Electrooptical instrusion detection techniques and their application to remote viewing surveillance systems are studied. The technique used involves storing an image of a scene, comparing with it a later image of the scene to find a difference between the two images. An intruders arrival or motion in the scene will generate a difference signal. The interim report describes equipment developed to perform the differencing and preliminary results obtained with the equipment. The storage, comparison and generation of the difference signal are performed in the camera tube which is a Secondary Electron Conductivity Vidicon. The differencing operation consists of storing a positive charge image of the scene on a target electrode, then by changing appropriate biases storing a negative charge image of the later scene. The net charge is read out as the difference signal. Photographs of the video difference signal and of a monitor display of the difference signal are included. Measurements of detection sensitivity and susceptibility to false alarms are to be conducted in the course of the contract.