Linear analog light-level monitoring system
First Claim
1. A system for remote monitoring of light levels, comprising:
- at least one sensor unit each remotely located from a central location, each sensor unit comprising;
(a) sensor means for sensing the level of light at a remote location and for providing a sensor signal linearly proportional to the sensed level of light;
(b) isolation means responsive to said sensor signal for isolating said sensor signal from electrical noise and for providing a noise-free output signal proportional to said sensor signal, said isolation means including feedback means for establishing the ratio of said output signal to said sensor signal; and
a control unit located at said central location comprising;
(a) at least one interconnect means, each for receiving a corresponding sensor unit output signal and for providing the received output signal from said control unit; and
(b) at least one calibration means each coupled to a corresponding sensor unit feedback means for modifying the ratio of the output signal to the sensor signal of the corresponding sensor unit.
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Accused Products
Abstract
A system for monitoring the level of light at a distant location from a central location. A light sensor at the location to be monitored is comprised essentially of a photodiode and an operational amplifier and produces a high-level, analog output signal on an output signal line, the signal being linearly proportional to the level of light at the location. A control unit at a central location is electrically coupled to the sensor and comprises a power supply for providing electrical power to the sensor and a calibration device connected to the output signal line for providing a feedback signal to the sensor. The calibration device may be adjusted so that the output signal at the control unit bears a selected ratio to the light detected. A control unit having a single and power supply may be coupled to a plurality of sensors.
29 Citations
13 Claims
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1. A system for remote monitoring of light levels, comprising:
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at least one sensor unit each remotely located from a central location, each sensor unit comprising; (a) sensor means for sensing the level of light at a remote location and for providing a sensor signal linearly proportional to the sensed level of light; (b) isolation means responsive to said sensor signal for isolating said sensor signal from electrical noise and for providing a noise-free output signal proportional to said sensor signal, said isolation means including feedback means for establishing the ratio of said output signal to said sensor signal; and a control unit located at said central location comprising; (a) at least one interconnect means, each for receiving a corresponding sensor unit output signal and for providing the received output signal from said control unit; and (b) at least one calibration means each coupled to a corresponding sensor unit feedback means for modifying the ratio of the output signal to the sensor signal of the corresponding sensor unit. - View Dependent Claims (2, 3, 4)
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5. A system for remote monitoring of light levels comprising:
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at least one sensor means each remotely located from a central location for sensing the level of light at a remote location and for providing an output signal linearly proportional to the sensed level of light; and a control unit located at a central location comprising; (a) at least one interconnect means each for receiving a corresponding sensor means output signal and for providing the received output signal from said control unit; (b) at least one calibration means each coupled to a corresponding sensor means for modifying the proportionality of the output signal to the level of light sensed by the corresponding sensor means; and (c) a power supply for providing power to each sensor means. - View Dependent Claims (6, 7, 8, 9)
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10. A system for remote monitoring of light levels, comprising;
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at least one sensor unit each remotely located from a central location, each sensor unit comprising; (a) sensor means for sensing the level of light at a remote location and for providing a sensor signal linearly proportional to the sensed level of light; (b) isolation means responsive to said sensor signal for isolating said sensor signal from electrical noise and for providing a noise-free output signal proportional to said sensor signal, said isolation means including feedback means for establishing the ratio of said output signal to said sensor signal; and a control unit located at said central location comprising; (a) at least one interconnect means, each for receiving a corresponding sensor unit output signal and for providing the received output signal from said control unit; (b) at least one calibration means each coupled to a corresponding sensor unit feedback means for modifying the ratio of the output signal to the sensor signal of the corresponding sensor unit; and (c) a power supply for providing power to each sensor unit. - View Dependent Claims (11, 12, 13)
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Specification