METHOD AND APPARATUS FOR ANALYZING SOLUTIONS
First Claim
1. A self-calibrating device for analyzing an aqueous solution, the device comprising:
- a test element comprising a reagent responsive in color to a characteristic of an aqueous solution wetting the test element;
a radiation source producing radiation across a spectrum of wavelengths for illuminating the test element when the wetted test element is placed in a test element receiving port of the device, a portion of the radiation being reflected from the test element in response to the color of the test strip;
circuitry for detecting an intensity of the reflected radiation in each of a plurality of wavelength ranges; and
a processor implementing coded instructions for calculating a ratio among the intensities of the detected reflected radiation in the plurality of wavelength ranges, and for correlating the calculated ratio to the characteristic of the solution.
1 Assignment
0 Petitions
Accused Products
Abstract
An apparatus and method of analyzing an aqueous solution, as may be implemented with a hand-held portable electronic device (10). A test pad (32) responsive in color to a characteristic of an aqueous solution is interrogated by the device by measuring, in a plurality of wavelength ranges, intensity values of a test light as reflected off of the test strip. The intensity values may be expressed as values relative to intensities reflected off of white and black calibration surfaces. A relationship among the intensity values for the various wavelength ranges is developed through an algorithm that provides a ratio value that is responsive to the characteristic of the aqueous solution and that is non-responsive to absolute intensity values of the reflected light. The test pad may be supported on an opaque and non-reflective substrate (28) that cooperates with an opaque edge portion (14E) of a test element placement member (14B) and associated side walls (14W) of the device to minimize the impingement of ambient light onto the test pad during interrogation.
-
Citations
22 Claims
-
1. A self-calibrating device for analyzing an aqueous solution, the device comprising:
-
a test element comprising a reagent responsive in color to a characteristic of an aqueous solution wetting the test element;
a radiation source producing radiation across a spectrum of wavelengths for illuminating the test element when the wetted test element is placed in a test element receiving port of the device, a portion of the radiation being reflected from the test element in response to the color of the test strip;
circuitry for detecting an intensity of the reflected radiation in each of a plurality of wavelength ranges; and
a processor implementing coded instructions for calculating a ratio among the intensities of the detected reflected radiation in the plurality of wavelength ranges, and for correlating the calculated ratio to the characteristic of the solution. - View Dependent Claims (2)
-
-
3. A method of analyzing an aqueous solution, the method comprising:
-
wetting a test strip with an aqueous solution, the test strip comprising a reagent responsive in color to a characteristic of the solution;
exposing the test strip to interrogating radiation comprising a spectrum of wavelengths, a portion of the radiation being reflected from the test strip in response to the color of the test strip;
detecting an intensity of the reflected radiation in each of a plurality of wavelength ranges;
calculating a ratio among the intensities of the detected reflected radiation in the plurality of wavelength ranges; and
correlating the calculated ratio to the characteristic of the solution. - View Dependent Claims (4, 5, 6, 7)
-
-
8. A method implemented with an electronic device used to analyze an aqueous solution, the electronic device comprising a radiation source for illuminating a test strip wetted with the aqueous solution, a reflected radiation detector producing a signal responsive to radiation reflected from the test strip, the signal responsive to a color of the test strip which is responsive to a characteristic of the aqueous solution, circuitry associated with the radiation detector for analyzing the signal and for producing an output responsive to the characteristic of the aqueous solution, the method comprising:
-
detecting, in a plurality of wavelength ranges, radiation reflected from a test strip wetted with an aqueous solution;
expressing an intensity of the detected reflected radiation in each of the plurality of wavelength ranges as a value relative to calibration values of intensity of radiation reflected from a dark surface and intensity of radiation reflected from a white surface for the respective wavelength range;
processing the relative intensity values through an algorithm to calculate a ratio among the relative intensity values responsive to a characteristic of the aqueous solution; and
correlating the calculated ratio to a characteristic of the aqueous solution. - View Dependent Claims (9, 10, 11, 12)
-
-
13. A test element for use with an associated electronic tester for determining a characteristic of an aqueous solution, the tester including a test element receiving port at least partially defined by opposed walls upwardly extending from a test element placement member at least a portion of which is transparent to radiation, a source of radiation for illuminating the test element when positioned on the test element placement member, and sensors to detect radiation reflected from the illuminated test element, the test element comprising:
-
an opaque substrate;
a first side of the substrate comprising a non-reflective surface; and
a test pad attached to the first side of the substrate and comprising a reagent responsive in color to a characteristic of an aqueous solution;
wherein the opaque substrate and the non-reflective surface are operative to control ambient light and reflections during interrogation of the test pad by the tester when the test element is placed into the test element receiving port with the test pad disposed against the test element placement member. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22)
-
Specification