Unusual Postcard - Is there a term for this type of card?

This is labeled "Street Scene, Hudson, Mass." and is postmarked 1906.

It's a little hard to photograph, but the card has an irridescent overprinting on the windows (only) of the buildings that makes them appear illuminated when held at the proper angle (like a Thomas Kinkade print), and then plain when rotated. The effect shows best in the building to the far right, but is employed on all the buildings shown.

Haven't been able to find a similar. Anyone know if there is a specific term in the PC collecting fraternity that describes such a printing method?