초록 ▼

An apparatus for enhancing the analysis of light reflected from a blood exposed reagent is described. Light from sources, such as LED's, is used to detect the levels of glucose and fructosamine in the blood exposed reagent. A special optical arrangement is used to obtain optical signals indicative o

An apparatus for enhancing the analysis of light reflected from a blood exposed reagent is described. Light from sources, such as LED's, is used to detect the levels of glucose and fructosamine in the blood exposed reagent. A special optical arrangement is used to obtain optical signals indicative of the optically sensitive chemicals in the reagent. The optical beams from respective LED's are directed at a common surface of an optical element used to redirect the light onto the reagent and reflect portions onto a reference detector. A main detector is strategically located adjacent a surface of the optical element to detect reflections from the reagent. A control circuit is described with which the light from the LED light sources can be held at substantially constant levels despite factors tending to cause light level changes.

대표청구항 ▼

[What is claimed is:] [1.]a housing having a surface for receiving reagent strips and having an optical aperture through which an optical beam from inside the housing can illuminate the reagent on the strip;an optical beam generating structure positioned inside the housing and producing said optical

[What is claimed is:] [1.]a housing having a surface for receiving reagent strips and having an optical aperture through which an optical beam from inside the housing can illuminate the reagent on the strip;an optical beam generating structure positioned inside the housing and producing said optical beam through said optical aperture with light from a reagent strip being reflected back through said aperture for detection; said optical beam generating structure further including:a first light source producing an optical beam directed toward said reagent strip,a reference photo detector located to detect a portion of the optical beam;a main photo detector located to detect reflections caused by the incidence of the optical beam onto said reagent strip;a control circuit coupled to said light source and said reference detector to maintain the light output from said light source substantially constant; andwherein said reference detector and said main detectors are so selected that a sensitivity versus wavelength characteristic of said main detector is different from a sensitivity versus wavelength characteristic of said reference detector, said reference detector being selected so that its sensitivity as a function of wavelength is sufficient to super-impose on the control circuit a compensation for changes in the wavelength of the light source and attributable to changes in the light source's drive current or operating temperature.