Abstract: An apparatus and method for analyzing particulates in a sample is disclosed. The method includes placing the sample on a moveable stage in an apparatus having a tunable MIR light scanner and a visible imaging system, the stage moving between the MIR light scanner and the visible imaging system, providing a visible image of the sample, and receiving user input as to a region of the sample that is to be analyzed. The sample is then moved to the MIR light scanner, the MIR light scanner generating an MIR light beam that is focused to a point on the specimen and measuring light reflected from the specimen. The specimen is then scanned at a first MIR wavelength by moving the specimen relative to the MIR light beam, and particles are identified that meet a selection criterion. The MIR absorption spectrum of each of the identified particle is then automatically measured.

Abstract: An ATR scanner and method for calibrating the same are disclosed. The scanner includes an ATR objective having a reflecting face and an optical port adapted to receive a first light beam, and to focus the first light beam to a point, at a location on the reflecting face such that the first light beam is reflected by the reflecting face and no portion of the first light beam strikes the reflecting face at an angle greater than the critical angle. A detector measures an intensity of light reflected from the reflecting face. A controller controls the location of the focal point and determines an intensity of light that was incident on the reflecting face as a function of the position on the reflecting face and an intensity of light that was reflected from the reflecting face as a function of position on the reflecting face.

Abstract: An apparatus and method for analyzing particulates in a sample is disclosed. The method includes placing the sample on a moveable stage in an apparatus having a tunable MIR light scanner and a visible imaging system, the stage moving between the MIR light scanner and the visible imaging system, providing a visible image of the sample, and receiving user input as to a region of the sample that is to be analyzed. The sample is then moved to the MIR light scanner, the MIR light scanner generating an MIR light beam that is focused to a point on the specimen and measuring light reflected from the specimen. The specimen is then scanned at a first MIR wavelength by moving the specimen relative to the MIR light beam, and particles are identified that meet a selection criterion. The MIR absorption spectrum of each of the identified particle is then automatically measured.

Abstract: An ATR scanner and method for calibrating the same are disclosed. The scanner includes an ATR objective having a reflecting face and an optical port adapted to receive a first light beam, and to focus the first light beam to a point, at a location on the reflecting face such that the first light beam is reflected by the reflecting face and no portion of the first light beam strikes the reflecting face at an angle greater than the critical angle. A detector measures an intensity of light reflected from the reflecting face. A controller controls the location of the focal point and determines an intensity of light that was incident on the reflecting face as a function of the position on the reflecting face and an intensity of light that was reflected from the reflecting face as a function of position on the reflecting face.

Abstract: An imaging scanner and a method for using the same are disclosed. The scanner includes a variable attenuator adapted to receive a light beam generated by a MIR laser and that generates an attenuated light beam therefrom characterized by an attenuation level. The scanner includes an optical assembly that focuses the attenuated light beam to a point on a specimen. A light detector measures an intensity of light leaving the point on the specimen, the light detector being characterized by a detector dynamic range. A controller forms a plurality of MIR images from the intensity as a function of position on the specimen, each of the plurality of MIR images being formed with a different level of attenuation of the light beam. The controller combines the plurality of MIR images to generate a combined MIR image having a dynamic range greater than the detector dynamic range.

Abstract: A method is provided for controlling an FM-AFM including a cantilever having a resonant frequency and an excitation system configured to oscillate the cantilever in response to a drive signal. The method includes determining latency of the excitation system; receiving a deflection signal indicating a deflection of a cantilever tip; mixing the deflection signal with a first sine signal output by a PLL indicating a frequency shift of a frequency response of the cantilever; measuring the frequency shift in response to the drive signal; determining spurious phase of the cantilever based on the determined latency, the resonant frequency of the cantilever, and the measured frequency shift; providing a second sine signal having a phase that is advanced by the determined spurious phase to preemptively compensate for subsequent spurious phase of the cantilever; and driving the excitation system using the second sine signal with an adjusted amplitude as the drive signal.

Abstract: A scanner and method for using the same are disclosed. The scanner includes a stage, a MIR light source, an imaging system, and a controller. The stage is adapted to hold a specimen to be imaged and to move the specimen in a first direction and in a second direction that is orthogonal to the lateral direction. The imaging system forms an image plane of the specimen when the stage is positioned at a second direction distance, z, from a known point in the imaging system. The imaging system forms a plurality of different image planes of the specimen at the illumination wavelength. Each of the plurality of image planes is characterized by a different value of z, the controller determining a value of z for each of a plurality of points on the specimen at which the point on the specimen is in focus.

Abstract: A scanner and an attenuated total reflection (ATR) objective for use in such scanners are disclosed. The ATR objective includes first and second optical elements and an input port. The input port receives an input collimated light beam that is focused to a point on a planar face of the first optical element by the second optical element such that substantially all of that portion is reflected by the planar face and no portion of the input beam strikes the planar face at an angle less than the critical angle. The second optical element also generates an output collimated light beam from light reflected from the planar thce that is characterized by a central ray that is coincident with the central ray of the input collimated light beam. A light beam converter receives the first collimated light beam and generates the input collimated light beam therefrom.

Abstract: A method for optimizing loop gain of an atomic force microscope (AFM) apparatus includes determining a change in gain of the physical system and adjusting a controller frequency response of the controller in an AFM loop to compensate for the determined change in gain. The AFM loop has a corresponding loop response that includes the product of the controller frequency response and a physical system response of the physical system.

Abstract: An atomic force microscope (AFM) comprises a physical system and a controller comprising a plurality of digital filters and configured to control the physical system. The AFM is tuned by performing automatic loop shaping on a loop response defined by a frequency response of the physical system and a frequency response of the controller, and adjusting a gain of the controller according to a peak in a magnitude of the loop response.

Abstract: An imaging scanner and a method for using the same are disclosed. The scanner includes a variable attenuator adapted to receive a light beam generated by a MIR laser and that generates an attenuated light beam therefrom characterized by an attenuation level. The scanner includes an optical assembly that focuses the attenuated light beam to a point on a specimen. A light detector measures an intensity of light leaving the point on the specimen, the light detector being characterized by a detector dynamic range. A controller forms a plurality of MIR images from the intensity as a function of position on the specimen, each of the plurality of MIR images being formed with a different level of attenuation of the light beam. The controller combines the plurality of MIR images to generate a combined MIR image having a dynamic range greater than the detector dynamic range.

Abstract: A scanner and method for using the same are disclosed. The scanner includes a stage, a MIR light source, an imaging system, and a controller. The stage is adapted to hold a specimen to be imaged and to move the specimen in a first direction and in a second direction that is orthogonal to the lateral direction. The imaging system forms an image plane of the specimen when the stage is positioned at a second direction distance, z, from a known point in the imaging system. The imaging system forms a plurality of different image planes of the specimen at the illumination wavelength. Each of the plurality of image planes is characterized by a different value of z, the controller determining a value of z for each of a plurality of points on the specimen at which the point on the specimen is in focus.

Abstract: A scanner and an attenuated total reflection (ATR) objective for use in such scanners are disclosed The ATR objective includes first and second optical elements and an input port. The input port receives an input collimated light beam that is focused to a point on a planar face of the first optical element by the second optical element such that substantially all of that portion is reflected by the planar face and no portion of the input beam strikes the planar face at an angle greater than the critical angle. The second optical element also generates an output collimated light beam from light reflected from the planar face that is characterized by a central ray that is coincident with the central ray of the input collimated light beam. A light beam converter receives the first collimated light beam and generates the input collimated light beam therefrom.

Abstract: A method for determining a loop response for an apparatus for an atomic force microscope is disclosed. The method comprises: determining a loop response for an on-surface movement of a cantilever over a frequency range; determining a loop response for an off-surface movement of the cantilever over the frequency range; and adjusting an output of the controller at a frequency based on the loop response for the off-surface movement. An atomic force microscopy system is disclosed.

Abstract: An atomic force microscope (AFM) system comprises a cantilever arm attached to a probe tip. The system controls a height of the cantilever arm to press the probe tip against a sample and then separate the probe tip from the sample, to detect a disturbance of the cantilever arm after the separation of the probe tip from the surface, and to engage active damping of the cantilever arm to suppress the disturbance.

Abstract: A method is provided for controlling an FM-AFM including a cantilever having a resonant frequency and an excitation system configured to oscillate the cantilever in response to a drive signal. The method includes determining latency of the excitation system; receiving a deflection signal indicating a deflection of a cantilever tip; mixing the deflection signal with a first sine signal output by a PLL indicating a frequency shift of a frequency response of the cantilever; measuring the frequency shift in response to the drive signal; determining spurious phase of the cantilever based on the determined latency, the resonant frequency of the cantilever, and the measured frequency shift; providing a second sine signal having a phase that is advanced by the determined spurious phase to preemptively compensate for subsequent spurious phase of the cantilever; and driving the excitation system using the second sine signal with an adjusted amplitude as the drive signal.

Abstract: An atomic force microscope (AFM) system comprises a cantilever arm attached to a probe tip. The system controls a height of the cantilever arm to press the probe tip against a sample and then separate the probe tip from the sample, to detect a disturbance of the cantilever arm after the separation of the probe tip from the surface, and to engage active damping of the cantilever arm to suppress the disturbance.

Abstract: A method for determining a loop response for an apparatus for an atomic force microscope is disclosed. The method comprises: determining a loop response for an on-surface movement of a cantilever over a frequency range; determining a loop response for an off-surface movement of the cantilever over the frequency range; and adjusting an output of the controller at a frequency based on the loop response for the off-surface movement. An atomic force microscopy system is disclosed.

Abstract: An atomic force microscope (AFM) comprises a physical system and a controller comprising a plurality of digital filters and configured to control the physical system. The AFM is tuned by performing automatic loop shaping on a loop response defined by a frequency response of the physical system and a frequency response of the controller, and adjusting a gain of the controller according to a peak in a magnitude of the loop response.

Abstract: An atomic force microscope (AFM) apparatus for determining a topography of a sample surface is disclosed. The AFM apparatus comprises: a controller having a controller frequency response and being configured to provide a controller output signal. The controller comprises an integrator that provides an integrator output signal, and a filter block. The AFM apparatus also comprises a physical system having a physical system response and being configured to receive the controller output signal and to provide a probe height in response to the controller output signal. The physical system comprises an actuator configured to maintain a deflection of a probe tip relative to the sample surface. The deflection being is indicated by a deflection signal, and the filter block of the controller provides an inverse of the physical system response, such that the probe height is substantially equal to the integrator output signal.