A new-style nonlinear light sensor of adjustable threshold has been fabricated by packaging a silicon photoelectronic negative resistance device and an LED together,and using the photo-bistable and self-locking characteristics of the negative resistance device.It is shown this light sensor can realize the photoelectronic coupling of signals,and a series of signal processing functions such as threshold setting,comparing,and output driving.It also has a simple structure and can be modulated conveniently.