Patent ID: 11971321
Assignee: RAYTHEON COMPANY
Field: Measurement (Instruments)
Classification: CPC F  G  H | IPC F  G  H

Claim 0:
1. A method for monitoring a reflectance of a mirror target that includes at least one curved mirror, the method comprising:
obtaining a first irradiance measurement of the sun, the first irradiance measurement representing a direct solar irradiance;
obtaining a second irradiance measurement that represents an irradiance from a reflection of the sun from the mirror target plus background irradiance;
obtaining a third irradiance measurement that represents the background irradiance;
determining a reflectance of the mirror target from the first, second, and third irradiance measurements;
determining that the reflectance of the mirror target is less than a specified reflectance threshold; and
in response to the determination that the reflectance of the mirror target is less than the specified reflectance threshold, generating an alert signal.