REGULATING SYSTEMS

摘要

A system for regulating the value of a radiation dependent parameter has an electrically controlled variably transmissive element (56), a sensor (52) and an adaptation unit (54) responsive to the signal from the sensor to provide a voltage to vary the transmissivity of the element over a substantially continuous range, so as to regulate the radiation dependent parameter. The element may be of liquid crystal type or electrochromic. The adaptation unit may correct for non-linear properties of the system or the system may function in a feedback mode. Additional sensors may be used to prompt switching of the adaptation unit between different modes. The system may regulate several parameters. A multiple layer element structure (171) is also disclosed.