If you squint you can see the distinctive bars in the letters E, A and, H. A line made of tiny triangles. Wikipedia:
Longchamps was a chain of several upscale restaurants centered in Manhattan that consisted of twenty or more locations at its peak, including the Showboat Restaurant located in the Empire State Building. The chain's first location was opened in 1919.
Longchamps restaurants were known for their natty art deco furnishings and decorations by Winold Reiss,and a number of designs for elements of their physical surroundings were drawn up by New York architect Ely Jacques Kahn, originator of a colorful version of art deco architecture.
Belly-up in the mid 70s.