Abstract: Signal amplifiers having a non-linear transfer function. A high speed (high bandwidth) circuit with a non-linear transfer function over a limited range of input signal is provided. By appropriate choice of components, the non-linear transfer function can be used to accurately approximate any monotonic function such as a square root transfer function. In another aspect, a piecewise non-linear circuit arrangement using a set of non-linear sub-circuits is provided to accurately generate a desired non-linear transfer function over an extended dynamic range of input signal. In one implementation of such a circuit, each of the sub-circuits approximates the desired non-linear function over a portion of the input range.

Abstract: A device for dynamically biasing an ion optic element, for example, in a mass spectrometer. The device includes a voltage source, a first ion optical element coupled with the voltage source, a second ion optical element resistively coupled with the first ion optical element; and a pulse generator capacitively coupled with the second ion optical element. The pulse generator is configured to apply a series of pulses to the second ion optical element. In steady state operation, a dynamic voltage bias is generated between the first ion optical element and the second ion optical element. The dynamic voltage bias is controllable by controlling the characteristics of the applied pulses, such as the pulse width, pulse amplitude, and pulse repetition rate of the applied pulses.

Abstract: Signal amplifiers having a non-linear transfer function. A high speed (high bandwidth) circuit with a non-linear transfer function over a limited range of input signal is provided. By appropriate choice of components, the non-linear transfer function can be used to accurately approximate any monotonic function such as a square root transfer function. In another aspect, a piecewise non-linear circuit arrangement using a set of non-linear sub-circuits is provided to accurately generate a desired non-linear transfer function over an extended dynamic range of input signal. In one implementation of such a circuit, each of the sub-circuits approximates the desired non-linear function over a portion of the input range.

Abstract: Laser desorption/ionization time-of-flight mass spectrometer (“LDI-TOF-MS”) devices, and methods, that accurately measure the mass of analytes contained in a sample and which also measure the quantities of analytes present in a sample in a consistent manner from instrument-to-instrument and over time on a single instrument. In particular, the invention provides LDI-TOF-MS devices and methods in which: 1) the energy of the laser pulse and the area of the sample illuminated (fluence) is consistent and controlled so as to produce consistent conditions for analyte desorption and ionization; 2) the mass analyzer behaves in a reproducible manner; and 3) the detection system produces a signal that consistently represents the arrival of ions of different masses.

Abstract: Systems and methods for rastering a series of illumination pulses across the surface of a sample under investigation in a mass spectrometer system so as to create a two dimensional illumination pattern (raster pattern) on the sample. A probe interface that engages a probe is configured to translate the probe along a first direction, and a pulse deflection mechanism is configured to vary the pulse-probe intersect position along a second direction. A control system, implementing a rastering algorithm, provides control signals to the pulse deflection mechanism to adjust the pulse path and the probe translation mechanism to adjust the probe position so that each illumination pulse impinges on one of a plurality of addressable locations on the sample. The resulting raster pattern may cover the entire sample or one or more portions of the sample, depending on the spot size and the displacement distances for each pulse along the first and second directions.