Eli5: why are blue lasers so cheap

[tuskiomi]

It seems like price/perfomance wise, blue laser beat red and green ones, always wondered this, but why?

 

[doubleone44]

High power blue laser diodes are used in projectors, so there is a pretty big market on them. Not so much for other colors. This makes them cheaper

 

[sinner]

higher commercial demand, easier to find, etc etc, moar fun for us laser heads.

 

[micheal rosen]

well, i understand why they are cheaper than green (DPSS is expensive, and direct diode green is relatively new) but i have no idea as to why diode red isn't as cheap. a 1W red is over 100$ even in the cheapest build you can make (well, for 635/638nm that is), and that's still pushing current diodes/diode technology! meanwhile 1W of blue is 85$ already built, and you can get lasers WAY beyond that for only a little more.

and the weirdest part is that red diodes have been around longer.

 

[gozert]

well, i understand why they are cheaper than green (DPSS is expensive, and direct diode green is relatively new) but i have no idea as to why diode red isn't as cheap. a 1W red is over 100$ even in the cheapest build you can make (well, for 635/638nm that is), and that's still pushing current diodes/diode technology! meanwhile 1W of blue is 85$ already built, and you can get lasers WAY beyond that for only a little more.

and the weirdest part is that red diodes have been around longer.

Like people above me already said, if there's not enough demand for a certain diode, then it will be produced less. And producing lower quantities results in overall higher costs. The thing with DPSS is that they require precise assembly and aligning. Apart from 532nm there really is not much demand for other wavelengths.

 

[micheal rosen]

if there's not enough demand for a certain diode, then it will be produced less.

yes but why is there more demand for blue? i thought that 405nm purple was used in blu-ray burners and readers, not blue, and thats probably a large source of demand. if blue is being produced for laser projectors, then why isn't red becoming cheaper or available in higher powers?

obviously, DPSS is expensive and i understand why, and diode green is new (new tech is always expensive), but what about red? why isn't red as cheap as blue. is it because of limitations of current diode technology or is it really that old "supply and demand" thing?

the thing i'm wondering about the most is what is blue being used in more than red and green?, and why in such high powers to facilitate its dropping in price.

 

[Encap]

High power blue laser diodes are used in projectors, so there is a pretty big market on them. Not so much for other colors. This makes them cheaper

Exactly.

yes but why is there more demand for blue? i thought that 405nm purple was used in blu-ray burners and readers, not blue, and thats probably a large source of demand. if blue is being produced for laser projectors, then why isn't red becoming cheaper or available in higher powers?

obviously, DPSS is expensive and i understand why, and diode green is new (new tech is always expensive), but what about red? why isn't red as cheap as blue. is it because of limitations of current diode technology or is it really that old "supply and demand" thing?

the thing i'm wondering about the most is what is blue being used in more than red and green?, and why in such high powers to facilitate its dropping in price.

See answer, above, in post # 2

Blue laser diodes in combination with a converter wheel, which converts part of the blue light into the two primary colors of red and green, are used as the light source for laser projectors. Example: One blue laser creates the blue light (obviously). The other blue laser hits a yellow phosphor, which is then split to create red and green (yellow being a mix of red and green). Another type --Sony 3LCD projectors --example: blue laser array is concentrated even further by an aspheric lens and directed at a spinning phosphor wheel that glows bright white. It is this phosphor that provides all the illumination for the screen. Light from the phosphor wheel is concentrated by a second aspheric
lens and directed toward the 3LCD panels.

 

[micheal rosen]

Exactly.



See answer, above, in post # 2

Blue laser diodes in combination with a converter wheel, which converts part of the blue light into the two primary colors of red and green, are used as the light source for laser projectors.

oh so laser projectors dont have red green and blue diodes, just a blue one? i thought they had a RGB thing going on in there. thank you for the explanation.

 

[hwang21]

Also- in making "white" light from a projector, more blue is needed than green or red. So it makes sense that the blue diodes have more powerful outputs

 

[blasterman]

638's have already dropped in price a lot. Consider what they cost at the 1watt level 5 years ago. It's just the demand for 445's is much higher, and production has caught up with demand. 638's will keep dropping price as large format video applications drive the market.

Same with green DPSS. although the curve will be a lot longer.

200mw 650's would cost a fortune if it weren't for the fact every desktop computer for years came with at least one or two.

 

[Laser Chick]

See the picture of the bank of blue laser diodes in this link.
http://laserpointerforums.com/f44/has-anyone-tried-laser-cannon-56063.html