EINSPANNVORRICHTUNG, INSBESONDERE FUER EINE LICHTLEITER-VORFORM

摘要

A lightguide preform chuck (15) comprises a collet (32) having a slotted conical end (36) and collet restraining means (40/42/45) in engagement with the collet ends but spaced from a collet mid-portion. The restraining means has a coefficient of thermal expansion less than that of the collet whereby under elevated temperature conditions the collet arches into gripping engagement with a lightguide preform held therein.