The invention relates to an optical element for guiding and forming a laser beam, and to a method for recording beam parameters, particularly in a laser system, comprising a carrier substrate (40) and a coating (39), which is applied to at least one side of the carrier substrate (40), and comprising at least one temperature sensor (38). The temperature sensor (38) is comprised of a number of pixels arranged in a matrix, and each respective pixel has at least one temperature-sensitive element (39). The at least one temperature-sensitive element (39) of the pixel is constructed inside the carrier substrate (40) made of silicon.