Abstract: Many continuous processes, such as paper manufacturing, use analog camera systems to capture break events and use the video information to diagnose runnability problems. These systems trigger off a break signal on the machine and synchronize all videos to the same point on the process using the machine speed. The present invention provides a new approach to use real-time information from digital cameras to perform image analysis in real time and execute specific control functions normally performed by operators. A reference image is defined as the control objective function and each frame from the cameras is compared to the reference image. Deviations from the reference image that exceed a defined deadband (the threshold) are output to the control system to take corrective action. The applications of the disclosed approach include dynamic draw control, trim control, tension control, release angle control, creping blade control with control signals determined from a two-dimensional camera image.

Abstract: A visual stimulator for light stimulation of a subject's eyes to obtain electroretinogram, electro-oculogram or visually evoked potential responses. The stimulator comprises a light directing means for directing light from a light source into the subject's eyes, attenuator means for selectably attenuating the light source, photodetector means for producing an output signal representative of the radiant energy directed into the subject's eyes and signal processing means for receiving and processing the output signal to derive therefrom further output signals representative of the radiometric or photometric characteristics of said radiant energy. A light shutter comprising first and second shutter leaves affixed to the shafts of first and second galvanometers is also provided. The shutter leaves are positioned for pivotal movement with the galvanometer shafts to attenuate light passing between the shutter leaves.