Possible Clues:

• Flat surface onto which images are projected
• Partition - the cinema
• What a riddle that there should be pictures there!
• Guard seen protecting crown
• Vet show on television
• It's a riddle how this could be viewed about the crescendo
• Bruce: "The ___ door slams, Mary's dress waves"
• Window attachment
• Projected on this, it may be seen about the crescendo
• Put on to hide