First there was RED lasers ( 630 to 680nm ) and these reduced in price when manufacturing ramped up for inclusion of red diodes in just about every CD , DVD player , burner and portable and car stereo on earth , this made selling of a red diode laser ( or laser pointer pen ) at cheap prices possible.

In manufacturing terms laser pointers or hand portable lasers are very small volumes so any laser product really needs the diodes to be manufactured for other products to make setting up factories etc viable ?

Next along came green lasers (532nm) around 2004 , prices were really high at first for green lasers ( and green pointers and pens ) sometiimes in excess of Ł1000 and sales were poor , but slowly volumes built and prices reduced as this is the best colour for lasers in terms of visabilty , sadly some retailers glamourised these products and sold at very high power levels , mass markteing of green lasers as prices reduced has caused huge problems with aircraft targetting and general abuse

Next was yellow lasers (593.5nm) , gorgeous colour and really attractive to look at although i think it could more be classed as orange than true yellow , prices have always remained as as thee is virtually no other market for yellow lasers , manufacturing has never increased volumes and yellow lasers are currently the most rare and exclusive colour , very recently in 2010 Lasers that are mmm MORE yellow , 589nm have entered the market , but currently again very expensive typically in excess of Ł500

BLUE : 405nm , 445nm and 473nm

It wasnt that long ago that it was said blue lasers were impossible to make then a japanese scientist discovered how to make blue laser light by accident, while trying to create blue LEDs. This was very exciting for the industry as the shorter wavelentgh was always going to be very useful for storage of bulk data on DVDs .... hence Blu Ray ! !

The first blue laser pointers to hit the market were 473nm , over Ł1000 and a truely stunning laser light to look at and these were only able to be manufactured as spare diodes became available from production of miltary storage storage products who were taking advantage of this shorter wavelentgh , however the military quickly moved onto even shorter wavelentghs so there no mass production of 473nm diodes , so prices of these in laser pointer or hand portable form are likely to remain high and on par with yellow lasers.

Then a bit of excitement , as mass market products such as DVD players / burners started being produced by the millions ( Blu Ray Products ) which meant loads of 405nm diodes available to be used in hand portable and laser pointers and laser pens , but in reality 405 is slightly fuzzy , slightly hazy and purple and not really that great or that useful so it has remained a hobbyist and specialist use laser

Now along has came 445nm Blue diodes ( 2010 ) being manufactured for use in display projectors such as casio XJA140 .... the incredibly exciting thing about these is the prices ! In early 2010 try and buy say 1000mW of 445nm and it would cost you Ł2500.... now people are paying Ł800 for a projector and literally ripping them a part as the unit contains 24 one watt ( 1000mW ) Blue 445nm lasers ... some hobbyist have built incredibly powerful 1000mW blue laser pointers and people who build laser projectors are jumping for joy as blue was always the most expensive part of their RGB setup , now its the cheapest and most powerful componant literally in the space of a few months.

We have seen them all and 473nm is a kind of light blue colour , 445nm is best described as royal blue and 405nm as purple , its not likely you will see a 445nm laser pointer or hand portable soon as at the moment the units are simply too powerful for handheld laser pointers ( 1 watt of laser anything is simply crazy power , and very very dangerous to eyes and skin )

Interesting times though !