Abstract:
A lamp was designed and constructed arranging number of coloured LEDs
to produce a monochromatic light beam comparable to low pressure Na
lamps with light intensity that are used in physical optics experiments. It
comprises compact closed casing with the power wire. The casing
comprises square opening (1.5cm x 1cm) in front side to get light beam
from the lamp. The power wire is extending 1.2 m with a two pin plug at the
end. The power is supplied to the lamp from AC 230V ma in power. The
lamp is compact and smaller in dimensions, 8cm x 6.5 cm x 4cm and is
equipped with a hanger to hang it to a required height. Also it can be kept
horizontally on a flat surface. The weight of the lamp is about 300 grams
and it produces monoch romatic light beam. The intensity of the beam varies
with distance away from the source point. The maximum of 140 Lux can be
achieved at the source point. The lamp can be used effectively as a
substitute for high cost monochromatic Na lamps currently used in optics
experiments. In addition to that it is low in cost, consumes less power and is
smaller in physical size with compared to conventional Na lamp.
