Why switch from TLD to OSL?

Discover the OSL LANDAUER dosimetry offer. It covers the entire manufacturing and processing of dosimeters with a wide range of equipment such as: badges, readers, zeroing devices, software, etc.

OSL benefits

A complete lab solution in a compact size
A full range of dosimeters adapted to measure H_p(10), H*(10), H_p(3) and H_p(0.07)
Scalability from 1 to 700 InLight dosimeters for one process
No heating parameters to control
No gas supply
Fast reader throughput of 300 dosimeters / hour
Quality, simply and reliability
Remote diagnostic and maintenance
Dose assessment algorithm embedded

Learn more about OSL Technology

	OSL	TLD
Dose Deposition	Electron/hole capture at site of dosimetric traps in crystalline structure	Electron/hole capture at site of dosimetric traps in crystalline structure
Readout Mechanism	Optically-Stimulated Luminescence	Thermally-Stimulated Luminescence
Precision	Very good. Stable sensitivity	Very good*. Sensitivity changes with heating and annealing. Irradiator required
Accuracy	Very good to Excellent	Poor to good*
Readout speed	≈ 1 second	≈ 10 seconds
Re-read capability	YES	NO, single-read only
Operational overhead (man-hours, equipment)	Low (stable sensitivity, no nitrogen, no heating…)	High (need to source pure nitrogen, frequent maintenance) Replacement and management of Irradiator radioactive source
Mechanical resistance	Thin PET film resistant to crushing	Sensitive to crushing TLD crystal may come back broken altering the sensitivity
Influence of neutron dose	No influence	Under high neutron dose, photon dose reported will be over estimated

* Requires very stringent procedural controls to achieve good results.

Which solutions for your OSL lab?

OSLR readers OSLR

Three versions are proposed to read INLIGHT dosimeters using LANDAUER OSL technology.

OSLR readers perform both reading and annealing process with higher throughput making it quick and easy to process results. The readers OSLR 1, 50, OSLR 250 and OSLR 700 adapt to the number of monitored participants in your organization. The readers can easily be upgraded to a higher loader capacity to accommodate evolving needs.

OSLR is upgraded to read the new ONYX OSL ring and TOPAZ OSL lens of eye dosimeters which use the new generation of OSL sensor: MP7 sensor.

Learn more about our lab dosimetry equipment

OSL: the measure of luminescence

OSL dots on INLIGHT® component — OSL dots on INLIGHT^® component

Within a number of materials, the electrons and holes produced during radiation exposure can become trapped at crystal defects. The trap remains until they are stimulated giving rise to optical emission. The intensity of the optical emission is a function of the radiation exposure and the method/intensity of the stimulation. If the trapped charges are excited by thermal stimulation (thermoluminescence) then most of them are released and any record of the radiation exposure is lost. However, if the trapped charges are optically stimulated, only a small fraction of the trapped charge is released. The process is optimised by the frequency and duration of the stimulating light pulses, the characteristics of the photomultiplier used to detect the emitted light, and the material used as the OSL detector.

During readout, only a small fraction of the trapped charges are released. Thus, much of the trapped charge is retained following stimulation and may be released in subsequent stimulations. This enables INLIGHT dosemeters to be read out many times without significant loss of signal.

Al₂O₃:C, a material manufactured according to LANDAUER’ specifications

LANDAUER use aluminium oxide doped with carbon (Al₂O₃:C). It is produced at the LANDAUER Crystal Growth Facility in Stillwater, USA. Al₂O₃:C (corundum or sapphire) is used primarily because of its high sensitivity to radiation, 40 – 60 times that of LiF (TLD-100). It has a principal emission peak at 410 – 420 nm (blue). It also has excellent properties for radiation dosimetry, including linear response up to 50 Gy. Al₂O₃:C powder is obtained by grinding crystals and sifting the powder to the desired size range. This powder is mixed with a polyester binder and coated onto a roll of polystyrene film. The aluminium oxide layer is approximately 0.2 mm thick sandwiched between polyester foils 0.03 mm thick (top) and 0.1 mm thick (bottom).

Each reel of detector material received by LANDAUER is assessed by stringent quality assurance testing. The sensitivity of the material is printed on the top of the detector strip.