Tellurite And Fluorotellurite Glasses For Active And Passive

6. Optical properties; MDO 167
sample for near monochromatic radiation over a range of wavelengths. The energy, E, of
the incident radiation is given by equation (6.1) [3].
E = hf
(6.1)
where h = Planck’s constant = 6.62608×10 -34 J.s and f = frequency of the incident
radiation. The wavelength, λ, of the radiation is given by equation (6.2) [3].
c
λ =
(6.2)
f
where c = the speed of light in a vacuum = 2.99792458×10 8 m.s -1 . Spectroscopists often
express the x-axis of spectra in wavenumbers, f ~ , which are usually measured in
reciprocal centimetres (cm -1 ). This is convenient, as wavenumbers are directly
proportional to energy. Equation (6.3) shows the relation between wavenumbers and
equation (6.1) and (6.2) [3].
~ f 1
f = = =
c λ
E
hc
Fig. (6.1) shows the setup of a typical dual beam absorption spectrometer [3].
(6.3)