Help With Oriental Glass Triptych

Hello-
Can any of you help me identify what I have here? It's a folding glass triptych set in a hinged metal frame. The glass is cut and painted on the reverse. The subject is cranes. That middle section measures about 13-1/4" by 8-3/4" to give you a sense of its size. The metal (is it copper?) at least has a copper finish. Oriental (are they Japanese?) characters run down the left side of the center panel. Can anyone read them? It was coated with attic grime when acquired. I need help with what I have here-any thoughts will be appreciated.

 

Courtesy of Google Translate Japanese to English.