Pure crystalline YAlO3 can be applied due to its high refractive index as a
novel material for optical elements within 240-1000 nm light transmission.
If used as front-windows for photon detectors and coated with a photocatho
de at its vacuum interface, it improves their light collection efficiency.
Its high refractive index increases the numerical aperture of lenses and he
nce their spatial resolving power. It matches favorably with the refractive
index of MgF2, which used as antireflection coating reduces the surface re
flectance close to zero. Doped with Ce3+-ions, YAlO3(Ce) can be readily use
d as scintillating front windows of vacuum-sealed photon detectors for ioni
zing radiation. (C) 2000 Elsevier Science B.V. All rights reserved.