System for camera flash units - has flash unit emitting controlled pulses with slave flash unit activated when flash from first unit is detected

摘要

An arrangement of two separate flash units for a camera has each unit emitting its light in a series of single pulses. The pulses from one unit are controllable whereas the second unit has a receiver which detects the emission of a pulse from the other unit, and only then gives out its own pulse. The controller for the first unit measures the light reflected from the object being photographed and if a certain light threshold is reached, it sends a switch-off signal to the pulse circuit. The controller may be in the flash unit or in the camera itself. The controlled flash unit may be mounted on the camera or integral with it. ADVANTAGE- Inexpensive auto-flash system.