Infrared (IR) illumination is used to enable CCTV cameras to produce high quality images under night-time conditions without imposing intensive, obtrusive visible light illumination. The IR illuminators may be equipped to provide light where a distinct red glow warns of the presence of such illumination (Overt illumination) or to provide illumination where only the trained eye can detect the presence of such lighting (semi-covert illumination). In addition fully covert illumination can be provided where it is impossible to detect the presence of the IR light. Envin Scientific prides itself on being able to offer the highest quality of technically efficient sources for all of these categories of illumination.