The following is a compilation of a few definitions or examples of Light, Dark and Dim archives to better understand what they are.
The notion of "dark archives", supporting little or no access to archived materials, has met with scant enthusiasm in the library community. This suggests that digital repositories will function not just as guarantors of the long-term viability of materials in their custody, but also as access gateways. Lavoie
A secure digital repository sometimes referred to as a "dark archive" Kirsch
Light Archive: An archive that is accessible to the public. See also dim archive and dark archive. CDL