Spectrometer no. 3215.30 is an optical instrument,
which can be used to determine the wavelength of
light as well as the index of refraction of solids and
liquids.
The instrument is supplied with the following
standard accessories:
- 1 ea. prism holder
- 1 ea. grating holder
The spectrometer consists in principle of a solid
base with a turntable, a prism table, a collimator and
a telescope.
The turntable
The turntable (2) is the major part of the instrument.
It is mounted with a robust bearing, and it can be
rotated around a vertical axis. It is provided with a
circular scale (7) marked from 0 to 360 degrees at
0.5 degree intervals. There is a vertical axle in the
center of the turntable which can rotate inde
-
pendently of the table. This axle extends beyond the
top of the table and is terminated in a fitting (22) to
which the prism table can be mounted. In addition
the vertical axle is provided with a pair of nonius
scales (8) which are concentric to the cirular scale.
The turntable is supplied with a dust cover (3) with
two windows for reading the two nonius scales
which permit a reading accuracy of 0.1 degrees.
The prism table
The prism table (6) consists of two metal discs,
which are held together with three spring-loaded
adjustment screws (24) placed at the apexes of an
equilateral triangle. A prism holder (25) or a grating
support (27) can be mounted on the uppermost disc.
The table is provided with an engraved marking at
the center to assist in the correct placement of the
prism.
The axle, which is to be mounted in the fitting (22) on
the vertical axle, is attached to the lowermost disc.
The prism table can be locked in relation to the two
nonius scales by means of the long adjustment
screw (23) mounted in the fitting. The vertical axis
supporting the nonius scales and the turntable can
be locked by means of the adjustment screw, (20)
which is placed on the spectrometer support. When
the prism table and the nonius scales are locked,
they can be rotated slowly using the fine adjustment
knob (21) on the side of the spectrometer support.
Collimator
The collimator (5) consists of two concentric metal
tubes with an adjustable vertical slit (19) at one end,
and a convex lens (13) at the other.
The collimator is attached to a support which is fixed
to the supporting structure (1) of the instrument. The
collimator can be adjusted around a horizontal axis
(10) by means of two adjustment screws (17) which
are mounted below the collimator tube. The distan-
ce between the slit and the lens can be adjusted by
means of the focussing knob (18) on the side of the
collimator.
The Telescope
The telescope (4) which is attached to the arm of the
prism table is an astronomical telescope with a
cross-hair sighting device (15) and a Ramsden
eyepiece (14) positioned at one end of two concen-
tric tubes. There is a convex lens at one end. The
telescope can be tipped up and down around a
horizontal axis by mewans of two adjustment
screws (9) beneath the telescope tube. The tele -
scope can be locked in position by means of an
adjustment knob located under the prism table arm
(16). When the telescope is locked, it can be turned
slowly by means of the fine adjustment screw (12)
located on the side of the telescope arm. The
position of the telescope can be read off the main
scale by means of two nonius-scales. The telescope
can be focussed by means of the focussing knob
(11) on the right hand side of the telescope.
Preparation of the Spectrometer
First adjust the ocular (14) so that the cross hairs can
be clearly seen. No direct the telescope at a distant
vertical object, and focus sharply using the the ad -
justment knob (11). Rotate the cross hair unit so that
User manual for Spectrometer no. 3215.30
14.12.10
Ae 3215.30
A/S Søren Frederiksen, Ølgod
Tel. +45 7524 4966
Viaduktvej 35 · DK-6870 Ølgod
Fax +45 7524 6282
www.frederiksen.eu
®
