tool, due primary to the level of understanding needed by the user to create suitable probes and correctly operate the microscope. Our goal has been to develop a TENOM based microscope controlled by a single low cost computer, simple control circuits using FPGA data acquisition, and simplified optical system allowing for imaging with photons from almost any visible chromophore without changing filters or excitation wavelength. Our system will be an open source system design, using only off the shelf available components. This instrument will improve upon the nominal 75 nm resolution limit of todays Near Field Scanning Microscopes.

Erik Sanchez
Interests: Development and implementation of nano-scale imaging techniques. Study of the optical interaction of light and nanometric objects in order to generate enhanced fields for fluorescence and Raman spectroscopy/microscopy. Determination of new applications for Focused Ion / Electron Beam systems towards the study of biological systems using near-field and far-field microscopies.

Derek Nowak
Physics Research Odyssey Near-Field Microscopy Multi-Photon Imaging ANSOM Project FDTD Modeling MPI Clustering LMIS Development Classes
Near-Field Microscopy
Motivation: To obtain florescence images of biological and material systems at spatial resolutions significantly lower than the diffraction limit. This technique has demonstrated optical imaging resolutions of ~40 nanometers, at room temperature and atmospheric pressure.
Side profiles of a near-field aperture probe and apertureless probe scanning over fluorescing chromophores. A fiber optic cable is tapered to a small point via chemical etching and coated with metal to confine light sent down the fiber (aperture)(Pohl, Lewis, Betzig). The light is typically collected below by the high numerical lens and directed to a photon detector in the far field.

Terahertz systems, set ups and components New band pass and long pass THz optical filters based on porous silicon and metal mesh technologies. Band pass filters with center wavelengths from 30 THz into GHz range and transmissions up to 80% or better. Standard designs with clear aperture diameters from 12.5 to 37.5 mm. Long pass filters with standard rejection edge wavelengths from 60 THz into GHz range. Maximum transmission up to 80% or better, standard designs at 19.0 and 25.4 mm diameters. Excellent thermal (from cryogenic to 600 K) and mechanical properties

Need complet THz set up? Check different options available from Del Mar Photonics or e-mail us for custom set up! Ready to buy complet THz Spectrometer? Trestles Pacifica THz Time Domain Spectrometer is a modular tabletop system for scientific and industrial applications of pulsed THz radiation.

	Trestles LH Ti:Sapphire laser Trestles LH is a new series of high quality femtosecond Ti:Sapphire lasers for applications in scientific research, biological imaging, life sciences and precision material processing. Trestles LH includes integrated sealed, turn-key, cost-effective, diode-pumped solid-state (DPSS). Trestles LH lasers offer the most attractive pricing on the market combined with excellent performance and reliability. DPSS LH is a state-of-the-art laser designed for today’s applications. It combines superb performance and tremendous value for today’s market and has numerous advantages over all other DPSS lasers suitable for Ti:Sapphire pumping. Trestles LH can be customized to fit customer requirements and budget. Reserve a spot in our Femtosecond lasers training workshop in San Diego, California. Come to learn how to build a femtosecond laser from a kit
	DPSS DMPLH lasers DPSS DMP LH series lasers will pump your Ti:Sapphire laser. There are LH series lasers installed all over the world pumping all makes & models of oscillator. Anywhere from CEP-stabilized femtosecond Ti:Sapphire oscillators to ultra-narrow-linewidth CW Ti:Sapphire oscillators. With up to 10 Watts CW average power at 532nm in a TEMoo spatial mode, LH series lasers has quickly proven itself as the perfect DPSS pump laser for all types of Ti:Sapphire or dye laser. Ideal for pumping of: Trestles LH Ti:Sapphire laser T&D-scan laser spectrometer based on narrow line CW Ti:Sapphire laser
	New laser spectrometer T&D-scan for research that demands high resolution and high spectral density in UV-VIS-NIR spectral domains - now available with new pump option! The T&D-scan includes a CW ultra-wide-tunable narrow-line laser, high-precision wavelength meter, an electronic control unit driven through USB interface as well as a software package. Novel advanced design of the fundamental laser component implements efficient intra-cavity frequency doubling as well as provides a state-of-the-art combined ultra-wide-tunable Ti:Sapphire & Dye laser capable of covering together a super-broad spectral range between 275 and 1100 nm. Wavelength selection components as well as the position of the non-linear crystal are precisely tuned by a closed-loop control system, which incorporates highly accurate wavelength meter. Reserve a spot in our CW lasers training workshop in San Diego, California. Come to learn how to build a CW Ti:Sapphire laser from a kit
	AOTF Infrared Spectrometer Del Mar Photonics offer a handheld infrared spectrometer based on the acousto-optic tunable filter (AOTF). This instrument is about the size and weight of a video camera, and can be battery operated. This unique, patented device is all solid-state with no moving parts. It has been sold for a wide variety of applications such as liquid fuel analysis, pharmaceutical analysis, gas monitoring and plastic analysis. Miniature AOTF infrared spectrometer uses a crystal of tellurium dioxide to scan the wavelength. Light from a light source enters the crystal, and is diffracted into specific wavelengths. These wavelengths are determined by the frequency of the electrical input to the crystal. Since there are no moving parts, the wavelength scanning can be extremely fast. In addition, specific wavelengths can be chosen by software according to the required algorithm, and therefore can be modified without changing the hardware. After the infrared radiation reflects off of the sample, it is converted into an electrical signal by the detector and analyzed by the computer. Del Mar Photonics is looking for international distributors for RAVEN - AOTF IR spectrometer for plastic identification and for variety of scientific and industrial collaborations to explore futher commercial potential of AOTF technology.
	Open Microchannel Plate Detector MCP-MA25/2 - now in stock! Microchannel Plate Detectors MCP-MA series are an open MCP detectors with one or more microchannel plates and a single metal anode. They are intended for time-resolved detection and make use of high-speed response properties of the MCPs. MCP-MA detectors are designed for photons and particles detection in vacuum chambers or in the space. MCP-MA detectors are used in a variety of applications including UV, VUV and EUV spectroscopy, atomic and molecular physics, TOF mass–spectrometry of clusters and biomolecules, surface studies and space research. MCP-MA detectors supplied as a totally assembled unit that can be easily mounted on any support substrate or directly on a vacuum flange. They also can be supplied premounted on a standard ConFlat flanges. buy online - ask for research discount!
	Hummingbird EMCCD camera The digital Hummingbird EMCCD camera combines high sensitivity, speed and high resolution. It uses Texas Instruments' 1MegaPixel Frame Transfer Impactron device which provides QE up to 65%. Hummingbird comes with a standard CameraLink output. It is the smallest and most rugged 1MP EMCCD camera in the world. It is ideally suited for any low imaging application such as hyperspectral imaging, X-ray imaging, Astronomy and low light surveillance. It is small, lightweight, low power and is therefore the ideal camera for OEM and integrators. buy online
	Hatteras-D femtosecond transient absorption data acquisition system Future nanostructures and biological nanosystems will take advantage not only of the small dimensions of the objects but of the specific way of interaction between nano-objects. The interactions of building blocks within these nanosystems will be studied and optimized on the femtosecond time scale - says Sergey Egorov, President and CEO of Del Mar Photonics, Inc. Thus we put a lot of our efforts and resources into the development of new Ultrafast Dynamics Tools such as our Femtosecond Transient Absorption Measurements system Hatteras. Whether you want to create a new photovoltaic system that will efficiently convert photon energy in charge separation, or build a molecular complex that will dump photon energy into local heat to kill cancer cells, or create a new fluorescent probe for FRET microscopy, understanding of internal dynamics on femtosecond time scale is utterly important and requires advanced measurement techniques. Reserve a spot in our Ultrafast Dynamics Tools training workshop in San Diego, California.
	Beacon Femtosecond Optically Gated Fluorescence Kinetic Measurement System - request a quote - pdf Beacon together with Trestles Ti:sapphire oscillator, second and third harmonic generators. Femtosecond optical gating (FOG) method gives best temporal resolution in light-induced fluorescence lifetime measurements. The resolution is determined by a temporal width of femtosecond optical gate pulse and doesn't depend on the detector response function. Sum frequency generation (also called upconversion) in nonlinear optical crystal is used as a gating method in the Beacon femtosecond fluorescence kinetic measurement system. We offer Beacon-DX for operation together with Ti: sapphire femtosecond oscillators and Beacon-DA for operation together with femtosecond amplified pulses. Reserve a spot in our Ultrafast Dynamics Tools training workshop in San Diego, California.
	Terahertz systems, set ups and components New band pass and long pass THz optical filters based on porous silicon and metal mesh technologies. Band pass filters with center wavelengths from 30 THz into GHz range and transmissions up to 80% or better. Standard designs with clear aperture diameters from 12.5 to 37.5 mm. Long pass filters with standard rejection edge wavelengths from 60 THz into GHz range. Maximum transmission up to 80% or better, standard designs at 19.0 and 25.4 mm diameters. Excellent thermal (from cryogenic to 600 K) and mechanical properties Need complet THz set up? Check different options available from Del Mar Photonics or e-mail us for custom set up! Ready to buy complet THz Spectrometer? Trestles Pacifica THz Time Domain Spectrometer is a modular tabletop system for scientific and industrial applications of pulsed THz radiation.
	iPCA - interdigital Photoconductive Antenna for terahertz waves Large area broadband antenna with lens array and high emitter conversion efficiency iPCA with LT-GaAs absorber, microlens array for laser excitation wavelengths l £ 850 nm, adjusted hyperhemispherical silicon lens with a high power conversion efficiency of 0.2 mW THz power / W optical power. The iPCA can be used also as large area THz detector. The two types iPCAp and iPCAs have the same active interdigital antenna area but different contact pad directions with respect to the electrical THz field. Interdigital Photoconductive Antenna for terahertz waves generation using femtosecond Ti:Sapphire laser THz books
	IntraStage lowers the cost of test data management! Struggling with gigabytes or terabytes of test data? IntraStage easily transforms test data from disparate sources into web-based quality metrics and engineering intelligence you can use. Contact us today to discuss your test management requirements and specifications of your application.

	Rutile (TiO2) coupling prisms Del Mar Photonics offers optical elements made of high quality synthetically grown Rutile Titanium Dioxide crystals. Rutile’s strong birefringency, wide transmission range and good mechanical properties make it suitable for fabrication of polarizing cubes, prisms and optical isolators. Boules having high optical transmission and homogeneity are grown by proprietary method. Typical boules have 10 - 15 mm in dia. and up to 25 mm length. Optical elements sizes - from 2 x 2 x 1 mm to 12.7 x 12.7 x 12.7 mm. Laser grade polish quality is available for finished elements. So far we the largest elements that we manufactured are 12 x15 x 5 mm, in which optical axis is parallel to 15 mm edge, 5 mm is along beam path, 12 x 15 mm faces polished 20/10 S/D, one wave flatness, parallelism < 3 arc.min. (better specs. available on request). more details - download brochure - request a quote
	Vacuum viewport Del Mar Photonics offer a range of competitively priced UHV viewports , Conflat, ISO or KF including a variety of coatings to enhance performance. Del Mar Photonics viewports are manufactured using advanced techniques for control of special and critical processes, including 100 percent helium leak testing and x-ray measurements for metallization control. Windows Materials include: Fused silica, Quartz , Sapphire , MgF2, BaF2, CaF2, ZnSe, ZnS, Ge, Si, Pyrex. Standard Viewing diameters from .55" to 1.94 ". Coating - a range of custom coatings can applied - which include - Single QWOT - Broad Band AR - V coatings - ITO - DLC (Diamond like coating) more details - request a quote
	Hydrogen Thyratrons are used in such devices as radars with different power levels, high-power pulsed technical, electrophysical, medical devices and lasers. Sophisticated design and high quality ceramic-metal envelope determines long lifetime and very accurate and reliable operation of hydrogen thyratrons under wide range of environmental conditions. Applications: - radars - pulsed lasers power supplies - medical apparatus - electrophysical instrumentation Triggered Three-Electrode Spark Gap Switches are ceramic-metal sealed off gas discharge trigatron-type devices with a co-axial trigger electrode. These Gas Discharge Tubes contain no mercury and, due to an advanced design, feature high reliability and a long lifetime being operating under wide range of environmental conditions. Applications: - pulsed installation for processing materials - installations with plasma focus - pulse power supplies for lasers and other pulse equipment - medical apparatus such as lithotriptors and defibrillators - processing systems for petroleum wells