The Tabletop SEM and Forensic Science

30 Jan

My guest bloggers today are the ASPEX Team and they will discuss the Scanning Electron Microscope (SEM), a valuable forensic science tool. They also have a unique and fun offer for you. Want to know what things look like under the SEM? Maybe something in your own home? Now you can find out. Check out their site for some fun images and then if you want send them an item you want to scanned.

Ever wonder what something looks like up close? Really close? Most people have seen objects under a standard optical microscope, but few have seen what something looks like under a more powerful magnifying instrument: a scanning electron microscope (SEM). 

In forensics, crime scene samples are often very minute and difficult to decipher. SEMs provide verifiable evidence to the source of an object. These microscopes have the ability to reveal an item’s true topography and have become one of the primary methods in making arrests and defining crime scenes in the industry today. Items such as fibers, gun-shot residue and fingerprints are just a few of the many things that have been analyzed with a scanning electron microscope.

ASPEX, makers of the Personal Scanning Electron Microscope (PSEM), do not limit their analysis to only a microscope; rather, their packaged software allows the investigation to be viewed on a computer with different types of reports and tests available with the click of a mouse.

This, however, is only scratching the surface of all of the different ways scanning electron microscopes can influence the field of forensics and other areas.
In fact, ASPEX recently kicked off their “Send Us Your Sample” campaign, encouraging forensics professionals, science geeks, educators, students and anyone else who wants to send in samples to be scanned by an ASPEX tabletop SEM.

The PSEM has a scan range of 100nm to 5mm and an imaging resolution of 25nm, capable of bringing the smallest samples into focus. ASPEX will scan submitted samples and then post before/after photos along with an analytical report online. This allows viewers to see what the sample looks like to the naked eye as well as under the PSEM.

The SEM Image Gallery shows the samples already scanned, including mold, cat hair, fly eyes, an old toothbrush and more. Anyone interested in having an item scanned can simply fill out the submission form and send in a sample for analysis, free of charge.

The ASPEX Team

Thanks guys for being my guest today.



3 responses to “The Tabletop SEM and Forensic Science

  1. Craig Faustus Buck

    January 30, 2010 at 1:57 pm

    Very, very cool!


  2. Wally Lind

    February 5, 2010 at 8:10 pm

    I assume this device is used in the crime lab, and not in the field or police station. I also assume that it is used to detect and compare morphology. Is it used in any other way?


    • D.P. Lyle, MD

      February 6, 2010 at 10:10 am

      Yes, it should function just as a larger SEM and be used to compare materials such as GSR, paint fragments, fibers, etc. It seems to be simply a smaller version of the larger ones.



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