Ridge Tracing
Definition
For whorl patterns: following the ridge issuing from the inner side of the left delta toward the right delta and recording whether it passes inside (I), outside (O), or meets (M) the right delta. The result contributes to the Henry formula's whorl sub-classification.
- Applies to
- Whorl patterns
- Start point
- Ridge issuing from the inner left delta
- Outcomes
- Inside (I), outside (O), or meets (M)
- Use
- Henry whorl sub-classification
Common questions
What does an outside (O) tracing result mean for whorl classification?+
It means the traced ridge passes outside, or below, the right delta point before continuing, as opposed to entering inside it or meeting it directly, and this outcome is recorded as part of the Henry sub-classification formula for whorls.
Why is ridge tracing only applied to whorl patterns?+
Loops and arches lack the two-delta structure that ridge tracing depends on, since the method specifically follows a ridge between the left and right delta points that only whorl patterns contain.
Related terms
- ACE-V
- Analysis, Comparison, Evaluation, Verification: the four-stage method for latent print examination used by accredited forensic fingerprint laboratories. Analysis examines the latent in...
- Arch
- A fingerprint pattern in which ridges flow across from one side to the other without recurving and without enclosing a central area....
- Core
- The approximate centre of a fingerprint pattern. In a loop, it is identified as the innermost recurving ridge's peak or the tip...
- Delta (Triradius)
- The point of convergence of three ridge systems in a loop or whorl, visible as a Y-junction or triangular confluence. Loops have...
- Henry Classification System
- The fingerprint filing and retrieval system developed by Edward Henry with Haque and Bose in Bengal in the 1890s and adopted by...
- Level 1 Detail
- In ACE-V, the broadest level of information extracted from a fingerprint: the overall ridge flow and pattern type (arch, loop, whorl). Level...
- Loop
- A fingerprint pattern in which ridges enter from one side, recurve, and exit on the same side. The most common pattern type...
- Ridge Counting
- For loop patterns: the number of ridges crossing an imaginary straight line drawn from core to delta, excluding the core and delta...
- Whorl
- A fingerprint pattern in which at least one ridge makes a complete circuit around a central area, or forms a related closed...