Optoelectronic lawn tennis linesman system

Claim 1

An optoelectronic lawn tennis linesman system, comprising: (i) twenty optical line watchers including eight below net line watchers and twelve out-of-court line watchers, for arrangement on a tennis court in an array comprising two below net line watcher at each central serving line, and two opposing line watchers for watching each of remaining lines, including a below net line watcher and an out-of-court line watcher monitoring each sideline, and opposing out-of-court line watchers monitoring each service line and baseline; and (ii) electronic means cooperative with said optical line watchers for audio announcement and/or visual display of line call events in response to detection by said optical line watchers of the color of a tennis ball in line areas monitored by said line watchers; wherein said below net line watchers comprise: (a) a diaphragm, limiting the watched area along the line monitored by the below net line watcher; (b) a battery of filters which selectively attenuates optical signals received from sources other than said tennis ball and which allows a color image attributable to said tennis ball to pass therethrough; (c) a concentrating concave mirror, which concentrates the image passed through said battery of filters; (d) a lens system for focusing the image concentrated by said concentrating concave mirror; (e) a right prism which receives the image focused by said lens system and downwardly redirects the focused image; (f) a terrestrial periscope lens system for passing the downwardly redirected focused image from the first right prism therethrough; (g) a second right prism which receives the image passed through said terresterial periscope lens system and redirects it in a horizontal direction; (h) a first optical connector, matched to said second right prism; (i) a glass fiber optical conductor, matched to said first optical connector; and (j) a second optical connector matched to said glass fiber optical conductor.