Zeiss TIRF 3, Руководство по эксплуатации

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OPERATION
Carl Zeiss Calibration of the Angle Using the Motorized Slider Laser TIRF Laser TIRF 3
84 423683-7144-001 02/2014
4.8.4 Determining the Critical Angle
The offset of the deflection can be determined using the actual sample. The angle is moved into the TIRF
position on both sides of the pupil using a software calibration routine. Once the critical angle is reached,
an exponential fall of the mean grey-scale value can be observed in the rear objective pupil (cf. the three
example images to the left). The inversion points of the grey-scale value curve at
1 g
α
and
2 g
α
mark the
critical angle in the specimen.
4.8.5 Determination of the Refractive Index of the Specimen
At the critical angle the equations are reduced
1
2
1
) sin(
n
n
=
α
and
1
0
64 . 1 015 . 2
) sin(
xn x
U U
−
=
α
to
2
n
=
64 . 1 015 . 2
0
x
U U
−
n
2
is the refractive index of the medium!