# Why Do Police Use UV Flashlights? UV flashlights reveal hidden evidence in criminal investigations. - **Source:** [SlashGear](https://www.slashgear.com) - **Published:** 2026-08-11 - **Topic:** [Business](https://brifing.si/c/business) - **Original article:** - **On Brifing:** https://brifing.si/s/3d199fac-bb47-48f8-8933-9bd46fbe34a5 ## Basic Function of UV Flashlights UV flashlights use ultraviolet wavelengths to make objects and residues more visible. These devices can reveal evidence that is otherwise missed under normal lighting. Fingerprints, footprints, and other materials become prominent under UV light due to fluorescence. This plays a critical role in criminal investigations. ## UV as an Alternate Light Source UV flashlights fall under the category of Alternate Light Sources (ALS) and are frequently used in forensic investigations. They enable detailed scanning of crime scenes. However, UV flashlights alone are not sufficient; additional tests and analyses are needed to support the evidence found. ## UV Imaging Equipment Police also use UV imaging equipment alongside UV flashlights. Specialized cameras and filters capture materials that reflect UV light or fluoresce. These techniques help preserve details that traditional photography might miss. ## Examining Currency Security Features UV flashlights are used to examine security features in U.S. currency. Bills of $5 and higher contain embedded security threads that glow a specific color under UV light. This speeds up counterfeit detection and aids law enforcement. ## Risks of UV Light Prolonged use of UV flashlights can be harmful to skin and eyes. Unprotected skin can suffer damage, and eye discomfort may occur. Therefore, both police and consumers must take necessary precautions when using UV flashlights. ## Other Uses of UV Technology UV technology is also used in cameras that simulate animal vision. This plays a significant role in biological research and the study of natural habitats. UV light reveals details that the human eye cannot perceive. ## Household Use of UV Flashlights UV flashlights are also handy in household settings like homes and garages. These devices are ideal for finding lost items or detecting stains. However, potential risks of UV light should be considered even in household use. ## Importance of UV Flashlights UV flashlights are a critical tool in criminal investigations. They uncover hidden evidence, contributing to the justice system. However, caution and necessary precautions are essential during their use. ## Sources covering this story - https://www.slashgear.com/2231223/why-do-cops-use-uv-flashlights-overview/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._