CCTV lenses are specialized lenses designed for use with closed-circuit television (CCTV) systems. These lenses are used to capture high-quality images and video in security systems, surveillance applications, and other situations where a reliable, high-quality image is required. CCTV lenses are available in a range of focal lengths, from wide-angle lenses that can capture a large field of view to telephoto lenses that can zoom in on distant objects. They are also available in different apertures, which control the amount of light that enters the lens and affects the depth of field. Some common types of CCTV lenses include: Fixed focal length lenses: These lenses have a fixed focal length and cannot zoom. They are often used in applications where the camera is set up to capture a specific area, such as a door or window. Varifocal lenses: These lenses have a variable focal length and can be adjusted to zoom in or out. They are often used in applications where the camera needs to be adjusted to capture different areas over time. Zoom lenses: These lenses can zoom in or out to capture different areas. They are often used in applications where the camera needs to be adjusted to capture different areas over time, but the lens cannot be physically moved. Fisheye lenses: These lenses capture a very wide angle of view, often up to 180 degrees. They are often used in applications where a very wide field of view is needed, such as in a large room or open area. Overall, choosing the right CCTV lens depends on the specific application and the requirements of the camera system. Factors such as focal length, aperture, and image quality should all be taken into consideration when selecting a CCTV lens.