13-152 12.5 mm Dia. Hoya ND-25 Absorptive Neutral Density Filter; OD 0.6 600-1050nm

This is the 13-152 Neutral Density Filter from Hoya, available through Edmund Optics. It is a circular filter with a 12.5 mm diameter and a thickness of 2.5 mm. The filter is designed to reduce light intensity without altering the color balance of the incident light, making it ideal for applications where excessive light might cause overexposure or other issues.

The filter has an Optical Density (OD) of 0.6, which corresponds to a transmission of 32% (1/√10) for light in the 600-1050nm wavelength range. This makes it suitable for use in near-infrared (NIR) applications. The OD value is a logarithmic measure of the filter's ability to reduce light intensity, with a higher OD indicating a greater light reduction.

The filter features absorptive coatings on both the front and back surfaces, identified as 'edm 13-152'. These coatings are designed to provide the specified neutral density while minimizing unwanted reflections and scattering. The filter's geometry is shaped as a thin lens, which can be beneficial in certain optical systems due to its reduced thickness and weight.

The catalog number for this filter is 13-152, and it can be found on the Edmund Optics website at https://www.edmundoptics.com/p/06-od-125mm-dia-nir-i-coated-absorptive-nd-filter/44435/. According to the provided information, the link is valid and the filter is in stock.