213results about "Chemical dosimeters" patented technology

A method of fabricating an apparatus for an enhanced imaging sensor consisting of pixellated micro columnar scintillation film material for x-ray imaging comprising a scintillation substrate and a micro columnar scintillation film material in contact with the scintillation substrate. The micro columnar scintillation film material is formed from a doped scintillator material. According to the invention, the micro columnar scintillation film material is subdivided into arrays of optically independent pixels having interpixel gaps between the optically independent pixels. These optically independent pixels channel detectable light to a detector element thereby reducing optical crosstalk between the pixels providing for an X-ray converter capable of increasing efficiency without the associated loss of spatial resolution. The interpixel gaps are further filled with a dielectric and or reflective material to substantially reduce optical crosstalk and enhance light collection efficiency.

A general purpose high accuracy dosimeter reader, 80, for determination of a treatment condition, based on comparison of an image of treated dosimeter, 111, with a series of images of pre-treated dosimeter, 114, is disclosed. A dosimeter undergoes noticeable changes, such as a color change upon treatment with certain materials, such as toxic gases and processes, such as ionizing radiation and sterilization is pre-treated. The dosimeter is imaged with an imaging device, 115, such as charge-coupled device camera and images of the dosimeter or the changes, e.g., color change, are stored in an information storage device, 118. In order to determine the treatment condition, the treatment dosimeter is imaged and the image is compared with the series of pre-treated images of the dosimeter using software. The closest match of the treated dosimeter with the pre-treated and pre-imaged dosimeter would indicate the treatment conditions. The process and device can be used for almost any indicating device, process and treatment.

A radiation dosimeter system and method for estimating a deposited radiation dose to an object involves locating at least one radiation dosimeter at the object. The radiation dosimeter includes a radiation sensitive medium having an optical property that changes due to the deposited radiation dose. An optical interrogation signal is provided to the radiation dosimeter via an enclosed optical path for interacting with the radiation sensitive medium. During irradiation, the optical interrogation signal is transformed into an optical information signal that encodes an ionizing radiation induced change in the optical property of the radiation sensitive medium. The radiation dosimeter system then processes the optical information signal for estimating the deposited radiation dose.

Described is a multi-sensor radiation dosimeter system with (1) a self-indicating, instant radiation sensor and (2) a conventional radiation sensor for monitoring high energy radiations, such as X-ray, electrons and neutrons. Conventional radiation sensors, such as X-ray film, TLD (Thermoluminescence Dosimeters), RLG (Radioluminescence Glass) and OSL (Optically Simulated Luminescence), are highly sensitive but are not instant. In the event of a dirty bomb, nuclear detonation or a radiological accident, one needs to know the exposure instantly so proper precautions can be taken and medical treatment, if required, can be given to the victim. If a self-indicating instant sensor is one of the sensors, one would know the dose instantly, and dose can be determined with higher accuracy than by the traditional methods. This type of device offers the best of both technologies.

The present invention relates to devices, systems, and methods for determination of ionizing radiation. In some embodiments, the devices comprise nanocomposite materials containing nanostructures (e.g., carbon nanotubes) dispersed in radiation sensitive polymers. In some cases, the device may include a conductive pathway that may be affected upon exposure to ionizing radiation. Embodiments described herein may provide inexpensive, large area, low power, and highly sensitive radiation detection materials / devices.

The present invention relates to an ultraviolet radiation detector in general and more specifically to a solar blind ultraviolet radiation detector; that is, a detector insensitive to the radiation of sunlight reaching the earth's surface but sensitive to UVC wavelengths in the spectrum, defined as the interval 200 nm-280 nm. The solar blind detector is base on the use of photochromic compounds in conjunction with ultraviolet wavelength-selective chemical blocks and their incorporation into optically clear polymer matrices. The photochromic compound is selected from the group comprising spiropyran molecules spirooxazine molecules and chromene derivatives. Applications for such device are as numerous as the sources of UVC radiation. An obvious use for such Solar Blind UVC detector is monitoring the output of UVC sources used in the decontamination of water and air (water treatment and air purification) and for sterilization of medical instruments.

The present invention provides an authentication system and methodology in which an authenticating agent is used as a product marker to help determine the source of products. The authenticating agent includes a substance that forms free radicals upon irradiation. The spectroscopic response of the agent when in the free radical state provides a characteristic "fingerprint" associated with genuine goods, but lacking in other goods. The goods incorporating the marker may be readily identified and / or distinguished from similar goods originating from another source. Furthermore, when not in the activated state, the authenticating agent typically is not detectable, thus providing the advantage of not being readily identifiable by counterfeiters.

An article of manufacture comprising a radiation sensitive material, and a measuring scale that is part of the radiation sensitive material. A method of measuring at least one parameter relating to an irradiated material is also described. A radiation sensitive material including a measuring scale is exposed to radiation and at least one parameter relating to one or more exposed areas of the material is measured by reference to the measuring scale on the material.

A night vision coloring system may color a scene by extracting the spectral signature of each area in a scene and matching the extracted signature with a predetermined database signature and associated color. The system may comprise a temporal or spatial filtering element that may typically allow the capturing of an image reflection through a plurality of spectral bands, thereby extracting the spectral signature of each area in the image. The color associated with the matched database signature may be used to color each area comprising the image.

A thermoplastic composition comprises a polycarbonate that is not aryl carboxylate end-capped, and an aryl carboxylate end-capped polycarbonate of formula:Ar1-C(O)—O-(-L-)m-O—C(O)-A1wherein each Ar1 is independently an aryl group, -(-L-)m- is a polycarbonate linking group with m units of linking unit L, and m is at least one; wherein the aryl carboxylate end-capped polycarbonate has aryl carboxylate end groups present in the thermoplastic composition in an amount of 0.01 to 500 mmol / Kg based on the combined weights of the polycarbonate that is not aryl carboxylate end-capped, and the aryl carboxylate end-capped polycarbonate, and wherein a molded article having a thickness of 3.2±0.12 millimeters and consisting of the aryl carboxylate end-capped polycarbonate, the polycarbonate, and less than or equal to 1.0 percent total weight of aliphatic diol, a mold-release agent, and an antioxidant has, after exposure to a total gamma radiation dose of 81 kGy and when measured according to ASTM D1925-70, an increase in yellowness index (dYI) of less than or equal to 24.5, when compared to the unexposed molded article. A method for preparing the aryl carboxylate end-capped polycarbonate that is not aryl carboxylate end-capped, and thermoplastic composition, an article prepared from the thermoplastic composition, are also disclosed.

A liquid scintillator detector for three-dimensional dosimetric measurement of a radiation beam is provided wherein a volumetric phantom liquid scintillator is exposed to the radiation beam to produce light that is captured by the cameras that provide a three-dimensional image of the beam.

A disposable device for monitoring exposure to ultraviolet radiation (UVR) over a single period of time and a cumulative period of time. The device includes a base upon which is applied a UVR sensitive material that irreversibly changes after exposure to UVR. A protective covering is applied over the UVR sensitive material and includes segments that are individually removable to reveal a portion of the UVR sensitive material thereunder. A UVR exposure scale and first and second keys are provided on the base. A first segment of the covering is removed and the base is placed in an appropriate location. After a period of time, the change in the UVR sensitive material is compared to the scale and first key to determine if the level of exposure is safe for that time period. The procedure may be repeated over a number of time periods with a new segment of the protective covering being removed for each time period. The cumulative UVR exposure is determined by comparing the change in the first time period's UVR sensitive material to the scale and a second key associated therewith.

Described is a self-indicating instant radiation dosimeter (1001) for monitoring high energy radiations, such as X-ray. The dosimeter contains a radiation sensitive, color changing, indicating composition (10), e.g., a diacetylene (R—C≡C—C≡C—R′, where R and R′ are substituents groups) or a radiochromic dye, a polymeric binder (20) and optionally a shelf life extender (50) or an activator (40). The radiation sensitive composition (10) changes color instantly when exposed to high energy radiation. The dose is estimated by comparing the color with a color reference chart or more accurately with a spectrophotometer or an optical densitometer. The radiation sensitive composition (10) is protected from low energy radiation such as UV light, by a layer of low energy absorbing materials, such as UV absorbers.

Provided is a flat panel detector which prevents aging deterioration of characteristics of a phosphor layer, protects the phosphor layer from chemical alteration or physical impact, and maintains a stable contact state between a scintillator panel and a flat light receiving element. Disclosed is a flat panel detector comprising a scintillator panel comprising a scintillator provided with a phosphor layer on a substrate and a protective layer covering the phosphor surface of the scintillator, and the scintillator panel being placed on the surface of a flat light receiving element comprising plural picture elements which are two-dimensionally arranged, wherein a re-releasable adhesive layer is provided on the protective layer surface.

A smartcard or other media detects the presence of chemical, biological, radiation, and / or explosive (CBRE) compounds or other items of interest on individuals handling the smartcard or other media. The exposure is stored such that, when the card is presented to a reader, the detection data is transmitted to the reader for appropriate processing by the system. In one embodiment, this invention provides a detection methodology which captures the fact that the holder of the detection device has been in contact with an item of interest without external power. The detector card is then able to alert appropriate authorities of that exposure when the device is presented to a reader in the normal course of the holder's business.

A system and method for real-time measurement of curing energy delivered to a simulated dental restoration from a source of curing energy. The system comprises a detector and a display. The detector measures at a location within the simulated dental restoration the amount of curing energy delivered by the curing energy source. The display displays the measured amount of curing energy in real-time. The system also comprises a temperature detector to measure temperature changes in the oral tissues during curing (teeth and gums). The system also comprises a video camera to record the operator's curing technique.

Personal radiation detection devices, methods of obtaining radiation exposure data, and networks of personal radiation devices. The detection devices may include passive devices and active devices. The passive detection devices may have the same form factor as credit cards or be included in common types of credit card form factor sized cards. The active devices may be incorporated into common and widely distributed host devices.

To detect an irradiated radiation efficiently, so that the dose can be measured with high sensitivity. A photochromic material comprising an illuminant(s) which emits a light when irradiated with a radiation and a diarylethene photochromic compound(s) having a specific structure, and a color dose meter employing it.

Methods are provided for the detection of an analyte in a sample using wavelength modulated differential photothermal radiometry with enhanced sensitivity. A wavelength modulated differential photothermal radiometry system, comprising two optical modulated beams, where each beam experiences different absorption by the analyte, is calibrated by controlling the relative phase difference between the modulated beams so that individual photothermal signals corresponding to each modulated beam are 180° out of phase, corresponding to peak sensitivity to analyte concentration. The system may be further calibrated by varying the relative intensities of the two modulated beams and measuring standards containing known analyte concentration in order to determine an optimal relative intensity for a given concentration range of interest.

Devices and methods for the characterization of areas of radiation in contaminated rooms are provided. One such device is a collimator with a collimator shield for reducing noise when measuring radiation. The determination system uses a radiation detector comprising a plurality of overlapping layers of radiation sensitive film interspersed with adjacent layers of an attenuator material. The resulting sandwich of the stacked film layers and attenuator layers provides a useful detector. The detector can be used within a radiation detector apparatus having a collimator to enable a 360 degree field of view of radiation sources within a room or enclosed environment.

Methods and apparatus relating to the imaging of biological samples are provided. More particularly, they relate to the detection of light emanating from fluorescent species present in a sample in order to study the structure and dynamics of such a sample. Such a method of analysis comprises irradiating the sample with a pulse of excitation energy causing fluorescent species in the sample to fluoresce; detecting light emanating from the sample during a predetermined period of time after the pulse; generating and storing data recording at least the wavelength of the detected light against time; and analysing the data with reference to the respective lifetimes of the fluorescent species to detect the presence of the respective emissions from three or more different fluorescent species which emit light simultaneously during at least part of said predetermined period, which are indistinguishable from each other on the basis of their wavelength or lifetime alone.