Fouling layer detection on an environmental sensor

摘要

An environmental sensor is disclosed. The environmental sensor includes a semiconductor substrate including a light sensor, a surface through which ambient light can pass to reach a light sensor and a light source operable to illuminate the surface, whereby at least some of the light from the light source is reflected by the surface onto the light sensor. The environmental sensor is operable to determine the presence of a fouling layer on the surface by comparing measurements of ambient light and reflected light by the at least one light sensor.

主权项

1. An environmental sensor comprising:
a semiconductor substrate including a light sensor; a surface through which ambient light can pass to reach the light sensor, and a light source configured to illuminate the surface, whereby at least some light from the light source is reflected by the surface onto the light sensor, wherein the environmental sensor is configured to determine a presence of a fouling layer on the surface by comparing measurements of the ambient light and the reflected light by the light sensor to the reflected light of an unused environmental sensor that has not been exposed to an environment.