Why the Leica DVM6 digital microscope makes forensic investigations more efficiently
The Leica DVM6 digital microscope has a 16:1 zoom and three objective lenses which cover a magnification range of 12x to 2,350x. The objectives, seen below, can be changed quickly and easily, as shown in this video.
The microscope head of the Leica DVM6 can tilt eucentrically from –60° to +60° and the sample stage can rotate from –180° to +180°. Users can both tilt the head and rotate the stage with just one hand. In addition to the integrated LED (light-emitting diode) ring light and coaxial illumination, there is also the possibility to install a spotlight (Leica LED5000 SLI) and transmitted light (BLI) illumination. The motorized stage of the Leica DVM6 allows extended depth of field (multi-focus) images along the vertical (Z) direction and stitching of images along the horizontal (XY) direction. Even the combination of XY and Z stitching is possible and allows larger fields of view with high Depth of Focus and 3D modelling. A bullet holder made especially for the Leica DVM6 to perform forensics investigations is shown in Figure 7.
Firearms and tool marks
The entire cartridge can be imaged with the Leica DVM6 when using features like XY stitching and the Extended Depth of Field (EDOF), making it easy and fast to get a large overview, high quality image of the cartridge sample analyzed. Images from the Leica DVM6 of bullets after being fired from a firearm are shown below.
Counterfeiting/forgery: money, credit cards, documents, and identification
Analysis of money, credit cards, documents, and identification cards can be done quickly with the Leica DVM6 due to the 16:1 zoom range, versatile integrated illumination, and one-handed tilting. Images from the Leica DVM6 of paper money, a credit card, and an identification card are shown below.
When analyzing money, forensics experts can change quickly from an overview to visualizing fine detail using the zoom optics of the Leica DVM6. Below are overview and zoom-in images showing fine details on paper money recorded with the Leica DVM6.
Forensics experts can easily see more detail when using the versatile integrated illumination of the Leica DVM6. The holographic image (pigeon) of a credit card was illuminated with the ring light of the Leica DVM6.
As the illumination cycled through each of the ring light LED segments, four images were recorded and captured in this video.
With one-hand tilting, users can focus on the displayed image and finding what is needed during the analysis and not on the sample stage or microscope head.
Images of a security hologram on a Swiss Identification card recorded with increasing tilt of the Leica DVM6 microscope head are shown in the video and the table below.
Documents: Analysis of crossing lines
Determining the sequence of crossing lines is one of the most challenging problems for forensic examination of documents. Currently, there is no standard method for this type of analysis. To distinguish which crossing line was made first on a document and which one second, the Leica DVM6 offers an easy and reliable solution for examination of intersecting markings on a document.
With multiple built-in lighting methods, such as ring light and coaxial illumination Leica DVM6 users you can determine cleary and quickly the order in which crossing lines were made on a document. The integrated illumination allows the sequence of lines over and under toner markings (printer), lines over and under stamp markings, and stamp markings over and under toner markings to be identified. For the full picture, the tilting function of the Leica DVM6 allows users to further view the crossing lines from various angles.
Summary table showing which features of the Leica DVM6 are useful for certain forensic analyses . An X means the feature is "useful" for the particular analysis and an (X) means it is "likely useful".
|Low objective||Middle objective||High objective||Integrated ring / Coaxial light||Spotlight (Leica LED5000 SLI)||Transmitted light (BLI)||Tilting||Rotating||Extended depth of field (infinite focus)||X-Y stitching (scan)|
|Leica DVM6 S||Z image builder||XY image builder|
|Leica DVM6 A||Montage||3D models||Mosaic|
|Locks & cylinders||X||X||X||X||X||X|
The results reported here show that forensic analysis of evidence from ballistics, paper money, credit cards, and identification cards can be obtained efficiently with the Leica DVM6 digital microscope.
The fast workflow is due to the Leica DVM6’s many practical features, such as a convenient way to change magnification rapidly over the full range, tilting, sample rotation, and versatile illumination. Faster workflow efficiency leads to fast data acquisition and analysis for forensics.
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- Leica DVM6 Internet Product Page. Technical Specifications.