MIR middle infrared; 2.5-50 µm
MS magnetron sputtering
NA numerical aperture
N-BK7 borosilicate crown glass
NIR near infrared; 780-2500 nm
NP... nonpolarizing ...
Ø diameter
OAP off axis parabola
OC output coupler
OD optical density
OPO optical parametric oscillator
ord. ordinary
pl plano
ppm parts per million
p-pol p-polarized light
PR partial reflector
PV peak to valley
QWOT quarter wave optical thickness
QWS quarter wave stack
R     reflectance
RF radio frequency
Rp p-polarization reflectance
Rs s-polarization reflectance
rms root mean square
ROC radius of curvature
SP short (wave) pass
s-pol s-polarized light
t     thickness
tc  center thickness
TE thermal evaporation
TFP thin film polarizer
TIR total internal reflection
TIS total integrated scattering
Tp p-polarization transmittance
Ts s-polarization transmittance
TSB total back scattering
UHV ultra-high vacuum
u-pol unpolarized light  u = (s+p)/2
US  ultrasonic
UV ultraviolet; 180-379 nm
UV-FS Fused Silica with high UV-transmittance
VA variable attenuator
VIS visible light; 380-779 nm
VLT visible light transmission
VUV vacuum ultraviolet; 120-179 nm