BREATH ANALYZER SYSTEM AND METHOD OF OPERATING THE SAME
First Claim
1. A breath analyzer system for determining an estimate of blood alcohol concentration of a person, said system comprising:
- a light source configured to project light into a sampling region where breath from the person is expected;
a first light detector configured to detect a first light intensity of light emanating from the sampling region at an ethanol gas absorption wavelength, said first light detector further configured to output an ethanol gas signal indicative of an ethanol gas concentration in the sampling region;
a second light detector configured to detect a second light intensity of light emanating from the sampling region at a trace gas absorption wavelength, said second light detector further configured to output a trace gas signal indicative of a trace gas concentration in the sampling region; and
a controller configured to receive a first ethanol gas signal and a first trace gas signal sampled at substantially a first time, receive a second ethanol gas signal and a second trace gas signal sampled at substantially a second time distinct from the first time, and determine an estimate of the blood alcohol concentration of the person based on the first ethanol gas signal, the second ethanol gas signal, the first trace gas signal, and the second trace gas signal.
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Accused Products
Abstract
A breath analyzer system and method for determining an estimate of blood alcohol concentration of a person. A light source projects light into a sampling region where breath from the person is expected. A first light detector and a second light detector are configured to detect light intensity of light having certain wavelengths at a first time and a second time. Signals from the light detectors at the first time and the second time are used to determine an estimate of the blood alcohol concentration of the person by determining a ratio of a first light detector signal change to a second light detector signal change.
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Citations
24 Claims
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1. A breath analyzer system for determining an estimate of blood alcohol concentration of a person, said system comprising:
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a light source configured to project light into a sampling region where breath from the person is expected; a first light detector configured to detect a first light intensity of light emanating from the sampling region at an ethanol gas absorption wavelength, said first light detector further configured to output an ethanol gas signal indicative of an ethanol gas concentration in the sampling region; a second light detector configured to detect a second light intensity of light emanating from the sampling region at a trace gas absorption wavelength, said second light detector further configured to output a trace gas signal indicative of a trace gas concentration in the sampling region; and a controller configured to receive a first ethanol gas signal and a first trace gas signal sampled at substantially a first time, receive a second ethanol gas signal and a second trace gas signal sampled at substantially a second time distinct from the first time, and determine an estimate of the blood alcohol concentration of the person based on the first ethanol gas signal, the second ethanol gas signal, the first trace gas signal, and the second trace gas signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
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17. A breath analyzer system for determining an estimate of blood alcohol concentration of a person, said system comprising:
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a light source configured to project light into a sampling region where breath from the person is expected; a first light detector configured to detect a first light intensity of light emanating from the sampling region at an ethanol gas absorption wavelength, said first light detector further configured to output an ethanol gas signal indicative of an ethanol gas concentration in the sampling region; a second light detector configured to detect a second light intensity of light emanating from the sampling region at a carbon dioxide gas absorption wavelength, said second light detector further configured to output a carbon dioxide gas signal indicative of a carbon dioxide gas concentration in the sampling region; and a controller configured to select a first time and a second time distinct from the first time and both during a single exhale event by the person, receive a first ethanol gas signal and a first carbon dioxide gas signal sampled at substantially the first time, receive a second ethanol gas signal and a second carbon dioxide gas signal sampled at substantially the second time, determine an ethanol gas signal change based on a difference of the first ethanol gas signal and the second ethanol gas signal, determine a carbon dioxide gas signal change based on a difference of the first carbon dioxide gas signal and the second carbon dioxide gas signal, and determine an estimate of the blood alcohol concentration of the person based on a ratio of the ethanol gas signal change to the carbon dioxide gas signal change when the carbon dioxide gas signal change is greater than a threshold.
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18. A method for determining an estimate of blood alcohol concentration of a person, said method comprising the steps of:
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projecting light into a sampling region where breath from the person is expected; detecting a first light intensity of light emanating from the sampling region at an ethanol gas absorption wavelength and outputting an ethanol gas signal indicative of an ethanol gas concentration in the sampling region; detecting a second light intensity of light emanating from the sampling region at a trace gas absorption wavelength and outputting a trace gas signal indicative of a trace gas concentration in the sampling region; processing a first ethanol gas signal and a first trace gas signal sampled substantially at a first time; processing a second ethanol gas signal and a second trace gas signal sampled substantially at a second time distinct from the first time; and determining an estimate of the blood alcohol concentration of the gas based on the first ethanol gas signal, the second ethanol gas signal, the first trace gas signal, and the second trace gas signal. - View Dependent Claims (19, 20, 21, 22, 23, 24)
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Specification