SPECIAL CONSIDERATIONS
•Keep the plastic domed cosine corrector clean and free of scratches. It may be cleaned with a soft cloth and isopropyl alcohol.
•When light is received from many directions simultaneously, take special care to avoid reflections or shadowing the sensor with your body.
•For best accuracy, repeat the measurement several times to ensure that the light source has remained stable.
•Avoid flexing the cable excessively at either end of the cable.
•The Inverse-square Law
The law stating that the illuminance E at a point on a surface varies directly with the intensity I of a point source, and inversely as the square of the distance d between the source and the point. If the surface at the point is normal to the direction of the incident light, the law is expressed by E=I/d2.
•Cosine Law
The law that the illuminance on any surface varies as the cosine of the angle of incidence. The angle of incidence q is the angle between the normal to the surface and the direction of the incident light. The
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