Opto-electronic position sensing

Claim 2

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements of said detectors vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, and second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements identified by said first means.

Claim 3

A system as claimed in claim 1 wherein said second means includes calculating means for calculating a ratio of the sum and difference of said output signals from said affected elements identified by said first means so as to indicate the position of said member in said system.

Claim 4

A system as claimed in claim 2 wherein said first means identifies three affected elements from said detectors by said digital analysis and said second means subtracts one of said three signals having the smallest magnitude output from said three output signals to obtain two non-zero values for determining said position of said member.

Claim 5

A system as claimed in claim 1 wherein movement of said member is relatively slow and said system further comprises energizing means for relatively rapidly energizing said sources sequentially and determining means for relatively rapidly examining said detectors sequentially for affected elements.

Claim 6

A system as claimed in claim 1 wherein each of said radiation sources irradiates only a respective detecting element of said radiation detectors.

Claim 7

A system as claimed in claim 1, wherein said member variably, according to its position, reflects radiation from said sources towards said detectors.

Claim 8

A system as claimed in claim 1 further comprising diffusing means for diffusing said radiation from each source.

Claim 9

A system as claimed in claim 1 wherein said member is a fluid flow sensor member in a tube.

Claim 10

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, and second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements and by comparing an output magnitude from each of said affected elements with the magnitude of the respective output when the element is unaffected by said member.

Claim 11

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, and second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements and by comparing an output magnitude from each of said affected elements with the magnitude of the respective output when the element is unaffected by said member.

Claim 12

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements identified by said first means, storage means for storing a reference output for each element, said reference output being an output of that element when unaffected by said member, and subtraction means for subtracting said reference outputs from respective output signals of said detectors.

Claim 13

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements identified by said first means, storage means for storing a reference output for each element, said reference output being an output of that element when unaffected by said member, and subtraction means for subtracting said reference outputs from respective output signals of said detectors.

Claim 14

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, said series of detectors being offset with respect to said series of sources whereby each detector is irradiated by two radiation sources, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements of said detectors vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, and second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements identified by said first means.

Claim 15

An opto-electronic position-sensing system comprising: a series of emitting sources for generating radiation, a series of radiation detectors for receiving said radiation, said series of detectors being offset with respect to said series of sources whereby each detector is irradiated by two radiation sources, a movable member located between said emitting sources and said detectors for affecting radiation reception of various affected elements of said detectors by blocking radiation from said sources to said elements according to a longitudinal position of said member relative to said sources, each affected element being adapted to produce an analog output signal having a magnitude varying from a minimum to a maximum and responsive to said position of said member in such a manner that output signals of at least two of said elements of said detectors vary in accordance with movement of said member, first means for identifying said affected elements having low outputs by digital analysis of said output signals from said detectors so as to indicate the position of said member in said system, and second means for subsequently precisely determining said position of said member by analog analysis of said output signals from said affected elements identified by said first means.

Claim 18

A method as claimed in claim 12 wherein said analog analysis includes calculating the ratio of the sum and difference of said outputs from said affected elements being identified by digital analysis.

Claim 19

A method as claimed in claim 13 wherein said digital analysis of said outputs from said detectors includes identifying three elements affected by said member and wherein said analog analysis includes subtracting the smallest magnitude output of said three outputs from all three outputs of the said detectors.

Claim 20

A method as claimed in claim 12 further including relatively rapidly energizing the sources sequentially and relatively rapidly examining said detectors sequentially for affected elements.

Claim 21

A method as claimed in claim 12 further including arranging said emitting sources and said radiation detectors such that each emitting source irradiates only a respective detecting element of said radiation detectors.

Claim 22

A method as claimed in claim 12 including arranging the radiation sources, the radiation detectors and the member such that the member variably, according to its position, reflects radiation from said sources towards said detectors.

Claim 23

A method as claimed in claim 12 including diffusing said radiation from each source.