Diplopia - the perception of 2 images of a single object. Diplopia may be monocular or binocular. Monocular diplopia is present when only one eye is open. Binocular diplopia disappears when either eye is closed.
Juliette Balcony - Providing a 'guard' or security barrier to sliding doors or inward opening full-height French Doors on a first-floor room or above, a Juliet balcony lets in more natural light, and fresh air when the doors are open
Momochan:
