MFND/MFNDU Reflective Neutral Density Filters-Mounted
- Reflective ND filters are one of simple beam attenuators to be used to control the amount of light.
- These products are mounted in adapter ring for filter holder and useful to use our filter holder products.
- The amount of incident light is controlled by the thickness of the chromium coating.
- There are two types: for visible and for UV.
- A part of the light is transmitted, and the rest is reflected or absorbed by the coating.
- They do not affect the colors as wavelength dependence is a little and neutral optically.
Attention
- The transmittance curves are based on actual measurements and may be different with manufacturing lots.
- They will not be recommended to use with semiconductor laser which will not be stable of its laser by backing light. Absorptive ND filter would be applied for it.
- Be sure to wear laser safety goggles when checking optical path and adjusting optical axis.
- The filters are normally used at an incident angle of 0°, but may be used as pseudo beam splitters (beam division) at an incident angle of 45°. Note, however, that the ratio of non-transmitted light is not necessarily the ratio of reflection, as there is some light absorption in the filter.
- These filters are also called "neutral density filters", since they are optically neutral.
- ND filters (attenuators) for excimer lasers allowing adjustment of light intensity by the change in transmittance caused by the change in incident angle are also available.
| Material | MFND : BK7 MFNDU : Synthetic fused silica (SFS) |
|---|---|
| Coating | MFND : Cr Coating（Center wavelength 550nm） MFNDU : Cr Coating（Center wavelength 300nm） |
| Surface flatness | λ/ø30mm |
| Parallelism | MFND : ≤1 arcsec MFNDU : ≤30 arcmin |
| Wavelength Range | MFND:Visible( 400 —700nm ) MFNDU :UV (200 - 400nm) |
| Surface quality | 60-40 |
