Day/Night is a popular term for lenses and other products which are optimized for operation in both daylight and low-light conditions using an infrared illumination source. Such products require specialized design and manufacturing techniques to provide good image quality under this broad range of spectral conditions. Using a Day/Night lens under these circumstances can improve focus, brightness and resolution over conventional lenses. Sunex also offers specialized Day/Night filter products which can further optimize your application.

IR-corrected lenses are also very popular in industry outside of security and surveillance. They are sometimes also called RGBIR (e.g., in automotive) or hyperspectral (e.g., medical).

Day/Night Filters

For many camera applications, Infrared (IR) is an unwanted component of the light spectrum and is often blocked using IR cut-off filters that block the transmission of the infrared while passing the visible (VIS). The Sunex IRC4x family of dual-bandpass filters on the other hand are specifically designed to allow the visible and a narrow IR-band to pass through simultaneously. Typical configurations are VIS+850 and VIS+940. Sunex also offers single-band IR filters, and custom filter designs. 

We also offer IR cut-off filter exchanger with an integrated lens mount that allows true day/night (TDN) operation. For daytime operation, an absorptive color filter provides true color rendition. At night, an AR-coated window allows maximum light transmission.