The purpose of this technology transition workshop is to provide the student with the history and evolution of latent fingerprint evidence detection through luminescence, beginning with the introduction of the argon laser in 1977. Early challenges to implementation of this technology (including cost, training, maintenance and paradigm shift) will be discussed. Landmark cases and their implications will be reviewed. This class will include lecture, demonstration, and hands-on activities to illustrate the concepts presented.
The different kinds of Forensic Light Sources will be discussed and demonstrated on a range of sample types using popular detection chemistry. The importance of exciter, high pass barrier, and narrow band pass filters will also be discussed and demonstrated.
Photography issues specific to luminescence will be highlighted. In addition, the strengths and limitations of each Forensic Light Source will be demonstrated and discussed, with reference to versatility, sensitivity, manpower issues, cost, maintenance, and laboratory versus crime scene applications.
At the completion of the Latent Fingerprint Image Enhancement Technology Transition Workshop, the participant will acquire the knowledge to:
- Understand and put in context the history, expansion and significance of latent fingerprint evidence detection through luminescence
- Explain, problem solve and troubleshoot the basic physics of each light source, including:
- How argon, frequency-doubled YAG, and semiconductor lasers work
- How a filtered lamp works
- How an LED works
- Understand and explain the advantage in sensitivity of luminescence over absorption/reflection detection
- Conduct light examinations on different types of evidence with different Forensic Light Sources
- Photograph fingerprints, fibers and/or body fluids using a digital SLR camera
- Understand and use high pass and narrow band pass filters
- Make an informed decision on acquisition of a Forensic Light Source