You really don't know that? That's an IR device for nightfighing. Pretty advanced stuff and not very much data on it left (obviously). Those were meant to fight in combination with IR-equipped Panthers supported by an "Uhu" (60cm IR searchlight mounted on a SdKfz251/20) becasue the effective range of these devices apparently was limited to 600m max.
From the documents left it seems these IR-equiped untis were pretty effective - there are reports form Panthers taking out enemy tanks at ranges of 2500m. Not very many of these got delivered to frontline units so their impact was not only minor, but rather neglegible.
EDIT: The PDFs Mehlsack pointed at do compiliment my short answer nicely with more technical data.