Dichroic mirror and high NA objective effects on 1064nm laser polarization

[Matthew Nicholas-2]

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Dear list,
I'm curious about the effects of reflection off a dichroic mirror and
transmission through a high-NA microscope objective on the polarization
state of of laser light. In particular, I want to know how a 1064nm beam
used for optical trapping might be affected, so this is not actually a
confocal question, but I figured that these effects are likely of more
general interest, and that any wavelength-specific issues might also
affect multiphoton setups.

My question is essentially: how do dichroic mirrors and high-NA
objectives (mine is a 1.49 Nikon TIRF objective) change the polarization
of a linearly polarized beam, if at all? Can they induce ellipticity?
I've seen some (usually vague) references to both elements affecting
polarization, but I haven't been able to dig up any papers giving clear
explanations about (a) the underlying mechanism or (b) the magnitude of
the effects.

Regarding the dichroic, it is clear to me that the S and P components
will have different Fresnel reflection coefficients given the dielectric
coating. I can see how this would change the ellipticity of an
elliptically or circularly polarized beam, or slightly rotate the
polarization of a linearly polarized beam (if it were not pure S or P
polarization). To induce ellipticity in a linear beam, there would have
to be some phase retardance induced, which I believe is also possible,
but the mechanism is not clear. Is this dependent somehow on the angle
of incidence as well?

The effect of the objective is even less clear to me, as is the apparent
distinction between effects of high-NA vs. low-NA objectives. Naively, I
would guess it would arise from birefringence (perhaps induced by stress
on the internal optical elements?).

If anyone can provide any insights, or point me in the direction of
informative papers I may have missed, I'd be grateful.

Thanks in advance,
Matt

[Gregg Jarvis]

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Matt,
Have you read this article?


http://www.semrock.com/understanding-polarization.aspx

On Fri, Jan 11, 2013 at 10:42 AM, Matthew Nicholas <
[hidden email]> wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/**wa?A0=confocalmicroscopy<http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>
> *****
>
> Dear list,
> I'm curious about the effects of reflection off a dichroic mirror and
> transmission through a high-NA microscope objective on the polarization
> state of of laser light. In particular, I want to know how a 1064nm beam
> used for optical trapping might be affected, so this is not actually a
> confocal question, but I figured that these effects are likely of more
> general interest, and that any wavelength-specific issues might also affect
> multiphoton setups.
>
> My question is essentially: how do dichroic mirrors and high-NA objectives
> (mine is a 1.49 Nikon TIRF objective) change the polarization of a linearly
> polarized beam, if at all? Can they induce ellipticity? I've seen some
> (usually vague) references to both elements affecting polarization, but I
> haven't been able to dig up any papers giving clear explanations about (a)
> the underlying mechanism or (b) the magnitude of the effects.
>
> Regarding the dichroic, it is clear to me that the S and P components will
> have different Fresnel reflection coefficients given the dielectric
> coating. I can see how this would change the ellipticity of an elliptically
> or circularly polarized beam, or slightly rotate the polarization of a
> linearly polarized beam (if it were not pure S or P polarization). To
> induce ellipticity in a linear beam, there would have to be some phase
> retardance induced, which I believe is also possible, but the mechanism is
> not clear. Is this dependent somehow on the angle of incidence as well?
>
> The effect of the objective is even less clear to me, as is the apparent
> distinction between effects of high-NA vs. low-NA objectives. Naively, I
> would guess it would arise from birefringence (perhaps induced by stress on
> the internal optical elements?).
>
> If anyone can provide any insights, or point me in the direction of
> informative papers I may have missed, I'd be grateful.
>
> Thanks in advance,
> Matt
>

--
Gregg Jarvis
Senior Spectroscopist
Advanced Products Group
Omeag Optical Inc.

Delta Campus, 21 Omega Drive
Brattleboro, VT 05301, USA
Tel: [phone]
[hidden email]

[John Oreopoulos]

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Dear Matt,

The issues with polarization stemming from the use of high NA objective lenses are well documented by some of the early work by Daniel Axelrod:

Axelrod, D., Carbocyanine dye orientation in red-cell membrane studied by microscopic fluorescence polarization. Biophysical Journal, 1979. 26(3): p. 557-573.

Axelrod, D., Fluorescence polarization microscopy, in Methods in cell biology, T. Langsing and Y. Wang, Editors. 1989, Academic Press: San Diego. p. 333-352.

Some later work by people who were at one time students of Dr. Axelrod examined the problem in more detail, but mainly dealing with the polarization of fluorescence emission light as opposed to the excitation light. Jorg Enderlein has also looked at this topic in some detail as I recall. Figure 5 in the second reference I mentioned would probably be most useful to you. I'm not up-to-date on the laser trapping literature, but I'm sure this topic is also discussed in more detail there.

As for the dichroic mirrors, my understanding is that the polarization can be fairly well maintained as long as you input a polarization that is either "s" or "p" (the intensities of the "s" or "p" polarized beams will be slightly different however). It's the angles in between "s" and "p" polarization that can depolarize the light more, and I think that is due to the phase changes that are induced at these angles, and also it has something to do with the coatings on the mirror itself. Perhaps one of the filter companies listening in on this listserver can comment on that more.


John Oreopoulos
Staff Scientist
Spectral Applied Research
Richmond Hill, Ontario
Canada
www.spectral.ca



On 2013-01-11, at 10:42 AM, Matthew Nicholas wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> Dear list,
> I'm curious about the effects of reflection off a dichroic mirror and transmission through a high-NA microscope objective on the polarization state of of laser light. In particular, I want to know how a 1064nm beam used for optical trapping might be affected, so this is not actually a confocal question, but I figured that these effects are likely of more general interest, and that any wavelength-specific issues might also affect multiphoton setups.
>
> My question is essentially: how do dichroic mirrors and high-NA objectives (mine is a 1.49 Nikon TIRF objective) change the polarization of a linearly polarized beam, if at all? Can they induce ellipticity? I've seen some (usually vague) references to both elements affecting polarization, but I haven't been able to dig up any papers giving clear explanations about (a) the underlying mechanism or (b) the magnitude of the effects.
>
> Regarding the dichroic, it is clear to me that the S and P components will have different Fresnel reflection coefficients given the dielectric coating. I can see how this would change the ellipticity of an elliptically or circularly polarized beam, or slightly rotate the polarization of a linearly polarized beam (if it were not pure S or P polarization). To induce ellipticity in a linear beam, there would have to be some phase retardance induced, which I believe is also possible, but the mechanism is not clear. Is this dependent somehow on the angle of incidence as well?
>
> The effect of the objective is even less clear to me, as is the apparent distinction between effects of high-NA vs. low-NA objectives. Naively, I would guess it would arise from birefringence (perhaps induced by stress on the internal optical elements?).
>
> If anyone can provide any insights, or point me in the direction of informative papers I may have missed, I'd be grateful.
>
> Thanks in advance,
> Matt

[Craig Brideau]

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http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
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I did a poster/paper presentation for polarization issues at Photonics West
last year.  I've forwarded a copy to Matthew.  The gist of it is that the
dielectric layers in dichroics act as waveplates, so they can really mess
up your polarization state.  From experience, I've found that if you have
strongly linearly polarized light and hit the dirchroic directly in the s
or p plane you are generally OK, but if there is any deviation from this it
can start to 'tumble' and you get ellipticity and the like.  I got around
this by building a polarization compensation system for our own 2p
microscope, which is the crux of the paper.

Craig


On Fri, Jan 11, 2013 at 9:58 AM, John Oreopoulos <
[hidden email]> wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> Dear Matt,
>
> The issues with polarization stemming from the use of high NA objective
> lenses are well documented by some of the early work by Daniel Axelrod:
>
> Axelrod, D., Carbocyanine dye orientation in red-cell membrane studied by
> microscopic fluorescence polarization. Biophysical Journal, 1979. 26(3): p.
> 557-573.
>
> Axelrod, D., Fluorescence polarization microscopy, in Methods in cell
> biology, T. Langsing and Y. Wang, Editors. 1989, Academic Press: San Diego.
> p. 333-352.
>
> Some later work by people who were at one time students of Dr. Axelrod
> examined the problem in more detail, but mainly dealing with the
> polarization of fluorescence emission light as opposed to the excitation
> light. Jorg Enderlein has also looked at this topic in some detail as I
> recall. Figure 5 in the second reference I mentioned would probably be most
> useful to you. I'm not up-to-date on the laser trapping literature, but I'm
> sure this topic is also discussed in more detail there.
>
> As for the dichroic mirrors, my understanding is that the polarization can
> be fairly well maintained as long as you input a polarization that is
> either "s" or "p" (the intensities of the "s" or "p" polarized beams will
> be slightly different however). It's the angles in between "s" and "p"
> polarization that can depolarize the light more, and I think that is due to
> the phase changes that are induced at these angles, and also it has
> something to do with the coatings on the mirror itself. Perhaps one of the
> filter companies listening in on this listserver can comment on that more.
>
>
> John Oreopoulos
> Staff Scientist
> Spectral Applied Research
> Richmond Hill, Ontario
> Canada
> www.spectral.ca
>
>
>
> On 2013-01-11, at 10:42 AM, Matthew Nicholas wrote:
>
> > *****
> > To join, leave or search the confocal microscopy listserv, go to:
> > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> > *****
> >
> > Dear list,
> > I'm curious about the effects of reflection off a dichroic mirror and
> transmission through a high-NA microscope objective on the polarization
> state of of laser light. In particular, I want to know how a 1064nm beam
> used for optical trapping might be affected, so this is not actually a
> confocal question, but I figured that these effects are likely of more
> general interest, and that any wavelength-specific issues might also affect
> multiphoton setups.
> >
> > My question is essentially: how do dichroic mirrors and high-NA
> objectives (mine is a 1.49 Nikon TIRF objective) change the polarization of
> a linearly polarized beam, if at all? Can they induce ellipticity? I've
> seen some (usually vague) references to both elements affecting
> polarization, but I haven't been able to dig up any papers giving clear
> explanations about (a) the underlying mechanism or (b) the magnitude of the
> effects.
> >
> > Regarding the dichroic, it is clear to me that the S and P components
> will have different Fresnel reflection coefficients given the dielectric
> coating. I can see how this would change the ellipticity of an elliptically
> or circularly polarized beam, or slightly rotate the polarization of a
> linearly polarized beam (if it were not pure S or P polarization). To
> induce ellipticity in a linear beam, there would have to be some phase
> retardance induced, which I believe is also possible, but the mechanism is
> not clear. Is this dependent somehow on the angle of incidence as well?
> >
> > The effect of the objective is even less clear to me, as is the apparent
> distinction between effects of high-NA vs. low-NA objectives. Naively, I
> would guess it would arise from birefringence (perhaps induced by stress on
> the internal optical elements?).
> >
> > If anyone can provide any insights, or point me in the direction of
> informative papers I may have missed, I'd be grateful.
> >
> > Thanks in advance,
> > Matt
>

[Matthew Nicholas-2]

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To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
*****

Thanks very much to Gregg, John and Craig for the resources. Craig, as
it turns out, I'd requested your paper on interlibrary loan and was
waiting to receive a copy. I was sure I recognized the first author's
name, but could not recall from where. Now I know :) Tomorrow I'll have
a look at the Axelrod chapter on fluorescence polarization, which also
looks promising.

Matt

On 1/11/13 3:32 PM, Craig Brideau wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> I did a poster/paper presentation for polarization issues at Photonics West
> last year.  I've forwarded a copy to Matthew.  The gist of it is that the
> dielectric layers in dichroics act as waveplates, so they can really mess
> up your polarization state.  From experience, I've found that if you have
> strongly linearly polarized light and hit the dirchroic directly in the s
> or p plane you are generally OK, but if there is any deviation from this it
> can start to 'tumble' and you get ellipticity and the like.  I got around
> this by building a polarization compensation system for our own 2p
> microscope, which is the crux of the paper.
>
> Craig
>
>
> On Fri, Jan 11, 2013 at 9:58 AM, John Oreopoulos<
> [hidden email]>  wrote:
>
>> *****
>> To join, leave or search the confocal microscopy listserv, go to:
>> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> *****
>>
>> Dear Matt,
>>
>> The issues with polarization stemming from the use of high NA objective
>> lenses are well documented by some of the early work by Daniel Axelrod:
>>
>> Axelrod, D., Carbocyanine dye orientation in red-cell membrane studied by
>> microscopic fluorescence polarization. Biophysical Journal, 1979. 26(3): p.
>> 557-573.
>>
>> Axelrod, D., Fluorescence polarization microscopy, in Methods in cell
>> biology, T. Langsing and Y. Wang, Editors. 1989, Academic Press: San Diego.
>> p. 333-352.
>>
>> Some later work by people who were at one time students of Dr. Axelrod
>> examined the problem in more detail, but mainly dealing with the
>> polarization of fluorescence emission light as opposed to the excitation
>> light. Jorg Enderlein has also looked at this topic in some detail as I
>> recall. Figure 5 in the second reference I mentioned would probably be most
>> useful to you. I'm not up-to-date on the laser trapping literature, but I'm
>> sure this topic is also discussed in more detail there.
>>
>> As for the dichroic mirrors, my understanding is that the polarization can
>> be fairly well maintained as long as you input a polarization that is
>> either "s" or "p" (the intensities of the "s" or "p" polarized beams will
>> be slightly different however). It's the angles in between "s" and "p"
>> polarization that can depolarize the light more, and I think that is due to
>> the phase changes that are induced at these angles, and also it has
>> something to do with the coatings on the mirror itself. Perhaps one of the
>> filter companies listening in on this listserver can comment on that more.
>>
>>
>> John Oreopoulos
>> Staff Scientist
>> Spectral Applied Research
>> Richmond Hill, Ontario
>> Canada
>> www.spectral.ca
>>
>>
>>
>> On 2013-01-11, at 10:42 AM, Matthew Nicholas wrote:
>>
>>> *****
>>> To join, leave or search the confocal microscopy listserv, go to:
>>> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>>> *****
>>>
>>> Dear list,
>>> I'm curious about the effects of reflection off a dichroic mirror and
>> transmission through a high-NA microscope objective on the polarization
>> state of of laser light. In particular, I want to know how a 1064nm beam
>> used for optical trapping might be affected, so this is not actually a
>> confocal question, but I figured that these effects are likely of more
>> general interest, and that any wavelength-specific issues might also affect
>> multiphoton setups.
>>> My question is essentially: how do dichroic mirrors and high-NA
>> objectives (mine is a 1.49 Nikon TIRF objective) change the polarization of
>> a linearly polarized beam, if at all? Can they induce ellipticity? I've
>> seen some (usually vague) references to both elements affecting
>> polarization, but I haven't been able to dig up any papers giving clear
>> explanations about (a) the underlying mechanism or (b) the magnitude of the
>> effects.
>>> Regarding the dichroic, it is clear to me that the S and P components
>> will have different Fresnel reflection coefficients given the dielectric
>> coating. I can see how this would change the ellipticity of an elliptically
>> or circularly polarized beam, or slightly rotate the polarization of a
>> linearly polarized beam (if it were not pure S or P polarization). To
>> induce ellipticity in a linear beam, there would have to be some phase
>> retardance induced, which I believe is also possible, but the mechanism is
>> not clear. Is this dependent somehow on the angle of incidence as well?
>>> The effect of the objective is even less clear to me, as is the apparent
>> distinction between effects of high-NA vs. low-NA objectives. Naively, I
>> would guess it would arise from birefringence (perhaps induced by stress on
>> the internal optical elements?).
>>> If anyone can provide any insights, or point me in the direction of
>> informative papers I may have missed, I'd be grateful.
>>> Thanks in advance,
>>> Matt

--
Matthew Nicholas
Medical Scientist Training Program Student
Laboratory of Arne Gennerich
Department of Anatomy and Structural Biology
Albert Einstein College of Medicine
Forchheimer Building, Room 628
1300 Morris Park Avenue
Bronx, New York 10461
718.430.3446
[hidden email]

[Craig Brideau]

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To join, leave or search the confocal microscopy listserv, go to:
http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
*****

I'm a card carrying member of the microscopists' peanut gallery. @:-)  I
hope the paper is helpful!  Also, if anyone happens to be going to
Photonics West BiOS this year I'm giving a talk on Optical Parametric
Amplifiers (OPAs) for microscopy on the Saturday.  I will be mentioning the
polarization control system during the talk, and of course will hang around
later for questions should anyone want to just hang out and chat.

Craig



On Sat, Jan 12, 2013 at 1:25 AM, Matthew Nicholas <
[hidden email]> wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/**wa?A0=confocalmicroscopy<http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>
> *****
>
> Thanks very much to Gregg, John and Craig for the resources. Craig, as it
> turns out, I'd requested your paper on interlibrary loan and was waiting to
> receive a copy. I was sure I recognized the first author's name, but could
> not recall from where. Now I know :) Tomorrow I'll have a look at the
> Axelrod chapter on fluorescence polarization, which also looks promising.
>
> Matt
>
>
> On 1/11/13 3:32 PM, Craig Brideau wrote:
>
>> *****
>> To join, leave or search the confocal microscopy listserv, go to:
>> http://lists.umn.edu/cgi-bin/**wa?A0=confocalmicroscopy<http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>
>> *****
>>
>> I did a poster/paper presentation for polarization issues at Photonics
>> West
>> last year.  I've forwarded a copy to Matthew.  The gist of it is that the
>> dielectric layers in dichroics act as waveplates, so they can really mess
>> up your polarization state.  From experience, I've found that if you have
>> strongly linearly polarized light and hit the dirchroic directly in the s
>> or p plane you are generally OK, but if there is any deviation from this
>> it
>> can start to 'tumble' and you get ellipticity and the like.  I got around
>> this by building a polarization compensation system for our own 2p
>> microscope, which is the crux of the paper.
>>
>> Craig
>>
>>
>> On Fri, Jan 11, 2013 at 9:58 AM, John Oreopoulos<
>> [hidden email]>  wrote:
>>
>>  *****
>>> To join, leave or search the confocal microscopy listserv, go to:
>>> http://lists.umn.edu/cgi-bin/**wa?A0=confocalmicroscopy<http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>
>>> *****
>>>
>>> Dear Matt,
>>>
>>> The issues with polarization stemming from the use of high NA objective
>>> lenses are well documented by some of the early work by Daniel Axelrod:
>>>
>>> Axelrod, D., Carbocyanine dye orientation in red-cell membrane studied by
>>> microscopic fluorescence polarization. Biophysical Journal, 1979. 26(3):
>>> p.
>>> 557-573.
>>>
>>> Axelrod, D., Fluorescence polarization microscopy, in Methods in cell
>>> biology, T. Langsing and Y. Wang, Editors. 1989, Academic Press: San
>>> Diego.
>>> p. 333-352.
>>>
>>> Some later work by people who were at one time students of Dr. Axelrod
>>> examined the problem in more detail, but mainly dealing with the
>>> polarization of fluorescence emission light as opposed to the excitation
>>> light. Jorg Enderlein has also looked at this topic in some detail as I
>>> recall. Figure 5 in the second reference I mentioned would probably be
>>> most
>>> useful to you. I'm not up-to-date on the laser trapping literature, but
>>> I'm
>>> sure this topic is also discussed in more detail there.
>>>
>>> As for the dichroic mirrors, my understanding is that the polarization
>>> can
>>> be fairly well maintained as long as you input a polarization that is
>>> either "s" or "p" (the intensities of the "s" or "p" polarized beams will
>>> be slightly different however). It's the angles in between "s" and "p"
>>> polarization that can depolarize the light more, and I think that is due
>>> to
>>> the phase changes that are induced at these angles, and also it has
>>> something to do with the coatings on the mirror itself. Perhaps one of
>>> the
>>> filter companies listening in on this listserver can comment on that
>>> more.
>>>
>>>
>>> John Oreopoulos
>>> Staff Scientist
>>> Spectral Applied Research
>>> Richmond Hill, Ontario
>>> Canada
>>> www.spectral.ca
>>>
>>>
>>>
>>> On 2013-01-11, at 10:42 AM, Matthew Nicholas wrote:
>>>
>>>  *****
>>>> To join, leave or search the confocal microscopy listserv, go to:
>>>> http://lists.umn.edu/cgi-bin/**wa?A0=confocalmicroscopy<http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy>
>>>> *****
>>>>
>>>> Dear list,
>>>> I'm curious about the effects of reflection off a dichroic mirror and
>>>>
>>> transmission through a high-NA microscope objective on the polarization
>>> state of of laser light. In particular, I want to know how a 1064nm beam
>>> used for optical trapping might be affected, so this is not actually a
>>> confocal question, but I figured that these effects are likely of more
>>> general interest, and that any wavelength-specific issues might also
>>> affect
>>> multiphoton setups.
>>>
>>>> My question is essentially: how do dichroic mirrors and high-NA
>>>>
>>> objectives (mine is a 1.49 Nikon TIRF objective) change the polarization
>>> of
>>> a linearly polarized beam, if at all? Can they induce ellipticity? I've
>>> seen some (usually vague) references to both elements affecting
>>> polarization, but I haven't been able to dig up any papers giving clear
>>> explanations about (a) the underlying mechanism or (b) the magnitude of
>>> the
>>> effects.
>>>
>>>> Regarding the dichroic, it is clear to me that the S and P components
>>>>
>>> will have different Fresnel reflection coefficients given the dielectric
>>> coating. I can see how this would change the ellipticity of an
>>> elliptically
>>> or circularly polarized beam, or slightly rotate the polarization of a
>>> linearly polarized beam (if it were not pure S or P polarization). To
>>> induce ellipticity in a linear beam, there would have to be some phase
>>> retardance induced, which I believe is also possible, but the mechanism
>>> is
>>> not clear. Is this dependent somehow on the angle of incidence as well?
>>>
>>>> The effect of the objective is even less clear to me, as is the apparent
>>>>
>>> distinction between effects of high-NA vs. low-NA objectives. Naively, I
>>> would guess it would arise from birefringence (perhaps induced by stress
>>> on
>>> the internal optical elements?).
>>>
>>>> If anyone can provide any insights, or point me in the direction of
>>>>
>>> informative papers I may have missed, I'd be grateful.
>>>
>>>> Thanks in advance,
>>>> Matt
>>>>
>>>
> --
> Matthew Nicholas
> Medical Scientist Training Program Student
> Laboratory of Arne Gennerich
> Department of Anatomy and Structural Biology
> Albert Einstein College of Medicine
> Forchheimer Building, Room 628
> 1300 Morris Park Avenue
> Bronx, New York 10461
> 718.430.3446
> [hidden email].**yu.edu<[hidden email]>
>