Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Forensic Laboratory Equipment

No description
by

Lorie Poff

on 17 August 2014

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Forensic Laboratory Equipment

Compound and Stereo Microscope
A stereo microscope is used to characterize soil samples, plant parts, glass chards, clothing fibers. A modified type of compound microscope is a petrographic microscope. It uses polarized light to determine object density. These microscopes can magnify objects as small as 10 microns up to 1000 times.


Transmission Electron Microscope

This microscope sends a beam of electrons through a very thin section and can magnify it up to 500000 times. The lab can take a very thin slice of a specimen and determine, for example, the exact time of death. TEMs are used to evaluate trace evidence left at a crime scene.
Photography in the crime lab
Alternate light photography uses lasers and UV light to reveal "hidden" evidence from a crime scene such as latent fingerprints and body fluids. Bone, teeth and narcotics will also fluoresce. CSI labs spray an area with a chemical like luminol to help detect evidence.

The Crime Scene Laboratory

Forensic Laboratory Equipment

Evidence Collected at a crime scene is transported to be analyzed at a crime scene lab

Scanning Electron Microscope (SEM)
SEMs can magnify the surface of solid objects up to 200,000. They are used to evaluate the following:

Gunshot residue analysis
Firearms identification (bullet markings comparison)
Investigation of gemstones
Examination of paint particles
Filament bulb investigations

Handwriting
Counterfeit money
Examination of non-conducting materials (such as fibers)



SEM fly
image

SEM silk fiber

Human skeletal tissue magnified with TEM
latent fingerprint

Ballistics Photography

Much information can be obtained from bullets as they leave residues that may be photographed and analyzed in the lab. Each gun leaves characteristic marks on each bullet, like a fingerprint that may be used to identify a weapon. Ballistics Photography may also be used to determine the distance, velocity, and angle a weapon was fired.

bullet time freeze frame
Ballistics velocity

bullet comparisons
Full transcript