import tkinter as tk

root = tk.Tk()
root.title('PhotoImage')
root.geometry('250x220')

# カードの裏面の画像ファイルを読み込む
card_back_img = tk.PhotoImage(
  file='Cards\cardBack_blue1.png')  

canvas_1 = tk.Canvas(
  root, 
  width=240, 
  height=200)
canvas_1.pack()

canvas_1.create_image(120, 100,
  image=card_back_img,
  anchor='center')

root.mainloop()