The laser system has a rigidly built steel frame box, into which the laser, laser cavity gasses, power supply, beam line optics, and computer are held. Although the laser box is on wheels, these are usually locked to reduce the chance of optical misalignment. This page reviews the basic construction of the laser itself. If you are trying to figure out what is wrong with a broken system, It’s probably best to have some idea of how it’s put together.
This is the empty steel frame as it came out of the shipping crate. Under the white shelf go the laser cavity gasses, above it the laser. On the top will go the camera, some laser optics, computer, and sample chamber. The white thing in the back-right of the frame with a hole (port) in it is part of the beam line and optics.
These two tanks are mounted in the frame bottom compartment. They have the gasses used to maintain the laser cavity. The argon/fluorine gas is called “premix” in the ESI/Coherent literature. They are a bit cagey about what the mix is, but it’s something like 0.1% fluorine, 5% argon, and the rest helium. Let me know if you find more accurate information.
Inside the laser frame. Red arrow points to the port through which the laser beam enters the beam line from the laser head.
Here, the laser box has been installed, with the laser head snout fitted to the beam line port indicated in the previous image. The snout is on what I would call the laser box front.
This is what I would call the laser box back, containing the laser power supply and other electronics, communications ports, on-off switches, and connections for helium and argon/fluorine gas lines (circled in red).
Inside the beam line box, shown above, with various parts labeled. This takes the horizontal beam from the laser, and reflects it upward (mirror), through a filter, the shutter, and the beam splitter that controls pulse power.
This is the beam line port at the the top-back of the laser frame. Inside the aluminum box are the right mirror, shutter, and laser power control beam splitters. This is the aluminum box in the image above.
This shows the lower part of the optics and stage box that sits above the original steel frame. It sits on top of the white steel plate. This shows the beam pipe that transfers the beam from the aluminum box shown above, up to a mirror in the optics and stage box.
This is the back of the box, the stage is at the opposite end.
The beam line and electronics in the upper part of the optics and stage box. The aluminum box seen here is another part of the beam line, which needs to be kept purged with dry nitrogen.
The objective box is a cover for some of the hardware seen here to the lower-right, and is not in its final position. It will be moved to the lower-right, where the beam line is directed down with a 45° mirror (inside black beam pipe, lower-right).
Here the top is on the beam line box. The objective box cover is still out of its final place. Eventually it will go on the far end of the beam line box.
This is where the stage and objective lens are. The 45° angle box at the top center is part of the camera optics, which looks down through the transparent-to-visible-light laser beam mirror below. The laser beam comes in under the camera system. The objective box cover hides everything above the orange laser safety shield.
This is a view you don’t normally have, with the stage chamber top off. The top never comes off except to repair broken parts. Not shown here is a sub-tray LED lamp that can illuminate thin sections from underneath. It plugs into the back of the stage housing, and is cantilevered over the black center part of the stage top, and under the sample tray.
Here’s the lamp, installed. There’s a special tool to install or remove the lamp once the stage housing top has been installed.
There are two windows that the objective lens can look through. This is the analytical window. It has a relatively large working distance and large gas volume above the sample. Helium is fed from the stage housing below, up over the sample, and out the hose indicated that goes to the ICP-MS. Washout time is relatively slow.
This is the imaging window. It has a small working distance inside the stage, and a small gas volume above the sample. Instead of helium being supplied from the main stage housing area below, helium is fed across the the area between the window and sample through two thin green PEEK tubes.
This shows the green PEEK tubing that goes to the ICP-MS from the imaging window. The tube threads through a stainless steel pipe, to fit into an O-ring fitting in the side of the window assembly. There is an identical helium inlet PEEK tube on the other side of the stage housing.
This is the whole thing, assembled. It is set up as shown here using the analytical window, which you can tell because the white tube is in place to carry helium and sample to the ICP-MS.
