公开(公告)号：USD608300S1

公开(公告)日：2010-01-19

申请号：US29331637

申请日：2009-01-29

Applicant: John Boyland ,  Shelly Hylton ,  Nurit Barlev Rohar ,  George Yundt ,  Mike Joseph ,  Perry Slaughter ,  Talmage Mathis ,  George Ellis ,  Wei Tong ,  Lyle Ostby ,  Jerry Johnson ,  Oren Saraf

Designer： John Boyland ,  Shelly Hylton ,  Nurit Barlev Rohar ,  George Yundt ,  Mike Joseph ,  Perry Slaughter ,  Talmage Mathis ,  George Ellis ,  Wei Tong ,  Lyle Ostby ,  Jerry Johnson ,  Oren Saraf

公开(公告)号：US4762992A

公开(公告)日：1988-08-09

申请号：US60213

申请日：1987-06-10

Applicant: Erann Gat ,  Eric D. Park ,  Talmage Mathis

Inventor： Erann Gat ,  Eric D. Park ,  Talmage Mathis

IPC: G01D5/26 ,  G01D5/353 ,  G01F23/00 ,  G01F23/292 ,  G01M11/00 ,  G01V8/16 ,  G08C25/00 ,  H04L25/06 ,  H01J5/16

CPC classification number: G01F23/0069 ,  G01D5/268 ,  G01F23/2925 ,  H04L25/06

Abstract: An error detection system is provided for a two-state fiber optic sensor. An amplified photodetector signal is sampled by each of an ON-OFF threshold detector, a disconnect threshold detector and a slope detector. The ON-OFF threshold detector monitors whether the detector signal is above or below an ON-OFF threshold value corresponding to the parameter being sensed and activates an appropriate sensor output. The disconnect threshold detector monitors the constant low level detector signal corresponding to low level light received by the detector even when the thresold detector is in the OFF state, and triggers an error signal should the detector signal fall below a disconnect threshold value. The slope detector monitors the rate of change of the detector signal. Where the detector signal changes rapidly, such as during normal sensor switching, the slope detector permits the detector signal to pass to a latch, which retains in memory the last detector signal which changed rapidly enough to trigger the slope detector and produces an output corresponding to the ON-OFF status of the last detector signal in memory. A slowly changing detector will not trigger the slope detector. Where the outputs of the ON-OFF threshold detector and the latch differ, a comparator triggers an error signal.