Meanings of lenticular glass in English

The window was not of lenticular glass like those on shipboard, but was a simple flat pane.

The exterior plate immediately fell back upon its hinges like a port-hole, and the lenticular glass that covered the hole appeared.

Immediately the outer plate fell back upon its hinges like a porthole, and the lenticular glass which closed the scuttle appeared.

Other closely-fitting plates covered the lenticular glasses of the skylights.

Other plates, closely fitted, covered the lenticular glasses, and the travelers, hermetically enclosed in their metal prison, were plunged in profound darkness.