SIMPLE LIGHT (LUX) METER
Categories : Series 9 Generally Electronic Project ,  Measurement & Tester , 
This circuit uses a photo-transistor as the light measurement element. A transistor amplifier drives an array of 5 LEDs in proportion to the light intensity received. If measurement relative to background conditions is required, an on-board trimmer potentiometer is available to compensate for ambience.
Technical Specification