Resistance to Xray Browning (Turning brown after long-term use)
Absorb scattering light generated by phosphor
rhFOP are made from material that can absorb Xray energy. It will protect the sensor from the excessive Xray leak from phosphor (scintillator). Which will improve lifetime of sensor, and also increase the SNR of the system.
*rhFOP are cerium doped by default
CsI(Tl) has a primarily columnar crystal structure as seen in Figure below) and, depending on the conditions, approximately 83% is reflected within the columnar crystal.
For this reason, light is guided into the crystal wall and a certain fraction is guided into the photodiode direction. These are referred to as structured scintillators. CsI (Tl) scintillator can be deposited on substrates such as glass, which is then flipped and adhered to the photodiode. It can also be deposited directly on the photodiode or deposited on the fiber optic plate. (See Below)
While light travelling within the phosphor, the light will spread—the amount of diffusion being proportional to the path length required to escape the phosphor. X rays interacting close to the photodetector give rise to a sharper (less blurred) optical signal than those which interact more distantly. The paths of most optical quanta will be shortest if the photodetector is placed on the x-ray entrance side of the phosphor.
Fiber optic plate can and directly coupling to CCD/CMOS and absorb scattering light that may blur the image. Which will improve the SNR of the system.
Diameter of a fiber strand / Distance between fiber centering
The numerical aperture, or NA, defines the angle of acceptance—beyond which light is lost out the sides of the fiber. The greater the NA of the fiber, the better the light transmission of the fiber.
The larger the N·A is, the
greater of luminous flux will be entering the fiber-optic image element
A detail resolution capability of the
optical system to the transferred image
The higher the resolution is,
the stronger the ability of distinguish image details will be.
In addition to the mono fiber elements, a second fiber is used in the construction of the multi fiber. Extra-mural absorption (EMA)fibers are special black absorbing fibers, inserted between (or in place of) mono fibers, which will absorb stray (scat-tered) light in the fiber optic material.
The transmitting qlass in a fiber optic wave guide. The core has a higher index of refraction than the cladding.
The outer layer of glass in a fiber optic wave quide. The claddinc has a lower index of refractior than the core.