Cheap but stable visible lasers diodes

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luyan luyan
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Cheap but stable visible lasers diodes

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Hi listers,

I am looking for visible laser diodes (6 colors spanning from 400-800nm) for some multiplexed wide-field imaging applications.

As I understand, for wide-field fluorescence imaging, the beam quality in terms of Gaussianess or being TEMoo mode is not of importance (right?) which makes laser choices earlier. But I am still surprised a bit how much they would cost in total. So would you have any suggestion on getting cheap but stable visible lasers that are suitable for imaging applications?

Another question I would like to get help from you, is that, for structured illumination microscopy, would a 300um core multimode fiber work as the illumination source? The original sim paper used 100 um core. I don't have much experience in this so would the core size of the multimode fiber matter in terms of affecting imaging performance?

Any input from the list are welcome and appreciated. Thank you very much in advance.

Thanks,
Lu


Rusty Nicovich Rusty Nicovich
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Want cheap?  Here's a good place to start:

http://www.dragonlasers.com/

Their 'Laser Systems' cover a reasonable range of wavelengths and powers
for a very low price.  Stability is spec'd at 10% and the beam quality will
definitely vary.  If you want even cheaper for red/green you can look at
their 'Laser Modules' which include a 150 mW 640 nm laser for $265.  No
personal experience with these units but have colleagues who have used them
for less critical imaging applications.

If you want higher specs in terms of stability (~0.5%) and beam quality
(actually TEM_{00}), then Vortran is a good source:

http://www.vortranlaser.com/

I have used these extensively and have been happy with their performance
and service.  I find them to be cheaper and easier to integrate than
offerings from other makers. Combining and fiber-coupling these diode units
(or any with a similar beam height) led to the laser launch design I
published here:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0173879

with all necessary files and build instructions here:

https://github.com/PRNicovich/NicoLase

Others may have more expertise in the SIM fiber issue, but I believe the
core diameter should not make a huge difference.  If anything the larger
core should do a better job at mode mixing and producing a more even
illumination profile at the output, which would be good.  Of course there's
the difference in magnification that needs to be taken into account, but
that should be easy to work out.

Thanks,
Rusty





On Tue, Jun 6, 2017 at 7:45 PM, Yan, Lu <[hidden email]> wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi listers,
>
> I am looking for visible laser diodes (6 colors spanning from 400-800nm)
> for some multiplexed wide-field imaging applications.
>
> As I understand, for wide-field fluorescence imaging, the beam quality in
> terms of Gaussianess or being TEMoo mode is not of importance (right?)
> which makes laser choices earlier. But I am still surprised a bit how much
> they would cost in total. So would you have any suggestion on getting cheap
> but stable visible lasers that are suitable for imaging applications?
>
> Another question I would like to get help from you, is that, for
> structured illumination microscopy, would a 300um core multimode fiber work
> as the illumination source? The original sim paper used 100 um core. I
> don't have much experience in this so would the core size of the multimode
> fiber matter in terms of affecting imaging performance?
>
> Any input from the list are welcome and appreciated. Thank you very much
> in advance.
>
> Thanks,
> Lu
>
>
>
luyan luyan
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Re: Cheap but stable visible lasers diodes

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*****

Hi Rusty,

Thanks so much for your detailed response. I will call them to find out more.

Thanks,
Lu





On Wed, Jun 7, 2017 at 9:14 AM -0700, "Rusty Nicovich" <[hidden email]<mailto:[hidden email]>> wrote:


*****
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Post images on http://www.imgur.com and include the link in your posting.
*****

Want cheap?  Here's a good place to start:

http://www.dragonlasers.com/

Their 'Laser Systems' cover a reasonable range of wavelengths and powers
for a very low price.  Stability is spec'd at 10% and the beam quality will
definitely vary.  If you want even cheaper for red/green you can look at
their 'Laser Modules' which include a 150 mW 640 nm laser for $265.  No
personal experience with these units but have colleagues who have used them
for less critical imaging applications.

If you want higher specs in terms of stability (~0.5%) and beam quality
(actually TEM_{00}), then Vortran is a good source:

http://www.vortranlaser.com/

I have used these extensively and have been happy with their performance
and service.  I find them to be cheaper and easier to integrate than
offerings from other makers. Combining and fiber-coupling these diode units
(or any with a similar beam height) led to the laser launch design I
published here:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0173879

with all necessary files and build instructions here:

https://github.com/PRNicovich/NicoLase

Others may have more expertise in the SIM fiber issue, but I believe the
core diameter should not make a huge difference.  If anything the larger
core should do a better job at mode mixing and producing a more even
illumination profile at the output, which would be good.  Of course there's
the difference in magnification that needs to be taken into account, but
that should be easy to work out.

Thanks,
Rusty





On Tue, Jun 6, 2017 at 7:45 PM, Yan, Lu  wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi listers,
>
> I am looking for visible laser diodes (6 colors spanning from 400-800nm)
> for some multiplexed wide-field imaging applications.
>
> As I understand, for wide-field fluorescence imaging, the beam quality in
> terms of Gaussianess or being TEMoo mode is not of importance (right?)
> which makes laser choices earlier. But I am still surprised a bit how much
> they would cost in total. So would you have any suggestion on getting cheap
> but stable visible lasers that are suitable for imaging applications?
>
> Another question I would like to get help from you, is that, for
> structured illumination microscopy, would a 300um core multimode fiber work
> as the illumination source? The original sim paper used 100 um core. I
> don't have much experience in this so would the core size of the multimode
> fiber matter in terms of affecting imaging performance?
>
> Any input from the list are welcome and appreciated. Thank you very much
> in advance.
>
> Thanks,
> Lu
>
>
>

zdedenn zdedenn
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Re: Cheap but stable visible lasers diodes

In reply to this post by luyan
*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi Lu,



Dragonlaser products (as pointed out by Rusty) are good, and the DPPS units
we tested were actually TEM00. There are cheaper solutions, I've done STORM
with $15 green laser pointer (these are TEM00, too, 150 mW if you're lucky,
I haven't tried SM fiber coupling), but what's the point, when even the
cleanup and combining filters will cost you $hundreds...
The main issue I had with widefield laser illumination is speckle. It's very
hard to get rid of, you'll need some rotating diffusers or beam shakers... I
would re-consider LEDs (some small, 1mm^2 power LEDs, e.g. PhlatLight) with
thicker (1 mm dia) light guide...

I found that critical illumination (the fiber end imaged into the sample)
works great, and gives you evenly distributed excitation intensity (if you
combat the laser speckle, and your fiber end is nice and clean).


The SIM thing:


If you mean three- or two-beam interference superresolution SIM, then what's
important is to focus the +/-1st orders close to the NA limit in the back
focal plane (BFP). If you use thicker fibers, the spots in the BFP will be
bigger and the contrast of the high-frequency pattern reduced. In the
extreme case where each of the order fills the whole BFP, the contrast at
the highest frequencies is zero (you are incoherently imaging some grid into
your sample, e.g. using LEDs, so the contrast is give by incoherent OTF, and
you have to lower the frequency a lot to get some contrast). The size of the
BFP spots is given by the magnification between the fiber and the objective,
which in turn determines the illuminated field of view. It also depends on
the NA of the light exiting the fiber (may be much less than the fiber NA,
depending on laser coupling) and whether you use Koehler or critical
illumination...

You can always lower the NA or FoV with irises, but that will reduce you
overall coupling efficiency, so it's better to start with a good design.

Good luck!

Best, zdenek




--
Zdenek Svindrych, Ph.D.
W.M. Keck Center for Cellular Imaging (PLSB 003)
Department of Biology,University of Virginia
409 McCormick Rd, Charlottesville, VA-22904
http://www.kcci.virginia.edu/
tel: 434-982-4869
[hidden email]

---------- Původní e-mail ----------
Od: Yan, Lu <[hidden email]>
Komu: [hidden email]
Datum: 6. 6. 2017 22:47:28
Předmět: Cheap but stable visible lasers diodes
"*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi listers,

I am looking for visible laser diodes (6 colors spanning from 400-800nm) for
some multiplexed wide-field imaging applications.

As I understand, for wide-field fluorescence imaging, the beam quality in
terms of Gaussianess or being TEMoo mode is not of importance (right?) which
makes laser choices earlier. But I am still surprised a bit how much they
would cost in total. So would you have any suggestion on getting cheap but
stable visible lasers that are suitable for imaging applications?

Another question I would like to get help from you, is that, for structured
illumination microscopy, would a 300um core multimode fiber work as the
illumination source? The original sim paper used 100 um core. I don't have
much experience in this so would the core size of the multimode fiber matter
in terms of affecting imaging performance?

Any input from the list are welcome and appreciated. Thank you very much in
advance.

Thanks,
Lu


"
luyan luyan
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Re: Cheap but stable visible lasers diodes

*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi zdenek,

Thanks much for sharing your experience with different lasers.

We are also looking to using a spinning diffuser or something called speckle reducer to deal with the speckle pattern, or a mode scrambler with a multimode fiber. Hopefully it would generate a speckle free illumination.

Regarding the SIM, do objectives usually also give the imaging side NA which I assume is what you referred to as 'NA limit in the BFP? The spec'ed NA is usually referred to the object-side NA, right?

Thanks,
Lu

-----Original Message-----
From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of [hidden email]
Sent: 2017年6月7日 10:12
To: [hidden email]
Subject: Re: Cheap but stable visible lasers diodes

*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi Lu,



Dragonlaser products (as pointed out by Rusty) are good, and the DPPS units we tested were actually TEM00. There are cheaper solutions, I've done STORM with $15 green laser pointer (these are TEM00, too, 150 mW if you're lucky, I haven't tried SM fiber coupling), but what's the point, when even the cleanup and combining filters will cost you $hundreds...
The main issue I had with widefield laser illumination is speckle. It's very hard to get rid of, you'll need some rotating diffusers or beam shakers... I would re-consider LEDs (some small, 1mm^2 power LEDs, e.g. PhlatLight) with thicker (1 mm dia) light guide...

I found that critical illumination (the fiber end imaged into the sample) works great, and gives you evenly distributed excitation intensity (if you combat the laser speckle, and your fiber end is nice and clean).


The SIM thing:


If you mean three- or two-beam interference superresolution SIM, then what's important is to focus the +/-1st orders close to the NA limit in the back focal plane (BFP). If you use thicker fibers, the spots in the BFP will be bigger and the contrast of the high-frequency pattern reduced. In the extreme case where each of the order fills the whole BFP, the contrast at the highest frequencies is zero (you are incoherently imaging some grid into your sample, e.g. using LEDs, so the contrast is give by incoherent OTF, and you have to lower the frequency a lot to get some contrast). The size of the BFP spots is given by the magnification between the fiber and the objective, which in turn determines the illuminated field of view. It also depends on the NA of the light exiting the fiber (may be much less than the fiber NA, depending on laser coupling) and whether you use Koehler or critical illumination...

You can always lower the NA or FoV with irises, but that will reduce you overall coupling efficiency, so it's better to start with a good design.

Good luck!

Best, zdenek




--
Zdenek Svindrych, Ph.D.
W.M. Keck Center for Cellular Imaging (PLSB 003) Department of Biology,University of Virginia
409 McCormick Rd, Charlottesville, VA-22904 http://www.kcci.virginia.edu/
tel: 434-982-4869
[hidden email]

---------- Původní e-mail ----------
Od: Yan, Lu <[hidden email]>
Komu: [hidden email]
Datum: 6. 6. 2017 22:47:28
Předmět: Cheap but stable visible lasers diodes
"*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi listers,

I am looking for visible laser diodes (6 colors spanning from 400-800nm) for some multiplexed wide-field imaging applications.

As I understand, for wide-field fluorescence imaging, the beam quality in terms of Gaussianess or being TEMoo mode is not of importance (right?) which makes laser choices earlier. But I am still surprised a bit how much they would cost in total. So would you have any suggestion on getting cheap but stable visible lasers that are suitable for imaging applications?

Another question I would like to get help from you, is that, for structured illumination microscopy, would a 300um core multimode fiber work as the illumination source? The original sim paper used 100 um core. I don't have much experience in this so would the core size of the multimode fiber matter in terms of affecting imaging performance?

Any input from the list are welcome and appreciated. Thank you very much in advance.

Thanks,
Lu


"
Eric Girard Eric Girard
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Re: Cheap but stable visible lasers diodes

*****
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*****

Hi Lu,

We make all fiber mode scramblers using any type of fiber, MM 50-400 um
core in silica, ZrF4, InF3, etc.

Our patented technology provides predominantly achromatic spatial
scrambling, low loss and provides >1/5 noise reduction at 10 ms integration
time.

Best regards,

Eric Girard
Sales and Engineering manager
Directeur Ventes et Ingénierie

GiGa Concept Inc
11811 Suzor-Côté
Montréal, Québec
Canada, H3M 2H8

Tél:514-745-8877
Cel:514-826-1181
Fax:514-626-6784
[hidden email]
www.gigaconcept.com


Le 8 juin 2017 12:53 AM, "Yan, Lu" <[hidden email]> a écrit :

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi zdenek,
>
> Thanks much for sharing your experience with different lasers.
>
> We are also looking to using a spinning diffuser or something called
> speckle reducer to deal with the speckle pattern, or a mode scrambler with
> a multimode fiber. Hopefully it would generate a speckle free illumination.
>
> Regarding the SIM, do objectives usually also give the imaging side NA
> which I assume is what you referred to as 'NA limit in the BFP? The spec'ed
> NA is usually referred to the object-side NA, right?
>
> Thanks,
> Lu
>
> -----Original Message-----
> From: Confocal Microscopy List [mailto:[hidden email]]
> On Behalf Of [hidden email]
> Sent: 2017年6月7日 10:12
> To: [hidden email]
> Subject: Re: Cheap but stable visible lasers diodes
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi Lu,
>
>
>
> Dragonlaser products (as pointed out by Rusty) are good, and the DPPS
> units we tested were actually TEM00. There are cheaper solutions, I've done
> STORM with $15 green laser pointer (these are TEM00, too, 150 mW if you're
> lucky, I haven't tried SM fiber coupling), but what's the point, when even
> the cleanup and combining filters will cost you $hundreds...
> The main issue I had with widefield laser illumination is speckle. It's
> very hard to get rid of, you'll need some rotating diffusers or beam
> shakers... I would re-consider LEDs (some small, 1mm^2 power LEDs, e.g.
> PhlatLight) with thicker (1 mm dia) light guide...
>
> I found that critical illumination (the fiber end imaged into the sample)
> works great, and gives you evenly distributed excitation intensity (if you
> combat the laser speckle, and your fiber end is nice and clean).
>
>
> The SIM thing:
>
>
> If you mean three- or two-beam interference superresolution SIM, then
> what's important is to focus the +/-1st orders close to the NA limit in the
> back focal plane (BFP). If you use thicker fibers, the spots in the BFP
> will be bigger and the contrast of the high-frequency pattern reduced. In
> the extreme case where each of the order fills the whole BFP, the contrast
> at the highest frequencies is zero (you are incoherently imaging some grid
> into your sample, e.g. using LEDs, so the contrast is give by incoherent
> OTF, and you have to lower the frequency a lot to get some contrast). The
> size of the BFP spots is given by the magnification between the fiber and
> the objective, which in turn determines the illuminated field of view. It
> also depends on the NA of the light exiting the fiber (may be much less
> than the fiber NA, depending on laser coupling) and whether you use Koehler
> or critical illumination...
>
> You can always lower the NA or FoV with irises, but that will reduce you
> overall coupling efficiency, so it's better to start with a good design.
>
> Good luck!
>
> Best, zdenek
>
>
>
>
> --
> Zdenek Svindrych, Ph.D.
> W.M. Keck Center for Cellular Imaging (PLSB 003) Department of
> Biology,University of Virginia
> 409 McCormick Rd, Charlottesville, VA-22904 http://www.kcci.virginia.edu/
> tel: 434-982-4869
> [hidden email]
>
> ---------- Původní e-mail ----------
> Od: Yan, Lu <[hidden email]>
> Komu: [hidden email]
> Datum: 6. 6. 2017 22:47:28
> Předmět: Cheap but stable visible lasers diodes
> "*****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi listers,
>
> I am looking for visible laser diodes (6 colors spanning from 400-800nm)
> for some multiplexed wide-field imaging applications.
>
> As I understand, for wide-field fluorescence imaging, the beam quality in
> terms of Gaussianess or being TEMoo mode is not of importance (right?)
> which makes laser choices earlier. But I am still surprised a bit how much
> they would cost in total. So would you have any suggestion on getting cheap
> but stable visible lasers that are suitable for imaging applications?
>
> Another question I would like to get help from you, is that, for
> structured illumination microscopy, would a 300um core multimode fiber work
> as the illumination source? The original sim paper used 100 um core. I
> don't have much experience in this so would the core size of the multimode
> fiber matter in terms of affecting imaging performance?
>
> Any input from the list are welcome and appreciated. Thank you very much
> in advance.
>
> Thanks,
> Lu
>
>
> "
>
zdedenn zdedenn
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Re: Cheap but stable visible lasers diodes

In reply to this post by luyan
*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi Lu,



the scramblers used by Andor - Borealis spinning discs or Vutara (now
Bruker) STORM microscopes are great. But I don't know where to get them
separately. I guess they came from Spectral Applied Research, which is now
part of Andor, which is now apparently doing nothing according to the
"Andor" link at spectral.ca :-). ... but more seriously, Andor is now part
of Oxford Instruments...

The answer to the second question: no, there is only one NA for the
(infinity corrected) objective lens. The NA in the image space is the NA of
the tube lens and that is magnification-times less than the objective NA
(which is pretty low, usually below 0.05). There is a useful concept of
"etendue", that is (simply put) the product of NA and image size, which is
conserved through the imaging system.


But what I was referring to can be also thought of as "how big part of the
objective NA you use for illumination". For widefield you probably want to
use the whole NA, so your illumination cone spreads quickly away from the
focus, which should give you less out-of-focus blur in your images.
Alternatively, you can use near-TIRF (also called "HiLo" or highly oblique
illumination), that is used in some STORM/PALM papers to get some modest
optical sectioning (again, to avoid out-of-focus light).

In superresolution SIM you want to achieve two or three distinct spots in
your objective BFP. Their sizes and separation will depend on the lenses,
fiber and grating (or LCoS or DMD or other method) you use. If the spots are
too big, the pattern contrast will decrease and you won't be able to use the
highest spatial frequencies... Also, don't forget to check the size of the
illuminated FoV, to make sure you end up with usable design. I always
recommend incorporating field and aperture stops (irises) into the
illumination path, if possible.

It's always a good idea to copy an already published design first, but I
don't know of a paper where the authors describe critical-illumination SIM
with multimode fiber. I preferred 50 um or 62.5 um / 0.22 NA fibers, because
they are widespread and cheap. If you aim at 300 um / 0.39 NA fiber, then
(the math is actually very simple) with 300 um illuminated FoV you end up
using 0.39 NA out of your available objective NA (1.33 for non-TIRF in water
environment), to me that seems a lot for SIM. You'll get better efficiency
with smaller fiber (but, as I mentioned before, you may unintentionally be
using much lower NA than your fiber limit, depending on your laser
coupling).

Sorry for the lengthy post that may not be so important for most listers. I
can give more details off-list.

Best, zdenek


---------- Původní e-mail ----------
Od: Yan, Lu <[hidden email]>
Komu: [hidden email]
Datum: 8. 6. 2017 0:55:13
Předmět: Re: Cheap but stable visible lasers diodes
"*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi zdenek,

Thanks much for sharing your experience with different lasers.

We are also looking to using a spinning diffuser or something called speckle
reducer to deal with the speckle pattern, or a mode scrambler with a
multimode fiber. Hopefully it would generate a speckle free illumination.

Regarding the SIM, do objectives usually also give the imaging side NA which
I assume is what you referred to as 'NA limit in the BFP? The spec'ed NA is
usually referred to the object-side NA, right?

Thanks,
Lu

-----Original Message-----
From: Confocal Microscopy List [mailto:[hidden email]] On
Behalf Of [hidden email]
Sent: 2017年6月7日 10:12
To: [hidden email]
Subject: Re: Cheap but stable visible lasers diodes

*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi Lu,



Dragonlaser products (as pointed out by Rusty) are good, and the DPPS units
we tested were actually TEM00. There are cheaper solutions, I've done STORM
with $15 green laser pointer (these are TEM00, too, 150 mW if you're lucky,
I haven't tried SM fiber coupling), but what's the point, when even the
cleanup and combining filters will cost you $hundreds...
The main issue I had with widefield laser illumination is speckle. It's very
hard to get rid of, you'll need some rotating diffusers or beam shakers... I
would re-consider LEDs (some small, 1mm^2 power LEDs, e.g. PhlatLight) with
thicker (1 mm dia) light guide...

I found that critical illumination (the fiber end imaged into the sample)
works great, and gives you evenly distributed excitation intensity (if you
combat the laser speckle, and your fiber end is nice and clean).


The SIM thing:


If you mean three- or two-beam interference superresolution SIM, then what's
important is to focus the +/-1st orders close to the NA limit in the back
focal plane (BFP). If you use thicker fibers, the spots in the BFP will be
bigger and the contrast of the high-frequency pattern reduced. In the
extreme case where each of the order fills the whole BFP, the contrast at
the highest frequencies is zero (you are incoherently imaging some grid into
your sample, e.g. using LEDs, so the contrast is give by incoherent OTF, and
you have to lower the frequency a lot to get some contrast). The size of the
BFP spots is given by the magnification between the fiber and the objective,
which in turn determines the illuminated field of view. It also depends on
the NA of the light exiting the fiber (may be much less than the fiber NA,
depending on laser coupling) and whether you use Koehler or critical
illumination...

You can always lower the NA or FoV with irises, but that will reduce you
overall coupling efficiency, so it's better to start with a good design.

Good luck!

Best, zdenek




--
Zdenek Svindrych, Ph.D.
W.M. Keck Center for Cellular Imaging (PLSB 003) Department of Biology,
University of Virginia
409 McCormick Rd, Charlottesville, VA-22904 http://www.kcci.virginia.edu/ 
tel: 434-982-4869
[hidden email]

---------- Původní e-mail ----------
Od: Yan, Lu <[hidden email]>
Komu: [hidden email]
Datum: 6. 6. 2017 22:47:28
Předmět: Cheap but stable visible lasers diodes
"*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi listers,

I am looking for visible laser diodes (6 colors spanning from 400-800nm) for
some multiplexed wide-field imaging applications.

As I understand, for wide-field fluorescence imaging, the beam quality in
terms of Gaussianess or being TEMoo mode is not of importance (right?) which
makes laser choices earlier. But I am still surprised a bit how much they
would cost in total. So would you have any suggestion on getting cheap but
stable visible lasers that are suitable for imaging applications?

Another question I would like to get help from you, is that, for structured
illumination microscopy, would a 300um core multimode fiber work as the
illumination source? The original sim paper used 100 um core. I don't have
much experience in this so would the core size of the multimode fiber matter
in terms of affecting imaging performance?

Any input from the list are welcome and appreciated. Thank you very much in
advance.

Thanks,
Lu


"
"
john.oreopoulos john.oreopoulos
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Re: Cheap but stable visible lasers diodes

*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Hi,

Spectral Applied Research is Andor now (which is itself a division of  
Oxford Instruments). The old Spectral website still exists, but any  
inquiries relating to the patented Borealis illumination technology  
should be directed to your local Andor representative. We are now part  
of the Andor R&D team and are actively involved in the continuing  
development of existing and new microscopy products. Definitely not  
idle over here!

John Oreopoulos
Staff Scientist
Andor Technology
Website:  www.andor.com



Quoting [hidden email]:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi Lu,
>
>
>
> the scramblers used by Andor - Borealis spinning discs or Vutara (now
> Bruker) STORM microscopes are great. But I don't know where to get them
> separately. I guess they came from Spectral Applied Research, which is now
> part of Andor, which is now apparently doing nothing according to the
> "Andor" link at spectral.ca :-). ... but more seriously, Andor is now part
> of Oxford Instruments...
>
> The answer to the second question: no, there is only one NA for the
> (infinity corrected) objective lens. The NA in the image space is the NA of
> the tube lens and that is magnification-times less than the objective NA
> (which is pretty low, usually below 0.05). There is a useful concept of
> "etendue", that is (simply put) the product of NA and image size, which is
> conserved through the imaging system.
>
>
> But what I was referring to can be also thought of as "how big part of the
> objective NA you use for illumination". For widefield you probably want to
> use the whole NA, so your illumination cone spreads quickly away from the
> focus, which should give you less out-of-focus blur in your images.
> Alternatively, you can use near-TIRF (also called "HiLo" or highly oblique
> illumination), that is used in some STORM/PALM papers to get some modest
> optical sectioning (again, to avoid out-of-focus light).
>
> In superresolution SIM you want to achieve two or three distinct spots in
> your objective BFP. Their sizes and separation will depend on the lenses,
> fiber and grating (or LCoS or DMD or other method) you use. If the spots are
> too big, the pattern contrast will decrease and you won't be able to use the
> highest spatial frequencies... Also, don't forget to check the size of the
> illuminated FoV, to make sure you end up with usable design. I always
> recommend incorporating field and aperture stops (irises) into the
> illumination path, if possible.
>
> It's always a good idea to copy an already published design first, but I
> don't know of a paper where the authors describe critical-illumination SIM
> with multimode fiber. I preferred 50 um or 62.5 um / 0.22 NA fibers, because
> they are widespread and cheap. If you aim at 300 um / 0.39 NA fiber, then
> (the math is actually very simple) with 300 um illuminated FoV you end up
> using 0.39 NA out of your available objective NA (1.33 for non-TIRF in water
> environment), to me that seems a lot for SIM. You'll get better efficiency
> with smaller fiber (but, as I mentioned before, you may unintentionally be
> using much lower NA than your fiber limit, depending on your laser
> coupling).
>
> Sorry for the lengthy post that may not be so important for most listers. I
> can give more details off-list.
>
> Best, zdenek
>
>
> ---------- P?vodní e-mail ----------
> Od: Yan, Lu <[hidden email]>
> Komu: [hidden email]
> Datum: 8. 6. 2017 0:55:13
> P?edm?t: Re: Cheap but stable visible lasers diodes
> "*****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi zdenek,
>
> Thanks much for sharing your experience with different lasers.
>
> We are also looking to using a spinning diffuser or something called speckle
> reducer to deal with the speckle pattern, or a mode scrambler with a
> multimode fiber. Hopefully it would generate a speckle free illumination.
>
> Regarding the SIM, do objectives usually also give the imaging side NA which
> I assume is what you referred to as 'NA limit in the BFP? The spec'ed NA is
> usually referred to the object-side NA, right?
>
> Thanks,
> Lu
>
> -----Original Message-----
> From: Confocal Microscopy List [mailto:[hidden email]] On
> Behalf Of [hidden email]
> Sent: 2017?6?7? 10:12
> To: [hidden email]
> Subject: Re: Cheap but stable visible lasers diodes
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi Lu,
>
>
>
> Dragonlaser products (as pointed out by Rusty) are good, and the DPPS units
> we tested were actually TEM00. There are cheaper solutions, I've done STORM
> with $15 green laser pointer (these are TEM00, too, 150 mW if you're lucky,
> I haven't tried SM fiber coupling), but what's the point, when even the
> cleanup and combining filters will cost you $hundreds...
> The main issue I had with widefield laser illumination is speckle. It's very
> hard to get rid of, you'll need some rotating diffusers or beam shakers... I
> would re-consider LEDs (some small, 1mm^2 power LEDs, e.g. PhlatLight) with
> thicker (1 mm dia) light guide...
>
> I found that critical illumination (the fiber end imaged into the sample)
> works great, and gives you evenly distributed excitation intensity (if you
> combat the laser speckle, and your fiber end is nice and clean).
>
>
> The SIM thing:
>
>
> If you mean three- or two-beam interference superresolution SIM, then what's
> important is to focus the +/-1st orders close to the NA limit in the back
> focal plane (BFP). If you use thicker fibers, the spots in the BFP will be
> bigger and the contrast of the high-frequency pattern reduced. In the
> extreme case where each of the order fills the whole BFP, the contrast at
> the highest frequencies is zero (you are incoherently imaging some grid into
> your sample, e.g. using LEDs, so the contrast is give by incoherent OTF, and
> you have to lower the frequency a lot to get some contrast). The size of the
> BFP spots is given by the magnification between the fiber and the objective,
> which in turn determines the illuminated field of view. It also depends on
> the NA of the light exiting the fiber (may be much less than the fiber NA,
> depending on laser coupling) and whether you use Koehler or critical
> illumination...
>
> You can always lower the NA or FoV with irises, but that will reduce you
> overall coupling efficiency, so it's better to start with a good design.
>
> Good luck!
>
> Best, zdenek
>
>
>
>
> --
> Zdenek Svindrych, Ph.D.
> W.M. Keck Center for Cellular Imaging (PLSB 003) Department of Biology,
> University of Virginia
> 409 McCormick Rd, Charlottesville, VA-22904 http://www.kcci.virginia.edu/
> tel: 434-982-4869
> [hidden email]
>
> ---------- P?vodní e-mail ----------
> Od: Yan, Lu <[hidden email]>
> Komu: [hidden email]
> Datum: 6. 6. 2017 22:47:28
> P?edm?t: Cheap but stable visible lasers diodes
> "*****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi listers,
>
> I am looking for visible laser diodes (6 colors spanning from 400-800nm) for
> some multiplexed wide-field imaging applications.
>
> As I understand, for wide-field fluorescence imaging, the beam quality in
> terms of Gaussianess or being TEMoo mode is not of importance (right?) which
> makes laser choices earlier. But I am still surprised a bit how much they
> would cost in total. So would you have any suggestion on getting cheap but
> stable visible lasers that are suitable for imaging applications?
>
> Another question I would like to get help from you, is that, for structured
> illumination microscopy, would a 300um core multimode fiber work as the
> illumination source? The original sim paper used 100 um core. I don't have
> much experience in this so would the core size of the multimode fiber matter
> in terms of affecting imaging performance?
>
> Any input from the list are welcome and appreciated. Thank you very much in
> advance.
>
> Thanks,
> Lu
>
>
> "
> "
>
zdedenn zdedenn
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Open this post in threaded view
|  
Report Content as Inappropriate

Re: Cheap but stable visible lasers diodes

*****
To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
Post images on http://www.imgur.com and include the link in your posting.
*****

Sorry John,
this is just a misunderstanding. What I was pointing on is that when you
clicked the "Andor" link on the top of the spectral.ca page, it directed you
to andorplc.com instead of andor.com, good that it's fixed now (i.e. deleted
completely and redirected to Andor). Just thought it was funny... :-).

You're doing a great job, for sure! (no commercial interest)

zdenek


---------- Původní e-mail ----------
Od: [hidden email]
Komu: Confocal Microscopy List <[hidden email]>, zdedenn@
GMAIL.COM
Datum: 8. 6. 2017 11:42:59
Předmět: Re: Cheap but stable visible lasers diodes
"Hi,

Spectral Applied Research is Andor now (which is itself a division of
Oxford Instruments). The old Spectral website still exists, but any
inquiries relating to the patented Borealis illumination technology
should be directed to your local Andor representative. We are now part
of the Andor R&D team and are actively involved in the continuing
development of existing and new microscopy products. Definitely not
idle over here!

John Oreopoulos
Staff Scientist
Andor Technology
Website: www.andor.com



Quoting [hidden email]:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi Lu,
>
>
>
> the scramblers used by Andor - Borealis spinning discs or Vutara (now
> Bruker) STORM microscopes are great. But I don't know where to get them
> separately. I guess they came from Spectral Applied Research, which is now

> part of Andor, which is now apparently doing nothing according to the
> "Andor" link at spectral.ca :-). ... but more seriously, Andor is now part

> of Oxford Instruments...
>
> The answer to the second question: no, there is only one NA for the
> (infinity corrected) objective lens. The NA in the image space is the NA
of
> the tube lens and that is magnification-times less than the objective NA
> (which is pretty low, usually below 0.05). There is a useful concept of
> "etendue", that is (simply put) the product of NA and image size, which is

> conserved through the imaging system.
>
>
> But what I was referring to can be also thought of as "how big part of the

> objective NA you use for illumination". For widefield you probably want to

> use the whole NA, so your illumination cone spreads quickly away from the
> focus, which should give you less out-of-focus blur in your images.
> Alternatively, you can use near-TIRF (also called "HiLo" or highly oblique

> illumination), that is used in some STORM/PALM papers to get some modest
> optical sectioning (again, to avoid out-of-focus light).
>
> In superresolution SIM you want to achieve two or three distinct spots in
> your objective BFP. Their sizes and separation will depend on the lenses,
> fiber and grating (or LCoS or DMD or other method) you use. If the spots
are
> too big, the pattern contrast will decrease and you won't be able to use
the
> highest spatial frequencies... Also, don't forget to check the size of the

> illuminated FoV, to make sure you end up with usable design. I always
> recommend incorporating field and aperture stops (irises) into the
> illumination path, if possible.
>
> It's always a good idea to copy an already published design first, but I
> don't know of a paper where the authors describe critical-illumination SIM

> with multimode fiber. I preferred 50 um or 62.5 um / 0.22 NA fibers,
because
> they are widespread and cheap. If you aim at 300 um / 0.39 NA fiber, then
> (the math is actually very simple) with 300 um illuminated FoV you end up
> using 0.39 NA out of your available objective NA (1.33 for non-TIRF in
water
> environment), to me that seems a lot for SIM. You'll get better efficiency

> with smaller fiber (but, as I mentioned before, you may unintentionally be

> using much lower NA than your fiber limit, depending on your laser
> coupling).
>
> Sorry for the lengthy post that may not be so important for most listers.
I

> can give more details off-list.
>
> Best, zdenek
>
>
> ---------- P?vodní e-mail ----------
> Od: Yan, Lu <[hidden email]>
> Komu: [hidden email]
> Datum: 8. 6. 2017 0:55:13
> P?edm?t: Re: Cheap but stable visible lasers diodes
> "*****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi zdenek,
>
> Thanks much for sharing your experience with different lasers.
>
> We are also looking to using a spinning diffuser or something called
speckle
> reducer to deal with the speckle pattern, or a mode scrambler with a
> multimode fiber. Hopefully it would generate a speckle free illumination.
>
> Regarding the SIM, do objectives usually also give the imaging side NA
which
> I assume is what you referred to as 'NA limit in the BFP? The spec'ed NA
is
> usually referred to the object-side NA, right?
>
> Thanks,
> Lu
>
> -----Original Message-----
> From: Confocal Microscopy List [mailto:[hidden email]]
On

> Behalf Of [hidden email]
> Sent: 2017?6?7? 10:12
> To: [hidden email]
> Subject: Re: Cheap but stable visible lasers diodes
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi Lu,
>
>
>
> Dragonlaser products (as pointed out by Rusty) are good, and the DPPS
units
> we tested were actually TEM00. There are cheaper solutions, I've done
STORM
> with $15 green laser pointer (these are TEM00, too, 150 mW if you're
lucky,
> I haven't tried SM fiber coupling), but what's the point, when even the
> cleanup and combining filters will cost you $hundreds...
> The main issue I had with widefield laser illumination is speckle. It's
very
> hard to get rid of, you'll need some rotating diffusers or beam shakers...
I
> would re-consider LEDs (some small, 1mm^2 power LEDs, e.g. PhlatLight)
with
> thicker (1 mm dia) light guide...
>
> I found that critical illumination (the fiber end imaged into the sample)
> works great, and gives you evenly distributed excitation intensity (if you

> combat the laser speckle, and your fiber end is nice and clean).
>
>
> The SIM thing:
>
>
> If you mean three- or two-beam interference superresolution SIM, then
what's
> important is to focus the +/-1st orders close to the NA limit in the back
> focal plane (BFP). If you use thicker fibers, the spots in the BFP will be

> bigger and the contrast of the high-frequency pattern reduced. In the
> extreme case where each of the order fills the whole BFP, the contrast at
> the highest frequencies is zero (you are incoherently imaging some grid
into
> your sample, e.g. using LEDs, so the contrast is give by incoherent OTF,
and
> you have to lower the frequency a lot to get some contrast). The size of
the
> BFP spots is given by the magnification between the fiber and the
objective,
> which in turn determines the illuminated field of view. It also depends on

> the NA of the light exiting the fiber (may be much less than the fiber NA,

> depending on laser coupling) and whether you use Koehler or critical
> illumination...
>
> You can always lower the NA or FoV with irises, but that will reduce you
> overall coupling efficiency, so it's better to start with a good design.
>
> Good luck!
>
> Best, zdenek
>
>
>
>
> --
> Zdenek Svindrych, Ph.D.
> W.M. Keck Center for Cellular Imaging (PLSB 003) Department of Biology,
> University of Virginia
> 409 McCormick Rd, Charlottesville, VA-22904 http://www.kcci.virginia.edu/
> tel: 434-982-4869
> [hidden email]
>
> ---------- P?vodní e-mail ----------
> Od: Yan, Lu <[hidden email]>
> Komu: [hidden email]
> Datum: 6. 6. 2017 22:47:28
> P?edm?t: Cheap but stable visible lasers diodes
> "*****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> Post images on http://www.imgur.com and include the link in your posting.
> *****
>
> Hi listers,
>
> I am looking for visible laser diodes (6 colors spanning from 400-800nm)
for
> some multiplexed wide-field imaging applications.
>
> As I understand, for wide-field fluorescence imaging, the beam quality in
> terms of Gaussianess or being TEMoo mode is not of importance (right?)
which
> makes laser choices earlier. But I am still surprised a bit how much they
> would cost in total. So would you have any suggestion on getting cheap but

> stable visible lasers that are suitable for imaging applications?
>
> Another question I would like to get help from you, is that, for
structured
> illumination microscopy, would a 300um core multimode fiber work as the
> illumination source? The original sim paper used 100 um core. I don't have

> much experience in this so would the core size of the multimode fiber
matter
> in terms of affecting imaging performance?
>
> Any input from the list are welcome and appreciated. Thank you very much
in
> advance.
>
> Thanks,
> Lu
>
>
> "
> "
>



"
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