Focus On Focus
It’s not often that the security industry is presented with a completely new imaging technology – one that provides system designers, installers and users alike with a unique feature set that delivers improved efficiencies across the board. New pan focus technology is of great significance since it allows video surveillance cameras to focus on every object in the camera’s field of view, despite distances. In addition to the improved identification capabilities from the expanded depth of field, no manual focus adjustments are required, which allows pan focus cameras to provide extended coverage.
Before the development of pan focus technology, it was generally unpromising to achieve high resolution imaging with a large depth of field for video surveillance applications. That was the technological challenge that Sanyo worked to overcome by developing a unique lens that offers high resolution together with high picture quality. It was Sanyo’s development of deep focusing techniques and unique digital signal processing (DSP) capability in the camera itself that makes it possible to take the original image provided by the lens and apply sharp focus to every object in the frame. This innovative integration between the lens and the camera provides pan focus cameras with 520 lines of resolution and extreme depth of field.
Varifocus Lens vs. Pan Focus LensTraditional varifocal lenses have some well-known weaknesses. With a varifocal lens, objects in front of and behind the main focus point appear blurred. Pan focus compensates for this problem by keeping all objects in focus no matter the distance between the object and the camera lens. This is a clear benefit to the security market because sharper images of more expansive coverage areas can be produced, avoiding the need to cross-shoot multiple cameras.
Typical varifocal lenses have a shallow depth of field, which prohibits the unit from offering useful images outside certain areas of a scene. With its greatly enhanced depth of field, pan focus technology provides video analytics with a more detailed canvas area, resulting in enhanced functionality versus systems with typical cameras.
Additionally, manual focus adjustments are unnecessary with pan focus technology to attain uniform focus of a scene, yet it is still possible to remotely zoom in on specific objects in the frame to capture a specific ID shot. Some units have an integrated PTZ mechanism, while other cameras feature an optional camera control unit to operate the remote zoom feature. With all objects in focus, it becomes easier for security personnel to monitor images and identify situations that may require action. It also makes identifying individuals, vehicles and other objects within a scene easier. One pan focus camera can often replace multiple cameras. Some pan focus cameras integrate RS-232/UTP functionality; other units offer integrated IP control as well.