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What sort of power are you talking about?  Is a mW per nm 'lots' by the
standards of what you want?

Craig


On Fri, Nov 22, 2013 at 8:33 AM, Judy Trogadis <[log in to unmask]> wrote:

> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> Hi All
>
> This posting of a couple of weeks ago has suddenly become relevant for us.
>
> Does anyone know of a powerful continuous white light source in the
> 600-800nm range? Emphasis on the word 'powerful' because in most light
> sources there seems to be a steep drop in power above 650nm.
>
> Thank you,
> Judy
>
> Judy Trogadis
> Bio-Imaging Coordinator
> Keenan Research Centre, St. Michael's
> 209 Victoria Street
> Toronto M5B 1T8, Canada
> office: 416-864-6060 ext. 77612
> imaging facility:           ext. 77434
> cell:        416-254-9330
> [log in to unmask]
>
>
>
> -----Original Message-----
> From: Confocal Microscopy List [mailto:[log in to unmask]]
> On Behalf Of Ben Freiberg
> Sent: Thursday, November 07, 2013 10:59 PM
> To: [log in to unmask]
> Subject: Re: Brightness difference Hg vs LED
>
> *****
> To join, leave or search the confocal microscopy listserv, go to:
> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> *****
>
> All,
>
> Having been involved in the lighting industry from a commercial standpoint
> I
> wanted to respond to this thread in an unbiased and independent experienced
> voice.
>
> As has been previously mentioned, there are many areas of the spectrum in
> which solid-state solutions have surpassed HBO in intensity at the sample
> plane.  I completely agree with the assessments that there are many
> components that go into building an illuminator and therefore many sources
> of light loss in the systems on the market.  Key to any measurement of
> power
> is how much light is delivered to the sample, so if anyone does take up the
> offer to compare light sources, measurement of mW//cm^2 at the sample plane
> will provide the best indication of the total performance of a light source
> on a microscope.  That being said, one must make sure that the excitation
> filters used with solid-state sources are matched to the peak of the source
> and not simply use off the shelf filters and expect them to perform
> optimally.
>
> There has been mention in this thread of the gaps produced when using
> multiple sources and combining them into a shared collimated beam.  As has
> been stated, in general, increasing the number of input sources decreases
> the overall throughput of light in the system as source combining optics
> can
> be lossy and will cut the overall intensity of any single source that could
> be coupled to the microscope.  One solution that has not been mentioned in
> this thread is the 120-LED from Lumen Dynamics.  The 120 LED overcomes the
> limits of combining multiple sources by using a high intensity white LED
> source.  This product, according to the LDGI website, covers wavelengths
> from 370nm all the way out to 700+ nm with reasonable intensity.  While HBO
> may be brighter at some wavelengths versus the 120-LED, rarely are these
> sources, HBO or solid-state, used at max power especially in live cell
> applications.
>
> I would suggest that the 120-LED be included in whatever tests come from
> this thread as it is a unique product from the standpoint of how the white
> light is generated for fluorescence applications versus the other solutions
> on the market that combine many sources.
>
> As for the overall performance of all solid state products mentioned thus
> far in this thread, one should consider the following: every mid to high
> end
> solid state source produces multiple times more power than 175W xenon at
> the
> sample plane at all wavelengths greater than 360nm and all the way out to
> the NIR.  If anyone has experience using xenon as their primary source, I
> hope this puts the current state of solid-state illuminator intensity into
> perspective.   Bottom line is for most applications, the benefits in cost
> of
> ownership, stability and overall function have the solid-state solutions
> greatly out-perform their HBO counterparts with an additional benefit being
> that solid-state sources are a green solution and they eliminate the threat
> of mercury contamination due to improper disposal or explosion of mercury
> burners.
>
> Ben
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> On Tue, 5 Nov 2013 12:56:42 -0500, Philip Oshel <[log in to unmask]>
> wrote:
>
> >*****
> >To join, leave or search the confocal microscopy listserv, go to:
> >http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
> >*****
> >
> >All,
> >
> >I had this question put to me by a new faculty member, and don't have a
> >ready answer:
> >"Is there a ballpark percentage for how much less bright an LED vs a
> >standard mercury lamp light?"
> >This is for regular epifluorescence, not confocal.
> >
> >This is in the realm of arm-waving over a picture of beer (a good, dark
> >stout), ignoring brands, how old the Hg bulb is, ex/em cubes, which part
> >of the spectrum is used, and all that. Personally, I'd think the answer
> >is more like, "Doesn't matter, the dimmer system is still too bright to
> >use all the available light and not damage the specimen." But ... ?
> >
> >Phil
> >--
> >Philip Oshel
> >Microscopy Facility Supervisor
> >Biology Department
> >024C Brooks Hall
> >Central Michigan University
> >Mt. Pleasant, MI 48859
> >(989) 774-3576
>