Opto Sigma

• Convenient for adjustment of beam intensity
• Optical density from 0.4 - 2.7
• 2-inch and 4-inch diameters
• May be post mounted

Neutral density filter wheels are convenient tools for the adjustment of beam intensity. They can be mounted in an optical path and rotated to increase or decrease the beam attenuation. Since the filter coating is neutral over the visible spectrum no change of spectral content will occur. The filters have a 0.04 - 2.7 variation in optical density over 330 degrees of rotation so they can be used to balance signal strength over a wide dynamic range (10,000:1). The outer metal ring is grasped and rotated by hand to set the density level. A clamp screw enables the rotation to be locked at any point. The central boss has three different threaded holes (8-32, M4 and M6) to accommodate post or pedestal mounting for both inch and metric mounting systems. Two types of discs are offered - BK7 and synthetic fused silica. The two sizes offered cover most applications.