The invention provides a method of producing reflectors from glass or glass ceramics comprising the steps of: molding a reflector being open to the outside and having a closed bottom in a mold at a temperature above the transformation temperature; placing the reflector in a recess of a holder; heating up the reflector in the area of its bottom; lifting the bottom of the reflector from below using a die; punching out at least one opening from the bottom by moving at least one plunger into at least one matching opening in the die.