Nondispersive infrared gas analyzer
First Claim
1. A nondispersive infrared gas analyzer of the type having a plurality of gas-filled chambers arranged in the propagation path of modulated infrared radiation, and a measuring pickup for producing an electrical measurement signal, the nondispersive infrared gas analyzer further comprising:
- pulsed energy supply means for producing electrical pulses having a duty cycle which is less than 1;
infrared radiation means for producing infrared radiation which is modulated in response to said duty cycle of said pulsed energy supply means, said infrared radiation means having a predetermined continuous power rating; and
pulse control means for terminating each of said electrical pulses from said pulsed energy supply means in response to a peak value of a corresponding pulse in the electrical measurement signal.
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Accused Products
Abstract
A nondispersive infrared gas analyzer of the type wherein gas-filled chambers are arranged in the path of modulated infrared radiation. A measurement pickup is provided for producing a signal responsive to the response of a gas contained in the chamber to the infrared radiation. The infrared radiation is produced by a source of infrared radiation which is powered by a pulsed energy supply, the pulsed energy supply being responsive to control signals so as to provide pulses which have a duty cycle which is less than 1, and preferably between 0.1 and 0.5. The duration of the pulses is controlled in response to the maximum value of a measuring signal of an output of a measuring pickup. In other embodiments, the duration of the pulses may be determined empirically, by calculation, or by means of peak detector. This arrangement provides almost 100% modulation while considerably reducing power consumption and without loss of sensitivity. As such, the invention is particularly useful in battery-operated nondispersive infrared gas analyzer equipment adapted for field use.
23 Citations
5 Claims
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1. A nondispersive infrared gas analyzer of the type having a plurality of gas-filled chambers arranged in the propagation path of modulated infrared radiation, and a measuring pickup for producing an electrical measurement signal, the nondispersive infrared gas analyzer further comprising:
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pulsed energy supply means for producing electrical pulses having a duty cycle which is less than 1; infrared radiation means for producing infrared radiation which is modulated in response to said duty cycle of said pulsed energy supply means, said infrared radiation means having a predetermined continuous power rating; and pulse control means for terminating each of said electrical pulses from said pulsed energy supply means in response to a peak value of a corresponding pulse in the electrical measurement signal. - View Dependent Claims (2, 3, 4, 5)
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Specification