Intruder-detection system for room security

Claim 2

A security system comprising one infrared-transmitting element and at least two detector elements producing individual electrical output signals in response to infrared radiation within the wavelength region of said transmitting element, means mounting said transmitting element for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said mounting means also mounting said detector elements in spaced relation laterally of said transmitting element and such that the response of each of said detector elements fully laps said space field; electronic means including means sampling and storing the output signals of said detector elements in alternation, evaluating means connected to evaluate currently sampled values against stored values in keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both a keying interval for one detector element and the successive keying interval for the other detector element.

Claim 3

A security system comprising at least two like infrared transmitting elements and one infrared detector element producing an electrical output signal in response to infrared radiation within the wavelength region of said transmitting elements, means mounting said detector element for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said mounting means also mounting said transmitting elements in spaced relation laterally of said detector element and such that the irradiation response of each of said transmitting elements fully laps said space field; electronic means including means keying the excitation of said transmitting elements in alternation, evaluating means connected to sample and store detected values for first keying intervals for one transmitting element in alternation with separate sampling and storage of detected values for second keying intervals of the other transmitting element, said evaluating means being connected to separately evaluate currently sampled values against stored values for said first and second keying intervals, and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for detected vs. stored signals in both of said keying intervals.

Claim 4

A security system comprising at least two like infrared transmitting elements and one infrared detector element producing an electrical output signal in response to infrared radiation within the wavelength region of said transmitting elements, means mounting said detector element for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said mounting means also mounting said transmitting elements in spaced relation laterally of said detector element and such that the irradiation response of each of said transmitting elements fully laps said space field; electronic means including means keying the excitation of said transmitting elements in alternation, evaluating means connected to sample and store detected values for first keying intervals for one transmitting element in alternation with separate sampling and storage of detected values for second keying intervals of the other transmitting element, said evaluating means being connected to separately evaluate currently sampled values against stored values for said first and second keying intervals, and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for detected vs. stored signals in both of said keying intervals.

Claim 5

A security system comprising first and second transmitting subsystems wherein each subsystem comprises an infrared-transmitting element mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said subsystems being mounted in laterally spaced proximity with equal numbers of intruder-response sectors and with corresponding sectors of the respective subsystem oriented in laterally offset proximity and for response to said space field; at least two detector elements producing individual electrical output signals in response to infrared radiation within the wavelength region of said transmitting subsystems and mounted in spaced adjacency to each other and to said transmitting subsystems such that the response field of each of said detector elements fully laps said space field; electronic means including means sampling and storing the outputs of said detector elements in alternation, evaluating means connected to evaluate currently sampled values against stored values and in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 6

A security system comprising first and second transmitting subsystems wherein each subsystem comprises an infrared-transmitting element mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said subsystems being mounted in laterally spaced proximity with equal numbers of intruder-response sectors and with corresponding sectors of the respective subsystem oriented in laterally offset proximity and for response to said space field; at least two detector elements producing individual electrical output signals in response to infrared radiation within the wavelength region of said transmitting subsystems and mounted in spaced adjacency to each other and to said transmitting subsystems such that the response field of each of said detector elements fully laps said space field; electronic means including means sampling and storing the outputs of said detector elements in alternation, evaluating means connected to evaluate currently sampled values against stored values and in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 7

A security system comprising first and second detecting subsystems wherein each subsystem comprises at least one infrared-responsive detector element mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said subsystems being mounted in laterally spaced proximity with equal numbers of intruder-response sectors and with corresponding sectors of the respective subsystems oriented in laterally offset proximity and for response to said space field; at least two laterally spaced transmitting elements for transmitting infrared radiation within the response wavelength region of said detector elements, said transmitting elements being mounted in spaced adjacency to said detecting subsystems and such that each of said transmitting elements can irradiate said space field; electronic means including key means keying said transmitting elements for alternating transmission, means for sampling and storing the separate output of said detector elements in keyed synchronism with the keying of said transmitting elements, evaluating means connected to evaluate currently sampled values against stored values in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 8

A security system comprising first and second detecting subsystems wherein each subsystem comprises at least one infrared-responsive detector element mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said subsystems being mounted in laterally spaced proximity with equal numbers of intruder-response sectors and with corresponding sectors of the respective subsystems oriented in laterally offset proximity and for response to said space field; at least two laterally spaced transmitting elements for transmitting infrared radiation within the response wavelength region of said detector elements, said transmitting elements being mounted in spaced adjacency to said detecting subsystems and such that each of said transmitting elements can irradiate said space field; electronic means including key means keying said transmitting elements for alternating transmission, means for sampling and storing the separate output of said detector elements in keyed synchronism with the keying of said transmitting elements, evaluating means connected to evaluate currently sampled values against stored values in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 9

A security system comprising first and second transmitting subsystems wherein each subsystem comprises at least one infrared-transmitting element and wherein the subsystem is mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said intruder-response sectors being spaced by at least substantially three times the angular width of a single intruder-response sector, and the mounting of said subsystems being such that the intruder-response sectors of one subsystem are in substantially uniformly spaced interlace with the intruder-response sectors of the other system in their mutual coverage of said field; at least two detector elements producing individual electrical output signals in response to infrared radiation within the wavelength region of said transmitting subsystems and mounted in spaced adjacency to each other and to said transmitting subsystems such that the response field of each of said detector elements fully laps said space field; electronic means including key means alternately keying said transmitting elements for alternating transmission, means for sampling and storing the separate outputs of said detector elements in keyed synchronism with the keying of said transmitting elements, evaluating means connected to evaluate currently sampled values against stored values in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 10

A security system comprising first and second transmitting subsystems wherein each subsystem comprises at least one infrared-transmitting element and wherein the subsystem is mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors which span a space field to be protected, said intruder-response sectors being spaced by at least substantially three times the angular width of a single intruder-response sector, and the mounting of said subsystems being such that the intruder-response sectors of one subsystem are in substantially uniformly spaced interlace with the intruder-response sectors of the other system in their mutual coverage of said field; at least two detector elements producing individual electrical output signals in response to infrared radiation within the wavelength region of said transmitting subsystems and mounted in spaced adjacency to each other and to said transmitting subsystems such that the response field of each of said detector elements fully laps said space field; electronic means including key means alternately keying said transmitting elements for alternating transmission, means for sampling and storing the separate outputs of said detector elements in keyed synchronism with the keying of said transmitting elements, evaluating means connected to evaluate currently sampled values against stored values in alternation synchronized with said keyed alternation; and threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.

Claim 11

The system of claim 5, in which each of said subsystems comprises a plurality of transmitting elements, there being one transmitting element determining each intruder-response sector.

Claim 12

A security system comprising first and second detecting subsystems wherein each subsystem comprises at least one detector element and wherein the subsystem is mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors spaced by at least substantially three times the angular width of a single intruder-response sector, and the mounting of said subsystems being such that the intruder-response sectors of one subsystem are in substantially uniformly spaced interlace with the intruder-response sectors of the other system in their mutual coverage of said field; at least two laterally spaced transmitting elements for transmitting infrared radiation within the response wavelength region of said detector elements, said transmitting elements being in spaced adjacency to said detecting subsystems and such that each of said transmitting elements can irradiate said space field; electronic means including key means keying said transmitting elements for alternating transmission, means for sampling and storing the separate outputs of said detector elements in keyed synchronism with the keying of said transmitting elements.

Claim 13

A security system comprising first and second detecting subsystems wherein each subsystem comprises at least one detector element and wherein the subsystem is mounted for directionally limited response in a plurality of angularly spaced intruder-response sectors spaced by at least substantially three times the angular width of a single intruder-response sector, and the mounting of said subsystems being such that the intruder-response sectors of one subsystem are in substantially uniformly spaced interlace with the intruder-response sectors of the other system in their mutual coverage of said field; at least two laterally spaced transmitting elements for transmitting infrared radiation within the response wavelength region of said detector elements, said transmitting elements being in spaced adjacency to said detecting subsystems and such that each of said transmitting elements can irradiate said space field; electronic means including key means keying said transmitting elements for alternating transmission, means for sampling and storing the separate outputs of said detector elements in keyed synchronism with the keying of said transmitting elements.

Claim 14

The system of claim 7, in which each of said subsystems comprises a plurality of detector elements, there being one detector element determining each intruder-response sector.

Claim 15

The system of claim 7, and including threshold-operated alarm means connected to produce an alarm-signal output only upon concurrent evaluation of at least a predetermined difference in value for currently detected vs. stored signals in both of said keying intervals.