No English Term
An opaque screen located at the optic and intended to reduce the luminous intensity of the beam, and also, in the case of revolving optics, to reduce the angle of uncertainty
Note: In the second case, this is a form of "cut screen".
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
Number of cells
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM