Some Points to Consider When Adding an Automated Stage to a Microscope

The Added Distance on Upright Microscopes

There are a number of issues that must be considered whenever you add any automated scanning stage to your microscope. Since nearly all of the major microscope manufactures design their microscopes to work with manual stages that are thinner than automated stages there are a couple of issues that must be addressed. First, you will add distance between the condenser and the bottom of the slide on any upright microscope. This is simply a fact and there is no getting around it. How much distance you add is dependent upon the stage but any of the quality units are going to add about 0.70 to 1.0" to the top of the stage. If the stage plates are thinner than this then they may flex, or warp, excessively with changes in temperature. Because the stages add distance between the slide and condenser the condenser carrier must be able to move the condenser up this added distance, however nearly all the microscope manufactures to not allow for this. To over come this problem there are two obvious solutions: either move the condenser up or move the slide down. There also is a third solution that is comprised of a combination of the above.

Since there are many different condenser configurations, nearly as many as there are different microscope configurations, it is impossible to come up with a catch all solution. In addition to this each of the solutions mentioned presents some limitations and restrictions. For example, if you have a large DIC condenser it may not fit up through the microscope's stage carrier when you try to raise it up, or if you lower the slide down it is no longer flush with the top of the stage so loading the slide may become more time consuming if you are screening a large number of samples. A number of these points may or may not be actual issues depending upon the users personal preference, but suffice it to say there are issues involved and we here at ASI have gone to great lengths to offer a wide range of solutions to these issues.

First off, all of our upright stages have a very low profile that only add a distance of ??? between the slide and the condenser. The stages are also machined out of jig cast plate that has specific metallurgical properties that prevent it from warping. We have also designed special condenser extenders that go in between the condenser and the carrier to raise the condenser up if needed. In addition to this we have also designed a number of different slide inserts for Upright and Inverted microscopes. We have listed the condenser extenders that we offer in the Microscopes Supported section, and also have attempted to show what we feel is the best solution for the microscope shown. However, due to the number of variables involved, including the users personal preference it may be best to contact us directly so we can propose the best solution for your individual requirements.

Here are a few of the solutions that we have come up with:

1. On some microscopes, such as the Zeiss Axioplan the screw that secures the condenser to the carrier "bumps into the microscope and will not allow the condenser to be move up.
   
   ( Solution) We have designed a replacement screw for this condenser that prevents this from happening.



2. If you use too low of a slide insert to lower the slide down towards the condenser then on some scopes such as the Zeiss Axioplan the longer high powered objectives may scrape against the side of the insert as they are rotated into place. Since these objectives are spring loaded they will not be damaged, however when you hear a $10,000 objective scraping it is a very unnerving sound.
   
   (Solution) Use a combination of a condenser extender and a slightly higher insert such as our SIR-100-HR.



3. On some condensers there is a lens that can be flipped in and out of place. If the condenser is racked up all of the way you may or may not be able to move the lens depending upon its size etc..
   
   (Solution) Either rack down the condenser a bit, move the lens, and then move it back to a predefined stop so that the condenser is still in focus, or use an insert that lowers the slide down far enough to allow the lens to clear.

These are just a few of the solutions that we have documented. Since there are so many variables coupled with the sheer number of different condensers out there, many which are no longer manufactured, we also are willing to do custom designs for specific applications. Of course, the custom design route would require that we get the condenser from the customer to design a custom solution / adapter for it.