Quad red arrangement

[laser_freak]

I'm currently in the process of building my quad red. I plan on knife edging both pairs of beams and then combining them with a PBS cube. However take a look at the picture below. Should I arrange like the first pattern or like the second pattern? All of the quad reds I have seen use the second pattern, but why not use the first pattern? Is there any disadvantage to it?

[andy_con]

neither...

if your using a cube then your final beam will only be two beams as your combining two sets

[laser_freak]

Ah, I completely forgot about that way of doing it. However then I'd have a oblong beam, but with a higher power density. Is there any way of then making that oblong beam more round again?

[andy_con]

Ah, I completely forgot about that way of doing it. However then I'd have a oblong beam, but with a higher power density. Is there any way of then making that oblong beam more round again?

not really as beams arent round they are oval.

heres an example.

using an open can diode and a 7020h lens you get a beam of 3mm wide by 5mm high.

so put two side by side and you get 6mm wide by 5mm high, so not far from a round beam.

measures ya beams at apeture and work out the best way to combine them

[laser_freak]

not really as beams arent round they are oval.

heres an example.

using an open can diode and a 7020h lens you get a beam of 3mm wide by 5mm high.

so put two side by side and you get 6mm wide by 5mm high, so not far from a round beam.

measures ya beams at apeture and work out the best way to combine them

Thanks for the help andy.
Can you help me understand the advantages of using certain lenses in different setups? For example, I've often read that you should use a different lens if you plan on using a telescope. Why?
Also, do you suggest using the 7020h lens for the quad I've described in my first post (knife edge + PBS, but no telescope)?

Thanks

[andy_con]

Thanks for the help andy.
Can you help me understand the advantages of using certain lenses in different setups? For example, I've often read that you should use a different lens if you plan on using a telescope. Why?
Also, do you suggest using the 7020h lens for the quad I've described in my first post (knife edge + PBS, but no telescope)?

Thanks

i cant anwser this for you, you need to anwser it.

what size scanner mirrors do you have and what beam will fit on them? no point having a big beam if you loose 30% off the mirrors.

you havent even said what diodes you are using?

i suspect a 6mm by 5mm beam will be to big for your scanner mirrors so you will need either telescopics of different lens

[LaNeK779]

something with a short focal length should be fine with 6mm mirrors, knife adge and pbs

something like the 405-g-2- people use for the 445. could this lens wrk for red, too?

[laser_freak]

My galvo mirrors are 6mm x 10mm. I'm using 2 LOC diodes and 2 HL6385DG 150mw 642nm diodes.

I know the basics of choosing a lens; a large focal length will output a large beam with a small divergence while a small FL will output a small initial beam with a large divergence.

However, I can't find any specifications for the lens27, but am I correct in assuming that they are a short FL lens?

[taggalucci]

Hi there,

I'm playing around with combining reds as well, and have some info of use...

HL6385DG 150mw 642nm diodes

I believe these perform very similar to the LPC-815 diodes.

However, I can't find any specifications for the lens27, but am I correct in assuming that they are a short FL lens?

M9x0.5, f = 3.6 mm, 1 lens glass, NA=0.45, ARC

[badger1666]

There are some super duper lens on the way keep an eye on the forum over the next few weeks don't know to much about them yet.
but with a four diode setup like this. # , you should get a 3.5x3.5 beam or better