Patents Assigned to International Sensor Technology, Inc.
  • Patent number: 5124993
    Abstract: A laser power control system is disclosed which detects the power of an emtted laser beam. The detection is preferably accomplished by splitting the beam using a beam splitter to form a detector laser beam which includes a limited portion of the beam. The beam is preferably split after polarization to obvate changes in detected power associated with polarization changes which can occur in the laser. The detector beam can be detected either continuously or intermittently, such as by using a chopping wheel which intermittently passes and interrupts the detector beam. The detected laser beam power signal is compared against a predetermined set point or preprogrammed time variable laser power profile thus allowing desired laser power to be achieved. The laser beam is also preferably equalized to achieve a more uniform cross-sectional laser power density.
    Type: Grant
    Filed: June 12, 1989
    Date of Patent: June 23, 1992
    Assignee: International Sensor Technology, Inc.
    Inventors: Peter F. Braunlich, Wolfgang Tetzlaff
  • Patent number: 5083031
    Abstract: Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.
    Type: Grant
    Filed: April 24, 1989
    Date of Patent: January 21, 1992
    Assignee: International Sensor Technology, Inc.
    Inventors: James W. Hoelsher, Joel E. Hegland, Peter F. Braunlich, Wolfgang Tetzlaff
  • Patent number: 5081363
    Abstract: Disclosed is a laser dosimeter reading apparatus having a controllable optical laser converter for providing multiple stimulating laser beams. The converter laser dosimeter reader can be used to stimulate or otherwise treat dosimeter elements to perform two or more distinct processes on a particular dosimeter element. Additionally, the convertible dosimeter reader can be used to read multiple different types of dosimeter elements contained on a single dosimeter badge, thereby allowing a badge to be read in a multi-stage reading operation in a single dosimeter reader which is preferably automated. The optical laser converter includes a converter block assembly which defines multiple optical pathways therethrough. The convert block assembly is movable between different positions to align the different optical pathways with an incoming laser beam.
    Type: Grant
    Filed: April 26, 1991
    Date of Patent: January 14, 1992
    Assignee: International Sensor Technology, Inc.
    Inventors: Wolfgang Tetzlaff, James W. Hoelscher, Peter F. Braunlich, Carl D. Bloomsburg
  • Patent number: 5049754
    Abstract: Disclosed is a radiation dosimeter reading apparatus designed to disassemble, reposition, read, and reasemble radiation dosimeter badges. The dosimeter reading apparatus includes a dosimeter badge chuck assembly which engages a dosimeter badge in an infeed dosimeter badge holder. The chuck assembly engages the dosimeter badge using a set of tamper element prongs which depress a tamper ring which forms part of the dosimeter badge. The depression of the badge tamper ring releases a locking ring which also forms part of the dosimeter badge. Once the locking ring is freed, then another set of prongs on the chuck assembly are rotated to route the locking ring of the badge and thereby release a disk-shaped dosimeter badge insert. The chuck assembly is further adapted to grasp the released insert by contracting the tamper element prongs inwardly against the perphery of the disk-shaped insert to hold the inset on the chuck assembly.
    Type: Grant
    Filed: June 26, 1989
    Date of Patent: September 17, 1991
    Assignee: International Sensor Technology, Inc.
    Inventors: James W. Hoelscher, Carl D. Bloomsburg
  • Patent number: 5041734
    Abstract: Disclosed is a laser dosimeter reading apparatus having a controllable optical laser converter for providing multiple stimulating laser beams. The convertible laser dosimeter reader can be used to stimulate or otherwise treat dosimeter elements to perform two or more distinct processes on a particular dosimeter element. Additionally, the convertible dosimeter reader can be used to read multiple different types of dosimeter elements contained on a single dosimeter badge, thereby allowing a badge to be read in a multi-stage reading operation in a single dosimeter reader which is preferably automated. The optical laser converter includes a converter block assembly which defines multiple optical pathways therethrough. The convert block assembly is movable between different positions to align the different optical pathways with an incoming laser beam.
    Type: Grant
    Filed: June 26, 1989
    Date of Patent: August 20, 1991
    Assignee: International Sensor Technology, Inc.
    Inventors: Wolfgang Tetzlaff, James W. Hoelscher, Peter F. Braunlich, Carl D. Bloomsburg
  • Patent number: 5015855
    Abstract: Dosimeter reading methods and apparatus particularly useful in the measurement of heavy particle radiation dose exposure, such as from neutrons, protons, and alpha particles among others. The methods include exposing a dosimeter to a radiation environment to be measured. The dosimeter is thereafter stimulated, such as by a laser beam, to cause emission discharges from the dosimeter which are variable and indicative of the amount of ionizing radiation to which the element was exposed. Dosimeter elements which experienced an ionizing event from a heavy particle have higher levels of energy stored therein and produce higher luminescent or other emissions, thus characterizing that element or sample area as an eventful sample area. The number, portion or other measure of the eventful sample areas provides a basis for determining the level of radiation exposure due to the heavy particle or other discernable type of ionizing event.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: May 14, 1991
    Assignee: International Sensor Technology, Inc.
    Inventors: Peter F. Braunlich, Wolfgang Tetzlaff
  • Patent number: 4999504
    Abstract: Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via transmissive fiber which also preferably serves to return the emission from the luminescent sensor.
    Type: Grant
    Filed: May 31, 1989
    Date of Patent: March 12, 1991
    Assignee: International Sensor Technology, Inc.
    Inventors: Peter F. Braunlich, Wolfgang Tetzlaff, Joel E. Hegland, Scott C. Jones
  • Patent number: 4906848
    Abstract: Apparatuses and methods for rapidly reading phosphors to determine the amount of energy stored therein. The stored energy is interpreted as a measure of the total exposure of the phosphor to ionizing radiation. The phosphor reading apparatus uses a laser to generate a laser beam. The laser beam power level is monitored by a laser power detector and controlled to maintain the power level at a desired value or values which can vary with time. A shutter or other laser beam interruption means is used to control exposure of the phosphor to the laser beam. The laser beam can be equalized using an optical equalizer so that the laser beam has an approximately uniform power density across the beam. The phosphor emits a visible or otherwise detectable emission which is measured as an indication of the radiation exposure of the phosphors. Also disclosed are preferred signal processing and control circuits including one system using a digital computer.
    Type: Grant
    Filed: June 12, 1989
    Date of Patent: March 6, 1990
    Assignee: International Sensor Technology, Inc.
    Inventors: Peter F. Braunlich, Wolfgang Tetzlaff