Nirsystems Incorporated

Foss Nirsystems, Inc.

Pacific Scientific Company

Kenneth P VonBargen

Philip A McGee

Frank A DeThomas

Karl H Norris

In a flow cell, a flow cell body defines a fluid passageway. Opposed fiber optic cable assemblies with sapphire windows project into the fluid passageway. The fiber optic cable assemblies are axially adjustable in position to provide a capability of varying the path length for the light beam passing between the sapphire windows of the fiber optic cable assemblies in the fluid flowing in the fluid flow path. The path length is precisely settable by means of a feeler gauge which is inserted in a position between the windows of the fiber optic cable assemblies by means of a fixture inserted into the flow path. The fixture is in two parts which engage the fiber optic cable assemblies from opposite ends of the flow path and the fixture is provided with an oblong slot to properly orient the feeler gauge in the flow path between the fiber optic cable assemblies.

Flow cell

In a spectroscopic instrument having a spherical grating to disperse incident light into a spectrum, the grating is oscillated on axis to scan the light passing through an exit slit through the spectrum or a portion of the spectrum. The axis of rotation of the grating is shifted to be displaced from tangent to the center of the spherical grating so that the light passing through the exit slit is substantially focused throughout the spectrum scanned by the instrument. The grating is mounted in the holder to shift the center of gravity of the grating and the holder to be on the axis on which the grating is pivoted.

Spectroscopic instrument with offset grating to improve focus

An infrared spectroscopy instrument having a transflectance type probe with an adjustable path length is disclosed. The instrument is adaptable to take both reflectivity and transmission type measurements. According to a method of use of the instrument discloses a material undergoing a change in viscosity and optical density can be measured by appropriately adjusting the path length to allow a sample of the material to enter. At a first interval, a first measurement is made using the instrument according to a transmission protocol. A second measurement is made of the sample when the sample is viscous and optically dense at a second interval using the same instrument according to a reflectivity measurement protocol.

Transflectance probe having adjustable window gap adapted to measure

In a fiber optic probe for an infrared analysis instrument, a window block made of sapphire is provided having an inner face in the shape of a truncated cone. A fiber optic cable has its distal end adjacent to the inner face of the window block and the optic fibers in the distal end are segregated into transmitting fibers adjacent to said conical section of the inner face of the window block and receiving fibers abutting the central circular portion formed by the truncated cone shape of the inner face. A cylindrical separator separates the receiving and transmitting fibers at the distal end of the fiber optic cable.

Fiber optic probe with truncated cone window block for infrared spectral

In a system for measuring moisture content of powder, such as powdered milk while the powder is being dried, the powder is contained in a fluidized bed and a fiber optic probe is inserted through the wall of the container of said bed to be immersed in the fluidized bed. The fluidized bed continuously scrubs the outer surface of the probe window and prevents it from being coated with the powder. Near infrared light is transmitted through a cable optic fiber and said probe to irradiate the powder in said fluidized bed and is reflected back from the powder into said probe and transmitted by said fiber optic cable to a spectroscopic analyzing instrument. The fiber optic probe includes a sapphire rod having a back surface abutting the end of the fiber optic cable and an angled front surface. The front of the probe is closed by a quartz window spaced from the angled front surface of the sapphire rod and held in position by an inwardly directed flange on the outer tubular casing of the fiber optic probe. The front window is provided with an outwardly directed flange and an O-ring is sandwiched between the flange on the window and the inwardly directed flange on the distal end of the probe to provide a seal to prevent powder from getting in the probe.

Fiber optic probe

System for measuring the moisture content of powder and fiber optic

In an optical instrument for infrared spectral analysis of powder, an improved fiber optic probe is provided. Fiber optics carry light to and from the probe and the fiber optics terminate in the probe in a fiber optic endface. A sapphire rod is positioned to abut the fiber optic endface. The sapphire rod has a distal endface arranged at slightly less than one-half the maximum acceptance angle of the optic fibers in the probe.

Powder fiber optic probe having angled end in NIR optical analyzing

In an optical instrument for measuring particles in the size range of 0.5 microns to 300 microns, a laser beam is caused to pass through a sample stream of liquid containing particles to be measured. A photodetector detects a portion of the direct laser beam passing through the sample stream and the amplitudes of the pulses generated by this first photodetector provide a measurement of particles in the size range of 10 to 50 microns. A second photodetector detects forward scattered light from the laser beam passing through the liquid sample stream. The amplitudes of pulses generated by the second photodetector provide a measurement of pulses in the size range of 0.5 microns to 10 microns and the durations of pulses generated by the second photodetector provide a measurement of pulses in the size range of 50 to 300 microns.

Growing community of inventors

Berwyn Heights, MD, United States of America

Kenneth P VonBargen