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Rutgers, The State University of New Jersey

Alexei Ermakov

Barbara Jane Hinch

Leonard C Feldman

Xiuyan Li

Eric Garfunkel

Torgny Gustafsson

Systems and methods for measuring a curvature radius of a sample. The methods comprise: emitting a light beam from a laser source in a direction towards a beam expander; expanding a size of the light beam emitted from the laser source to create a broad laser beam; reflecting the broad laser beam off of a curved surface of the sample; creating a plurality of non-parallel laser beams by passing the reflected broad laser beam through a grating mask or a biprism; using the plurality of non-parallel laser beams to create an interference pattern at a camera image sensor; capturing a first image by the camera image sensor; and processing the first image by an image processing device to determine the curvature radius of the sample.

Systems and methods for real time measurement of surface curvature and thermal expansion of small samples

Methods of operation of electrostatic ion trap mass spectrometers in which ions are autoresonantly driven at selected higher integer (&#x3e;2) multiples of ion oscillation frequencies are provided. Excitation at multiples higher than the fundamental or double the fundamental ion oscillation frequency significantly improves both signal intensity and mass resolution. Each method allows excitation exclusively at one selected frequency that is an integer multiple of an ion's natural oscillation frequency, and thereby virtually eliminates ion excitation at unwanted harmonic frequencies. The resultant mass spectra are therefore clean, and do not display spectral features associated with rf excitation at unintended multiple harmonic frequencies. This has been demonstrated explicitly for 4&#xd7; and 6&#xd7; modes, and it is fully implementable at any odd or even multiples of ion oscillation frequencies. With implementation of a new method, mass spectrometers can be operated at faster mass scan rates, giving faster response times, without degradation of signal to noise or resolution over the existing technology instruments. Equivalently, with implementation of a new method, mass spectrometers can be operated with superior signal to noise ratios without degradation of response times or resolution.

Electrostatic ion trap mass spectrometer utilizing autoresonant ion excitation and methods of using the same

The inventive apparatus measures workfunction values using deflection of an electron beam without direct contact of the electron beam with the sample surface. The apparatus, mounted within a vacuum chamber, includes an electron gun, a position sensitive electron detector, and a sample. The sample is located such that an electron beam emanating from the gun can approach the surface and then be deflected into the position sensitive electron detector. Workfunction values are then derived from a measured deflected-electron position distribution.

Electron beam apparatus for work function measurements

The inventive apparatus is capable of accurate contactless sample conductance measurements. In accordance with the invention, a three coil apparatus for inductive conductance measurements comprises at least three coils, (or inductive devices,) a radio frequency (RF) generating device in conjunction with electronic circuitry for radio frequency amplitude measurement and comparison of radio frequency amplitude signals. The attainable accuracy is improved over that achieved using other conventional non-contact means by processing the differences of RF amplitude signals observed across pairs of sensing coils. Also, this invention does not require more complex RF signal processing, such as analysis of in-phase and quadrature voltage data. In a preferred embodiment, the natural resonance frequencies of the two sensing coils are tuned slightly off the RF driving frequency such that a monotonic response across a wide range of the sample's conductivity is achieved. The sensitivity of the apparatus to low sample conductances is thereby further enhanced.

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Piscataway, NJ, United States of America

Alexei Ermakov