For this UV video, the subject is illuminated directly by UV emitting lamps . UV filter is placed on the lens, which allows ultraviolet light to pass and which absorbs or blocks all visible and infrared light. UV filters are made from special colored glass and may be coated or sandwiched with other filter glass to aid in blocking unwanted wavelengths.

https://www.youtube.com/watch?v=-6TfuDZdgYw