45-577 20 mm Dia. N-BK7 Precision Protective Flat Window; t=3 mm Uncoated

The 45-577 is a 20 mm diameter N-BK7 precision protective flat window, with a thickness of 3 mm and no coating. This window is sourced from the reputable vendor, Edmund Optics.

As a flat window, this optical component is designed to protect other optical elements from environmental hazards such as dust, dirt, and moisture, without significantly altering the optical path. Its base shape is circular, making it suitable for a wide range of applications that require a centrally symmetric optical axis.

The window is made from N-BK7, a popular borosilicate crown glass known for its excellent optical properties. This material is characterized by a low coefficient of thermal expansion, making it resistant to thermal shock. It also has a high Abbe number, indicating low chromatic dispersion, which is beneficial for achromatic designs.

The window is uncoated, meaning it does not have any anti-reflective or other coatings. While coatings can enhance the performance of an optical component, they also add to the cost and complexity. An uncoated window is a simple, cost-effective solution when the requirements for transmission and reflection control are not stringent.

The window is designed for a wavelength of 587.6 nm, which is the green line in the visible spectrum. This makes it suitable for applications that use green light, such as some types of fluorescence microscopy.