Difference between revisions of "OSL Reader"
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| − | The OSL reader is a | + | The OSL reader is an closed blue box of dimensions x by y by z. On the left side of the front face is the drawer in which an OSL in a holder is inserted. Once the drawer is shut, the black knob on the front is turned from H/P to E1, which activates the LED inside and allows the photo multiplier tube to count the hits through the crystal. |
| − | The | + | -> Picture of OSL reader |
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| + | The MicroStar OSL reader manufactured by Landauer is used to analyze the nanodot OSLs. By inserting an OSL into the reader, the crystal structure is exposed to an LED and a photomultiplier tube on the opposing side is used to measure the opacity. The PMT counts are then used in the Cs-137 calibration to give a calculated dose in milliRad (mRad). | ||
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| + | The OSL reader calculates the dose from the PMT counts, OSL sensitivity, and calibration factor. The equation used for this calculation is: | ||
<math> \frac{PMT Counts}{(Calibration\ factor) (Sensitivity)} = Dose\ (mRad) </math> | <math> \frac{PMT Counts}{(Calibration\ factor) (Sensitivity)} = Dose\ (mRad) </math> | ||
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| + | The OSL reader has software capable of calibrating the reader, which in turn creates a low and high dose calibration. These different calibrations give separate calibration factors. To create the calibrations within the software, Landauer supplies pre-dosed OSLs, of 5 different values. Due to uncertainty in exposure between dosing and usage, a custom calibration should be used to reduce error in succeeding measurements. | ||
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The low dose (10000 mRad>) calibration factor is 9.496494 as of 11/1/2017 | The low dose (10000 mRad>) calibration factor is 9.496494 as of 11/1/2017 | ||
The high dose (>10000 mRad) calibration factor is 0.6806084 as of 11/1/2017 | The high dose (>10000 mRad) calibration factor is 0.6806084 as of 11/1/2017 | ||
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According to this link https://www.nagase-landauer.co.jp/english/inlight/microstar.html, readout is 13 sec for OSLs in the microstar I. | According to this link https://www.nagase-landauer.co.jp/english/inlight/microstar.html, readout is 13 sec for OSLs in the microstar I. | ||
Technical specs https://www.nagase-landauer.co.jp/english/inlight/pdf/Readers/microstarreader.pdf | Technical specs https://www.nagase-landauer.co.jp/english/inlight/pdf/Readers/microstarreader.pdf | ||
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Revision as of 20:17, 8 June 2018
The OSL reader is an closed blue box of dimensions x by y by z. On the left side of the front face is the drawer in which an OSL in a holder is inserted. Once the drawer is shut, the black knob on the front is turned from H/P to E1, which activates the LED inside and allows the photo multiplier tube to count the hits through the crystal.
-> Picture of OSL reader
-> Picture of OSL holder
The MicroStar OSL reader manufactured by Landauer is used to analyze the nanodot OSLs. By inserting an OSL into the reader, the crystal structure is exposed to an LED and a photomultiplier tube on the opposing side is used to measure the opacity. The PMT counts are then used in the Cs-137 calibration to give a calculated dose in milliRad (mRad).
The OSL reader calculates the dose from the PMT counts, OSL sensitivity, and calibration factor. The equation used for this calculation is:
The OSL reader has software capable of calibrating the reader, which in turn creates a low and high dose calibration. These different calibrations give separate calibration factors. To create the calibrations within the software, Landauer supplies pre-dosed OSLs, of 5 different values. Due to uncertainty in exposure between dosing and usage, a custom calibration should be used to reduce error in succeeding measurements.
The low dose (10000 mRad>) calibration factor is 9.496494 as of 11/1/2017
The high dose (>10000 mRad) calibration factor is 0.6806084 as of 11/1/2017
According to this link https://www.nagase-landauer.co.jp/english/inlight/microstar.html, readout is 13 sec for OSLs in the microstar I.
Technical specs https://www.nagase-landauer.co.jp/english/inlight/pdf/Readers/microstarreader.pdf