Patent ID: 7666262

Claim:
A method of cleaning a front side of a large format movie screen, comprising the steps of a) positioning a cleaning head against the front side of the screen so that a least a portion of the cleaning head is vertically aligned with a selected portion of the front side of the screen to be cleaned, b) moving the cleaning head vertically up and down against the selected portion with a winch system to clean the selected portion, c) repositioning the cleaning head against the screen so that at least a portion of the cleaning head is vertically aligned with an additional portion of the screen to be cleaned, d) moving the cleaning head up and down against the additional portion of the screen to clean the additional portion of the screen, e) repeating steps c) and d) until the entire screen has been cleaned, wherein the additional portion overlaps with the selected portion, and steps c) and d) are carried out to clean overlapping portions of the screen, a single pulley is provided above an upper end of the screen, said pulley being spaced a first distance in front of the front side of the screen, a single cable mounting point is provided on the cleaning head, said cable mounting point being a second distance in front of the front side of the screen, a cable connects the single pulley with the single cable mounting point, and said first distance and said second distance are selected so that gravity urges the cleaning head against the screen adequately to effect cleaning.