An RGB laser is that beam source that emits red, green
and blue lights in form of laser beams either as a
separate beam for each color or a combination of all the
three colors in one beam. Through the process of
additive color mixing which is achieved through
combination of these lights, a number of many other
lights can be obtained.
RGB lasers are being exploited as an alternative to arc
lamps sources (beamers). Although arc lamps have been
used for a long period as a source of beams particularly
because they are much cheaper, they suffer from
setbacks such as limited lifetime, high wall-plug
efficiency is impossible, poor image quality as a result of
poor spatial coherence and the fact that available color
space is not wide enough. For this reasons, the former is
becoming more popular RGB sources are much more
Beams from these sources are known to be coherent in
both wavelengths, both in time and space allowing for
inferences. If the change in phase properties is able to
take place at the same time over a long distance and at
the same period of time, then such waves will produce a
very clear image. It is possible to cancel such waves with
a similar with opposite phase.
These lasers are known to produce beams of the three
primary colors with very narrow optical bandwidth
making them close to the monochromatic light beams.
They are thus capable of producing very clear images on
mixing, the reason why they are getting more
application like in cathode tube displays, color printers
and lamp-based beamers.
RGB sources however suffer from a major setback given
that the power level that is emitted is usually of low
level. Most cinema projectors for instance require up to
10 W per color or even more. This level of power
sufficiency, maturity or even cost effectiveness is still
beyond the existing RGB scanners. When it comes to
beam quality, these machines have to operate with high
quality beams for them to perform effectively.
In situations where optical modulators is not practical as
a result of low-power miniature devices or for any other
reason, the RGB sources are fitted with power-
modulators for better signals. Using laser diodes in
particular helps achieve modulation bandwidth of tens
to hundreds of megahertz or even higher resolutions.
There are many methods of constructing RGB lasers.
Three lasers with each emitting a particular light of a
wanted color is for instance an approach that has been
used for long. These visible light beams are however
limited in performance as compared to those that are
The other method is the use of an infrared solid-state
laser where a single near-infrared laser generate a single
color that then undergoes through different stages of
nonlinear frequency conversion to produce the three
colored beams. There are many other schemes of
producing the desired wave lengths such as through
combination of parametric oscillators, some frequency
mixers and even frequency doublers in addition to other
Technological advancement is however set to
completely address the challenges in with an RGB laser.
Just like other forms of lasers, they are set to be used in
all other areas where there are need for lasers like in
hospital machines, cutting technology and in
entertainment industry among others.