3B Scientific Teltron Optical Equivalent to Debye-Scherrer Interference User Manual
Page 2
A TELTRON Product from UK3B Scientific Ltd. ▪ Suite 1 Formal House, Oldmixon Crescent ▪ Weston-super-Mare
Somerset BS24 9AY ▪ Tel 0044 (0)1934 425333 ▪ Fax 0044 (0)1934 425334 ▪ e-mail [email protected]
Technical amendments are possible
© Copyright 2012 3B Scientific GmbH
3. Operation
3.1 Set-up
To perform the experiment the following equip-
ment is also required:
1 optical lamp
1003188
1 transformer 12 V (@230 V)
1000593
or
1 transformer 12 V (@115 V)
1006780
1 tube holder D
1008507
1 convex lens,f = 100 mm
1003023
1 object holder on stem
1000855
1 projection screen
1000608
1 tripod base
1002835
3 barrel foot
1001046
•
Set up the experiment as in Fig. 1.
•
Insert the aluminium disc into the tube
holder from the rear.
•
Mount the pinhole aperture slide on the ob-
ject holder and position it close to the lamp.
•
Adjust the height of the components so that
the light beam passes through the cross lat-
tice.
3.2 Procedure
•
Perform the experiment using white light in a
darkened room
•
Vary the distance between the pinhole aper-
ture and the lens until the diffraction pattern
is visible on the screen.
•
First study the diffraction pattern when the
grid is not moving.
The diffraction pattern is similar to that of an
electron beam diffracted through a polycrystal-
line graphite lattice where all atoms are equally
spaced.
•
Then rotate the disc rapidly.
The rotating grid simulates diffraction of an elec-
tron beam at a graphite lattice with a more or
less random distribution of atoms.
The way that the diffraction pattern depends on
the wavelength can easily be demonstrated with
the help of coloured filters. The diameter of the
diffraction rings gets smaller as the wavelength
decreases from red to green.
•
Hold the colour filters close to the pinhole
aperture.
1
2
3
Fig. 1 Experiment set-up, 1 pinhole aperture slide, 2 lens, 3 aluminium disc