| Optics >
Interference > Gratings |
DCS# 6D10.11 |
MULTIPLE SLIT
PATTERN
APPARATUS
| CAL sheet aka Cornell slitfilm
demonstrator |
202-21-B5 |
| laser |
202-21-B6 |
DESCRIPTION
Shine the laser through sets of
different numbers of slits on the plate to project interference
patterns on the screen.
Green (532 nm) and red (650
nm) laser pointers can be used to show the dependence of
diffraction angle on wavelength.
NOTES
The layout
of the Cornell plate is shown at the right.
Column 1: single slits of
different widths
Column 2: double slits of
constant width and variable spacing becoming double slits of
constant spacing and variable width, becoming single slit of
varying width.
Column 3: gratings with
various ratios of slit width to slit spacing
Column 4: gratings with
different numbers of slits, each with same slit width and
spacing.
Column 5: double slits of
different spacings.
Refer to this
image for slit widths and spacings.
Beside each element:
top digit = number of lines,
middle
digit = width in points before 8x reduction,
bottom
digit = spacing in points between lines
(one point
= 0.013837 inch = 0.3523 mm).
The
distance in millimeters between the slits is shown under the
patterns.
