13-091 12.5 mm Dia. Hoya ND-0.3 Absorptive Neutral Density Filter; OD 2.5 425-675nm

The 13-091 is a 12.5 mm diameter Neutral Density Filter, sourced from the reputable optical components vendor, Edmund Optics. This filter is designed with a base shape of a circle, making it universally applicable in various optical systems. The filter's primary function is to reduce the intensity of incident light without altering its color composition, thus maintaining the color fidelity of the optical system.

The filter boasts an Optical Density (OD) of 2.5, which corresponds to a transmission of 0.45%. This high OD value ensures significant light reduction, making it ideal for high-intensity light applications. The filter's spectral response is within the visible light range, specifically between 425nm and 675nm, making it suitable for applications where visible light control is required.

The filter is constructed with a thickness of 2.5mm, providing sufficient mechanical strength while maintaining minimal optical path deviation. The front and back surfaces of the filter are coated with the EDM 13-091 coating, which enhances its performance and durability. The filter's overall design follows a Thin Lens shape, ensuring easy integration into various optical systems.