Serial Number Restoration
Faculty Mentor Information
Dr. Rene Rodriguez (Mentor), Idaho State University; and Dr. Lisa Lau (Mentor), Idaho State University
Abstract
When items such as firearms or vehicles are stolen, thieves often file off the serial number. The current methods used to recover the number employ a destructive etching technique where an acid or base solution is placed on the defaced area. This technique cannot be repeated on the same piece of evidence since the etching destroys the remnants of the serial number in the process.
Past efforts have shown promise using heating followed by infrared (IR) image processing. The heating culls out the defaced serial number, allowing IR cameras to detect thermal imprints left by the stamp. This method proves beneficial for trials as it does not rely on the human eye to determine the number.
Further experiments were performed on serial number coupons purchased from a forensic lab supplier which were defaced via file or by machining the numbers off. Once the serial number was recorded, the defaced area was coated in orange or black paint to aid the heating process. The accuracy of the serial number recovery should be affected by parameters which include: laser power/wavelength, pulse duration/frequency, initial temperature of the specimen, and laser beam profile. Preliminary results of these parameters will be presented.
Serial Number Restoration
When items such as firearms or vehicles are stolen, thieves often file off the serial number. The current methods used to recover the number employ a destructive etching technique where an acid or base solution is placed on the defaced area. This technique cannot be repeated on the same piece of evidence since the etching destroys the remnants of the serial number in the process.
Past efforts have shown promise using heating followed by infrared (IR) image processing. The heating culls out the defaced serial number, allowing IR cameras to detect thermal imprints left by the stamp. This method proves beneficial for trials as it does not rely on the human eye to determine the number.
Further experiments were performed on serial number coupons purchased from a forensic lab supplier which were defaced via file or by machining the numbers off. Once the serial number was recorded, the defaced area was coated in orange or black paint to aid the heating process. The accuracy of the serial number recovery should be affected by parameters which include: laser power/wavelength, pulse duration/frequency, initial temperature of the specimen, and laser beam profile. Preliminary results of these parameters will be presented.