Neutral Density Filters suit visible and near IR imaging.

Press Release Summary:



Suited for imaging at 350-1,100 nm wavelengths, low-reflectivity NI Filters come in 4 optical densities of 0.3, 0.6, 0.9, and 1.2 with overall transmission of 50, 25, 12.5, and 6.25%, respectively. Units feature uniform attenuation simultaneously over entire visible and near-IR range imaged by most industrial CCD/CMOS cameras. Available in 1, 2, and 3 mm thicknesses, filters have reflection-inhibiting vacuum-evaporated protective overcoat that minimizes undesirable back reflections.



Original Press Release:



New Low-Reflectivity Neutral Density Filters for Visible and Near IR Imaging



Palatine, IL: Midwest Optical Systems (MidOpt) has developed a new line of neutral density filters for imaging at visible, near-infrared and near-UV wavelengths (350-1100nm). These "NI" filters are available from stock in four optical densities that range from 50% to 6.25% overall transmission, in ALL popular filter thread sizes, ready for next-day delivery.

Neutral density filters are used to reduce the amount of light reaching the sensor. This allows for longer exposure times and reduced depth of field by using a wider iris opening, thus improving the separation of subject matter from the background.

Unlike absorptive filter glass and non-reflective neutral density filters, the low-reflectivity NI filters from MidOpt feature uniform attenuation simultaneously over the entire visible and near-IR range imaged by most industrial CCD/CMOS cameras, with the actual percent transmission (or optical density) remaining constant.

Uniform transmission over an extremely broad spectral range

These filters also feature a reflection-inhibiting vacuum-evaporated protective overcoat that is designed to reduce undesirable back reflections while maintaining uniform transmission over an extremely broad spectral range. Compared to absorptive neutral density filters, MidOpt's NI Filters use a low expansion glass substrate material to enhance durability and resistance to temperature extremes and thermal shock at no additional cost.

Optical densities in the new NI Filter line include NI030 (OD = 0.3, 50% transmission), NI060 (OD = 0.6, 25% transmission), NI090 (OD = 0.9, 12.5% transmission) and NI120 (OD = 1.2, 6.25% transmission).

NI Filters are available off-the-shelf in standard threaded mounts, in thicknesses of 1, 2 and 3mm, and in custom shapes and sizes. Typical custom applications include reducing transmission from broadband light sources, low power laser attenuation and partial shrouding of inspection applications. Lead times for custom manufactured components are approximately one week.

These filters are only one of many image-enhancing tools available to vision system integrators and process engineers from Midwest Optical Systems. Please contact the MidOpt Team for a quotation or for any further technical information that may be desired.

In the US, contact:

Midwest Optical Systems, Inc.

322 Woodwork Lane

Palatine, IL 60067 USA

Phone: 847-359-3550

Fax: 847-359-3567

Email: info@midopt.com

Web: www.midopt.com

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