Joseph M Slater

6351306, Feb 26, 2002

Oct 19, 1999

09/420483

James M. Tedesco - Livonia MI
Joseph B. Slater - Dexter MI

Kaiser Optical Systems, Inc. - Ann Arbor MI

G01N 344

356301, 356318, 2504581

Methods and apparatus are disclosed for calibrating remote optical probe configurations of the type wherein a spectrum emitted by a sample is delivered to a spectrograph for analysis using fluorescence, Raman detection or other dispersive techniques. The invention may be used to calibrate the spectrograph wavelength axis, the system spectral response or intensity axis, and the wavelength of the laser used for excitation. A collection optical fiber having a first end for receiving wavelengths emitted by the sample has a second end for delivering the wavelengths to a base unit containing the spectrograph. A calibration optical fiber is used to deliver an optical calibration signal to a point proximate to the first end of the collection optical fiber, and an optical element is used to direct the optical calibration signal into the collection optical fiber so that the spectrograph receives both the wavelengths emitted by the sample and the optical calibration signal. A neon reference lamp is preferably used to calibrate the spectrograph wavelength axis, and a tungsten halogen lamp is employed to calibrate the system spectral response or intensity axis. The invention is applicable to a variety of configurations, including process monitoring environments utilizing a plurality of probeheads.

6757060, Jun 29, 2004

Jan 24, 2003

10/350499

Kevin Davis - Ann Arbor MI
Joseph B. Slater - Dexter MI

Kaiser Optical Systems - Ann Arbor MI

G01J 344

356301, 356624

Disclosed is a method of positioning a focused image within a sampled medium in an optical measurement probe of the type wherein a focused sampling image is transmitted through a window having a surface facing a sampled medium. A test medium is measured, preferably through the window, and the magnitude of an optical signal associated with the test medium is then compared to the magnitude of an optical signal associated with the window, and the result of the comparison is used to position the focused image. Typically, the magnitudes of optical signals are representative or Raman scattering or another wavelength-selective radiative sampling process such as fluorescence detection. The method is not limited in terms of window composition, and is compatible with sapphire windows commonly used in industry. Nor is the invention limited in terms of test medium though, in the preferred embodiment a fluid hydrocarbon such as isopropyl alcohol is used.

7148963, Dec 12, 2006

Dec 9, 2004

11/007969

Harry Owen - Ann Arbor MI, US
David J. Strachan - Timonium MD, US
Joseph B. Slater - Dexter MI, US
James M. Tedesco - Livonia MI, US

Kaiser Optical Systems - Ann Arbor MI

G01N 21/64

356301, 356317

A compact Raman/fluorescence probe is capable of collecting spectra from a relatively large spot size as compared to traditional confocal Raman probes. The inventive probe collects spectra from an area or 1 mm or greater, preferably 3–12 mm or more, compared to current instruments which utilize spot sizes on the order of 2–60 microns. The larger spot size facilitates the collection of statistically useful data from inhomogeneous and laser-sensitive samples, among other applications. Potential pharmaceutical applications include tablet dosage level measurements, as well as online and at-line quality-control (QC) monitoring opportunities. Other applications include tablet identification as a forensic tool to identify counterfeit pharmaceutical products; granulation and blend uniformity for improved formulation via better process understanding, and reactor cleanliness validation.

7158225, Jan 2, 2007

Jan 23, 2004

10/764319

James M. Tedesco - Livonia MI, US
Joseph B. Slater - Dexter MI, US
Kevin L. Davis - Ann Arbor MI, US
Ronald C. Fairchild - Ann Arbor MI, US
John W. Baughn - Clinton MI, US

Kaiser Optical Systems - Ann Arbor MI

G01J 3/33
G01J 3/44
G01N 21/64
G01N 21/65

356301, 356318, 2504581

A multi-channel, reconfigurable fiber-coupled Raman instrument uses fiber optic switches for laser and calibration light routing to facilitate automated calibration, diagnosis and operational safety. The system allows wavelength axis calibration on all channels; laser wavelength calibration (including multiple and/or backup laser options); fiber coupling optimization; fault detection/diagnosis; and CCD camera binning setup. In the preferred embodiment, dedicated calibration channels surround data channels on a 2-dimensional CCD dispersed slit image implemented using a unique cabling architecture. This “over/under” calibration interpolation approach facilitates quasi-simultaneous or sequential calibration/data acquisitions. CCD binning between sequential calibration and data acquisitions enables higher density multi-channel operation with tilted images based upon a multiplexed grating configuration. A diamond sample is used as a Raman shift reference for laser calibration, preferably in the form of a small disc sampled with an edge-illuminating probe using two unfiltered fibers.

7307804, Dec 11, 2007

Jan 17, 2006

11/333046

James M. Tedesco - Livonia MI, US
Joseph B. Slater - Dexter MI, US

Kaiser Optical Systems - Ann Arbor MI

G02B 5/04
G02B 7/18

359831, 359837, 359 15, 359566, 385 37

Thermally stable GRISMs comprise a substrate and cover plate composed of a first material keeps the spatial frequency of the grating stable with temperature, and a prism composed of a second material having lower thermal coefficient of refractive index than that of the first material. In the preferred embodiment, the first material is fused silica, and the second material is BK7 glass.

7692786, Apr 6, 2010

Oct 17, 2007

11/873718

James M. Tedesco - Livonia MI, US
Joseph B. Slater - Dexter MI, US

Kaiser Optical Systems - Ann Arbor MI

G01J 3/44
G01N 21/65

356301

Raman measurement apparatus optimized for gaseous and other low-concentration samples includes a focusing objective that uses only first-surface mirrors instead of lenses, thereby dramatically reducing background noise. In the preferred embodiment, the focusing and collimation functions performed by the objective section are performed by an off-axis parabolic mirror. A spherical first-surface mirror opposing the parabolic mirror re-images the counter-propagating beam back through the same focus for re-collimation by the parabolic mirror. A probe-head section operative to generate the counter-propagating beam has substrates and surfaces arranged such that the excitation beam does not pass through any substrates after it is filtered by the bandpass coating, thereby further decreasing background signals. Additionally, when the objective section includes the opposing spherical mirror, the excitation beam is collected substantially in its entirety and neutralized out of the collection path by the probe-head section.

20130321812, Dec 5, 2013

May 28, 2013

13/903052

James M. Tedesco - Livonia MI, US
Joseph B. Slater - Dexter MI, US

KAISER OPTICAL SYSTEMS - Ann Arbor MI

G01J 3/44

356402

Methods and apparatus facilitate dynamic range balancing for multi-component peaks of widely varying magnitude in an optical spectrometer. In a specific embodiment, filters attenuate the C—H stretch region to produce a better fit of a multi-component hydrocarbon Raman spectrum to the dynamic range of a CCD detector. The filter may be translated into and out of the collimated collection beam to achieve a varying degree of attenuation. In certain applications, the filter is insertable into a collimated collection beam within a fiber-optic probe head to collect Raman spectra. The invention may include optical elements to create the collimated collection beam if not already present or not suitable for insertion of the filter. A second filter, an “opaque” or neutral density filter, may be insertable into the collimated collection beam to attenuate a broad spectral response within and outside the spectral range.

20140036347, Feb 6, 2014

Aug 1, 2012

13/564461

James M. Tedesco - Livonia MI, US
Joseph B. Slater - Dexter MI, US

Kaiser Optical Systems - Ann Arbor MI

H01S 3/30

359334

Raman signal amplification apparatus comprises an ellipsoidal reflector providing a first real focus f and second real or virtual focus f both foci being situated within a sample volume. When an input laser excitation beam having an initial numerical aperture (NA) is focused onto one of the foci, the beam is reflected by the reflector and refocused onto alternating foci, such that the NA of the reflected optical path progressively increases for higher efficiency collection of Raman emissions from the multiple foci. The ellipsoidal reflector may be a half section providing a single real focus f with a flat reflector producing a mirror image of the ellipsoidal reflector, such that f is a virtual focus occupying the same point as f Alternatively, the ellipsoidal reflector may have a first half section with a first real focus f and a second half section with a second real focus f