Patent ID: 6525330
Filing Date: 2003-02-25
Classification: G01N

Abstract:
A method for calibrating a strip sensor in an analytical meter device, the strip sensor having a photodectector and a light source, the method comprising the steps of:a. measuring the voltage output difference of said photodetector between when said light source is on and off using a standard having relatively high reflectance; b. measuring the voltage output difference of said photodetector between when said light source is on and off using a standard having relatively low reflectance; c. calculating a voltage threshold VTH produced by the strip sensor to be used by said analytical meter device to indicate when a test element has been inserted therein according to the formula: VTH=KTH[(VHighâˆ’VHighâ€”Off)âˆ’(VLowâˆ’VLowâ€”Off)]+(VLowâˆ’VLowâ€”Off) where KTH is a constant, VHigh is the voltage returned by a high-reflectance field with an LED on, VHighâ€”Off is the voltage returned after switching the LED off; and VLOW is the voltage returned by a low-reflectance field with an LED on, and VLOWâ€”Off is the voltage returned after switching the LED off;d. evaluating the value of VTH calculated in step (c) for acceptability according to predetermined criteria; e. permanently storing VTH in said analytical meter device if evaluated as acceptable in step (d).