Gendex DenOptix QST, Operator'S And Service Manual

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User and Service Manual
Doc # M010-004WWE July 2005
Gendex DenOptix® QST
In essence, they act as an “energy trap,” storing X-ray energy. The amount of energy stored
is directly proportional to the amount of X-ray energy the crystal was exposed to.
The DenOptix QST scanner further excites the phosphor crystals to an unstable state by
exposing them to a red laser. The phosphor crystals then release a blue light and return to
their stable ground state. The DenOptix QST scanner reads this blue light and, with the imag-
ing software, produces an image.
This process does not completely erase the imaging plate. Some crystals remain as “energy
traps.” This information can be erased by exposing the imaging plate to light. A few seconds
of low levels of light will usually not effect the image quality. Once erased, the imaging plate
can be re-exposed and the process can begin again. With proper handling, DenOptix QST
Imaging Plates can be continually reused.
Without light, storage phosphor imaging would not work. The red light from the laser
scanner excites the exposed imaging plates, causing them to emit blue light. After your
computer interprets the blue light and changes it into a digital image, light is used to erase
the residual information from the imaging plate.
Between X-ray exposure and scanning, however, one must be careful handling the imaging
plates. An imaging plate should never be removed from its protective barrier and exposed to
a strong source of light. This act would erase the latent image from the plate. Therefore, you
must load imaging plates onto the carousel under controlled lighting conditions. The recom-
mendations below have been developed to ensure that you obtain excellent image quality.
Recommendations on lighting conditions for loading carousels
Fluorescent lights
If loading can be accomplished in less than 60 seconds, the fluorescent lighting in the area
should not exceed 20 lux. If loading will take longer than 60 seconds, the room conditions
need to be darker. At 10 lux, the operator has about 5 minutes to accomplish loading.
Incandescent lighting
Incandescent lighting is not as efficient as fluorescent lighting at fading imaging plates. We
recommend lighting conditions of around 20 lux. Under incandescent lighting, however, you
have about 2 minutes to complete the loading process. If it takes longer than 2 minutes,
decrease the amount of light to 10 lux.
11.2 Appendix B: Lighting conditions for handling or erasing
imaging plates