Honeycomb are the blinds sandwiched between the glass. These blinds are created by using honeycomb material instead of slates. Honeycomb material is internally aluminium coated, which provides protection against the ultra violet rays.
Installation of Honeycomb can suits you the best if you want to avoid the pinhole lights of the slats.
Honeycomb is extremely useful to create complete darkness in the area, as it does not allow light to pass through.