NEV0830M In Stock

The NEV0830M by ThorLabs is a high-quality variable absorptive neutral density filter that is designed to provide an optical density (OD) ranging from 0.8 to 3.0. This filter is perfect for applications requiring low power.

The NEV0830M is composed of two NG5 Schott Glass prisms, which can be easily translated using the adjuster knob located on the side of the housing. By adjusting the position of the prisms with respect to each other, the amount of substrate through which the beam travels can be varied, thereby changing the effective OD of the filter. Rotating the adjustment knob clockwise yields a larger OD, and the prism position indicator located on the front of the housing moves to the right as the OD increases. Each tick mark on the indicator corresponds to a 0.2 change in OD.

The NEV0830M has a clear aperture of Ø10 mm. However, since the beam will be displaced horizontally by 1.5 mm, it is recommended that the input light beam should be Ø8.5 mm or smaller. When the beam enters through the front of the filter, it will be displaced to the left. The anodized aluminum housing of the NEV0830M measures 4.97" x 1.03" x 1.76", not including the adjustment knob. It can be mounted on a Ø1/2" post using the 8-32 tapped hole on the bottom. For those who prefer to use a metric post, a compatible AS8E4M 8-32 to M4 adapter can be used to mount the filter on a metric post. Additionally, the NEV0830M can be integrated into a 30 mm cage system with the four 4-40 tapped holes on both the front and back of the housing. The aperture on each side of the housing is SM05 (0.535"-40) threaded for compatibility with Ø1/2" lens tubes.