04131540 is referenced by 28 patents and cites 2 patents.

A tomato sorter is described for removing culls, e.g. green tomatoes from the good, red tomatoes. An image of each tomato passing the station is formed on a light diffusing plate. Diffused light from the plate is divided into first and second light beams from which all but the red and the green light components, respectively, are removed with filters. The remaining light is sensed by separate photo-multipliers, the output of which is used to form red and green light intensity signals. When the differential between the red and green signals exceeds a predetermined value, a reject signal is generated which actuates a mechanism for removing the affected tomato from the tomato flow.

Title
Color sorting system
Application Number
5/793679
Publication Number
4131540
Application Date
May 4, 1977
Publication Date
December 26, 1978
Inventor
Ron E Swanson
Sunnyvale
CA, US
Ron J Fleming
San Jose
CA, US
Robert G Husome
Jerome
ID, US
Agent
Townsend and Townsend
Assignee
Acurex Corporation
CA, US
Johnson Farm Machinery Co
CA, US
IPC
B07C 5/344
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