Obtaining information from optical cavity output light

A method of using optical cavities;

• the method comprising:
• photosensing output light from an optical cavity that can provide light in a set of one or more modes;
• for one or more of the modes in the set, the output light including a respective intensity function;
• the intensity function of at least one of the modes including information about an optical characteristic of an analyte present in the optical cavity or of a region of the optical cavity;
• the act of photosensing output light comprising:
• providing electrical signals that depend on the optical characteristic;
• and
• using the electrical signals to obtain information about the analyte or the region.

A system comprising:

• a photosensing component that can photosense output light from a sample optical cavity that provides output light in a set of one or more modes, each having a respective intensity function;
• a sample being present in the optical cavity;
• in response to the output light, the photosensing component providing electrical signals that depend on whether an analyte is present in the sample;
• if the analyte is present, an optical characteristic of the analyte affecting the respective intensity function of at least one of the modes in the set, the electrical signals indicating a feature of the intensity function;
• and
• an information obtaining component that uses the electrical signals to obtain information about presence of the analyte in the sample.

A method of using optical cavities;

• the method comprising:
• photosensing output light from an optical cavity that can provide output light in a set of one or more modes, each having a respective intensity function;
• a sample being present in the optical cavity;
• the act of photosensing output light comprising:
• providing electrical signals that depend on whether an analyte is present in the sample;
• if the analyte is present, an optical characteristic of the analyte affecting the respective intensity function of at least one of the modes in the set, the electrical signals indicating a feature of the intensity function;
• and
• using the electrical signals to obtain information about presence of the analyte in the sample.