Methods and system for thermo-optic power monitoring

A radiation monitoring system for a lighting device, comprising:

• a first sensor and a second sensor positioned adjacent to a light-emitting element of a lighting device, wherein
• the first sensor receives radiation output directly from the light-emitting element and radiation output from external sources,
• the second sensor receives the radiation output from the external sources while shielded from the radiation output directly from the light-emitting element, wherein exposure of the first sensor and the second sensor to the radiation output from the external sources is equivalent, and
• electronic circuitry receiving output signals from the first sensor and the second sensor and calculating an intensity of the radiation output directly from the light-emitting element based on a difference in the output signals from the first sensor and the second sensor.