Saturday, March 3, 2012

Bausch and Lomb Mercury Arc UV source and monochromator

This is a Bausch and Lomb High Intensity Monochromator with an SP-200 UV Mercury arc source.

Monochromator is catalog # 33-86-75.  Grating has 2700 lines / inch.

Operating, output set to 170nm, flash photo

 Lamp operating full intensity, output set to 300nm
 Output set to 300nm
 Operating full intensity 300nm
 Power supply SP-200
 Power supply SP-200
 Interior of source, showing lamp and choke assembly
Choke / concentrator has quartz optics, two elements
to concentrate beam from Lamp.
 Closer up to Lamp
Lamp envelope.  arc starting electrode is
on opposite side of the envelope.  There is only
the high voltage connected to the top and
bottom.  Other arc starting electrode on
opposite side has no connection, but is
open to air to allow arc at lower starting
voltage (I think)


  1. Hi Jim,

    We have a SP-200, just like yours, but without lamp... we tried an HBO 200W/2, but had no success in starting it. I would very much appreciate if you could have a closer look at the lamp and tell us what which type you have in your illuminator.

    Thanks so much!


  2. Hi Jim,
    We have the same system but somebody took out the lenses. Can you please estimate what is the focal length of yours? They are easily demountable...

  3. Hi, thank you for posting this setup. I have a B&L Sp-200 mercury power supply. I'm still looking for the other part that connects to it. I'm not sure if I remember if I have it or not. I don't remember it looking like what you have though. What exactly is a mercury power supply anyway? I noticed that the monochromator you have is not the same battleship gray of your SP200? My SP 200 is battleship gray and looks just like your unit. The output takes a rectangular 4 pronged affair to plug into it. Is yours set up the same way? The monochromator was a plug and play unit having the same rectangular 4 pin male connector cord "plug-in"?

    How does one use what I assume is dangerous UV emission spectrum light with a microscope without trashing your eyes in the process of viewing a sample?


    1. I suspect the arc lamp needs a starting voltage with higher voltage than the idle running voltage. The supply will provide an extra potential till the current draw on the main supply comes up to indicate an arc has started.

      There were two series of Bausch and Lomb monochromators. The older ones you refer to date to the 50's I think. I wish I could get one of the older Fisher catalogs with the B&L line to have all the options. The older series had a dial display to select the NM setting for your output.

      A newer series with a digital mechanical dial indicator with 4 digits came out later. I have also seen these badged as EG&G and they are identical inside to mine.

      You can swap the top grating to select from 3 different bands, near as I can tell. Some people on eBay advertise these as monochromators, and have no idea they are an option.

      I have a full set of 3 for both types of bodies.

      I have the Tungsten and Mercury Arc in this style. Since I also have the Deuterium supply and source here
      You can see that the power supply seems to be of the same vintage for both light sources. The connector style (Berg?) didn't change. I took a photo of the Deuterium supply connector. I believe it is the same style on the Mercury supply.

      As to operating these supplies I'm aware of the dangers of operating these. We had not only these in the lab for fluorescent research, but also a mercury source normally used for UV plastic curing which was probably 100 times as intense. Scared the bejesus out of me to be around that thing when it was running.

      We had a system which used rhodium fluorescence to work. So you would zap the chemical chamber (in a quartz windowed .25 cc chamber) and out the other side we had a very dense 1.5nm wide optical notch filter.

      It was dense enough you could hold it up naked eye to the sun and see almost nothing. it was in the green region and as a result safe for naked eye. The UV was all kept under a heavy black opaque cloth shroud, and a metal box, and everyone in the lab wore special UV eye protection. We also avoided skin exposure to the intense source.

      Also we used a camera, (Photometrics Coolsnap K4) to digitize and analyze the data from the chamber.

      It is for sale here, BTW.

      I've been working on the K4 cameras for a while and am refurbishing several of them. The one in the auction has near zero hours on it

  4. I found the light source device that goes to my SP 200 Mercury Power Supply. It does not look like the one you have pictured. It has a similar looking bulb though. I think some of the optical assembly's components (after the bulb) on mine are different from what you show.

    Is there some sort of I.D. description code stamped onto one end of the bulb that I can use to determine which halogen is used inside the bulb?

    Would you like for me to send you a digital image or two of the unit I have?

    I cannot find a model number or a "descriptive name" for this device printed anywhere on it, just B&L and a caution statement about reading the instructions (dangerous UV radiation emitted).

    Do you have any idea where I can find some instructions for how not to use this device? I don't want to play around with this unit until I have been properly informed as to how it can maim, burn or kill me first.