Patent ID: 7354772

Claim:
An optical system for determining information about an assay, comprising: a laser comprising a laser resonating cavity, the laser resonating cavity comprising a gain medium, the laser resonating cavity configured to incorporate at least a portion of a filter assembly having a first and second surface, an assay disposed on the first surface, such that the first surface and the assay are disposed exterior to the laser resonating cavity and the second surface is disposed within the laser resonating cavity, wherein the laser resonating cavity is configured such that a reaction of the assay changes optical reflectance of the filter assembly and results in a change to a resonant characteristic of the laser resonating cavity that affects at least one characteristic of light propagating in the laser resonating cavity; means for providing light to the laser resonating cavity; and means for determining information about a reaction in the assay by analyzing one or more characteristics of light propagating in the laser resonating cavity.