The 890DIB25 is a 25 mm diameter Standard Interference Bandpass Filter, specifically designed to transmit light in the 890nm wavelength range while blocking other wavelengths. This filter is sourced from Knight Optical, a reputable vendor known for their high-quality optical components.
The filter is made from UVFS Mal- 1965, a material specifically chosen for its optical properties. It has a base shape of a circle, a standard geometry for optical components due to its uniform distribution of light. The filter's thickness is 6.1mm, providing sufficient structural integrity while minimizing optical distortion.
The 890DIB25 has a cut-on wavelength of 885nm and a cut-off wavelength of 895nm, meaning it begins transmitting light at 885nm and stops transmitting at 895nm. The central wavelength (CWL) is 890nm, the midpoint of the transmission range. This precise wavelength control is crucial in applications where monochromatic light is required.
Both the front and back of the filter are coated with KNI 890DIB, a proprietary coating developed by Knight Optical. This coating enhances the filter's performance by reducing surface reflections and increasing transmission efficiency.
The filter's shape is described as a Thin Lens, indicating it may have lens-like properties. However, without additional information, it's impossible to determine the exact nature of these properties.