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Words containing gelsoli
Found 1 words containing gelsoli. Browse our Scrabble Word Finder, Words With Friends cheat dictionary, and WordHub word solver to find words that contain gelsoli. Or use our Unscramble word solver to find your best possible play! Related: Words that start with gelsoli
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Discussion in 'Lawn Mowing' started by MowingMowingMowing, Jan 26, 2011.
Thanks JayD, appreciate all your help!
I really haven't been keeping up with this thread... I got a question though.... I have an open trailer and the only place I can put the sign is on the rear, some have mentioned it being bad on mileage, is it really that bad? I don't drive a ton so I really don't think it will account for much, just curious as to what people have experienced.
Those are two of the funniest comments that I have seen on here in a while...
JayD is spot on about over building anything on your trailer because if any equipment comes off during an accident (or worse yet just driving down the road) and hits a bystander your business is usually history along with all your hard earned personal assets. (unless your a Corp or a LLC)
I can feel a little difference with mine, but mine is a is some what big. But I don't think it will make that much difference.
Paid 50$ for my 2*3.
Where are you guys getting these made?
I have a few yards signs made a few years ago and decieded to zip tie one to the gate of my trailer... it lasted for a while until the wind ripped the sign where the zip tie holes were.


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It's a work in progress but during the re-sort I came across some stamps I carved for an article for Simply Cards and Papercraft issue 108 way back in 2012, although the magazine itself came out in 2013. I know! It is kind of making my eyes water just thinking about how long ago that was.
[There are some affiliate links in this blog post, so if you buy through them I do get a small amount of money at no extra cost to yourself. Thanks for your support!]
I don't even think you can get the magazine any more it was that long ago. But I thought it would be fun to ink up the stamps again and make a couple of new cards with them. What do you think? Have the designs aged well? They are pretty naive but I quite like that style.
I have used them for a couple of other projects one on my blog which was an art journal page and for a stamp carving tutorial over on the Blitsy blog, although I carved a new leaf for that project to the one I used in the magazine.
These stamps are made from Speedball Speedy Carve and Soft Cut Lino but I have also carved stamps into erasers before as well.
You know, this project revisit is making my want to do some new stamp carving! There is something really satisfying about carving your own stamp designs although I would not say I was that good at it. There are some truly phenomenal stamp carvers who share the work on instagram.
For instance I love the work of Viktoria Åström, her work is gorgeous and so detailed, you can see her on instagram or on her website. She often uses nature to inspire her work but her designs have so much character too, so do go check her out!
I quite like using double printing and that is how I made the chequered background. They are two different stamps, one I covered a square grid into and the other that I carved a line grid but you can layer them to make the chequered pattern.
The leaves are also a double print and if you pop over to my tutorial on the Blitsy blog you can see exactly how I made that print.
Another handy tip if you do use the Speedball Speedy Carve or erasers to carve into, they are thick enough to cover a stamp on both sides so two for the price of one. The Soft Cut Lino is much thinner, or at least the ones I have are, so you can only carve on one side.
So how about you? Do you carve your own stamps? What was the last design you carved? What do you use? Or do you have a favourite stamp carving artists?


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- Please select a date to see the proper prices!
- Meal can be requested on the spot
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201.52 € / person / night, no meal
Description of the accommodation:
Rooms, services Welcome to UNA Maison Milano Milan! We hope you will be satisfied the offers of the hotel, and will be happy to choose it as a resort to stay at. The hotel is offering 27 tasfefully furnished, nice rooms for those looking for a place to stay at in Milan. The bar is an ideal location for a personal meeting and a relaxing evening talk. In the safe your valuables can be the safely secured. Wireless Internet connection (WiFi) is available at the hotel, enabling portable devices and smartphones to go online. The exact list of services available at UNA Maison Milano Milan (including those for an extra fee) and the exact list of equipment in a room can be found on the information sheet below.
Payment Advance bank card payment or credit card guarantee may be required for the reservation, depending on the chosen date, room and price.
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Bathrobe, Hairdryer, Desk in the room, Mini-bar, Tea/coffee-maker


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Bobby Henderson
- Date of passing: Jul 12, 2015
|Let the memory of Bobby be with us forever
Mr. Bobby Henderson 71 of LaFayette, Alabama died Sunday July 12, 2015 at his residence.
Graveside services will be held Tuesday July 14, 2015 at 11AM (CT) 12PM (ET) at the LaFayette City Cemetery with the Rev. Paul Howard officiating.
Visitation will be held at the funeral home Monday from 5PM to 7PM (CT) 6PM to 8PM (ET).
Professional services provided by Jeff Jones Funeral Home of LaFayette, AL. www.jeffjonesfuneralhome.com
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MANUAL FOR TEACHING ASSISTANTS: Policies, Practices And …
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Shane Co.
6-7.5mm Cultured Freshwater Pearl and 4mm Amethyst Bead Bracelet (7.5")
Description & Specifications
This delightful bracelet features an alternating collection of both 6-7.5mm cultured freshwater pearls with 4mm purple amethyst beads. The bracelet is 7.5 inches long, secured by a clasp crafted of quality sterling silver, and has a one inch chain adjuster complete with a cultured freshwater pearl accent.
Item Number: 41072012
Item Number: 41072012
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- Pearl SizeMULTIPLE SIZES
- *Pearl ColorWhite
- Adjustable ChainYes
- Length7.5 inch
- Setting TypeNo Stones


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10 things to do during final CFA exam month.
Final month is the most crucial. During this month, managing yourself, your psychology is more important than preparing for the exam. Anxiety is at it\'s peak and most candidates, despite knowing the entire material,...
Valuing Bonds with Embedded Options
In this article, we will concentrate on callable bonds and putable bonds, although we'll mention prepayable and convertible bonds as well.
The common method of valuing a callable or putable bond is to use a binomial interest rate tree. For the examples that follow, we'll use the binomial tree we created here; it has 10% interest rate volatility:
Binomial Pricing Trees (for Options)
In this article, we'll be concerned with the application of binomial trees to the valuation of call and put options (on, for example, stocks or commodities).
Present Value of Growth Opportunities (PVGO)
Most companies don't remain the same size (i.e., have the same amount of earnings, net income) forever; with a soupçon of luck, a company's earnings will grow, year after year. The value of a company's opportunities to grow in the future is known, with no great originality, as the present value of growth opportunities (PVGO). Given the right information, calculating PVGO is trivial: it's the difference between the (present) value of the company as is (i.e., including those growth opportunities) and the (present) value of the company assuming zero growth:
Interest Rate Caps and Floors
Interest rate caps and floors are, essentially, collections of interest rate options: each option has a positive payoff when it expires in the money and a zero payoff when it expires out of the money. The individual options are called, respectively, caplets and floorlets.
Note that caps and floors are commonly based on LIBOR or similar floating interest rates; as such, they are governed by the usual LIBOR characteristics:
They are based on a 360-day year, with 30-day months
The interest rates are quoted as nominal, annual rates…
Creating a Binomial Interest Rate Tree
To create a binomial interest rate tree, you need to start with:
A yield curve
An interest rate volatility
The yield curve can be a par curve, a spot curve, or a forward curve. (If you're a bit fuzzy on the differences among these curves, look here.) For the remainder of this article, we'll assume that we're given a par curve; as we could generate the other curves given any one of them, it doesn't really matter which one we get.
Time Diversification & Impact on Capital Allocation Decisions: A Corporate Finance Perspective
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Importance Of Relative Valuation
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Inventory Methods: FIFO vs. LIFO vs. Average Cost vs. Specific Identification and Periodic vs. Perpetual
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Every inventory method has two important characteristics:
How will costs be assigned to cost of goods sold (COGS) and ending inventory (EI)?
When will those costs be assigned to COGS and EI?…


text: Human Rights Observatory Kenya Thwarts Militant Attack in Garissa County Kenyan officials say Islamic militants have attacked a village in northeastern Kenya, in the same area where militants seized control of a university and killed nearly 150 people last month. Kenya's interior ministry said Friday that militants attacked Yumbis village in Garissa county late Thursday, but were thwarted by security forces after a gun battle. No casualties have been reported. Al-Shabab militants took control of Garissa University last month in a dawn attack, taking a...Read complete article© Voice of America - Friday, May 22, 2015


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|Publication number
|Publication type
|Application number
|Publication date
|Feb 4, 2003
|Filing date
|Jul 20, 2000
|Priority date
|Jul 20, 1999
|Fee status
|Also published as
|Publication number
|Martin Moskovits, Konstantin B. Shelimov, Dmitri N. Davydov, Thomas L. Haslett
|Original Assignee
|Martin Moskovits, Konstantin B. Shelimov, Dmitri N. Davydov, Thomas L. Haslett
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (15), Non-Patent Citations (4), Referenced by (47), Classifications (16), Legal Events (3)
|External Links: USPTO, USPTO Assignment, Espacenet
This patent application relates to United States Provisional Patent Application Ser. No. 60/144,627 filed on Jul. 20, 1999, entitled NEAR-FIELD SCANNING OPTICAL MICROSCOPE WITH HIGH Q-FACTOR PIEZOELECTRIC SENSING ELEMENT.
The present invention relates to near-field scanning optical microscopes using high Q-factor piezoelectric sensing elements.
Near-field scanning optical microscopy is capable of producing optical images with resolutions surpassing the half-wavelength limit of conventional far-field microscopy. The probe of a near-field scanning optical microscope (NSOM) is a small aperture, usually the tip of a sharpened optical fiber, scanned in close proximity to the sample's surface. The aperture serves as either a light-source illuminating the sample, or as an aperture collecting light emitted or scattered from the sample. In order to achieve subwavelength resolution, the aperture-sample distance must be scrupulously controlled by an appropriate feed-back strategy. Height control is most frequently accomplished optically; that is, the fiber tip is caused to vibrate at one of its resonant frequencies. A laser beam is focussed onto the fiber, and the height-dependent transverse vibrational amplitude of the tip is measured using, for example, a photodiode. 1 The amplitude is then used as the feedback parameter used to maintain the tip at approximately a fixed distance above the surface. An alternative control scheme, introduced recently by Karrai and Grober2, utilizes a quartz micro-tuning fork as the height-sensing element. As the tip of the optical fiber (which is attached to the tuning fork) approaches the sample surface, the amplitude, phase and frequency of the tuning fork's vibrational normal modes change. Any one of these parameters can then be used as the feedback signal for tip-sample distance control. In the design of ref. 2 the tuning fork was used strictly as a sensing element; an additional piezo element was used to dither the optical fiber/tuning fork assembly parallel to the sample surface. Another strategy, introduced by Atia and Davis3, makes use of the tuning fork as both the dithering and the sensing element. Piezoelectric tip-sample distance regulation yields a number of advantages over optical control including simplicity, compactness, less drift in the feedback loop and lower levels of parasitic optical background.
Since the original publication, a number of NSOMs utilizing piezoelectric height control have been described.4,5,6,7,8,9,10 Most operate in the so-called "shear-force mode". In this configuration, an optical fiber is attached along the edge of one of the tuning fork's tines, and the tuning fork is oriented such that the tip vibrates parallel to the sample surface. In an alternative orientation the fiber tip vibrates approximately along the normal to the sample surface but without making contact with the sample surface. (We will refer to this mode of tip motion as a perpendicular mode of operation.) In this mode of operation the tip senses higher force gradients resulting in more reliable tip-sample distance control. To the best of our knowledge, only two NSOM instruments with piezoelectric sensing elements in which the tip vibrates along the normal to the surface have been described so far. Muramatsu et al.7 describes an instrument in which the perpendicular mode of operation is achieved by bending the tip of the optical fiber glued along the edge of a tine by approximately 90�. Tsai and Lu10 attached an optical fiber across a tine and used a piezoelectric bimorph to dither the tuning fork/fiber assembly normal to the sample surface. However, the quality factors of the tuning fork/optical fiber assemblies described by both groups were substantially lower than the Q-factors normally reported for shear force instruments. Hence, the perpendicular mode of operation in both of these instruments was achieved at a cost in the overall instrumental performance from those achieved in the shear mode configuration. In addition, bending the optical fiber in [7] potentially results in optical losses.
The magnitude of the Q-factor of the tuning fork/optical fiber assembly is a central factor influencing the performance of a near-field microscope with piezoelectric sensing elements. Commercially available quartz micro tuning forks have very high Q-factors, ranging from 50,000 to 200,000 in vacuum and 10,000 to 20,000 in air. Attaching an optical fiber to one of the tines of a tuning fork causes a large reduction in Q-factor. For NSOMs operating in the shear force mode, Q-factors of 1,000 to 3,000 have been reported. By contrast the Q-factors of instruments operating in the perpendicular mode described in the literature so far did not exceed several hundred. The minimum force (or force gradient) detectable by an instrument is proportional to Q−�; hence a large Q is crucial if high sensitivity increase is to be achieved.11 Hence, in the instruments described so far, the potential gain in instrument sensitivity normally achieved by operating the NSOM in the perpendicular mode was significantly offset by their lower Q-factors. Moreover, because stable self-sustained oscillations are difficult to achieve with low-Q-factor piezoelements, additional dithering elements had to be used to cause the tuning fork/optical fiber system to vibrate thereby complicating the device and introducing an additional source of drift in the feedback signal.
It is an object of the present invention to provide a optical fiber/tuning fork sensor assembly for use in a near field optical microscope having a Q-factor superior to currently available sensor assemblies
In one aspect of the invention there is provided a piezoelectric sensing element for use in a near-field scanning optical microscope, comprising:
a micro tuning fork mounted in a holder, the micro tuning fork including first and second tines and the holder having a piezoelectric element for dithering the micro tuning fork; and
an optical fiber being connectable to a photodetection means and having a thinned end portion having a diameter less than a threshold thickness, the thinned portion of the optical fiber being attached to said first tine with said first tine being adapted to be adjacent to a surface being scanned in operation.
In another aspect of the invention there is provided a piezoelectric sensing element for use in a near-field scanning optical microscope, comprising:
a micro tuning fork mounted in a holder, the micro tuning fork including first and second tines and the holder having a piezoelectric element for dithering the micro tuning fork; and
an optical fiber being connectable to a photodetection means and a thinned end portion having a diameter less than a threshold thickness, the thinned portion of the optical fiber being attached at a first position thereof to the holder and being attached at a second position thereof spaced from an end of the optical fiber to a first tine at a position spaced from an end of the first tine, the optical fiber extending transversly across the tines of the micro tuning fork, said first tine being adapted to be adjacent to a surface being scanned in operation.
In another aspect of the invention there is provided a A piezoelectric sensing element for use in a near-field scanning optical microscope, comprising:
a micro tuning fork mounted in a holder for operation in a shear mode, the micro tuning fork including a pair of tines and the holder having a piezoelectric element attachable thereto for dithering the micro tuning fork; and
an optical fiber having an end portion connectable to a photodetection means and a thinned end portion having a diameter in a range of about 40-80 μm, the thinned portion of the optical fiber being attached along a length of one of said tines.
The present invention will now be described, by way of example only, reference being had to the accompanying drawings, in which:
FIG. 1. A detailed view of a micro tuning fork, tuning fork holder and a thinned optical fiber assembled in accordance with the present invention.
FIG. 2. The inverse Q-factor of a mass-loaded quartz tuning fork plotted as a function of the mismatch between the resonance frequencies of the fork's tines. The tip of one of the tines was loaded with a drop of polymethylmethacrylate of a varied size (from an acetone solution). The tine frequency mismatch is assumed to be twice the shift of the resonance frequency of the fork upon loading. The line is the fit to the data of the form 1/Q=1/Q0+αΔf2, where α is an adjustable parameter.
FIG. 3. Schematic of the mode of attachment of an optical fiber to a tuning fork for operation in the perpendicular mode. Points A and B correspond to the respective points in FIG. 1. The transverse displacement of point B relative to point A, y0, is the sum of the displacements in and out of the plane of the fork. The vertical displacement, x0, of point A is due to the vibration of the tuning fork.
FIG. 4. The Q-factor (squares) and the tine frequency mismatch Δf(circles) of a tuning fork/optical fiber assembly measured as a function of the diameter of the thinned portion of the fiber. The tine frequency mismatch is assumed to be twice the shift of the resonance frequency of the fork upon loading. For a fiber diameter of 80 μm, the Q-factor is very small even though Δf is lower than for fibers of smaller diameter. This is due to the decoupling of the vibrations of the two tines of the fork under the extreme loading of one of the tines.
FIG. 5. The Q-factor of a tuning fork loaded with a 50 μm diameter tungsten tip as a function of the tip length.
FIG. 6. A schematic diagram summarizing the range of tip size parameters resulting in optimal and nonoptimal operation of the tuning fork tip assembly. Here d is the diameter of the tip, L is its length, and λ is the wavelength of sound at the tuning fork frequency propagating in the medium of which the tip is comprised.
FIG. 7. The Q-factor of a tuning fork/optical fiber assembly measured as a function of the diameter of the thinned portion of the fiber. The degree of bending of the fiber was maintained approximately constant for all measurements. The solid line is a guide to the eye.
FIG. 8. A schematic diagram of the near field scanning optical microscope.
FIG. 9. Topographic (a) and optical (b) images of a closed-packed two-dimensional array of fluorescent 477 nm diameter polystyrene beads. The far field image of the sample obtained with an inverted microscope is shown in (c).
FIG. 10a to FIG. 10c. Fiber tip preparation procedure is shown.
FIG. 11. Optical microscope and SEM images of the fiber tip prepared as illustrated in FIGS. 10a to 10 c.
FIG. 12. Optical throughput as a function of the metal film thickness of the fiber tip prepared as illustrated in FIGS. 10a to 10 c.
FIG. 13. Cross-sections taken from the upper left corner to the lower right corners of topographic and optical images taken with the fiber tip prepared according to FIGS. 10a to 10 c.
FIG. 14. A detailed view of the thinned optical fiber assembled with a micro tuning fork to be used as a sensing element for an NSOM in the shear force mode.
In the present application the inventors present a theoretical analysis of the dynamics of an optical fiber/tuning fork assembly together with experimental verification of these results. The goal is to analyze the principal causes of the Q-factor deterioration and suggest possible ways to overcome them. The present analysis is primarily applicable to the perpendicular mode configuration, where the problem of low Q-factors has proved to be particularly serious. The impact on the Q-factor of such parameters as the diameter of the optical fiber, the degree of its bending, the location of its points of attachment to the tuning fork, and the transverse vibrational normal modes of the fiber tip, which depend on its length were considered. Based on the results of the analysis, the inventors have been able to provide a perpendicular mode NSOM with Q-factors of the optical fiber/tuning fork assembly up to 9,000, far exceeding those reported in the literature so far.12
Commercially available quartz micro tuning fork crystals (Raltron, R38) with resonance frequency of 32,768 Hz and Q-factors of ˜15,000 in air were used in the present studies. The dimensions of the tuning fork tines were 3.5�0.6�0.25 mm. Optical fibers (Newport Corp., F-SV) were used with 4 μm core, and 125 μm cladding diameter. The cladding diameter can be reduced substantially by etching in 49% hydrofluoric acid at room temperature without degrading the optical guiding properties of the fiber. In a typical fiber preparation procedure, the cladding of an optical fiber was etched down to about 60 μm over a length of approximately 1 cm. A sharp tip was then formed by drawing the fiber while heating its thinned portion in the plasma discharge of a commercial fiber splicer. A protective layer of polymethylmethacrylate was deposited on the fiber tip (out of an acetone solution). The thinned portion of the fiber was then further etched down to the desired diameter (usually 17-25 μm). The protective layer was then removed with acetone. Optionally, the fiber tip could be sharpened by further etching in 49% hydrofluoric acid for approximately 30 seconds.
In order to operate the NSOM in the perpendicular mode configuration (the configuration in which the fiber tip vibrates approximately along the normal to the sample surface as it scans), the tuning forks were mounted in a specially designed titanium holder shown generally at 10 in FIG. 1. A quartz tuning fork/optical fiber assembly used for the Q-factor measurements in the perpendicular mode configuration includes tuning fork 22 having tines 24 mounted in holder 26. The end section 28 of an optical fiber 30 was reduced by etching to about 20 μm. The assembly is mounted in the specially designed titanium holder 26. The fiber 28 is attached to one of the tines 24 of the fork 22 at point A and to the holder 26 at points B and C. This attachment isolates the portion of the fiber 28 below point B from the rest of the fiber, so that only this portion of the fiber influences the dynamical properties of the assembly.
Fibers were epoxy-glued to the lower tine of the tuning fork after it was mounted in its holder (point A in FIGS. 1 and 3) and, to two locations on tuning fork holder (points B and C). The distance between points A and B is approximately 3 μm. The dynamical properties of the tuning fork/optical fiber assembly are determined only by the portion of the fiber 28 below the point of attachment to the holder (point B in FIGS. 1 and 3). The rest of the fiber 30 can be made as long as desired with no noticeable effect on the Q-factor of the assembly. In assessing the operation of these assemblies in the shear-force configuration, un-etched 125 μm fibers wee glued along the edge of one of the tines of the fork. Likewise, we investigated the behavior of the tuning-fork sensors when loaded with a thin element with a density and elastic properties very different from those of quad. For example, tips were made from a 50 μm diameter tungsten wire of a varying length. Of course, under such circumstances the assembly would used as an AFM rather than as an NSOM.
Our ultimate goal was to adapt the NSOM design described by Atia and Davis3 to a perpendicular mode configuration. In this configuration, the tuning fork which serves as the frequency-determining element of the circuit is connected in a positive feedback loop. The resonance frequency of the tuning fork/optical fiber assembly changes as the fiber tip approaches the sample surface. The frequency change is tracked with a phase detector13, and the signal from the phase detector is fed to the electronics controlling the position of the tuning fork above the sample surface through a z-piezo. The scanning of the fiber tip at a fixed height above the sample surface is achieved by forming a phase-locked loop, with the tuning fork being the frequency-setting element and the z-piezo electronics serving as a voltage-controlled oscillator. In order to achieve stability the piezo element must have a sufficiently narrow bandwidth. A bandwidth of 15 Hz or lower, corresponding to a Q-factor of 2000 or higher is found to confer sufficient stability to our assemblies. Ideally, one should attempt is to acheive conditions corresponding to even higher Q-factors for even greater stability.
I. The Effect of Tine Asymmetry on the Q-factor
The high Q-factor of a tuning-fork resonator is critically dependent on the symmetry and equivalence of the tines. For strictly equivalent tines the principal antisymmetric vibrational mode of the fork does not involve any motion of the tuning-fork's base in the direction parallel to the tines' motion, minimizing, thereby, the energy dissipation due to vibrational excitation of the base. Changing the mass or stiffness of one of the tines in comparison with the other due, for example, to the attachment of an NSOM or AFM probe, breaks the symmetry, thereby exciting base motion. This is one of the main causes of Q-factor deterioration. The degree of asymmetry can be characterized by the mismatch, Δf, between the resonance frequencies of the fork's tines. FIG. 2 shows the dependence of the Q-factor on Δf for a tuning fork with one of the tines loaded with a droplet of polymethylmethacrylate of varying mass. Δf was defined as twice the shift of the resonance frequency of the fork upon loading. (This is strictly true only if the shape of the resonance curve is unchanged upon loading and the coupling between the tines is symmetric.) Q is found to depend on Δf approximately as:
where Q0 is the Q-factor of the unperturbed tuning fork. The quadratic dependence of Q on Δf is expected when the main energy dissipation mechanism is the induced motion of the fork's base.14 However, a quadratic dependence was also observed for many other types of tuning fork perturbations. Accordingly, the approach we take below is to consider the dynamical properties of a loaded tuning fork almost entirely in terms of the frequency mismatch between its tines whatever the source of Q-factor decrease. Deviations from eq. (1) can arise, however, if such energy loss channels as dissipation in the tines themselves, in the optical fiber or the fiber tip, or in fork/fiber contacts are competitive with dissipations due to vibration of the base. (In principle, even if the tines are loaded symmetrically so that Δf=0, Q-factor degradation can still occur due to an increase in the amplitude of base vibrations in the direction perpendicular to the motion of the tines, since tines are so designed as to minimize such vibrations in the unloaded fork.) However, if Δf≠0, this source of Q-factor degradation is, relatively, less important.
The change in the resonance frequency of a tuning fork's tine upon attaching an optical fiber is due both to the additional mass and the additional stiffness imparted to the tine by the fiber. Thus:
Here ΔK and ΔM are the changes in the effective force constant and the effective mass of the fiber which are assumed to be small. K and M are the effective force constant and mass of one of the tuning fork's tines. In the thin cantilever approximation, K=βn 4EI/L3, where E is Young's modulus of the tine's material, I is the cross-sectional moment of inertia of the tine, L is its length, and βn is an eigenvalue corresponding to the nth vibrational mode of the cantilever (e.g. β1=1.875).
II. The Shear-force Configuration
In the shear force mode, a fiber is normally glued along the edge of a tuning fork's tine. Hence, the deformation of the fiber can be viewed as pure bending, and ΔK≈βn 4EfIf/L3, where Ef is Young's modulus for the fiber material, and If is the cross-sectional moment of inertia of the fiber given by If=0.25w2S, where w is the width of the tuning fork's tine and S is the fiber cross-section. Taking into account that for a rectangular tine of width w and height h, I={fraction (1/12)} w3h, ΔK/K=3EfS/Ewh≈3ΔM/M if one assumes the Young's moduli of the quartz tuning fork and the optical fiber to be approximately equal. Therefore, both the mass and the stiffness contributions to the tine frequency mismatch are of the same order of magnitude. The frequency mismatch of the two tines of the tuning fork is Δf/f≈ΔM/M=24 for a 125 μm diameter optical fiber and the tuning forks used in our experiments. For a tuning fork with a resonance frequency of 32,768 Hz, the frequency shift is ≈700 Hz. Q-factors in the range 1000-1700 have been reported for frequency shifts of this magnitude.2,9 Thus in the shear-force configuration small frequency shifts (Δf/f<<1) and moderately large Q-factors can be obtained without any special modification of the optical fibers. As we demonstrate in the next section, this is not the case in the perpendicular mode.
III. The Perpendicular Mode Configuration
In the perpendicular mode, the fiber must ideally be oriented across the tines of the tuning fork and attached to one of the tines. (Alternatively, the fiber can be attached along a tine and the fiber tip bent. The drawback of that strategy was discussed above.) The fiber also has to be attached to a stationary support in order to decouple the guiding portion of the fiber from the tuning fork. In our design, this is achieved by placing the tuning fork in a holder and epoxy-gluing a portion of the fiber to the holder (see FIG. 1). In the course of attachment, the fiber inevitably sustains some degree of bending. Bending of the fiber can also be introduced deliberately. As we show below, the degree of fiber bending has a profound effect on fiber dynamics and on the magnitude of the Q-factors achieved in the perpendicular mode configuration.
FIG. 3 shows a schematic of the fiber's attachment to the tuning fork and defines the relevant geometrical parameters. The degree of fiber bending is characterized by the displacement y0. This parameter is defined such that it takes into account the fiber bending both in and out of the plane of the tuning fork. Only the limit of small bending deformations of the fiber, i.e. (y0/I)2<<1 will be considered. The deformation energy of the fiber in this limit is given by:15
Here E is Young's modulus of the material of the fiber, S is the fiber cross-section, I is its cross-sectional moment of inertia, and ε(x) is the fiber strain. The first and the second terms represent the energies of longitudinal and bending deformations of the fiber respectively. The longitudinal deformation of the fiber arises from both stretching and bending. i.e. ε(x)=du(x)/dx+�(dy(x)/dx)2, where u(x) is the displacement of the point x of the fiber along the x axis (FIG. 3). Since no stretching force is applied to the fiber when it is attached to the tuning fork, we assume that ε(x)=0. We also assume that at point A the fiber is oriented perpendicular to the tine, as would ideally be the case for operation in a "pure" perpendicular mode. The shape of the fiber can then be found by variationally minimizing V with respect to y, i.e. by solving Euler equation
with boundary conditions y(0)=0, dy/dx(0)=0 and y(I)=y0. The solution of (4) is:
which is the well-known expression for the bending deformation of a thin cantilever beam under a force couple.15
We now consider the deformation of the fiber induced by vibrations of the tuning fork. Such a deformation results in both additional stretching, u1(x), and bending, y1(x), of the fiber, and a total strain: ε(x)=du/dx+du1/dx+�(dy/dx+dy1/dx)2. The total bending deformation equals y+y1. As a first approximation, one can assume that the vibration of the tine results in a displacement such that point A moves strictly along x, and negligibly along y. The boundary conditions at the lower end of the fiber when point A is at x0, are: u1(0)=x0, y1(x0)=−y(x0), and dy1/dx(x0)=dy/dx(x0). The latter two conditions ensure that the lower end of the fiber remains on the x axis. Point B, remains stationary as the tuning fork vibrates, so that u1(I)=y1(I)=dy1/dx(I)=0. Taking into account the condition u+�(dy/dx)2=0, and minimizing V with respect to u1 and y1, one obtains the following Euler equations:
Using the six boundary conditions above, these two equations can be easily solved assuming x0<<y0, i.e. y1 small compared to y. The resulting expression for the fiber strain, ε, is:
The right-hand part of Eq. 8 was obtained by explicitly expressing S and I as functions of the fiber diameter d. The resulting expressions for the bending and stretching/compression force constants of the fiber, obtained from Eq. (3), are:
The force constants obtained from Eq. (3) have been multiplied by a factor of 4 in Eq. (9) and (10). This is due to the fact that the effective force constant of a fiber mounted at the end of a tuning fork's tine is 4 times its actual force constant (see Eq. (12) in the next section). It is obvious from these expressions that both the fiber diameter and the degree of bending of the fiber have profound effects on its dynamics. Before etching, the outer fiber diameter is 125 μm and y0≦0.5 mm, hence {fraction (9/175)}(y0/d)2<1, so that ΔK˜Ksc˜Ed2/I, as would be the case for a perfectly straight fiber. Hence K/ΔK˜0.1. Such a high fiber stiffness renders the tuning fork/fiber assembly unusable as a sensing element. In order to lower ΔK and obtain reasonably high Q-factors in the perpendicular mode, one must either increase the bending of the fiber (i.e. increase y0), or decrease its diameter. Since excessive bending can result in optical losses, the second approach is preferred. By decreasing the fiber diameter such that {fraction (9/175)}(y0/d)2>>1, fiber bending, as opposed to longitudinal stretching dominates the force constant ΔK, i.e.:
For example, if the fiber diameter is decreased to 25 μm, f/Δf=2K/ΔK=52 (for I=3 mm and y0=0.5 mm), which should result in a dramatic increase of the Q-factor compared to its value for a fiber with 125 μm outer diameter.
Eq. (11) implies that ΔK and hence the Q-factor should be a very sensitive function of the diameter and the degree of bending of the fiber. The degree of bending is difficult to measure with adequate precision. However, we do observe that for a given fiber diameter the Q-factor can change by a factor of ten as y0 is increased by appmximately 0.1 mm, in qualitative accord with Eq. (11). FIG. 4 shows the experimentaly measured dependence of Δf and the Q-factor of a tuning fork/optical fiber assembly on the diameter of the thinned portion of the fiber. For these measurements, the fiber 30 was prepared as described in the Experimental section and attached at a point near the middle of one of the tines 24 of tuning fork 22 (as in FIG. 1). The degree of banding of the fiber section 28 was maintained approximately constant for the various measurements, to the extent feasible. The Q-factor is very low for thicker fibers, but shows a sharp upturn when the fiber diameter is reduced to ˜25 μm. This abrupt behavior is consistent with the expected d4 dependence of the stiffness of the fiber on its diameter (Eq. 11), which should produce a d8 dependence for Q on d. Because other effects also contribute to the reduction of Q, one does not expect the d8 dependence to be obeyed quantitatively. Qualitatively, however, the measured results conform well with the analysis. For fibers with diameters reduced to 17 μm, we measured Q-factors of approximately 9000, i.e. approaching the Q-factor of the unloaded tuning fork (Q0=15,000). Note that for the thinnest fibers (d=17 μm) Δf is negative, indicating that in this size range the resonance properties of the fork/fiber assembly are already determined by the mass of the epoxy glue rather than by characteristics of the fiber itself.
IV. Influence of the Point of Attachment of the Optical Fiber
In preparing a fiber/tuning fork assembly for use in the perpendicular mode, one can, in principle, attach the fiber at any point along a tuning fork's tine. However, the effective mass AM and effective stiffness ΔK of the fiber depend critically on the point of attachment. The functional form of this dependence ran be obtained quantitatively by considering the vibration of a "double span" cantilever beam with a point mass, m, and a lateral coil spring with a force constant, k, attached at a distance x from the cantilever base. The point mass and the spring represent the effects of the mass and the stiffness of the fiber. A detailed discussion of vibrational problems of this type can be found, for example, in [16]. For k and m small compared to the stiffness and the mass of the cantilever beam, the ratio between the effective and actual mass or stiffness is
Here μ=x/L, where x is the distance from the point of attachment of the fiber to the tine's base and L is the length of the tine, γ=1−μ, and βn are as specified for Eq. (2). For the first vibrational mode of a cantilever (β1=1.875), ΔK/k and ΔM/m scale approximately as μ3. At the same time, the vibrational amplitude of the fiber tip, A, as a function of x can be obtained from the well known expression for free vibrations of a cantilever beam (the same expression also describes forced vibrations induced by a force applied at the end of the beam):
where A0 is the vibrational amplitude of the end of the cantilever. For the first vibrational mode, the amplitude scales approximately as μ1.5. The sensitivity of an instrument is affected both by the Q-factor and the vibrational amplitude of the probe tip. Hence it is the product QA2 that must be maximized in order to optimize the sensitivity.11,13 If the Q-factor scales as Δf2, as suggested by Eq. (1), the gain in the Q-factor resulting from the attachment of the fiber closer to the tuning fork's base outweighs the loss in vibrational amplitude, resulting in an overall increased sensitivity of the assembly. By taking into account Eqs. (1), (12) and (13) one can, in principle, predict the optimal point of attachment of the fiber which maximizes the quantity QA2. However, we could not confirm the predictions of Eq. (12) experimentally. This is due, mainly, to the uncertainty in the degree of bending of the fiber, which is difficult to control precisely, but can have a profound effect on the Q-factor. In our final design of the sensing element for a perpendicular mode NSOM, we simply chose to attach the fiber at the middle of the tuning fork's tine. This results in a several-fold increase of the Q-factor compared to attaching the fiber near the end of the tine.
V. Influence of the Length of the Probe Tip on the Q-Factor
Thus far we have only considered the change in the Q-factor of a loaded tuning fork due to the asymmetry of the tines and vibrational excitation of the fork's base. Other energy loss channels, such as the dissipation in the optical s fiber itself or in the tuning fork/fiber contacts, can also contribute to the degradation of the Q-factor. For example, we found that under certain circumstances the length of the probe tip can have a profound effect on the Q-factor of the assembly on top of the effect of the mass that it adds to the tine. Such tip-length effects were found to be less pronounced for optical fibers used as NSOM probes than for tungsten tips. FIG. 5 shows the Q-factors measured for a tuning fork with a 50 μm tungsten tip attached to one of its tines, as a function of the tip length. Based on the data shown in FIG. 2, one expects the Q-factor to decrease approximately quadratically with the tip length. The tip serves as a mass load, and the frequency mismatch between the fork's tines is expected to be proportional to the mass of the tip (and hence to its length. However, FIG. 5 indicates that the measured Q-factor dependence on tip length is a little more complicated. Superimposed on the quadratic function are three sharp drops in the Q-factor at tip lengths of ˜1, 2.5 and 4.6 mm. The resonance frequencies fn of the nth transverse vibrational mode of a tip of diameter d and length L is given by the well-known expression:
where the speed of sound, c=(E/p)�=4300 m/s for tungsten, β1=1.875, β2=4.694 and β3=7.855. Using this formula together with the known frequency of the tuning fork (33 kHz) and the tip diameter of the tungsten tip (50 μm), one calculates that the first, second and third resonances of tips of length 0.96, 2.4 and 4.0 mm Will have frequencies equal to 33 kHz. i.e. the resonance frequency of the fork. These numbers are in acceptable agreement with the tip lengths at which the Q-factor drops are observed. This suggests that the observed drops in the Q-factor at these tip lengths is due to the energy dissipation arising from the resonance excitation of transverse vibrations in the tip. These decreases in Q-factor can be quite dramatic (FIG. 5), despite the fact that the motions of the tuning fork and the tip are orthogonal to each other and are, therefore, expected to be uncoupled to first order. Other Q-factor losses were also observed. For example, bending the tip away from the direction perpendicular to the tuning fork's tine results in a 20-30% Q-factor decrease, likely due to the increased coupling between the vibrations of the tuning fork and the transverse vibrations of the bent tip.
The observations presented above are generalized in FIG. 6, where we plot the inverse aspect ratio of the tip, d/L, versus the dimensionless tip length, L/λ, where λ=c/f is the wavelength of sound at the vibrational frequency of the tuning fork, propagating in the material of the tip. The straight line in FIG. 6 represents the condition imposed by eq. 14 for n=1. Because the line is plotted in terms of dimensionless variables it is a universal curve for all materials. For tips with d and L falling in the area below the straight line, no Q-factor deterioration due to vibrational excitation of the tip occurs, while in the area above the line such excitations are possible, hence the Q-factor might be degraded for tip parameters above the line. The Q-factor is also affected by the mass of the tip. The data plotted in FIG. 5 imply that the mass of the tip should not exceed 0.15 mg it a Q-factor in excess of 3000 is desired. The two hyperbolic curves in FIG. 6 represent this condition for tungsten and quartz. The Q-factor of a tuning fork/tip assembly exceeds 3000 if d and L of the tip lie below the corresponding curve. Thus the area in the diagram labeled "High Q-factor, no tip excitation" defines the desirable tip parameter range for high-Q operation. For tips with dimensions falling outside this area, the Q-factor is expected to be lower, either due to too large a tip mass, or non-optimal tip resonance conditions. The preferred tip size area for quartz is larger than for tungsten, due to its lower density and the higher speed of sound in quartz.
Causes for the deterioration of the Q-factor of NSOMs or AFMs using piezoelectric tuning forks as height control elements were analyzed and discussed, For NSOMs used in the "shear-force" mode of operation, the attachment of the optical fiber to the fork only moderately perturbs the force constant of the tuning fork's tine, because of the fiber's relatively low bending stiffness. Thus, even optical fiber tips with 125 μm outer diameters will not greatly reduce the Q-factor of piezoelectric tuning forks used in this fashion.
Contrariwise, for an NSOM based on a tuning-fork sensor configured in the perpendicular mode, the high stretching stiffness of the fiber results in a dramatic increase in the tine's force constant and a consequent dramatic lowering of the fork's Q-factor, in order to overcome this problem and achieve a reasonably high (>2000) Q-factor, one must reduce the outer diameter of the fiber below 25 μm. The fiber must also be slightly bent. These two modifications cause the vibrational dynamics of the resulting assembly to be dominated by the fiber's bending stiffness which, according to our analysis, is expected to depend on the fiber diameter, d, as d4. A steep upturn was observed in the Q-factor of the tuning fork/optical fiber assembly as the fiber diameter was reduced below 25 μm, in accord with this prediction. Further substantial improvements in the Q-factor is achieved by attaching the fiber approximately midway between the fork's base and the tip of a tine. Such a strategy is expected to improve both the Q-factor and the force sensitivity of the microscope. (The latter depends both on the Q-factor and the vibrational amplitude of the probe tip.) Additionally, we determined that resonantly excited transverse tip vibrations also result in a significant Q-factor deterioration for certain tip lengths. Combining all of these insights we define the optimal parameter range for probe tips used either as NSOMs or AFMs using micro tuning forks as height sensing and regulating devices. By taking these insights into account we have successfully designed and built tuning fork/optical fiber assemblies with Q-factors up to 9000, and incorporated them into a perpendicular mode NSOM which utilizes the tuning fork both as the dithering and the sensing element.12
In accordance with the above discussion, the following steps were used to prepare a tuning fork/optical fiber assembly. First, the cladding of a 125 μM optical fiber (Newport Corp., F-SV, core diameter4 μm) is etched in 50% hydrofluoric acid to a diameter ˜60 μm over a length ˜1 cm. A sharp tip is then made by drawing the fiber while heating it in the plasma discharge of a commercial fiber splicer. The tip is covered with a protective layer of polymethylmethacrylate, and the fiber cladding is further etched down to 17-25 μm. The two-step etching sequence is necessary because 25 μm fibers are too thin to be conveniently handled using a fiber splicer. The protective layer on the fiber tip is then removed by dissolution in acetone. The fiber is epoxy-glued to a tine of a tuning fork near its middle. The other end of the thinned portion of the fiber is glued to the tuning fork holder (FIG. 1) specially designed with this configuration in mind. The measured Q-factors of a tuning fork/optical fiber assembly prepared in this way are shown in FIG. 7, as a function of the diameter of the thinned portion of the fiber. The Q-factors show a sharp upturn near a diameter of 25 μm. This abrupt behavior is qualitatively consistent with the sharp dependence of the stiffness of the fiber on diameter (Eq. 4). For fibers with diameters ˜17 μm, the Q-factors were ˜9000, approaching the Q-factor of an unloaded tuning fork (Q0=15,000). Also, Δf is negative, indicating that for such thin fibers the resonant properties of the fork are primarily determined by the is mass of the epoxy glue rather than by the elastic properties of the fiber.
A schematic diagram of a perpendicular mode near-field scanning optical microscope 50 employing the tuning-fork/optical fiber assembly described above is shown in FIG. 8. The holder 26 holding tuning fork 24 with fiber 30 attached thereto is glued to a piezoelectric scanning tube 52, which is, in turn, coaxially mounted in an inchworm linear motor 54 mounted in a support housing 56 used for coarse approach of the fiber tip 28 to the sample surface. The tuning fork 22, vibrating at its resonant frequency, acts as the frequency-setting element in a positive feedback loop. The variation of any of the three vibrational parameters of the tuning fork: amplitude, phase or frequency can, in principle, be used to control the tip-sample distance. We chose to use the change in frequency, as it allows for faster response times, which is especially important for systems with high Q-factors.17 The signal from the tuning fork 22 is passed through a tunable two-pole LC-filter 58, which introduces a frequency-dependent phase shift, and through an analogue multiplier 60. The resulting signal, which is proportional to the change in the tuning fork's resonant frequency as the tip approaches the sample, is used as a feedback signal for regulating the tip-sample distance. The sensing element disclosed herein advantageously provides a vertical resolution of 1.5 Å for a tuning fork/optical fiber assembly with a Q-factor of 9,000.
The NSOM is operated in a photon scanning tunneling microscope (PSTM) mode. The sample is deposited on a piece of a Pyrex slide and then mounted on the surface of an attenuated total internal reflection prism using an index-matching fluid. An optical fiber/lens assembly 64 mounted on the sample stage is used to couple a laser beam into the ATR prism 66. The sample is excited by the evanescent field of the totally internally reflected light. The light emitted or scattered by the sample is collected by the sharpened optical fiber section 28 attached to the tuning fork 22 and detected with a photomultiplier 70 either directly or after passing through a spectrophotometer (not shown). The sample stage and the tuning fork assembly are mounted on top of an inverted microscope 74, allowing the far field image of the sample to be simultaneously collected.
Typical topographic (AFM) and near- and far-field optical images of the surface of a trial sample are shown in FIG. 9. The sample consists of a closed-packed array of 477 nm polystyrene spheres doped with a fluorescent dye (Fluoresbrite, Polysciences Inc.). The fluorescence, which is excited with 514.5 nm light from an Ar-ion laser, is filtered using a long-pass filter with a 530 nm cutoff. Excellent resolution is obtained in the AFM image, both horizontally and vertically, allowing a clear imaging of interstices between spheres. In the optical image, the lateral resolution is not that good. This is due to the fact that the fiber tip was not metal-coated, hence the optical signal originates from several adjacent spheres.
Studies were carried out to determine the optical and mechanical properties and in particular the optical throughput of chemically thinned, metal-coated fiber tips used as Near Field Scanning Optical Microscopy (NSOM) probes. This approach has the two major advantages of allowing the NSOM tip to be dithered perpendicular to the sample surface while preserving the high quality factor of the tuning fork, The latter is very important to preserving a high NSOM sensitivity and signal-to-noise ratio. Incorporating the tuning fork in the Phase-Locked Loop circuit fully compensates for the scanning speed losses related to the high quality factors.
Fiber tips were prepared by removing the plastic coating over a length of approximately 8 cm (3″) from one end of the fiber (FIG. 10a) and etching the uncovered part in a 48% HF solution for 20 minutes (FIG. 10b). This process decreased the diameter of the fiber to ˜60 μm. After etching, the fiber was placed in a commercial fusion splicer and a sharp tip was formed by applying a number of short arc-discharge pulses. The tip was then immersed into a drop of clear nail polish (this is essentially a solution of polymethylmethacrylate in acetone) to an approximate depth of 0.5 mm in order to protect the tip against additional etching by HF. The nail polish was allowed to dry for approximately 15 minutes and the fiber was again immersed into HF and etched for 14 minutes, reducing its thickness down to ˜25 μm (FIG. 10c). The fiber was carefully washed in distilled water and acetone, sequentially, in order to completely remove residual HF and the nail polish from the tip. The sharpness of the tip was checked by high-resolution optical microscopy and placed into the metal-vapor deposition chamber.
A mechanical feedthrough allowed the fiber end to be rotated during metal deposition ensuring uniformity of metal coverage. The fiber end was oriented at an angle of ˜45 degrees with respect to the metal vapor source during the metal-film deposition in order to minimize metal deposition on the very end of the tapered fiber tip. FIG. 11 shows an optical microscope image of the tip after depositing ˜1 μm silver on the fiber.
VI Optical Throughput Measurements
Two types of fiber tip constructions were used for the optical throughput measurements, the first (standard tip) was prepared by sharpening an un-thinned fiber with a diameter of 125 μm; the second (thinned tip) was a fiber first thinned to a diameter of ˜25 μm using the procedure described above before sharpening. The optical throughput of the two fiber bps was measured by coupling a He—Ne laser beam to the unsharpened end of the fiber and measuring power of the output optical signal detected at the sharpened end of the fiber. FIG. 12 shows comparative results for the optical throughput as a function of metal-film thickness deposited on surface of the sharpened end of the tip. The measurements presented in FIG. 12 indicate that fiber thinning does not affect the optical throughput significantly.
NSOM and topographic images were acquired as follows. The etched and metal-coated fiber tip was glued to the tuning fork and topographic and near-field optical measurements carried out. Chopped laser light was coupled into a second fiber and focused to ˜100 μm diameter spot on the sample under the tip. The power output of the illuminating fiber was in the range of 3-8 mW. A photomultiplier was used to measure the optical signal collected by the fiber tip. Tip-sample separation was controlled by incorporating the tuning fork in the Phase Lock Loop (PLL) of the electronics. The quality factor of the fork with attached optical fiber was measured to lie in the range of 3000-5000 both for the metalized and un-metalized fiber tips. This ensured very good sensitivity and a high signal-to-noise ratio. Representative experimental results were obtained for a replica optical grating. The cross-sections taken from the upper left corner to the lower right corners of topographic and optical images are shown in FIG. 13. The metal thickness used was 1 μm. The images were obtained with a tuning fork height-sensing feed-back operation and the fiber tip aligned so that it oscillates perpendicularly to the surface being imaged.
The results clearly demonstrate thinning a portion of the optical fiber near the sharpened fiber tips down to a diameter ˜25 μm produces NSOM tips of high resonance quality even when used in a perpendicular vibratory fashion to obtain topographic images. High sensitivity and signal-to-noise is thereby achieved when using a tuning-fork element in the phase-lock loop. Thinning the fiber in the above-mentioned fashion does not significantly affect the optical throughput of the overall fiber probe. Metalizing the tip with silver to a thickness of ˜1 μm does not reduce the Q-factor and hence the quality of operation as both a topographic imaging instrument and an NSOM imaging device.
Thinned and coated fiber tips can also be used in a shear-force mode of operation (i.e. with the tip oscillating tangentially to the surface being imaged) by gluing the fiber along (as opposed to across) one of the tines of the fork. When operated in this manner the fiber need only be thinned to ˜50 μm for high quality factors i.e. Q˜2000-2500 to be achieved. Quality factors of this magnitude are high enough to ensure stable PLL operation.
In summary, the present invention provides a perpendicular mode NSOM, which uses a quartz micro tuning fork as a height sensing element. High Q-factors of the tuning fork/optical fiber assembly are achieved by chemically etching the fiber to final diameters in the range of 17-25 μm. A sharp upturn in the Q-factor is observed when the fiber diameter, d, drops below 25 μm, in accord with the predicted d4 dependence of the stiffness of a slightly bent fiber on diameter. The high Q-factors result in improved force sensitivity and allow to construct a perpendicular mode instrument without the use of additional dithering piezoelements.
In order to further increase the Q-factor and improve sensitivity and stability, the position of the tuning fork was raised approximately 0.1 mm in its mount after the thinned fiber was glued both to the holder (the mount) and to one fine of the fork. This procedure produced a slight arc in the portion of the fiber situated between the two glue points thereby releasing slightly the fiber tension and introducing additional fiber bending, shown in broken lines in FIG. 1, dramatically increasing the Q-factor from the range 1500-2000 to the range 5000-7000.
Thinning the fiber diameter by etching down to 50.60 μm also improves NSOM performance even when the NSOM is operated in the shear force mode as shown in FIG. 14. Hence this claim (thinning the fiber below a critical diameter) is not restricted to NSOMs operated in the perpendicular mode. Typical Q-factor values for unetched 125 μm fiber are in the range 500-1000. Etching the fiber down to 50-60 μm was very surprisingly found to increase the Q-factor to values as high as 3000, which increases the sensitivity of the shear force distance control when phase-locked feedback loop (PLL) is used.
The foregoing description of the preferred embodiments of the invention has been presented to illustrate the principles of the invention and not to limit the invention to the particular embodiment illustrated. It is intended that the scope of the invention be defined by all of the embodiments encompassed within the following claims and their equivalents.
1 E. Betzig, P. L. Finn, and J. S. Weiner, Appl. Phys. Lett., 60, 2484 1992).
2 K. Karrai and R. D. Grober, Appl. Phys. Lett., 68, 1842 (1995).
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6 A. G. T. Ruiter, J. A. Veerman, K. O. van der Werf, and N. F. van Hulst Appl. Phys. Lett., 71, 28 (1997).
7 H. Muramatsu, N. Yamamoto, T. Umemoto, K. Homma, N. Chiba, and M. Fujihira, Jpn. J. Appl. Phys. 1, 36, 5753 (1997).
8 J. Salvi, P. Chevassus, A. Mouflard, S. Davy, M. Spajer, D. Courjon, K. Hjort, and L. Rosengren, Rev. Sci. Instrum., 69, 1744 (1998).
9 A. G. T. Rulter, K. O. van der Werf, J. A. Veerman, M, F. Garcia-Parajo, W. H. L. Rensen, and N. F. van Hulst, Ultramicroscopy, 71, 149 (1998).
10 D. P. Tsai and Y. Y. Lu, Appl. Phys. Lett., 73, 2724 (1998).
11 Y. Martin, C. C. Williams, and H. K. Wickramashinghe, J. Appl. Phys., 61, 4723 (1987).
12 D. N. Davydov. K. B. Shelimov, T. L. Haslett, and M. Moskovits, Appl. Phys. Lett., submitted.
13 T. R. Albrecht, P. Gruftter, D. Home, and D. Rugar, J. Appl. Phys., 69, 668 (1991).
14 Y. Tomikawa, K. Sato, M. Konno, and R. A. Johnson, IEEE Trans. Sonics Ultrason., SU-27, 253 (1980).
15 See, for example, S. P. Timoshenko and J. N. Goodier, "Theory of Elasticity", McGraw-Hill, NY, 1970.
16 D. J. Gorman. "Free vibration analysis of beams and shafts", John Wiley & Sons, NY, 1975.
17T. R. Albrecht, P. Gr�tter, D. Home, and D. Rugar, J. Appl. Phys., 69, 668 (1991).
|Cited Patent
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|Method of making fiber probe devices using patterned reactive ion etching
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|Fiber optic probe for near field optical microscopy
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|Tapping atomic force microscope with phase or frequency detection
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|Dr. Khaled Karrai Und Dr. Miles Haines Gesellschaft Burgerlichen Rechts
|Coupled oscillator scanning imager
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|High resolution fiber optic probe for near field optical microscopy and method of making same
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|Nanometer distance regulation using electromechanical power dissipation
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|Scanning near-field optical microscope
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|Scanning type near field interatomic force microscope
|Apr 3, 1997
|Oct 15, 1997
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|Muramatsu et al.: "A Self-Sensitive Probe Composed of a Piezoelectric Tuning Fork and a Bent Optical Fiber Tip for Scanning Near-field Optical/Atomic Force Microscopy", Applied Physics Letters, vol. 36, Pt. 1, No. 9A, pp. 5753-5758 (1997).
|Pangaribuan et al.: "Highly Controllable Fabrication of Fiber Probe for Photon Scanning Tunneling Microscope", Scanning, vol. 16, pp. 362-367 (1994).
|Pangaribuan et al.: "Reproducible Fabrication Technique of Nanometric Tip Diameter Fiber Probe for Photon Scanning Tunneling Microscope", Applied Physics Letters, vol. 31, Pt. 2, No. 9A, pp. 1302-1304 (1992).
|Tsai et al.: "Tapping-mode Tuning Fork Force Sensing for Near-field Scanning Optical Microscopy", Applied Physics Letters, vol. 73, No. 19, p. 2724 (1998).
|Citing Patent
|Filing date
|Publication date
|Mar 2, 2005
|Oct 25, 2005
|University Of Washington
|Optical beam scanning system for compact image display or image acquisition
|Apr 15, 2002
|May 30, 2006
|Institut De Microtechnique De L'universite De Neuchatel
|Actuating and sensing device for scanning probe microscopes
|Jan 23, 2004
|Jun 27, 2006
|University Of Washington
|Optical beam scanning system for compact image display or image acquisition
|Feb 25, 2005
|Jul 31, 2007
|Osaka University
|Probe device
|Aug 24, 2006
|Sep 15, 2009
|The Trustees Of Boston College
|Apparatus and methods for manipulating light using nanoscale cometal structures
|Aug 24, 2006
|Nov 24, 2009
|The Trustees Of Boston College
|Nanoscale optical microscope
|Aug 24, 2006
|Dec 15, 2009
|The Trustees Of Boston College
|Apparatus and methods for nanolithography using nanoscale optics
|Aug 24, 2006
|Jan 19, 2010
|The Trustees Of Boston College
|Apparatus and methods for optical switching using nanoscale optics
|Apr 10, 2006
|Jul 13, 2010
|The Trustees Of Boston College
|Apparatus and methods for solar energy conversion using nanocoax structures
|Aug 24, 2006
|May 17, 2011
|The Trustees Of Boston College
|Apparatus and methods for solar energy conversion using nanoscale cometal structures
|May 2, 2008
|May 31, 2011
|University Of Washington
|High resolution optical coherence tomography based imaging for intraluminal and interstitial use implemented with a reduced form factor
|Jan 27, 2006
|Feb 26, 2013
|University Of Washington
|Catheterscope 3D guidance and interface system
|May 1, 2009
|Mar 12, 2013
|University Of Washington
|Integrated optical scanning image acquisition and display
|Apr 22, 2011
|Apr 30, 2013
|The Trustees Of Boston College
|Apparatus and methods for solar energy conversion using nanoscale cometal structures
|Nov 23, 2005
|Sep 17, 2013
|University Of Washington
|Scanning beam with variable sequential framing using interrupted scanning resonance
|Apr 2, 2007
|Sep 23, 2014
|University Of Washington
|Catheter with imaging capability acts as guidewire for cannula tools
|Sep 7, 2007
|Oct 20, 2015
|University Of Washington
|Monitoring disposition of tethered capsule endoscope in esophagus
|Jan 16, 2013
|Jan 5, 2016
|University Of Washington
|Catheterscope 3D guidance and interface system
|Oct 28, 2013
|Aug 16, 2016
|Hitachi, Ltd.
|Scanning probe microscope and sample observation method using same
|Nov 24, 2015
|Jan 31, 2017
|University Of Washington
|Catheterscope 3D guidance and interface system
|Mar 3, 2006
|Feb 7, 2017
|University Of Washington
|Multi-cladding optical fiber scanner
|Jan 23, 2004
|Aug 5, 2004
|Janet Crossman-Bosworth
|Optical beam scanning system for compact image display or image acquisition
|Apr 15, 2002
|Aug 19, 2004
|Terunobu Akiyama
|Actuating and sensing device for scanning probe microscopes
|Feb 25, 2005
|Jun 30, 2005
|Takuya Matsumoto
|Probe device
|Mar 2, 2005
|Aug 11, 2005
|University Of Washington
|Optical beam scanning system for compact image display or image acquisition
|Apr 10, 2006
|Mar 1, 2007
|The Trustees Of Boston College
|Apparatus and methods for solar energy conversion using nanocoax structures
|Aug 24, 2006
|Apr 12, 2007
|The Trustees Of Boston College
|Apparatus and methods for optical switching using nanoscale optics
|Aug 24, 2006
|May 10, 2007
|The Trustees Of Boston College
|Apparatus and methods for nanolithography using nanoscale optics
|Aug 24, 2006
|May 10, 2007
|The Trustees Of Boston College
|Apparatus and methods for manipulating light using nanoscale cometal structures
|Aug 24, 2006
|Jun 21, 2007
|The Trustees Of Boston College
|Apparatus and methods for solar energy conversion using nanoscale cometal structures
|Aug 24, 2006
|Jun 21, 2007
|The Trustees Of Boston College
|Nanoscale optical microscope
|Oct 14, 2005
|Oct 18, 2007
|The Trustees Of Boston College
|Solar cells using arrays of optical rectennas
|Sep 7, 2007
|Dec 27, 2007
|University Of Washington
|Monitoring disposition of tethered capsule endoscope in esophagus
|Aug 21, 2006
|Mar 6, 2008
|University Of Washington
|Optical fiber scope with both non-resonant illumination and resonant collection/imaging for multiple modes of operation
|Feb 4, 2008
|Jun 5, 2008
|University Of Washington
|Flexible endoscope tip bending mechanism using optical fibers as tension members
|Jan 29, 2008
|Jul 31, 2008
|Solasta, Inc.
|Photovoltaic cell and method of making thereof
|Feb 11, 2008
|Aug 28, 2008
|Solasta, Inc.
|Photovoltaic cell with reduced hot-carrier cooling
|Mar 9, 2007
|Sep 11, 2008
|University Of Washington
|Side viewing optical fiber endoscope
|Apr 2, 2007
|Oct 2, 2008
|University Of Washington
|Multifunction cannula tools
|Jan 22, 2008
|Oct 16, 2008
|Mitutoyo Corporation
|Digital displacement measuring instrument
|Jul 2, 2008
|Jan 8, 2009
|Solasta, Inc.
|Distributed coax photovoltaic device
|Mar 3, 2006
|Jan 22, 2009
|University Of Washington
|Multi-cladding optical fiber scanner
|Nov 27, 2007
|May 28, 2009
|University Of Washington
|Adding imaging capability to distal tips of medical tools, catheters, and conduits
|May 1, 2009
|Sep 17, 2009
|University Of Washington
|Integrated optical scanning image acquisition and display
|May 2, 2008
|Dec 31, 2009
|University Of Washington
|High resolution optical coherence tomography based imaging for intraluminal and interstitial use implemented with a reduced form factor
|Oct 28, 2013
|Dec 31, 2015
|Hitachi ,Ltd.
|Scanning probe microscope and sample observation method using same
|Jan 23, 2004
|Apr 14, 2005
|Janet Crossman-Bosworth
|Optical beam scanning system for compact image display or image acquisition
|U.S. Classification
|250/216, 250/234, 73/105, 977/862, 850/30
|International Classification
|Cooperative Classification
|European Classification
|Aug 23, 2006
|Maintenance fee reminder mailed
|Feb 4, 2007
|Lapse for failure to pay maintenance fees
|Apr 3, 2007
|Expired due to failure to pay maintenance fee
Effective date: 20070204


text:
01. Criminal
02. Satisfaction
03. She Just Can't Make Up Her Mind
04. Holdin' On To Love
05. Walk The Wire
06. After The Love Has Gone
07. First And Last
08. Insincere
09. In The Heat Of The Night
10. Baby, Bye Bye
11. Steve Porcaro, Bill Cantos, John Van Tongeren, Keyboard Solo
12. When You Look In My Eyes
13. Roxann
14. Nothin' You Can Do About It
15. Band Intro
16. Turn Your Love Around
17. Pat Mastelotto Drum Solo and Kenji Sano Bass Solo
18. Show Me The Magic
19. Pamela
20. Stranded
Jay Graydon (Guitar, Vocals)
Bill Champlin (Vocals. B3 Organ, Guitar)
Joseph Williams (Vocals, Keyboards)
Kenji Sano (Bass. Vocals)
Sherwood Ball (Guitar, Vocals)
Steve Porcaro (Keyboards)
Bill Cantos (Keyboards, Vocals)
John Van Tongeren (Keyboards)
Pat Mastelotto (Drums)
Tamara Champlin (Backing Vocals)
Janea Chadwick (Backing Vocals)
Amye Williams (Backing Vocals)


text:
So we've come to the end of the five-week sojourn of comedy that I've been weaving tales from... I guess you could call me a Sojourny Weaver. I know, me being that funny right off the bat isn't making it any easier to come to terms with the fact that this is the last tour diary, and I'm sorry. HOWEVA (Stephen A. Smith ™) we've come to the end, and it's time to put a bow on it. So here it is, the inaugural "Ian Karmel was on the road for a little while and had a variety of experiences" awards!
Best show I got to be a part of: This is a toss-up between the "Funny Over Everything" at Bridgetown Comedy Festival, where I got to be part of a show that included Matt Braunger, Doug Benson and my friends Ron Funches, Shane Torres, Jen Allen and Sean Jordan, and the "Sausage Fest" show at the Moontower Comedy Festival show where I got to perform with Joe Mande, Baron Vaughn, Sean Patton, Bill Dwyer, Brent Weinbach, Jackie Kashian and this other guy who's first name I can't remember, but his last name was Dudey, and he soldiered through that like a champion... I'm going to have to hand the "best show" award to the Sausage Fest show, that's just too much talent, but I'm also going to do this...
Show that almost made me cry: It got RILL dusty in the room during the aforementioned Bridgetown "Funny Over Everything" showcase. With the exception of Doug Benson, everyone involved in that show has a deep connection to Portland - a very good night for our comedy scene.
More awards? Yes! After the jump!
Drunkest: Wednesday night at Moontower Comedy Festival. I hosted a show for Hannibal Burress, and then this really funny dude Paul Varghese and I started doing shots of bourbon, and I — thinking my night was over — started getting really hammered. I was that type of drunk where I had all sorts of important opinions about things and affection for shit that I had previously found meaningless, it was really fun. Then the guy running the festival asked me to do a set on something called the "Super Secret Show" where the line-up for the show was to remain a secret, so as to create intrigue! Maybe Aziz Ansari would show up! He didn't, instead it was me, Ian Karmel, so drunk that I thought I could crip walk. So I did the set, it went well, and so I celebrated by getting even more hammered!
Best Comedy Geek Moment: Maria Bamford and I hung out for fifteen incredible minutes in the green room at Cap City Comedy Club in Austin. We managed to have a fulfilling conversation despite the fact that I was singing the Rocky theme in my head as loud as I could.
Worst person I encountered: This rich, middle-aged, blonde woman in Austin who wouldn't shut the fuck up during my entire set. She just kept talking to her two friends and clinking her white-wine filled glass and rolling her eyes — which would be fine if she were in the back, but this fucking monster was in the second row! Fuck her! Give me a heckler, please. I can deal with a heckler, but I honestly talked directly at this woman for 30 seconds before she even noticed I was talking to her... she was five feet away from me! Mugsy Bogues couldn't have taken a nap in the distance that separated us. For ten minutes I tried to get this woman to shut-up. I tried every tactic imaginable — I was mean to her, I was nice to her, I turned the room against her, I accused her of wanting to sleep with me because she has a 19th century Jew fetish and I look like Tevya from Fiddler on the Roof. Eventually, someone kicked her out, which was awesome... especially when I got the whole room to sing "Tradition" as she was escorted out of the club.
Best thing I ate: I had cheese steaks in Philly, BBQ in Austin, breakfast burritos in Austin and Panda Express in the Mall of America... but the best thing I had on the whole trip has to be the Juicy Lucy in Minneapolis, a hamburger with cheese INSIDE of it. WHAT!? HOW? Dark magics, only explanation.
Wrap it up, dude: This trip was amazing, and I want to thank the Portland Mercury for letting me share it with you guys — I probably wouldn't have kept a diary without them. I'm going to continue to catalog my road trips on a Tumblr — I've already got trips to Denver, Reno and LA in the works — and I'll let you know how to get at those when they're available.
I learned many things on this trip — but I think the most important thing I learned is that I can kill crowds all over the country, people everywhere think I'm really funny and good at stand-up, that's awesome and encouraging and really self-serving and egotistical... so why am I bringing it up? Because I'm probably not even the funniest guy in Portland, and if I am, it's a really close race. We are blessed in this town to have vibrant music, arts, theater and food scenes, but we now have a comedy scene to match. I don't know how I can stress this enough — there's something rare and beautiful happening in the Portland comedy scene right now — and while Pok Pok and Portland Center Stage and Blitzentrapper and Red Fang can all continue to sustain themselves here in Portland, the same isn't necessarily true of comedy scenes. Scenes explode, they jettison their talent to New York, Chicago or Los Angeles, and then they either wither or reload. Portland is verging on explosion. Go see some local comedy. Fucking go do it. Go. GO! Or whatever, stay in and Hulu some shit, I hate you.


text:
"Dad, Would You Sacrifice Me?"
by Rabbi Aron Moss
I need some urgent help. My daughter asked me a question and I'm totally stumped. She learnt in school the biblical story of G-d asking Abraham to sacrifice his son Isaac on the altar. Abraham was ready go through with it, but at the last minute G-d told him that it was just a test. So my daughter turns to me with her big blue eyes and asks, "Dad, if G-d told you to sacrifice me, would you do it?"
You are in a serious pickle. How you answer this could impact your daughter for the rest of her life.
If you say what you want to say, which is "Of course I would never sacrifice you!" then you will have undermined G-d's authority in your daughter's eyes. You are telling her that to disobey G-d is fine if you don't like what He tells you to do.
On the other hand, if you tell her, "I would listen to whatever G-d says," you risk damaging your relationship with your daughter. She may never feel safe with you again, fearing you might have some revelation one night.
So what do you say? Can you look at her sweet face and say you'd sacrifice her? But then, can you tell her it's ok to ignore G-d? The choice seems to be between undermining her faith in G-d, or undermining her trust in her father.
There is only one way out of this pickle. The answer you need to give her is this:
I would absolutely not listen to a command to sacrifice you. Because I would know for sure that such a command did not come from G-d.
In the times of Abraham, the Torah was not yet given. It was before G-d had expressed His moral code for mankind, and so Abraham had no choice but to follow a direct request from G-d, even when it went against his own beliefs.
Not so today. We know very well what G-d wants, as He gave us the Torah with its clear moral instructions. We don't need to rely on our own beliefs.
We know that G-d abhors human sacrifice because He told us so in His Torah.
So what if I hear a heavenly voice telling me to sacrifice my child? I can know one thing for sure: whoever's voice that is, it's not G-d. Any voice or vision or prophecy or dream that tells you to kill an innocent person cannot be an authentic divine revelation. G-d already made clear what He does and doesn't want in His Torah, and that never changes. So any voice that contradicts what is explicit in the Torah must be ignored.
Reassure your daughter that your love of G-d can never override your love for her, it can only make it stronger. And teach her that we don't listen to voices and visions and signs from heaven, we know from the Torah exactly what G-d wants from us.


text:
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Can you smell that salty Mediterranean air? Can you taste that earthy red wine? Can you feel the sun on your neck?
If you're stuck in an office a million miles from Rome, the reality is – you probably can't. But if a trip to Italy isn't on the cards anytime soon, never fear. This September and October, the Lavazza Italian Film Festival is returning for its 15th year and is sure to satisfy your craving for 'Äúla dolce vita'Äù.
The 2014 line-up consists of an impressive mix of 34 features and documentaries, with films including stars such as Monica Belluci, Raoul Bova and Claudio Santamaria. This year the festival will visit eight cities across Australia, treating audiences in Sydney, Melbourne, Canberra, Brisbane, Perth, Adelaide, Hobart and Byron Bay.
With so many stellar films on offer, it's going to be hard to figure out your schedule for the festival. To help you, we've pulled together a few of our favourites from this year's line-up – we even have some double passes up for grabs for a lucky few.
I Can Quit Whenever I Want
Two frustrated but brilliant college professors who can't find a job decide to turn their chemistry skills towards crime. No, we're not recounting the plot of Breaking Bad – although the premise is similar, it's an entirely different kettle of fish. Ultimately, this hilarious parody of middle class turmoil is entertainment in its purest form.
The Wonders
Winner of the Grand Prix at this year's Cannes, this bittersweet and mesmerising film looks at the gradual disappearance of the traditional rural way of life in Italy. It centres on the eldest daughter in a family of German-Italian beekeepers who is desperate to break free from the strict rules of her family. Stars Monica Belluci.
South is Nothing
This stunning cinematic debut from rising talent Fabio Mollo gives a striking look at the atmosphere of fear surrounding the Mafia in southern Italy. It's a coming-of-age tale centred on an angry teenage tomboy who is struggling to find her identity whilst dealing with her brother's suspicious disappearance.
Sacro Gra
Gianfranco Rosi's documentary was the first ever to be awarded the Golden Lion at the Venice Film Festival, scooping the prize up last year. It delves into the stories of the diverse people living around Rome's ring road, the Grane raccordo Anulare, capturing the invisible worlds and possible futures of people living on the fringe.
The Festival's opening night film is an effervescent biopic charting the life of legendary singer, songwriter and accordionist Rocco Granata. This entertaining mix of passion, creativity and music follows Granata's rise from humble beginnings to his eventual emergence as a worldwide musical phenomenon with the release of the song Marina. It's directed by acclaimed, award-winning filmmaker Stijn Conix and produced by the Dardenne brothers.
MELBOURNE: 17 Sept – 12 Oct
SYDNEY: 18 Sept – 12 Oct
CANBERRA: 23 Sept – 15 Oct
PERTH: 24 Sept – 15 Oct
BRISBANE: 1 Oct – 22 Oct
ADELAIDE: 2 Oct – 22 Oct
BYRON BAY: 9 Oct – 15 Oct
HOBART: 16 Oct – 22 Oct
For more information, venue details and to purchase tickets click HERE.
To celebrate the festival's return, we have ten general double passes to give away. For your chance to win simply complete the form below and tell us in 25 words or less which film you're most excited about in this year's line-up and why?
Competition closes 12pm Monday 8 September.


text:
Oracle Service Repair Centers
Home >> Oracle Service Centers >> Oracle Service Centers Idaho
Oracle Service Centers in Boise
Full list of all Oracle Service Repair Centers in Boise, Idaho. All companies with the best technicians in the repair and servicing of Oracle products.
Below are listed addresses, telephone number, fax and opening days of the Oracle Service Repair Centers in Boise, Idaho.
Oracle technical support center in Boise, Idaho
Oracle Corp
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Boise, ID 83702
(208) 333-7020
250 S 5th St
Boise, ID 83702
(208) 333-7020
Support for Oracle products
Phone: 1-800-633-0738
Zip Code: 83701


text:
The Collation of the Revd Frances Trickey
Date & Time: Tue 25 Apr - 7.00pm to 9.00pm
This special service of collation, induction and installation is the Church of England's formal welcome for our new vicar, the Revd Frances Trickey.
The Rt Revd Dr Jo Wells, Bishop of Dorking, will conduct the collation, and the Ven Paul Bryer, Archdeacon of Dorking, will conduct the induction and installation.
Everyone is welcome and encouraged to attend this special event at St Andrew's. Please arrive in good time as there will be many in attendance, and it may take a while to get everyone seated.
Refreshments will be available after the service in the Village Centre, where we can offer Frances a more informal welcome.


text:
Sapormoina Tourism
Visit Sapormoina - Best of Sapormoina
A place in India, Sapormoina is an interesting place to visit, given its unique culture, history and character. After your splendid visit to Sapormoina, you can proceed to an important near-by city of Cherrapunji. Add Cherrapunji to your vacation plan, it has an interesting bunch of activities to do on your visit like Nohkalikai Falls, Sa-i-mika Park, Mawsmai Cave. Also, to reach Sapormoina, you'll have to take a flight to Cherrapunji; so its not really a detour. And even if it is, the city is worth paying at least a quick visit. Most online packages to this city are of 1-2 days.
Yes,it is that simple really! Enjoy your trip! Keep travelling!
Explore the travel itinerary planning tool for your visit to Sapormoina and create a flawless plan in few simple steps!


text:
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Bracelet Dogtag Black
Full Product Description
Bracelet Dogtag Black was published by Kerusso in August 2015 and is our 39340th best seller. The ISBN for Bracelet Dogtag Black is 612978914663.
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Details for Bracelet Dogtag Black
|Kerusso (August 2015)
|Product Code
|Page last updated
|23rd March 2017


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Terms & Conditions Apply
Mon - Fri 9:00am - 5:00pm
Slane Cycles Time:
Saracen Amplitude Wave Bmx 2015 Specification
Frame: : Amplitude 1020 Hi-Ten steel frame / MID BB
Rear Shock: : N/A
Fork: : 1020 Hi-Ten steel Unicrown fork
Headset: : TH-888
Shifters: : N/A
Rear derailleur: : N/A
Front derailleur: : N/A
Chainset: : 4130 Cro-Mo cranks 3-piece design with 25T steel chainring
Bottom Bracket: : Sealed cartridge with 8T spline / MID type
Chain: : KMC Z410
Cassette: : 9T Freewheel
Rims: : Alloy 20 inch 36 hole
Hubs: : Formula DX-21 front / Formula DX-43 with 14mm axle rear
Spokes: : Steel 14g
Tyres: : Saracen BMX 20 x 2.2 inch
Brakes: : Alloy Caliper front / Alloy U-Brake rear
Brake levers: : Alloy 2 finger
Handlebars: : Saracen 1020 2pc bar 28 inch wide / 8 inch rise
Grips: : Saracen Moto dual-density grip
Stem: : Saracen Alloy A-Head Front-loader
Saddle: : Saracen Custom Dirtjump
Seatpost: : Steel / 25.4 mm
Pedals: : Resin Platform BMX
Delivery Information
Delivery to the UK and Ireland : 1- 2 days. Next day delivery to UK destinations is available at an additional charge, depending on item size and weight, details can be found at checkout.
European Destinations : 3 to 5 days
USA, Canada, Japan, Australia and other Far East Destinations 4 to 7 days.
Rest of World: 5- 10 days.
A tracking number with either Royal Mail or Parcel Force web address is emailed to all customers on dispatch of goods.
Further information on shipping charges.
We accept the return of goods only if they are unopened (except in cases where the item has to be tried for fit) and in their original condition. If you return goods as detailed, within 30 days, we will issue a full refund for the price you paid for the item.
If there is a fault or malfunction with an item please return the goods to us with the original receipt and packaging.We will forward the items to the relevant manufacturer's warranty department. Delays in return of warranty items are the responsibility of the manufacturers and we cannot be held responsible, we will however endeavour to have all warranty issues resolved as speedily as possible.
If the item returned is found not to be defective or sent by mistake by us; you will be responsible for the postage charges and the costs of any other services provided to you in connection with your purchase. If items are returned for a straight exchange due to change of size/colour a further postage and package charge will be have to be made.


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2017 is going to be Apple's 10th anniversary. Since iPhone 7 and iPhone 7 Plus are already released, rumors are surfacing throughout the internet about Apple's next flagship bearer, iPhone 8. From rumors and leaks, it is clear that Apple will make a full redesign of iPhone with iPhone 8.
As per an anonymous industry source, iPhone 8 will have glass in the rear instead of aluminum. As per reports, the glass back will be supplied by China's Biel Crystal Manufactory and Lens Technology. There will be a metal frame, most probably aluminum or a stainless steel frame holding the front and the glass back together.
There is news that there might be 3 size variants of the handset; 4.7-inch, 5.5-inch, and a 5-inch. The report further claims that the 5.5-inch variant will sport a dual-curved Super AMOLED display, while the other two variants will sport LTPS LCD display like previous models. The handset is expected to come with wireless charge support.


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I Think Smoking Is Ugly
Personal Stories, Advice, and Support 26 People
Smoking Is Cool!not really. I find nothing attracting or cool about smoking. "Oh look at me! I''m 14 and have a cigarette!" seriously...? That is so not a thing to brag about.
Turbulence 18-21, M 5 Responses 2 Jun 19, 2009