DEVICE FOR MEASURING THE TRANSMITTANCE OF AN ELECTROCHROMATIC MEDIUM

摘要

A transmitivity sensor (10) having a light source and a detector (20) on one side (13) of a medium (11) with a reflector 14 on the other side (15) of the medium (11) so as to reflect the light (17) from the light source (16) back through the medium (11) to the detector (20). For instance, the sensor (10) may be used on a window (11) of a sealed building or container without having connections to the source (16) and detector (20) break the integrity of the window seal relative to the building or the container. The magnitude of the light signal (17) on the detector (20) relative to that of the source is an indication of the transmitivity of the window (11). Electronics (12) to effectively implement the sensor (10) are connected to the source (16) and detector (20). The electronics (12) may contain, for example, a source driver, a detector amplifier, a band-pass filter, a logarithmic amplifier and various voltage sources. Other items may be a part of the electronics as desired.