Method for generating an image in electronic form, image element for an image sensor for image generation and image sensor

摘要

A method for continuously generating a (grayscale) map of a scene in electronic form, characterized by high time resolution and minimal data volume, is presented. The method involves repeated measurement of the instantaneous exposure of the image elements in an image sensor, the start of every exposure measurement being determined autonomously and asynchronously by every image element independently, and hence the redundancy which is typical of synchronous image sensors in the image data to be transmitted being largely suppressed. The stimulation for the purpose of exposure measurement is provided by the autonomous detection of a relative light intensity change in the scene detail which the image element views, by the transient detector in the respective image element. To increase the signal-to-noise ratio and the dynamic range, the exposure measurement is preferably performed on the basis of time, that is to say the exposure of an image element is represented by the period between two asynchronous events. The address of the image element, corresponding to the coordinates of the image element in the sensor array, is transmitted asynchronously at the time of every detection of a light intensity change for the purpose of storage and/or further processing. In addition, the result of the resultant exposure measurement is likewise transmitted together with the address of the image element, asynchronously for the purpose of storage and/or further processing. No external control signals are required for controlling timing, particularly for the exposure measurement. The image sensor is typically implemented in CMOS technology.