ASTROHN Technology LTD produce lenses for security cameras with resolution up to 8 MP. Pride of place of developed and produced objectives goes to optic schemes of objectives formerly produced for photo cameras: Helios, Industar, Rubinar. Lenses used with CCD matrix are optimized for required resolution because the prototypes’ photographic quality surpasses by far the lenses’ required resolution for CCTV use. The film’s grain at the molecular level demanded better quality and bigger camera resolution than any other multipixel modern CCD camera matrix. Reducing the FOV to 1/4″ also conduced to simplifying the optical schemes versus the 36 mm photographic lenses. With that in mind, lenses produced by our company have required resolution, which in most times exceeds capabilities of cameras our customers use.
When using and engineering the CCTV we recommend using the lenses with fixed focus. Fixed focus eliminates the possibility of tuning camera by the viewing angle and amplification directly on the secured facility at the survey area. However tuning and correction of focal distance of the lenses is performed only once during the camera mounting. In the future during the service life there is no need in varifocal lenses. Varifocal lenses are more expensive and have many drawbacks that are manifested at the large resolutions when the clearness and sharpness along the high contrast are needed. As a result, camera with bigger resolution gives blurred gray image while attempting to maximize. Varifocal lenses in the whole focal distance range do not work in the same manner. Usually manufacturers use the number of megapixels as a resolving power at a minimal focus characteristic. When focus changes, lenses contrast and luminosity characteristics can suffer significantly. Hereby the delineators’ inability to estimate the field of view angularly and chose the suitable lenses leads to the camera/lenses pair exploitation suffer.
All of our lenses are made from optical flint of domestic production. The lenses’ bodies are made from metal alloys.
ASTROHN lenses identification structure
ASTROHN – X1X2-Y1/Y2
|В||Variable focal length (varifocal) of manual setting|
|З||Variable focal length of automatic unit|
|Р||Manual septum control|
|А||Automatic septum controlled by DC|
|В||Automatic septum controlled by Video output|
|У1||Minimum focal length (approximated to mm)|